TI: Cyclophosphazenes as polymer modifiers

The utilization of cyclophosphazenes as polymer modifiers is reviewed, with particular concern to their exploitation as versatile chain extenders, possibly for recycle problems, crosslinkers, to enhance mechanical properties of polymeric materials, branchers, to selectively introduce ramifications in linear polymers, and compatibilizers, to favor the formation of blends between originally incompatible organic macromolecules. The great versatility of the synthetic methods put forward for these substrates, together with the ease of controlling their modification, functionalization and reactivity are important parameters for the evaluation of which type of use is more feasible for these trimer…

Comparative Investigation on the Soil Burial Degradation Behaviour of Polymer Films for Agriculture before and after Photo-Oxidation

Polymer films based on biodegradable polymers, polyethylene (PE) and modified PE with oxo-degradable additive were prepared by film blowing. Carbon black (1%) was added to all the films. Commercial biodegradable Ecovio&reg

Caratterizzazione e lavorabilità di nanocompositi a matrice poliestere

R. Marino, N. Tzankova Dintcheva, F.P. La Mantia LLDPE/caly/compatibilizers nanocomposites: rheological behaviour under shear and non-isothermal elongational flow

This lecture summarizes some recent results and ideas about interrelations between degradation and mechanical behaviour of polyolefins. Aspects of the heterogeneous nature of oxidative degradation in the solid state, the feedback mechanism in degradation, effects of morphology, particularly orientation, on the degradation process, and the influence of degradation on plasticity and on the ultimate mechanical behaviour are discussed.

Natural compounds as light stabilizer for a starch-based biodegradable polymer

Abstract The photooxidation behavior of a commercial starch-based biodegradable polymer, i.e., new generation Mater-Bi, loaded with natural stabilizers was investigated in consideration for outdoor agricultural applications. The photooxidation behavior of the biodegradable films was monitored mainly by mechanical tests and spectroscopic analysis. In order to formulate biodegradable films without any synthetic compounds, suitable for outdoor applications and with good photooxidation stability, antioxidants such as α-tocopherol and quercetin (Q) were considered. The results obtained using natural compounds were compared with those obtained by using a synthetic antioxidant and a light stabiliz…

Groups, Theory of

Selective localization of organoclay and effects on the morphology and mechanical properties of LDPE/PA11 blends with distributed and co-continuous morphology

Morphology modification of polymer-filled nanocomposites subjected to non-isothermal elongational flow

Influenza delle lavorazioni sulle proprietà di compositi a base di polimeri biodegradabili e farina di legno

Film blowing of modified polyethylene

Ecocompositi polimerici: polietilene riciclato e cariche organiche naturali

Preparation and Recycling of Plasticized PLA

Stabilizzazione

Film Nanocompositi Polimerici

Role of oxyegen on rheological response of polyethylene–clay nanocomposites to annealing

Effect of Graphene Nanoplatelets on the Physical and Antimicrobial Properties of Biopolymer-Based Nanocomposites

In this work, biopolymer-based nanocomposites with antimicrobial properties were prepared via melt-compounding. In particular, graphene nanoplatelets (GnPs) as fillers and an antibiotic, i.e., ciprofloxacin (CFX), as biocide were incorporated in a commercial biodegradable polymer blend of poly(lactic acid) (PLA) and a copolyester (BioFlex®). The prepared materials were characterized by scanning electron microscopy (SEM), and rheological and mechanical measurements. Moreover, the effect of GnPs on the antimicrobial properties and release kinetics of CFX was evaluated. The results indicated that the incorporation of GnPs increased the stiffness of the biopolymeric matrix and allowed for the t…

Clay-based polymer nanocomposites: photoxidation and stabilisation

ECOCOMPOSITI MATER-BI®/FARINA DI LEGNO: OTTIMIZZAZIONE DELLE PROPRIETA’ ATTRAVERSO ANALISI STATISTICA E BIODEGRADAZIONE

Impiego di poliidrossialcanoati in miscele polimeriche: properietà ed applicazioni

Influence of Different Environments and Temperatures on the Photo-Oxidation Behaviour of the Polypropylene.

The photo-oxidation of polypropylene at two different temperatures and in three different environments—air, distilled water and sea water—has been followed as a function of the irradiation time. The photo-oxidation kinetic is dramatically dependent on the amount of oxygen available for the oxidation reactions and on the temperature. While the photo-oxidation is very fast in air, the degradation is much slower in the two aqueous media. The degradation in sea water is slightly slower than in distilled water. In all cases, the degradation kinetic increases remarkably with the temperature. This behavior has been attributed to the lower oxygen availability for the oxidation reactions of the poly…

MECHANICAL PROPERTIES AND BIODEGRADABILITY OF MATER-BI®/WOOD FLOUR ECOCOMPOSITES

Polyethylene–clay nanocomposite: Effect of annealing under different atmospheres

Effect of the extensional flow on the properties of oriented nanocomposite films for twist wrapping

In this study, we examined the mechanical behavior of nanocomposite films based on polyethylene (PE) and pristine PE films. The films were prepared by film blowing and were then cold-drawn at low temperature. The experimental results show that cold drawing significantly enhanced the orientation; with increasing draw ratio (DR), the elastic modulus and tensile strength of the PE films strongly increased, particularly in the presence of the organoclay. To obtain polymeric films suitable for twist wrapping, the films must be sufficiently stiff so that no shrinkage or elastic recovery occur during or after twisting. The elongation at break and the yield strain sharply decreased with orientation…

Correlation between processability and properties of a high density polyethylene by a rheological approach

The thermal-oxidative and thermal-mechanical stability of high density polyethylene (chromium based catalyst technology) was examined at many different temperatures using a rheological approach. The changes in molecular structure, which take place during processing, have been studied using a Clextral co-rotating twin-screw extruder in comparison with dynamic measurements performed with a rotational rheometer under definite conditions of temperature, strain and frequency and in presence of air. In order to evaluate the degradation response, an investigation of elastic modulus G' as a function of frequency ω on the residual sample after ageing has been carried out. The molecular weight increa…

Use of PP-g-OXA in the Compatibilization of PP/LCP Blends

Abstract Adding small amounts of liquid crystalline polymers (LCP) to flexible thermoplastic matrices (FTP) allows to enhance the mechanical and thermomechanical properties. Therefore it is possible to obtain materials with new properties only by simple mixing. A strong shortcoming is the incompatibility between LCP and FTP that leads to materials with very poor properties unusable for commercial pourposes. The presence of a compatibilizer is therefore required. Oxazoline functionality is known to be highly reactive toward many other functional groups and then oxazoline functionalized polymers can be efficiently used as compatibilizer precursors. In this work the compatibilizazion of polypr…

Fibre antimicrobiche per applicazioni chirurgiche

Morphology modification of a polyethylene/clay nanocomposite samples under convergent flow

The morphology of PE/CL nanocomposite samples subjected to convergent flows is studied. Elongational flow – the typical flow involved in spinning and film-blowing processing operations – significantly increases with the reduction of the capillary diameter. The values of the convergent extensional stress (calculated by Cogswell's formula) for the PE/CL systems, for all the adopted capillary geometries, are greater than the calculated values for pure polyethylene. The applied convergent flow, at the entrance of the capillary, is able to change the clay morphology and consequently the final material properties on the PE/CL system with limited affinity between the matrix and organo-modified cla…

Structure-properties relationships of polyhedral oligomeric silsesquioxane (POSS) filled PS nanocomposites

The polyhedral oligomeric silsesquioxane (POSS) additivated polystyrene (PS) based nanocomposites were pre- pared by melt processing and the structure-properties relationships of the POSS-PS systems were compared to those of the neat PS. In order to investigate the effect of these structural parameters on the final properties of the polymer nanocompos- ites, five different kinds of POSS samples were used, in particular, POSS with different inorganic cage and with different organic pendent groups. The rheological investigation suggests clearly that the POSS acts as a plasticizer and that the processability of the PS was positively modified. The affinity between the POSS samples and the PS ma…

Improvement of the photo-stability of nanocomposite based LDPE/EVA films

Rheological behaviour of PAN-based electrolytic gel containing tetrahexilammonium and magnesium iodide for photoeletrochemical applications

LLDPE/caly/compatibilizers nanocomposites: rheological behaviour under shear and non-isothermal elongational flow

Properties-morphology-processing relationships in polymer-based clay nanocomposites

Caratterizzazione di nanocompositi a base di polimero biodegradabile

Polyolefin/clay nanocomposite drawn fibres with and without compatibilizer: structural analyses and mechanical performance

Effetto del flusso elongazionale su sistemi nanocompositi a matrice polimerica e silicati: morfologia e proprietà meccaniche

Photo-oxidation and improving of the photo-resistance of LLDPE based nanocomposites

Torque-rheometry investigation of model transreactions involving condensation polymers

Influence of a sterically hindered amine on the photo-oxidation of low density/linear low density polyethylene blends

Abstract Low density/linear low density polyethylene blends show a rate of degradation of the mechanical properties during photo-oxidation which increases with the content of the linear polymer. The use of a sterically hindered amine as UV stabilizer greatly improves the resistance of these blends to UV irradiation. The effectiveness of the stabilizer increases with the content of linear low density polyethylene.

Photo-stability of LDPE/EVA – based nanocomposite films

PROCESSING AND CHARACTERIZATION OF THE POLYMER/CNTs NANCOMPOSITE FIBRES.

Oxazoline-containing compatibilizers for polyamide/SAN and polyamide/ABS blends

Polyamide (PA) and acrylonitrile/butadiene/styrene copolymer (ABS) may appear as a mixture in the recycled plastic stream. The incompatibility of these blends results in a blend with poor mechanical properties. The aim of this work is to partially convert the nitrile groups of the acrylonitrile/styrene copolymer (SAN) into oxazoline groups by reaction with aminoethanol (AE). Such modified SAN (SAN-m) can react with the amine or carboxylic acid end groups of PA, and therefore used as compatibilizers for blends of PA with ABS. SAN-m was found to reduce the SAN-domain size in the PA/SAN-blends. The initial acrylonitrile content of SAN-m had a strong influence on the degree of conversion into o…

Preparazione e caratterizzazione di polimeri biodegradabili caricati con riempitivi naturali

Nanocompositi da Polietileni e Copolimeri PE-g-MA con Diversa Struttura Molecolare

Effect of fillers on the properties of recycled polymers

The main problems in post-consumer plastics recycling are due to the degradation undergone during lifetime and during processing steps. Moreover, for heterogeneous recycling, the incompatibility among the different polymeric phases give rise to secondary materials with low mechanical and thermomechanical properties. The properties-reprocessing relationships are an important tool for determining not only the properties of the recycled polymers but also the strategies to apply (processing conditions, stabilisers, fillers, compatibilizers, etc) in order to obtain recycled polymers with good mechanical properties. In this work the effect of adding inert fillers and modifier agents to recycled p…

Predicting the photoageing and photostabilization of polymer nanocomposites

Composites from biodegradable polymers and wood flour

Morfologia e proprietà di nanocompositi a base di poliammide e CNTs: effetto della geometria e della funzionalizzazione superficiale

LAVORABILITA E PROPRIETA MECCANICHE DI POLIMERI BIODEGRADABILI

Photooxidative behaviour of polyethylene/polyamide-6 blends

International audience; The photochemical behaviour of several polyethylene/polyamide-6 blends was studied under conditions of artificial accelerated weathering. Particular attention was paid to five different compositions ranging from pure polyethylene to pure polyamide with blends of PE/PA-6 of various compositions: 75/25, 50/50 and 25/75 wt/wt%. Analysis by infrared spectroscopy of the chemical modifications caused by photooxidation showed that exposing the polyethylene/polyamide-6 blends to UV-light irradiation led to the formation of oxidation photoproducts in both polymer phases. In agreement with both the mechanical and spectroscopic analyses, the photooxidation rate of the blends wa…

Morphology and Properties of Polyethylene/Clay Nanocomposite Drawn Fibers

The influence of an elongational flow on the morphology of PE/clay nanocomposite drawn fibers was studied. An increase of the elastic modulus and the tensile strength as well as a decrease of the elongation at break are observed with increasing draw ratio. The applied elongational gradient orients the polymer chains and the clay particles along the spinning direction. When the applied flow results in the formation and the orientation of exfoliated nanoparticles, a pronounced increase of the mechanical properties is observed. The dispersed clay particles can be broken and oriented by the extensional flow, which might indicate a flow induced intercalated/exfoliated morphology transition.

Reactive Compatibilization of PBT/EVA Blends with an Ethylene‐Acrylic Acid Copolymer and a Low Molar Mass Bis‐Oxazoline

GREEN COMPOSITES BASED ON BIODEGRADABLE POLYMERS AND WOOD FLOUR

Effetto della Polarità dei Componenti sulle Proprietà di Nanocompositi

Green composites of organic materials and recycled post-consumer polyethylene

Morphology modification in nanofilled polymer based systems upon shear and elongational flow

Compositi Verdi con Polietilene Riciclato e Cariche Organiche

Use of Biochar as Filler for Biocomposite Blown Films: Structure-Processing-Properties Relationships

In this work, biocomposite blown films based on poly(butylene adipate-co-terephthalate) (PBAT) as biopolymeric matrix and biochar (BC) as filler were successfully fabricated. The materials were subjected to a film-blowing process after being compounded in a twin-screw extruder. The preliminary investigations conducted on melt-mixed PBAT/BC composites allowed PBAT/BC 5% and PBAT/BC 10% to be identified as the most appropriate formulations to be processed via film blowing. The blown films exhibited mechanical performances adequate for possible application as film for packaging, agricultural, and compost bags. The addition of BC led to an improvement of the elastic modulus, still maintaining h…

Reactive compatibilization of PA6/LDPE blends with an ethylene–acrylic acid copolymer and a low molar mass bis-oxazoline

Abstract A sample of polyamide-6 (PA) was blended with low density polyethylene (LDPE) in the 80/20 wt/wt ratio, either without and with 2 phr of an ethylene–acrylic acid copolymer (EAA), Which was known to behave as a compatibilizer precursor, and the effect of the addition of small amounts (0.2 or 0.35 phr) of a fourth component, 2,2′-(1,3-phenylene)-bis(2-oxazoline) (PBO), was investigated. The reactions of PBO with EAA, PA and their blends were studied by recording as a function of time the torque applied to the blending apparatuses and by studying the solubility behavior of the products in formic acid. The PALDPE blends were prepared in a co-rotating twin screw extruder and were charac…

Morfologia e proprietà di sistemi nanocompositi poliammide/CNTs e poliammide/carbon black sottoposti a stiro elongazionale

Nanocompositi a base di polistirene e ossido di zinco: azione disperdente delle molecole POSS

Photo-oxidation behaviour of polyethylene/multi-walled carbon nanotube composite films

USE OF BIODEGRADABLE POLYMERS FOR FOAM EXTRUSION

Biodegradation paths of Mater-Bi®/kenaf biodegradable composites

Composites obtained from biodegradable polymers and natural–organic fillers are attracting increasing interest, thanks to the environmental advantages they promise. On the other hand, the real biodegradation performance of a biodegradable polymer/natural organic filler composite should be assessed by performing specific biodegradation tests. These are often carried out under laboratory conditions, but more realistic conditions should be taken into account. In this work, a systematic study on the biodegradation of kenaf fiber-filled Mater-Bi® composites in different environments is presented, and some interesting parameters for the understanding of the optimum way to obtain a fast degradatio…

Morphology, Rheological and Mechanical Properties of Isotropic and Anisotropic PP/rPET/GnP Nanocomposite Samples

The effect of graphene nanoplatelets (GnPs) on the morphology, rheological, and mechanical properties of isotropic and anisotropic polypropylene (PP)/recycled polyethylene terephthalate (rPET)-based nanocomposite are reported. All the samples were prepared by melt mixing. PP/rPET and PP/rPET/GnP isotropic sheets were prepared by compression molding, whereas the anisotropic fibers were spun using a drawing module of a capillary viscometer. The results obtained showed that the viscosity of the blend is reduced by the presence of GnP due to the lubricating effect of the graphene platelets. However, the Cox–Merz rule is not respected. Compared to the PP/rPET blend, the GnP led to a slight incre…

The role of filler type on the photo-oxidation behaviour of micro- and nano-filled polypropylene

Taking advantage of the functional synergism between carbon nanotubes and graphene nanoplatelets to obtain polypropylene-based nanocomposites with enhanced oxidative resistance

Carbon Nanotubes (CNT) and Graphene Nanoplatelets (GNP) were incorporated in Polypropylene (PP) as single filler (CNT=1, 2 and 4 %wt. and GNP=2, 4, and 6 %wt.) and in hybrid form (CNT:GNP weight ratio 2:2, 2:4 and 4:2) using a prototype miniature Twin Screw Extruder (TSE) coupled with a double slit rheological die, in order to assess in-line the extent of nanofiller dispersion and to deliver PP-based nanocomposites with enhanced thermo-oxidative stability. The morphological, electrical and mechanical properties, as well as the resistance to thermal and photo degradation of the composites containing single nanofillers (PP/CNT and PP/GNP) were compared with those of hybrid PP based nanocompos…

Torque rheometry investigation of model transreactions involving condensation polymers: I. Polyesters

The chemical transformations taking place when poly(ethylene terephthalate) (PET) or poly(ethylene naphthalate) (PEN) are blended in the melt with different low molar mass substances containing hydroxyl, carboxyl, or amine functional groups have been investigated as models of the transreactions, undergone by the polyesters in reactive blending operations. The polyester molecular weight changes caused by the alcoholysis, acidolysis, aminolysis, and esterolysis reactions have been monitored by torque-rheometry, using a Brabender Plasticorder static mixer. The degradation of the polyesters by hydrolysis was also studied, under similar conditions, by the addition of a water-releasing substance …

Thermomechanical degradation of polyethylene/polyamide 6 blend-clay nanocomposites

Film Blowing of Biodegradable Polymer Nanocomposites for Agricultural Applications

Films for agricultural applications, such as greenhouses films or mulching films are generally made of polyolefins such as linear low-density polyethylene (LLDPE) or low-density polyethylene. However, the use of biodegradable and/or compostable polymers is increasing, which enjoy the additional advantage that they can be left on the site since a fine life would be gradually assimilated to the underlying soil. Nevertheless, biodegradable polymeric films often do not have suitable mechanical performances. In this work, biodegradable polymer-based nanocomposite films are prepared by film blowing and compared with traditional LLDPE based nanocomposites. In particular, a biodegradable polymer bl…

Annealing time dependent rheological properties of polyethylene based nanocomposites

Reduction and reuse of waste: design and new generation plastics

Relazioni proprietà-morfologia-lavorazione in materiali nanocompositi a matrice polimerica

Preliminary Evaluation of Plasmix Compound from Plastics Packaging Waste for Reuse in Bituminous Pavements

Finding an appropriate technical solution for reusing waste plastics is crucial for creating a circular plastic economy. Although mechanical recycling is the best option for recycling post-consumer plastics, some heterogeneous mixed plastics cannot be recycled to produce secondary material due to their very low properties. In this case, alternative routes should be considered in order to limit their disposal as much as possible. Therefore, in order to solve the environmental problems in the landfills of plastic waste recycling, and to improve the mechanical performance of bitumen for road pavement, the reuse of these post-consumer plastic wastes are preliminarily evaluated for the modificat…

Optimisation of the processing conditions in the recycling of polycondensation polymers

Degradazione Di Argille Modificate Organicamente

Effect of elongational flow on morphology and properties of Polymer/CNTs nanocomposite fibres

Influence of the matrix on photo-oxidative degradation of polyolefin based nanocomposite films

Recycling and Thermomechanical Degradation of LDPE/Modified Clay Nanocomposites

The special features of polymer nanocomposites are continually gaining interest both in academia and in industry. The latter is especially experiencing an increase in interest towards this class of polymer composites, and this is leading to the first concerns about their reprocessing and reciclability. Here, a systematic study on the behavior of LDPE/Cloisite 15A systems upon reprocessing in a single-screw extruder is described, focusing on rheological, mechanical, and morphological properties changes. The investigated systems show a very complex thermomechanical degradation behavior, with the degradation of the clay modifier and different degradation paths involving the polymer matrix; all…

Morphology and mechanical properties of nanofilled polymer blends

Effect of elongational flow on the morphology and mechanical properties of LLDPE/clay nanocomposites

Effetto della presenza di piccoli quantitativi di PLA nel riciclo di contenitori in PET

Photo-oxidation behaviour of micro- and nano-filled polypropylene: effect of the filler type and compatibilizer precursor

Photo-oxidation behaviour of composite polyethylene/MW-CNTs

Innovazione tecnologica nel Distretto Produttivo della Pesca di Mazara del Vallo

Ecocompositi polimerici caricati con riempitivi organico-naturali

Effect of the nanotube aspect ratio and surface functionalization on the morphology and properties of multiwalled carbon nanotube polyamide-based fibers

In this study, the effect of the carbon nanotube (CNT) aspect ratio and surface functionalization on the mechanical behavior and morphological changes of polyamide (PA)-based fibers was investigated. Composites were prepared by the melt blending of CNTs with PA, and at a later time, the fibers were prepared by melt spinning and cold drawing. A reinforcement effect was noticed for all of the CNTs samples, and the increase in the mechanical properties and dimensional stability was more pronounced for highly oriented filaments. When the elongational flow was increased, the orientation of CNTs along the fiber direction was observed, but the nanotube alignment was much more difficult for CNTs wi…

The Effects of Nanoclay on the Mechanical Properties, Carvacrol Release and Degradation of a PLA/PBAT Blend

The formulation of polymeric films endowed with the abilities of controlled release of antimicrobials and biodegradability is the latest trend of food packaging. Biodegradable polymer (Bio-Flex&reg

Mechanical properties of recycled polymers

Modifications of structure and morphology of the polymers induced by the thermomechanical stress (or by the presence of water for some polymers) during reprocessing can cause a drastic deterioration of mechanical properties of the recycled material. The property reprocessing relationships are an important tool to determine not only the properties of the recycled polymers but also the strategies to use (processing conditions, stabilizers, fillers, compatibilizers, etc) in order to obtain recycled polymers with good mechanical properties. In this work, typical behaviour of some mechanical properties as a function of the number of reprocessing operations is discussed and correlated with their …

Photo-oxidation resistance of polyethylene/carbon nanotubes composites: aspect ratio and surface functionalization effect

Thermo-mechanical degradation of LDPE based nanocomposites

The role of organoclay in the morphology modification and in the properties in polyethylene/polyamide blend systems

Morphology and properties of polyamide/CNTs nanocomposite fibres

On the use of natural inorganic materials as fillers for recycled post-consumer ploastics

Biodegradable Polymers for the Production of Nets for Agricultural Product Packaging

It is well known that the need for more environmentally friendly materials concerns, among other fields, the food packaging industry. This regards also, for instance, nets used for agricultural product (e.g., citrus fruits, potatoes) packaging. These nets are typically manufactured by film blowing technique, with subsequent slicing of the films and cold drawing of the obtained strips, made from traditional, non-biodegradable polymer systems. In this work, two biodegradable polymer systems were characterized from rheological, processability, and mechanical points of view, in order to evaluate their suitability to replace polyethylene-based polymer systems typically used for agricultural prod…

Bionanocomposite Blown Films: Insights on the Rheological and Mechanical Behavior.

In this work, bionanocomposites based on two different types of biopolymers belonging to the MaterBi® family and containing two kinds of modified nanoclays were compounded in a twin-screw extruder and then subjected to a film blowing process, aiming at obtaining sustainable films potentially suitable for packaging applications. The preliminary characterization of the extruded bionanocomposites allowed establishing some correlations between the obtained morphology and the material rheological and mechanical behavior. More specifically, the morphological analysis showed that, regardless of the type of biopolymeric matrix, a homogeneous nanofiller dispersion was achieved

Accelerated weathering of polypropylene/wood flour composites

The role of aspect ration in the mechanical properties of lignocellulosic ecocomposites obtained from MaterBi(R)

The antioxidant effect in controlling thermal degradation of a LDPE blow film

It is well known that antioxidants are widely used to prevent thermal degradation of high density and linear low density polyethylene. Antioxidants are not always present in low density polyethylene and only small amounts are usually added to these resins. In this work the effect of an antioxidant system on a low density resin having MFI (190 °C/2.16 kg)=2 g/10′ and density 0.9230 g/cm3 has been studied. Its effect on melt viscosity has been studied by means of a batch mixer and the torque vs time behaviour has been analysed. The results show that a maximum in the torque vs time curve can be seen for the material containing antioxidant. In contrast, the material without antioxidant does not…

EVA-montmorillonite nanocomposites: effect of processing condition

The aim of this study is to examine the effect of the compounding apparatus and of processing conditions on the properties of an organoclay-poly[ethylene-co-(vinyl acetate)] (EVA) nanocomposite. The filled materials were prepared using either a discontinuous batch mixer, a single screw extruder, a counter rotating intermeshing twin-screw compounder or a corotating intermeshing twin-screw extruder. The characterization of the obtained nanocomposites was performed by XRD, thermogravimetry, mechanical and rheological measurements. The study has shown the possibility of producing nanocomposites based on EVA and a commercial organoclay (Cloisite 15A) by several mixing equipments. In fact all the…

Photo-oxidation Behaviour of EVA Antimicrobial Films

Relazione proprietà-morfologia-parametri di processo in materiali nanocompositi a matrice polimerica

Performance of MaterBi(R) based ecocomposites

Relazione struttura-proprietà in nanocompositi POSS-PS

Fibre a base di poliammide e nanotubi di carbonio: proprietà e morfologia

Proprietà meccaniche di compositi poliolefinici caricati con riempitivi organico-naturali: utilizzo di prmotori di adesione

Photochemical stabilization of linear low-density polyethylene/clay nanocomposites: Towards durable nanocomposites

International audience; This article reports a study of the chemical modifications of LLDPE/nanoblend nanocomposites exposed to UV light in conditions of artificially accelerated ageing and natural weathering. Analysis by infrared spectroscopy of the chemical modifications produced by photoageing shows that the presence of an organo-clay leads to the decrease of the oxidation induction time of the polymer (LLDPE), which results in lower durability of the nanocomposites. Protection against photooxidation was tested with different kinds of UV stabilizers and with a metal deactivator. It is shown that the metal deactivator is very efficient in stabilizing the nanocomposite since it totally can…

Nanocompositi a base di copolimero stirene-butadiene-stirene e nanotubi di carbonio: morfologia e proprietà

On the Role of Extensional Flow in Morphology and Property Modifications of MWCNT/Polyamide-Based Fibers

Unfilled and MWCNT-filled PA fibers are prepared and the effect of the extensional flow on their mechanical performance and morphological variations is investigated. Morphological analyses using SEM, TEM, and SAXS suggest a stronger orientation of the MWCNTs along the fiber direction with increasing extensional flow. A particular MWCNT bundle formation in the PA drawn nanocomposite fibers is observed for the first time, and a pull-out of the central nanotube in some bundles is noted. The maintenance of the "shish-kebab" structure upon extensional flow is responsible for the mechanical improvements and dimensional stability in MWCNT-filled PA fibers.

Influence of the morphology on the photo-oxidation behaviour of polymer based nanocomposites

CARATTERIZZAZIONE E LAVORABILITA DI NANOCOMPOSITI A MATRICE POLIESTERE

The silent work of speech. On an Enactive Grammar’s Insight

Many research programs have been worked out in recent years in order to account for an apparently trivial aspect of the human language activity. We refer to the fact that every speaker hears the sound of his own words. Our paper aims to embed this empirical insight in the theoretical framework of the so-called enactive grammar. This choice is justified by the fact that the enactive grammar introduced a formal distinction which allows to provide a clear formulation of the jakobsonian assert. In order to highlight this point, the paper will be subdivided into seven sections. The first section will be devoted to the experience of the hearing oneself speak. The second one will examine this expe…

Formulation of agricultural films by using of the recycled polymers: resistance to the photo-oxidation

Photo-oxidation behaviour of composite polyethylene/MW-CNTs films

Modification of viscoelastic properties of polyethylene based nanocomposites after thermal treatment

Polymer-based 'green' composites

Thermal treatment dependent rheological properties of polyethylene based nanocomposites

Preparation and Recycling of Plasticized PLA

Poly(lacticacid)(PLA)hasbeengainingarisinginterestoverthe last years as a biodegradable and environmental-friendly substitute of traditional non-biodegradable poly-mers.Several ways exist to synthesize PLA, however, poly-merization through lactide formation is the most used onindustrial scale, allowing to obtain optimum results interms of mechanical and thermal properties.

Effect of cold drawing on mechanical properties of biodegradable fibers.

Purpose Biodegradable polymers are currently gaining importance in several fields, because they allow mitigation of the impact on the environment related to disposal of traditional, nonbiodegradable polymers, as well as reducing the utilization of oil-based sources (when they also come from renewable resources). Fibers made of biodegradable polymers are of particular interest, though, it is not easy to obtain polymer fibers with suitable mechanical properties and to tailor these to the specific application. The main ways to tailor the mechanical properties of a given biodegradable polymer fiber are based on crystallinity and orientation control. However, crystallinity can only marginally be…

Injection moulding of recycled polyethylene-natural organuc fillers composites

Morphology and properties of CNTs and carbon black filled polyamide fibres

Morfologia e proprietà di fibre polimero/CNTs

Shear flow characterization of blends containing liquid crystal polymers

A simple phenomenological approach is proposed in order to predict the presence of minima in the viscosity-composition curves of blends of thermoplastic with liquid crystal polymer (LCP). When the viscosity of the liquid crystal polymer is larger than that of the thermoplastic matrix, a minimum is observed. A possible explanation of the presence of yield stress in the flow curves of these blends is also given.

The Effect of Calcium Carbonate on the Photo-Oxidative Behavior of Poly(butylene adipate-co-terephthalate)

The aim of this work is to evaluate the influence of nanosized CaCO3 on the photo-oxidation of poly(butylene adipate-co-terephthalate) (PBAT)-based nanocomposites. The PBAT/CaCO3 nanocomposites are prepared by using a corotating twin-screw extruder with 0, 2, and 5 wt% of CaCO3. The films are obtained by film blowing process. Specimens of the nanocomposites and that of the pure polymer are subjected to accelerated aging with a cycle of 8 h of light at a temperature of 55 °C followed by 4 h condensation at 45 °C to evaluate the effects of the CaCO3 addition on the photo-oxidation of PBAT. The results indicate that the modulus and tensile strength of the nanocomposites are increased significa…

Orientation induced brittle – Ductile transition in a polyethylene/polyamide 6 blend

Abstract Polyamide/polyolefin blends are of scientific and technological interest but, on the other hand, the different chemical nature of the two components makes them incompatible, resulting in unsatisfactory physical properties and making compatibilization necessary. In particular, although the two components are ductile, the binary blends can show brittle behaviour. It is also known that the effect of the elongational flow (and then of the induced orientation) on polymer blends is a decrease of elongation at break with increase of the degree of orientation. In this work, the effect of orientation on the mechanical properties of a low density polyethylene/polyamide 6 incompatible blend w…

Rheological Behaviour of polyolefin based nanocomposites in isothermal and non-isothermal elongational flow

Influence of Nisin on Photo-stability of EVA Antimicrobial Films

An investigation of the compatibilization of blends of polyethylene and a semirigid liquid crystalline polymer

The mechanical properties of blends with liquid crystalline polymers are in general poor and lower than those expected on the basis of additivity rule because of the strong incompatibility between the flexible and rigid components. Compatibilization is then necessary to enhance the adhesion between the two phases and then to improve the final properties of these blends. The addition of maleic anhydride functionalized polymers could give rise to some compatibilization because of possible reactions between the maleic anhydride group and the end groups of the liquid crystalline polymers. These reactions do not seem to occur in blends of polyethylene and a semirigid liquid crystalline polymer. …

On The Use Of Polyolefins Based Nanocomposites For Film Blowing Applications

Polymer electrolytes based on PAN and mixed salts for photoelectrochemical appilcations: formulation and characterization

On the role of extensional flow in morphology and properties modifications in MW-CNTs and carbon black polyamide-based fibres

Apparecchiatura per la misura della deformazione sotto carico

EFFETTO DI NANO-ARGILLE ORGANO-MODIFICATE E COMPATIBILIZZANTI SULLE PROPRIETA’ DI NANOCOMPOSITI A BASE DI LLDPE

Synthesis, properties and processability of a new class of semirigid liquid crystalline copolyesteramides

Abstract A new family of semirigid main chain liquid crystalline polymers (LCPs), referred to as SBAN, characterized by fairly good processability and mechanical properties, and improved thermal resistance, have been synthesized by the melt polycondensation of sebacic acid (S), 4,4′-dihyhxybiphenyl (B), 4-aminobenzoic acid (A), and 2-hydroxy-6-naphthoic acid (N), in a wide range of compositions. The molar concentration of the A ahd N units, in these LCPs must be kept lower than ca 40 and 60%, respectively, in order to avoid the formation of homopolymeric blocks, which impair spinnability. The presence of A units grants the formation of hydrogen bonds between neighboring macromolecules, and …

Polyolefin based nanocomposites: a method to achieve better dispersion of nanoclays in PE films and improve their physical properties

Thermo-Mechanical Degradation of LDPE-Based Nanocomposites

Thermo-mechanical degradation of LDPE-based nanocomposites was studied by mainly investigating the rheological properties. For all of the investigated processing conditions, the viscosity of the nanocomposites was higher than that of the pure-LDPE matrix, but on increasing the severity of the mixing conditions, the difference between the viscosity of the nano-filled polymer and that of the pure LDPE decreased. The X-ray traces of the nanocomposites suggest that intercalation has been achieved during the melt, when less-severe processing conditions were used. At severe processing conditions (longer mixing time, high temperature and shear stress) the thermo-mechanical degradation was accelera…

Effect of stress and temperature on the thermomechanical degradation of a PE-LD/OMMT nanocomposites

Thermomechanical degradation of nanocomposites is a topical issue that has not been fully investigated as demonstrated by the low number of papers available in the literature regarding this spe- cific aspect. In particular, with regards to low density polyethylene/clay nanocomposites, the degrada- tion behavior is very complex since it involves the degradation paths of both the polymer matrix and the organomodified nanoclay. In the present work, the effects of mechanical stress and temperature on the thermomechanical behavior of PE-LD/organomodified clay nanocomposites and the degradation paths were investigated by rheological, FT-IR and mechanical methods. The results have shown that the t…

Effect of the compatibilization on the photooxidation of a PA6/LDPE blend and their clay nanocomposites

Influence of calcium‐based fillers and vegetable oil on the processability and yield behavior of polyolefins

The mixing of different polyolefins, several calcium-based fillers, and a type of vegetable oil was investigated. The effect of viscosity and type of polyolefin on Young's modulus, yield stress, and elongation at yield has been determined. Tensile and machine torque properties have been studied for both mixing at 180°C and at 250°C as a function of the content of several types of calcium carbonate or calcium hydroxide filler. The influence of the addition of a sunflower oil as a lubricant has also been characterized. SEM micrographs indicate some problems of the formation of agglomerates and the influence of particle size on matrix morphology and filler/matrix adhesion. Physical and chemica…

Rheological behaviour of PAN-based electrolytic gel for photoeletrochemical applications

LDPE/PA6/compatibilizer films: mechanical and rheological behaviour

The role of elongational flow in morphology modification of Polyethylene/OMMT nanocomposite system

Polyethylene/clay nanocomposite: morphology and mechanical properties modification under convergent flow

RECYCLING AND THERMOMECHANICAL DEGRADATION OF POLYETHYLENE/ORGANO-MODIFIED CLAY NANOCOMPOSITES

Mechanism of formation of char coating in LDPE/organoclay nanocomposites

Effect of environmental conditions on the durability of polycarbonate for the protection of cultural heritage sites.

Polycarbonate is a good material for covering and protecting cultural heritage sites because of its durability, mechanical properties, and transparency. However, polycarbonate degrades under environmental weathering with a significant decrease of physical and mechanical properties and loss of transparency. In this work, the contemporary presence of ultraviolet irradiation and different temperature and moisture conditions have been taken into account to study the environmental degradation of this polymer with regard to its mechanical and optical properties. The photo-oxidation reactions cause a decrease in the molecular weight and the formation of many oxygenated species. The hydrolytic sci…

Effect of Moisture Content on the Processing and Mechanical Properties of a Biodegradable Polyester

This work is focused on the influence of moisture content on the processing and mechanical properties of a biodegradable polyester used for applications in injection molding. The pellets of the biodegradable polyester were exposed under different relative humidity conditions at a constant temperature before being compression molded. The compression-molded specimens were again placed under the above conditions before the mechanical testing. With all these samples, it is possible to determine the effect of moisture content on the processing and mechanical properties separately, as well as the combined effect of moisture content on the mechanical properties. The results obtained showed that th…

Effect of adding an organically modified clay to a polyethylene/polyamide blend in the presence of compatibilizing agents

Durabilità dei film polimerici biodegradabili

On the use of PET-LCP copolymers as compatibilizers for PET/LCP blends

Copolyesters of poly[ethylene terephthalate) (PET) with a liquid crystalline polymer (LCP), SBH 1:1:2, have been synthesized by the polycondensation, carried out in the melt at temperatures up to 300 degrees C of sebacic acid (S), 4,4'-dihydroxybiphenyl (B), and 4-hydroxybenzoic acid (H) in the presence of PET. The PET-SBH copolyesters have been characterized by differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, etc., and the relationships between properties and preparation conditions are discussed. The copolyesters show a biphasic nature, which is more evident for the products synthesized with a thermal profile comprising relatively lower temperatures (220-…

Recycling and Thermomechanical Degradation of LDPE/Modified Clay Nanocomposites

Effetto di differenti metodi di preparazione sulle proprietà morfologiche e fisiche di nanocompositi a base di miscele HDPE/PA6

Compositi "verdi" a base di polimeri biodegradabili e riempitivi organico-naturali

Effect of processing temperature and mixing time on the properties of PP/GnP nanocomposites

Abstract During processing of molten polymers the thermal and mechanical stress acting on the melt in presence of oxygen can induce degradation with a modification of the chemical structure of the polymers. This picture can become even more relevant if the melt is a multiphasic polymer system. In this last case, the effects of the degradation depend also on the presence of a second phase and on the interactions between the two phases. In this work, the effect of the processing conditions, temperature and time, have been considered in order to investigate the thermo-mechanical and thermo-oxidative degradation of nanocomposites made by polypropylene and different contents of graphene nanoplat…

Nuova cassetta in Polistirene Espanso (EPS) per il trasporto del pesce

EFFECT OF ORGANOCLAY ON THE MORPHOLOGY AND MECHANICAL PROPERTIES OF POLYETHYLENE/POLYAMIDE BLENDS

POSS-poly(ethylene-co-acrylic acid) nanocomposites: physical interaction

Degradation and stabilization of the polyolefins and of the filled-polyolefins

Influence of photo-oxidation on the performance and soil degradation of oxo- and biodegradable polymer-based items for agricultural applications

Abstract The examination of the aging behavior of polymers, blends, composites, items, etc. under different environmental conditions is a priority issue for assessing the possible applications and establishing the lifetime. In agriculture, plastic items (mulch films, irrigation tubes, etc.) are widely used and subjected to solar UV exposure that can induce photo-oxidation on macromolecular chains. Therefore, weathering under outdoor conditions and accelerated degradation tests are performed for simulating aging processes during the lifetime of materials and select appropriate stabilizers to be used. In the last decades, oxo- and biodegradable polymers have been investigated and used in agri…

Film di EVA con attività antibatterica

Natural compounds as light stabilizers for biodegradable polymers

The role of different dispersing additives in the photo-oxidation behaviour of polyolefin-based OMMT nanocomposites

PBAT Based Composites Reinforced with Microcrystalline Cellulose Obtained from Softwood Almond Shells

This study explores the processability, mechanical, and thermal properties of biocompostable composites based on poly (butylene adipate-co-terephthalate) (PBAT) as polymer matrix and microcrystalline cellulose (MCC) derived from softwood almond (Prunus dulcis) shells (as-MCC) as filler at two different weight concentration, i.e., 10 wt% and 20 wt%. The materials were processed by melt mixing and a commercial MCC (c-MCC) was used as filler comparison. The fibrillar shape of as-MCC particles was found to change the rheological behavior of PBAT, particularly at the highest concentration. The melt mixing processing allowed obtaining a uniform dispersion of both kinds of fillers, slightly reduci…

Effect of a Compatibilizer on the Morphology and Properties of Polypropylene/Polyethylentherephthalate Spun Fibers

Fibers spun by melt spinning of binary and ternary polypropylene/ polyethylenetherephthalate blends have been produced and characterized in order to investigate the effect of a compatibilizer on their morphology and mechanical properties. The compatibilizer was a maleic anhydride-functionalized rubber copolymer. The effect of the compatibilizer was well evident in the isotropic state, as the morphology became very fine, the size of the dispersed particles was very small, and the adhesion was better. The effect of the compatibilizer on the mechanical properties is very relevant, especially in the elongation at break. On the contrary, no relevant effect was observed in the anisotropic oriente…

Preparazione e caratterizzazione di film poliolefinici nanocompositi per applicazioni in agricoltura

Preparation and characterization of polyolefin- based nanocomposite blown films for agricultural applications

Polyolefin-based films were prepared in the presence of two different organo-modified clays and characterized. The influence of organo-modifier and matrix composition on film morphology and properties were investigated using SEM, XRD, UV-Vis, FT-IR, contact-angle measurements and mechanical tests. The filler increased the films' rigidity and tear strength. Transparencies were almost unchanged in the visible range, but were reduced for harmful radiation. The presence of the clay increases the greenhouse effect, i.e. it hinders the passage of thermal emission from the soil to the outer part of the greenhouse during the night. The wettability of the materials was not influenced by the presence…

Degradazione di nanocompositi polimerici

Rheological and Mechanical Behavior of LDPE/Calcium Carbonate Nanocomposites and Microcomposites

The increase of the interest in polymer nanocomposites has been leading to continuous growing search toward nanofillers alternative to the widely known clay-based ones. One of these possible alternatives is represented by calcium carbonate nanoparticles, which have not been widely investigated in such context. In this article, a study on the rheological and morphological behavior of dif- ferent low density polyethylene-calcium carbonate nanocomposites, compared with a reference calcium carbonate microcomposite, is presented. Several different nanosized calcium carbonates at different amounts were used. The results from the rheological and me- chanical tests outlined that only minor changes …

An Additive Model to Predict the Rheological and Mechanical Properties of Polypropylene Blends Made by Virgin and Reprocessed Components

In this work, an additive model for the prediction of the rheological and mechanical properties of monopolymer blends made by virgin and reprocessed components is proposed. A polypropylene sample has been reprocessed more times in an extruder and monopolymer blends have been prepared by simulating an industrial process. The scraps are exposed to regrinding and are melt reprocessed before mixing with the virgin polymer. The reprocessed polymer is, then, subjected to some thermomechanical degradation. Rheological and mechanical experimental data have been compared with the theoretical predictions. The results obtained showed that the values of this simple additive model are a very good fit fo…

Processability and biodegradation of wood/biopolymer composites

Photochemical stabilization of LLDPE/clay nanocomposites: towards durable nanocomposites

This article reports a study of the chemical modifications of LLDPE/nanoblend nanocomposites exposed to UV light in conditions of artificially accelerated ageing and natural weathering. Analysis by infrared spectroscopy of the chemical modifications produced by photoageing shows that the presence of an organo-clay leads to the decrease of the oxidation induction time of the polymer (LLDPE), which results in lower durability of the nanocomposites. Protection against photooxidation was tested with different kinds of UV stabilizers and with a metal deactivator. It is shown that the metal deactivator is very efficient in stabilizing the nanocomposite since it totally cancels the prodegradant ef…

Lavorazione e caratterizzazioni di film twist nanocompositi

Caratterizzazione reologica di sistemi biodegradabili nanocompositi

On the Preparation and the Characterization of Polyethylene/Polyamide Blends by Melt Processing in the Presence of an Ethylene(co)acrylic Acid Copolymer and of New Phosphazene Compounds

Samples of HDPE and PA6 have been meltprocessed in the presence of two new phosphazene compounds, CP-2EPOX and CP-2OXA together with an ethylene/ acrylic acid copolymer. The blends have been prepared in an industrial twin-screw extruder by using PA6 and PE in weight ratios of 25/75 and 75/25. When used, 5 phr of EAA and 0.2 phr of CP have been added. The materials have been completely characterized from a rheological, morphological, and mechanical point of view. The results indicate that the additives used caused an increase in the rupture tensile properties, of the impact strength and viscosity especially in the PE-rich blend in the presence of CP-2EPOX. This result can be attributed both …

Effect of the adding of a functionalized nanoclay in polyethylene/polyamide blends

Photooxidation and durability of PE based nanocopomsites

Influence of short-term aging on mechanical properties and morphology of polymer-modified bitumen with recycled plastics from waste materials

Polymer-modified bitumen (PMB) is bitumen that has been specifically engineered with polymer for providing enhanced performance in service. The aging of bitumen is a main aspect that is able to affect its final performance: during the production phase in a hot mix plant, all the binders experience short-term aging due to the high processing temperature. The same is true during the production of the modified binder, when the polymer is dispersed at high temperature in the bitumen mass. This paper aims at studying the effect of short-term aging when using different types of modifiers such as recycled polymers obtained from waste materials. A 50/70 penetration-grade bitumen has been modified, …

Materiali Compositi a Base di Polipropilene e Cariche Organiche Naturali: Proprietà e Applicazioni

The role of the matrix-filler affinity on morphology and properties of polyethylene/clay and polyethylene/ compatibilizer/clay nanocomposites drawn fibers

In this work the structural variations and mechanical performance of polyethylene/clay nanocomposite drawn fibres, also in the presence ofcompatibilizer, such as a commercial maleic anhydride grafted polyethylene, PEgMA, was studied. In the isotropic state both systems show intercalated morphology.After spinning and cold drawing, by adding the nanoparticles, the tensile strength as a function of the draw ratio increases and this rise is more pronounced for the filled compatibilized system. The reduction of the elongation at break, on the contrary, is about the same for all the examined samples. The orientation of the macromolecules, evaluated by measurements of the birefringence and calorim…

Effect of reprocessing on the properties of Polyethylene/cloisite 15A nanocomposites

Effetto della degradazione di un'argilla organicamente modificata sulle proprietà di nanocompositi a base di miscele PA6/HDPE

Morphology Modification of Polyethylene/Clay Nanocomposite Samples under Convergent Flow

The morphology of PE/CL nanocomposite samples subjected to convergent flows is studied. Elongational flow – the typical flow involved in spinning and film-blowing processing operations – significantly increases with the reduction of the capillary diameter. The values of the convergent extensional stress (calculated by Cogswell's formula) for the PE/CL systems, for all the adopted capillary geometries, are greater than the calculated values for pure polyethylene. The applied convergent flow, at the entrance of the capillary, is able to change the clay morphology and consequently the final material properties on the PE/CL system with limited affinity between the matrix and organo-modified cla…

Influence of Calcium Carbonate Nanoparticles on the Soil Burial Degradation of Polybutyleneadipate-Co-Butylenetherephthalate Films.

A polybutyleneadipate-co-butylenetherephthalate (PBAT) sample, commercially known as Ecoflex®, was processed via melt extrusion with CaCO3 nanoparticles coated with a hydrophobic coating. Blown films of PBAT and two composites with nanofiller (2% and 5%wt) were prepared and degradation tests in soil at 30 °C up to 180 days were carried out with weight loss measurements. Furthermore, biodegradation test according to ISO 14851 was carried out at 30 °C. The effect of CaCO3 on soil burial degradation was assessed by surface wettability and SEM. ATR-FTIR and XPS analyses highlighted chemical modifications induced by soil degradation. CaCO3 nanoparticles decreased surface wettability …

Effect of ultraviolet and moisture action on biodegradable polymers and their blend

In this work, the suitability of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT) and PBAT/PLA blend samples to outdoor applications were investigated in terms of mechanical, morphological and visual properties in presence of ultraviolet action and water, finding that PLA in particular can be actually considered for such applications.

Photochemical behaviour of PE/PA blends

Envirinmental-friendly design from renewable resources

Compositi polimerici biodegradabili con fibre di kenaf

Photo-Re-Stabilization of Recycled Post-Consumer Films for Greenhouses

On the Preparation and Characterization of Polyethylene/Polyamide Blends by Melt Processing in the Presence of an Ethylene/Acrylic Acid Copolymer and of New Phosphazene Compounds

Samples of HDPE and PA6 have been melt-processed in the presence of two new phosphazene compounds, CP-2EPOX and CP-20XA together with an ethylene/acrylic acid copolymer. The blends have been prepared in an industrial twin-screw extruder by using PA6 and PE in weight ratios of 25/75 and 75/25. When used, 5 phr of EAA and 0.2 phr of CP have been added. The materials have been completely characterized from a rheological, morphological, and mechanical point of view. The results indicate that the additives used caused an increase in the rupture tensile properties, of the impact strength and viscosity especially in the PE-rich blend in the presence of CP-2EPOX. This result can be attributed both …

Photooxidation Behavior of a LDPE/Clay Nanocomposite Monitored through Creep Measurements

Creep behavior of polymer nanocomposites has not been extensively investigated so far, especially when its effects are combined with those due to photooxidation, which are usually studied in completely independent ways. In this work, the photooxidation behavior of a low density polyethylene/organomodified clay nanocomposite system was monitored by measuring the creep curves obtained while subjecting the sample to the combined action of temperature, tensile stress, and UV radiation. The creep curves of the irradiated samples were found to be lower than those of the non-irradiated ones and progressively diverging, because of the formation of branching and cross-linking due to photooxidation. …

Rheology of poly(ethylene)-based nanocomposite films for agricultural applications

On the use of natural organic materials as fillers for recycled post-consumer plastices

Effect of C18 amine modifiers on the properties of LDPE-Montmorillonite nanocomposites

Proprietà meccaniche di composti poliolefinici caricati con riempitivi organico-natural: utilizo di promotori di adesione

Non-linear viscoelastic behavior of polymer melts interpreted by fractional viscoelastic model

Very recently, researchers dealing with constitutive law pertinent viscoelastic materials put forward the successful idea to introduce viscoelastic laws embedded with fractional calculus, relating the stress function to a real order derivative of the strain function. The latter consideration leads to represent both, relaxation and creep functions, through a power law function. In literature there are many papers in which the best fitting of the peculiar viscoelastic functions using a fractional model is performed. However there are not present studies about best fitting of relaxation function and/or creep function of materials that exhibit a non-linear viscoelastic behavior, as polymer melt…

The Use of Waste Hazelnut Shells as a Reinforcement in the Development of Green Biocomposites.

Biodegradable Mater-Bi (MB) composites reinforced with hazelnut shell (HS) powder were prepared in a co-rotating twin-screw extruder followed by compression molding and injection molding. The effects of reinforcement on the morphology, static and dynamic mechanical properties, and thermal and rheological properties of MB/HS biocomposites were studied. Rheological tests showed that the incorporation of HS significantly increased the viscosity of composites with non-Newtonian behavior at low frequencies. On the other hand, a scanning electron microscope (SEM) examination revealed poor interfacial adhesion between the matrix and the filler. The thermal property results indicated that HS could …

Kenaf-filled biodegradable composites: rheological and mechanical behaviour

Compositi Verdi: Miscele Post-Consumo Polietilene/Polipropilene con Fibre di Legno

Un nuovo strumento per misurare il comportamento al creep in condizioni reali di sistemi polimerici

Nanocomposites based on polystyrene and POSS molecules: properties and photo-stability

Photo-re-stabilization of recycled post-consumer films from greenhouses

Procedimento per la produzione di carboni attivi e attrezzatura per attuare il procedimento

Accelerated weathering of PP based nanocomposites: Effect of the coupling agent

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Eco-compositi a base di polietilene riciclato

CHARACTERIZATION OF BIOPOLYMER BASED COMPOSITES FILLED WITH WOOD FLOUR.

Sistema biocompatibile di supporto per la piantumazione di organismi vegetali in ambiente marino

Il brevetto consiste in un sistema a basso impatto ambientale, realizzato interamente in bioplastica, per il fissaggio sul fondo marino in forma rapida ed efficace di organismi vegetali, allo scopo di garantirne l'attecchimento e la crescita, assecondandone la dinamica naturale di sviluppo.

Caratterizzazione di nanocompositi polietilene/carbonato di calcio

Compression and injection molding of recycled polyethylene for greenhouses in presence of the natural fibres

Preparazione e lavorabilità per estrusione e stampaggio ad iniezione di PLA

Lavorazione e proprietà meccaniche del polipropilene con cariche organiche

Understanding the physical and/or chemical interaction in POSS-poly(ethylene-co-acrylic acid) nanocomposites

Nanocompositi a base di miscele compatibilizate PA6/PE: effetto della degradazione del modificante organico dell'argilla

Investigation on the Properties and on the Photo-Oxidation Behaviour of Polypropylene/Fumed Silica Nanocomposites

This work investigates the effects of very small amounts of fumed silica on the morphology and on the rheological and mechanical behaviour of polypropylene nanocomposites and on their photo-oxidation behaviour. Polypropylene nanocomposites were prepared using a twin-screw corotating extruder with 0, 1 and 2 wt/wt% of SiO2. Morphological, mechanical, thermomechanical and rheological properties were examined. It was found that the viscosity of the matrix is reduced by the presence of the silica nanoparticles, suggesting a poor adhesion between the two phases and probably some lubricating effect. On the contrary, the mechanical and, in particular, the thermomechanical properties of the matrix …

Seconda persona

The text aims at analyzing the theoretical nexus between Lacanian Psychoanalysis and Theories of Enunciation.

Structure–Property Relationships in Bionanocomposites for Pipe Extrusion Applications

In this work, bionanocomposites based on different biodegradable polymers and two types of nanofillers, namely a nanosized calcium carbonate and an organomodified nanoclay, were produced through melt extrusion, with the aim to evaluate the possible applications of these materials as a potential alternative to traditional fossil fuel-derived polyolefins, for the production of irrigation pipes. The rheological behavior of the formulated systems was thoroughly evaluated by exploiting different flow regimes, and the obtained results indicated a remarkable effect of the introduced nanofillers on the low-frequency rheological response, especially in nanoclay-based bionanocomposites. Conversely, t…

A Green Approach for Recycling Compact Discs

Compact discs (CDs) and digital versatile discs (DVDs) are mainly made by polycarbonate disc, a thin layer of aluminum or silver, a thin layer of a coating and a thin layer of a label of paper or PET. The recycling of these discs is difficult due to the removal of these non-polymeric layers and to our best knowledge, no industrial plants have been resent for their recycling. In this work, we propose a facile way to remove the non-polymeric layers and investigate the effect of the repetitive extrusion process on the processability and on the mechanical properties of the recycled polycarbonate. A few works have been published dealing with both the removal of the non-polymeric layers and the m…

Photo-oxidation behaviour and morphology of zinc oxide-poss polystyrene based nanocomposites

Polysemy and gestaltist computation. some notes on gestaltist compositionality

The paper is devoted to the concept of Gestaltist Compositionality. It is divided into two parts. The first part will introduce a minimal definition of «Gestaltist Compositionality». Moreover, it will prove that the computations implemented by this model of compositionality are sufficiently flexible to ensure the presence of several orders of semantic determination. The second part will be devoted to an investigation of the consequences of this result with particular reference to the identification of some versions of compositionality which relax the condition of semantic atomism without weakening the links of determination between understanding of the compounds and understanding of the com…

Morphology of nanocomposites from ethylene-acrylic acid copolymers

AbstractNew nanocomposites have been prepared by melt-compounding from commercial ethylene-acrylic acid copolymers (EAA) of different molar mass, molecular structure (branched or linear) and AA concentration, and a Zn-ionomer, with three commercial clays containing different proportions of the same organic modifier (dimethyldi(hydrogenated tallow)ammonium ion). Their morphology has been preliminarily investigated by X-ray scattering and transmission electron microscopy. The nanocomposites showed disordered intercalated morphology, with an expansion of the average gallery height, which appears to depend quite strongly on the molecular architecture of the EAA, whereas the other investigated v…

Proyectar para el ambiente

An Overview of Functionalized Graphene Nanomaterials for Advanced Applications

Interest in the development of graphene-based materials for advanced applications is growing, because of the unique features of such nanomaterials and, above all, of their outstanding versatility, which enables several functionalization pathways that lead to materials with extremely tunable properties and architectures. This review is focused on the careful examination of relationships between synthetic approaches currently used to derivatize graphene, main properties achieved, and target applications proposed. Use of functionalized graphene nanomaterials in six engineering areas (materials with enhanced mechanical and thermal performance, energy, sensors, biomedical, water treatment, and c…

Evolution of the morphology and characterzation of compatibilized PBT/EVA blends prepared by reactive extrusion

In this work, the possibility of preparing compatibilized blends of poly(butylene terephthalate) (PBT) and an ethylene vinyl acetate (EVA) copolymer by reactive extrusion in the presence of an ethylene acrylic acid copolymer (EAA) and a bisoxazoline compound (PBO) as compatibilization promoters has been studied. In addition, the evolution of the morphology of the blends under different annealing conditions in the presence and absence of the compatibilizing promoters has been studied. Binary blends of PBT and EVA showed behavior typical of incompatible blends with a gross morphology and bad mechanical performance. The situation was however different for ternary PBT/EVA/EAA and especially for…

Recycling of a Biodegradable Polymer Blend

Mechanical recycling is one of the possible ways to enhance the value of postconsumer plastic materials. However, the final performance of the recycled material will strongly depend on the quality of the selection made on the recycled product and on the degradation of the properties. In this context, the present study examines the effect of reprocessing for five successive extrusion cycles on the rheological, mechanical and thermal properties of a poly(butylene adipate-co-terephthalate) (PBAT)-based blend on samples reprocessed in both dry and wet conditions. The results showed that when the sample was processed after drying, degradation of the material was less than when it was processed i…

Natural anti-oxidant additives for bio-degradable polymers

Injection Molding and Mechanical Properties of Bio-Based Polymer Nanocomposites

The use of biodegradable/bio-based polymers is of great importance in addressing several issues related to environmental protection, public health, and new, stricter legislation. Yet some applications require improved properties (such as barrier or mechanical properties), suggesting the use of nanosized fillers in order to obtain bio-based polymer nanocomposites. In this work, bionanocomposites based on two different biodegradable polymers (coming from the Bioflex and MaterBi families) and two different nanosized fillers (organo-modified clay and hydrophobic-coated precipitated calcium carbonate) were prepared and compared with traditional nanocomposites with high-density polyethylene (HDPE…

Recycling of RPE/ Ground Tire Rubber Blends: Properties and Applications

Re-gradation of Photo-oxidized Post-consumer Greenhouse Films

The degradation undergone by the polymers during their use and because of the thermo-mechanical degradation undergone during the reprocessing operations provokes, among other effects, the decrease of the molecular weight. The change of the molecular architecture is responsable for the deterioration of all the properties. In order to restore the properties of post-consumer recycled plastics, some rebuilding of the molecular structure is necessary. In this work, photo-oxidized films for greenhouses were reprocessed in presence of additives able to react with the polyethylene in order to form branching and cross-linking, improving the properties of these post-consumer plastic.

Effect of thermal cycles on the rheological behaviour of polymerclay nanocomposites

Il ruolo di molecole POSS(polyhedral oligomeric silsesquioxane) sulle relazioni proprietà struttura nei nanocompositi a base polistirenica

Presenza di PLA nel riciclo di PET

Effects of organoclay on morphology and properties of nanocomposites based on LDPE/PA-6 blends without and with SEBS-g-MA compatibilizer

LDPE/PA-6 blends (75/25 wt/wt) were added with SEBS-g-MA (S) and/or an organoclay (20A) using different compounding sequences and the morphology and the properties of the blends or composites were investigated. An XRD study of the nanocomposites with pure polymers showed that 20A is intercalated by LDPE or PA-6 chains, whereas it is exfoliated by S if the clay concentration does not exceed 10 wt%. The SEM investigation showed that both S and 20A behave as efficient emulsifying agents for the LDPE/PA-6 blends. However, their effect on the mechanical properties was found to be opposite: S enhanced toughness but lowered the stiffness, whereas 20A improved the elastic modulus but impaired the i…

Green Composites of Biodegradable Polymers and Natural Organic Fillers

The role of filler type in the photo-oxidation behaviour of micro- and nano-filled polypropylene

The rising interest in polymer nanocomposites leads also to an increasing concern for their photo-oxidation resistance. The main properties and photo-oxidation behaviour of polypropylene-based microcomposites and nanocomposites were investigated. The results show that the use of nanosized calcium carbonate may lead to a higher photo-oxidation rate than that of pristine polypropylene, in a way that is comparable to organo-modified nanoclays. It is also observed that nanosized calcium carbonate causes higher photodegradation rates than microsized calcium carbonate. The main reasons for the increased photo-oxidation rates when using organo-modified nanoclays include the presence of iron ions, …

Toward the Decarbonization of Plastic: Monopolymer Blend of Virgin and Recycled Bio-Based, Biodegradable Polymer.

Decarbonization of plastics is based on two main pillars: bio-based polymers and recycling. Mechanical recycling of biodegradable polymers could improve the social, economic and environmental impact of the use of these materials. In this regard, the aim of this study was to investigate whether concentrations of the same recycled biopolymer could significantly affect the rheological and mechanical properties of biodegradable monopolymer blends. Monopolymer blends are blends made of the same polymers, virgin and recycled. A sample of commercially available biodegradable blend was reprocessed in a single-screw extruder until two extrusion cycles were completed. These samples were exposed to gr…

Effect of thermal treatment time on the rheological behaviour of PE based nanocomposites

“Compatibilization” through Elongational Flow Processing of LDPE/PA6 Blends

Polyamide/polyolefin blends have gained attention from the academia and the industry for several years. However, in order to optimize their properties, some drawbacks such as chemical incompatibility must be adequately overcome. This can be done by adding suitable compatibilizers. On the other hand, it is less known that suitable processing techniques may also lead to significant results. In a previous work on a low-density polyethylene/polyamide 6 (LDPE/PA6) blend, we found that the orientation due to elongational flow processing conditions could lead to an unexpected brittle&ndash

Preparazione e caratterizzazione di polimeri biodegradabili caricati con riempitivi organico-naturali

On the Improvement of the Processability of UHMW-HDPE by Adding a Liquid Crystalline Polymer and a Fluoroelastomer

Ultra-high molecular weight polyethylene possesses many interesting properties but a very bad processability. This material is not usually processed in conventional devices but only by compression moulding and RAM extrusion. Low molecular weight polyethylene can be used to improve the processability. In this work small amounts of a fluoroelastomer and of a liquid crystalline polymer have been used as processing aids to improve the extrudability of this polymer. In fact, the die pressure decreases whereas the output flow rate slightly increases with increasing concentration of the processing aids. Solution viscosity data shows that reduction of the mechanical stress during extrusion decrease…

PREPARATION AND CHARACTERIZATION OF CLAY NANOCOMPOSITES BASED ON COMPATIBILIZED POLYAMMIDE6/POLYETHYLENE BLENDS

Invecchiamento naturale e durabilità dei materiali polimerici

Effect of biobased plasticizers, used as dispersing aids, on mechanical, rheological and thermal properties of micro fibrillated cellulose (MFC)/poly (lactic acid) (PLA) biocomposites over the time: how MFC controls the plasticizer migration?

Micro Fibrillated Cellulose (MFC) has gained interest both in academia and industry, but some critical issues must be overcome to exploit the industrial MFC/biocomposites uses. In particular, the first drawback is related to the MFC agglomeration during the primary processing. Encouraging results have been obtained using plasticizers, as dispersing aids, during the extrusion that optimizes the process parameters based on the variation of the melt viscosity. However, even if the plasticizer addition counterbalances the excessive biocomposite stiffness, caused by the addition of the MFC, its eventual migration from the finished product needs to be evaluated to avoid toughness reductions as we…

Patent number PA2010 A 000023: Sistema biocompatibile di supporto per la piantumazione di organismi vegetali in ambiente marino

Il brevetto consiste in un sistema a basso impatto ambientale, realizzato interamente in bioplastica, per il fissaggio sul fondo marino in forma rapida ed efficace di organismi vegetali, allo scopo di garantirne l'attecchimento e la crescita, assecondandone la dinamica naturale di sviluppo.

The role of the clay in morphology modification of the uncompatible polymer blends

Testing of a kinetics equation of mechanical degradation

A modification of the kinetics equation of mechanical degradation of Harrington and Zimm is proposed to fit experimental data taken on a molten polystyrene. This equation is applied to each molecular weight of the discretized molecular weight distribution curve, and the limiting molecular weight is determined for each molecular weight. With this modification the theoretical curves fit both Mw and Mn curves well.

Effect of the elongational flow on the morphology and on the properties of polyethylene based nanocomposites

Lavorazione e proprietà meccaniche di polipropilene con cariche organiche

Role of oxygen on rheological response of polyethylene–clay nanocomposites to annealing

Photo-oxidation of polyolefin/clay nanocomposite films: role of organoclay and matrix type

Rheological and mechanical properties of biodegradable nanocomposites

Polymer nanocomposites have gained huge interest over the last decade. However, traditional thermoplastic nanocomposites do not match the rising concern about environmental issues. Therefore, during the last years, the search for biodegradable polymer nanocomposites is gaining importance. Most of biobased (i.e. based on biodegradable/bioderived polymer matrices) nanocomposites have poly(lactic acid), PLA, as matrix. However, it is of clear interest to take into account also different biobased polymer matrices, such as MaterBi. In this work, we prepared bionanocomposites containing MaterBi or a PLA-based polymer matrix, with two different kinds of nanofillers (organomodified clay and nanosiz…

Antimicrobial activity of EVA blown films containing nisin

Influence Of Clay Thermal Degradation On Polyethylene Based Nanocomposite

Imballaggi antimicrobici estrusi

Fracture behavior and mechanical, thermal, and rheological properties of biodegradable films extruded by flat die and calender

The development of biodegradable materials for tailored applications, particularly in the field of polymeric films and sheets, is a challenging technological goal as well as a contribution to help protect the environment. Poly(lactic) acid (PLA) is a promising substitute for several oil-based polymers; however, to overcome its thermal and mechanical drawbacks, researchers have developed solutions such as blending PLA with polybutylene adipate terephthalate (PBAT), which is capable of increasing the ductility of the final material. In this study, PLA/PBAT binary blends, with minimum possible content of nonrenewable materials, were examined from processing, thermal, morphological, and rheolog…

Processability and Properties of Re-Graded, Photo-Oxidized Post-Consumer Greenhouse Films

The recycling of post‐consumer plastics leads, in general, to secondary materials having properties worse than those of the reclaimed material and certainly worse than those of the same virgin polymer. This is because of the degradation undergone by the objects during their use and because of the thermo‐mechanical degradation undergone during the reprocessing operations. The change of the molecular architecture is responsible for this worsening of properties. The use of stabilizing systems can slow the degradation during the melt processing but cannot give any improvement of the final properties of the material. In order to enhance the properties of the recycled plastics, some rebuilding of…

Nanocompositi a base polimerica e molecole POSS: comportamento reologico e proprietà fisiche

Nanocomposites based on PS, PE, or ethylene-acrylic acid (ESCOR 5001) and POSS (Polyhedral oligomeric SilseSquioxanes) molecules were prepared by melt mixing. The nanocomposites’s structure-property relationships were analyzed mainly by rheological investigations and the variations with respect to the matrices were highlighted. The results of the rheological analysis show that the POSS molecules affect the properties in the molten state and act as plasticizer that is contrasted by the hydrogen bonds. The inorganic cage’s structure and the organic nature of the vertex groups of the molecules POSS play an important role in modulating the dispersion and in determining the final properties of t…

Synthesis and Characterization of a New Class of Fully Aromatic Liquid Crystal Polymers

Abstract A new fully aromatic LCP, obtained by polycondensation of N-(4-carboxyphenyl) trimellitimide and tert-butyl hydroquinone (FAPT), was previously described. The polymer shows very interesting physical and mechanical properties but a very high glass transition temperature which does not allow a good processability. In order to overcome this problem, a new class of LCPs, obtained by partial substitution of the dicarboxylic moiety with isophthalic acid, is described. The new thermoplastic materials were characterized from the physicochemical and mechanical point of view. All the polymers obtained with an isophthalic acid (FA-IA) content varying from 10 to 40% of the substituted moiety s…

Biocomposite PBAT/lignin blown films with enhanced photo-stability.

Lignin can be obtained as a byproduct during cellulose-rich pulp fibers production and it is habitually treated as waste or intended for low-value destinations. However, due to UV absorption and mechanical properties, lignin can contribute to the fabrication of biodegradable blown films with superior performances. In this study, it was established the suitability of lignin for manufacturing biocomposite PBAT blown films with higher stiffness and photo-oxidation resistance. The effect of the filler concentration on the melt rheological behavior in non-isothermal elongational flow was investigated. The results allowed us to choose the correct filler concentration for producing films through a…

Formulation of Agricultural Films by Using of the Recycled Polymers: Resistance to the Photoxidation

preparazione e caratterizzazione di nanocompositi polimero/CNTs sottoposti a stiro elongazionale

Lo scopo principale di questo lavoro è rivolto alla preparazione di sistemi polimero/CNTs (in particolare a 1 e 3 % in peso di CNTs) e alla caratterizzazione reologica e meccanica dei filamenti in funzione del rapporto di stiro.

Durability of biodegradable polymers for the conservation of cultural heritage

The use of polymers for conservation of cultural heritage is related to the possibility to slow down or stop natural deterioration which, in many cases, corresponds to stopping the entrance of liquid water and to favour spontaneous water vapour removal. Unfortunately, hydrophobicity is generally favoured by surface roughness and thus competitive with transparency. It is therefore important to find an optimal balance hydrophobicity, transparency and durability (especially to photooxidation). However, polymers typically used for applications in this field come from non-renewable resources and are not biodegradable. In this work, the mechanical, structural and optical properties of PLA, PBAT a…

Performances and morphology of polyamide/carbonaceous structures based fibers

In this work the influence of carbonaceous particles with different particle sizes and shapes on the morphology and mechanical performances of polyamide (PA) based fibers was investigated. Graphene nanoplatelets (GNP) are compared with spherical and rod-like carbon fillers such as carbon black (CB) and multiwall carbon nanotubes (MWCNT). The different morphologies of the particles control their dispersion and their alignment in PA fibers upon elongational flow action and play a key role in structure-property relationships.

Compatibilization of PBT/EVA blends

Eco-compositi a base di polietilene riciclato e riempitivi naturali

Ecocompositi polimeri caricati con riempitivi organico-naturali

Compression and injection molding of recycled polyethylene for greenhouses in presence of the natural fibers

Green Composites a base di materie plastiche post-consumo e cariche organiche naturali

On the use of natural organic materials as fillers for recycled post-consumer plastics

Rheological, mechanical and morphological characterization of monopolymer blends made by virgin and photo-oxidized polypropylene

In this work, monopolymer blends of virgin polypropylene and photo-oxidized polypropylene were prepare and characterized. The polypropylene samples were subjected to accelerated ageing to simulate the effects of outdoor exposure of polypropylene. After exposure, samples were pelletized and mixed with the same virgin polymer. The rheological, mechanical and morphological characterization was conducted on both the polymers and the blends. Both viscosity and mechanical properties decrease with increases in the content of recycled, photo-oxidized components and of the level of degradation of this component. In addition, the experimental data were compared with a model that takes into account bo…

UNEVEN DISTRIBUTION OF ORGANOCLAY IN HDPE/PA6 BLENDS - IMPACT OF MICROSTRUCTURE AND MECHANICAL BEHAVIOUR

Preparation and Characterization of Polyolefin-Based Nanocomposite Blown Films for Agricultural Applications

These kinds of filmshave,asaprimaryaim,tocreateafavorablemicro-climateto accelerate the plant growth.Thematerialsfortheseapplicationsmustpossessseveralspecificandpeculiarcharacteristics,suchastheabilitytobeshaped into films (even with wide dimensions and largethickness ranges), good deformability and tear resistancetogetherwithasufficientrigidity,transparencyforUVandIR radiation in particular regions of the spectrum, a goodresistance to photo-oxidative phenomena and for someapplications to provide a barrier for certain gases.Moreover, an important property requested for thematerials used for greenhouse covering is the capabilityto diffuse the light. In fact, according to some studies,diffused l…

Ecocompositi MaterBi (R)/Farina di legno: ottimizzazione delle proprietà attraverso analisi statistica

Effect of multiple reprocessing cycles on the properties of polyethylene/Cloisite 15A nanocomposites

Improving the mechanical properties of polyolefin-natural organic filler composites

Biodegradable polymer-wood flour composites: main properties and biodegradability

During the last years, a considerably increasing rate of attention has arisen on biodegradable polymers. In the meanwhile, the use of wood-plastic composites (WPC) has grown in importance, especially in the United States. The combination of biodegradable polymers and wood-based fillers allows obtaining the typical advantages achievable with the use of WPCs, with the further advantage of the biodegradability and compostability of the matrix (and not only of the filler). In this work, the characterization and the biodegradability assessment of Mater-Bi®-wood flour composites have been carried out.

Morphology and properties of LDPE/PA-6 blends compatibilized with SEBS-g-MA and/or organoclay

Effects of a new multifunctional additive on the thermo-stability, photo-stability and on the processability of the polyamide 6

The Nucleating Effect of a Semiflexible Liquid-Crystalline Polymer for the Crystallization of Poly(Phenylene Sulfide)

Abstract Blends of poly(phenylene sulfide) and a semiflexible liquid-crystalline polymer have been prepared, in the whole range of concentration, by melt mixing. The effect of the LCP phase on the crystallization of PPS has been studied by non-isothermal and isothermal calorimetry. It has been found that the addition of only 2-5% LCP into PPS strongly increases the crystallization rate of the latter polymer. This effect has been interpreted as the result of an increased nucleation density. The morphology of the blends, studied by scanning electron microscopy, has shown that the two polymers are incompatible, although the phase dispersion is good. Under elongational flow, the dispersed phase…

A facile and eco-friendly route to fabricate poly(Lactic acid) scaffolds with graded pore size

Over the recent years, functionally graded scaffolds (FGS) gaineda crucial role for manufacturing of devices for tissue engineering. The importance of this new field of biomaterials research is due to the necessity to develop implants capable of mimicking the complex functionality of the various tissues, including a continuous change from one structure or composition to another. In this latter context, one topic of main interest concerns the design of appropriate scaffolds for bone-cartilage interface tissue. In this study, three-layered scaffolds with graded pore size were achieved by melt mixing poly(lactic acid) (PLA), sodium chloride (NaCl) and polyethylene glycol (PEG). Pore size distr…

From Topology to Quasi-Topology. The Complexity of the Notional Domain

This article examines a fundamental metalinguistic construction of the theory of enunciative operations: the notional domain. In particular, we try to explain some elementary topological concepts on which this construction is based and we try to show the key role they play in the description of some basic linguistic operations.

Properties of recycled polyethylene/organic fillers green composites

Effects Of Adding New Low Molecular Weight Phosphazene Compounds To PBT/Ny Blends

Influenza di argille organomodificate su morfologia e proprietà di miscele polimeriche polietilene/poliammide

Recycling of heterogeneous plastics wastes: I—Blends with low-density polyethylene

Abstract Heterogeneous plastics wastes are usually recycled by means of ad hoc designed equipment which, in a single step, produces objects with large dimensions and poor mechanical properties. In this preliminary work, the possibility of preparing blends of plastics waste and low-density polyethylene is investigated. These ‘secondary’ materials (with plastics waste content up to 50%) show mechanical properties similar, except for the elongation at break, to those of the virgin polyethylene. The addition of moderate amounts of calcium carbonate does not significantly reduce the properties of these materials.

Mechanical, Thermomechanical and Reprocessing Behavior of Green Composites from Biodegradable Polymer and Wood Flour

The rising concerns in terms of environmental protection and the search for more versatile polymer-based materials have led to an increasing interest in the use of polymer composites filled with natural organic fillers (biodegradable and/or coming from renewable resources) as a replacement for traditional mineral inorganic fillers. At the same time, the recycling of polymers is still of fundamental importance in order to optimize the utilization of available resources, reducing the environmental impact related to the life cycle of polymer-based items. Green composites from biopolymer matrix and wood flour were prepared and the investigation focused on several issues, such as the effect of r…

The role of POSS on the structure-properties relationship in Polystyrene based nanocomposites

Miscele PE/PA6: transizione fragile-duttile indotta dall’orientazione

Interaction in POSS-poly(ethylene-co-acrylic acid) nanocomposites

Use of polyhedral oligomeric silsesquioxane (POSS) in polymer-based nanocomposites is promising for the design of high-performance materials for several applications. In this study, nanocomposites based on ethylene-acrylic acid (EAA) copolymer and POSS molecules were prepared by melt mixing. In particular, partial cage POSS with different pendent organic groups was used to investigate the interaction between the –OH groups of POSS and the acrylic functionalities of the matrix. All nanocomposites were characterized by mechanical, rheological, thermal and spectroscopic analyses. In addition, PE-POSS compounds were prepared under the same processing conditions for sake of comparison. The POSS …

Influenza del flusso convergente in sistemi nanocompositi a matrice polietilenica

Effect of adding new phosphazene compounds in polybutyleneterephthalate/polyamide blends. II: Effect of difefrent polyamides on the properties of extruded samples

Proprietà meccaniche di miscele poliammide/poliolefine in presenza di ciclofosfazeni

Polyethylene/clay nanocomposites with or without compatibilizer: effect of extensional flow

Photooxidation and stabilization of a solar cell encapsulating crosslinked EVA

Effect of different matrices and nanofillers on the rheological behavior of polymer-clay nanocomposites

In this work, a comprehensive study of the rheological behavior under shear and isothermal and nonisothermal elongational flow of low density polyethylene (LDPE) and ethylene-vinyl acetate copolymer (EVA) based nanocomposites was reported to evaluate their "filmability", that is, the ability of these material to be processed for film forming applications. The influence of two different kinds of organoclay - namely Cloisite 15A and Cloisite 30B - and their concentration was evaluated. The presence of filler clearly affects the rheological behavior in oscillatory state of polyolefin-based nanocomposites but the increase of complex viscosity and the shear thinning are not dramatic. A larger st…

Morphology and mechanical properties of extruded ribbons of LDPE/PA6 blends compatibilized with an ethylene-acrylic acid copolymer

Two grades of low density polyethylene (LDPE) were blended with polyamide-6 (PA) in the 75/25 and 25/75 wt/wt ratios and shaped into ribbons with a Brabender single screw extruder. An ethylene-acrylic acid copolymer (EAA) was used in the 2 phr concentration as a compatibilizer precursor (CP). The morphology of the ribbons and its evolution during high temperature annealing were investigated by scanning electron microscopy (SEM). The results confirmed that EAA does actually behave as a reactive compatibilizer for the LDPE/PA blends. In fact, in the presence of EAA, the interfacial adhesion is improved, the dispersion of the minor phase particles is enhanced and their tendency toward fibrilla…

Characterization of polyethylene/calcium carbonate nanocomposites

FLUSSO ELONGAZIONALE NON ISOTERMO DI POLIMERI BIODEGRADABILI

Design and Eco-design in wine industry

Thermomechanical Analysis of Isora Nanofibril Incorporated Polyethylene Nanocomposites

The research on cellulose fiber-reinforced nanocomposites has increased by an unprecedented magnitude over the past few years due to its wide application range and low production cost. However, the incompatibility between cellulose and most thermoplastics has raised significant challenges in composite fabrication. This paper addresses the behavior of plasma-modified polyethylene (PE) reinforced with cellulose nanofibers extracted from isora plants (i.e., isora nanofibrils (INFs)). The crystallization kinetics of PE&ndash

Organoclay Nanocomposites from Ethylene-Acrylic Acid Copolymers

A study of the structure–property relationships for nanocomposites prepared by melt compounding from ethylene–acrylic acid copolymers of varied composition and molecular architecture, and organoclays modified with different ammonium ions has been made by DSC, POM, SEM, TEM, WAXD, and rheological and mechanical tests. Within the series of clays investigated, the best levels of dispersion were displayed by those organically modified with quaternary ammonium ions containing two long alkyl tails. The relevant nanocomposites were shown to possess mixed exfoliated and intercalated morphology. The spacing of the intercalated clay stacks, most of which comprise few silicate layers, was found to be …

Anti-ossidanti naturali per polimeri biodegradabili

Effetto del flusso elongazionale sulle proprietà e sulla morfologia di filamenti di nanocomposito a base di polietilene e montmorillonite organo-modificata

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LDPE/EVA/Clay nanocomposites: prcessability and properties

Characterization and biodegradability of biodegradable polymer-wood flour composites

Reactive Compatibilization of PBT/EVA Blends with an Ethylene-Acrylic Acid Copolymer and a Low Molar Mass Bis-Oxazoline

Polyesters and polyolefins form highly incompatible blends with poor properties and gross morphology that hinder any practical applications. In this work, the possibility to compatibilize an incompatible blend of poly(butylene terephthalate) (PBT) with ethylene vinyl acetate (EVA) by adding a bis-oxazoline compound, 2,2'-(1,3-phenylene)-bis(2-oxazoline) (PBO), and an ethylene acrylic acid copolymer (EAA) as compatibilizer precursors has been studied. The results indicate that the binary uncompatibilized blends show poor mechanical properties and a bad morphology with scarce adhesion between the phases. The situation is only slightly improved when the EAA is added while the best performance …

Intercalation effects in LDPE/o-Montmorillonites nanocomposites

Abstract Typical montmorillonite clays (Cloisite ® Na + , Cloisite ® 30B) were modified by treatment with octadecyl ammonium chloride (ODC) and successive additions of octadecylamine (ODA). XRD analyses of the modified clays indicated an increase of the basal spacing of the (0 0 1) planes depending on the ODC or ODA additions. Nanocomposites were prepared by dispersing the modified clays (3% w/w concentration) in LDPE, using a Brabender mixer. XRD measurements of the obtained products indicated in some cases the achievement of intercalation effects, which were confirmed by TEM analysis. Some thermal, mechanical, dynamic-mechanical and rheological properties were evaluated and correlated to …

Rheological characterization of bio-degradable nanocomposites

On the role of extensional flow in morphology and property modifications of MWCNT/polyamide-based fibres

Unfilled and MWCNT-filled PA fibers are prepared and the effect of the extensional flow on their mechanical performance and morphological variations is investigated. Morphological analyses using SEM, TEM, and SAXS suggest a stronger orientation of the MWCNTs along the fiber direction with increasing extensional flow. A particular MWCNT bundle formation in the PA drawn nanocomposite fibers is observed for the first time, and a pull-out of the central nanotube in some bundles is noted. The maintenance of the “shish-kebab” structure upon extensional flow is responsible for the mechanical improvements and dimensional stability in MWCNT-filled PA fibers.

Effetto della filatura di un sistema polimerico biodegradabile nanocomposito

Photo-oxidation of nano- and micro-filled polypropylene

Attractors/Basin of Attraction

It is a controversial issue to decide who first coined the term “attractor”. According to Peter Tsatsanis, the editor of the English version of Prédire n’est pas expliquer, it was René Thom who first introduced such a term. It is necessary, however, to remember that Thom thought that it was first introduced by the American mathe- matician Steven Smale, “although Smale says it was Thom that coined the neolo- gism “attractor”“(Tsatsanis 2010: 63–64 n. 20). From this point of view, Bob Williams expressed a more cautious opinion by saying that “the word “attractor” was invented by these guys, Thom and Smale” (Cucker and Wong 2000: 183). But other mathematicians are of the opinion that the term …

The role of additives in the recycling of polymers

The main problems in post-consumer plastics recycling are due to the degradation undergone by the polymers during processing steps and by the products during their lifetime and, for heterogeneous recycling, to the incompatibility of different polymers. To reduce the negative effects of the recycling steps, two main ways can be adopted for homogeneous materials: restabilization during the recycling to avoid or at least to slow the degradation and addition of fillers and modifiers capable of improving the performance of thermoplastic polymers without increasing the final cost of the secondary material. In the case of mixed plastics, compatibilization is the necessary step to obtain secondary …

Influence of PLA on the recycling of PET bottles

Ecocomposites obtained from MaterBi(R) and lignocellulosic fillers

Effect of Different Matrices and Nanofillers on the Rheological Behavior of Polymer-Clay Nanocomposites

In this work, a comprehensive study of the rheologi-cal behavior under shear and isothermal and nonisothermal elongational flow of low density polyethylene (LDPE) and ethylene-vinyl acetate copolymer (EVA) based nanocomposites was reported to evaluate their "filmability", that is, the ability of these material to be processed for film forming applications. The influence of two different kinds of organoclay - namely Cloisite 15A and Cloisite 30B - and their concentration was evaluated. The presence of filler clearly affects the rheological behavior in oscil-latory state of polyolefin-based nanocomposites but the increase of complex viscosity and the shear thinning are not dramatic. A larger …

Properties and morphology of PA based filament loaded with MW-CNTs: effect of filler aspect ratio and surface functionalization

Oxazoline functionalization of polyethylenes and their blends with polyamides and polyesters

The compatibilization of blends of polyamide-6 (PA6) with linear low density polyethylene (LLDPE) and of poly(ethylene terephthalate) (PET) with high density polyethylene (HDPE), by functionalization of the polyethylenes with oxazoline groups was investigated. Chemical modification of LLDPE and HDPE was carried out by melt free radical grafting with ricinoloxazoline maleinate. Blends preparation was made either with a two-steps procedure comprising functionalization and blending, and in a single step in which the chemical modification of polyethylene with the oxazoline monomer was realized in situ, during blending. The characterization of the products was carried out by FTIR spectroscopy an…

Comparison of the Recycling Behavior of a Polypropylene Sample Aged in Air and in Marine Water

During the processing and during their lifetime, polymers are subjected to several environmental stresses—thermomechanical, photo-oxidative, etc.—that can strongly modify their chemical and molecular structure and, consequently, their morphology. Reduction of the molecular weight and formation of double bonds and oxygenated groups are the main changes observed as a consequence of the degradation. As a result of these changes, the macroscopic properties are dramatically modified. These changes can have a relevant effect if the post-consumer plastic manufacts are recycled. In this work, a sample of polypropylene subjected to two different degradation histories—photo-oxidatio…

Properties-morphology-processing relationships in polymer based clay nanocomposites

Photooxidation and Durability of PE Based Nanocomposites

Degradazione termomeccanica di nanocompositi a base poliolefinica

Nanocompositi e microcompositi: lavorabilità e proprietà meccaniche

BIODEGRADABLE BILAYER FILMS PREPARED BY CO-EXTRUSION

The sensitivity for reducing packaging waste drove academic and industrial efforts to search compostable or biodegradable bio-sourced polymeric materials. Multilayer systems represent a suitable strategy to obtain the required properties and to improve biopolymer performance. The aim of the current work is the coextrusion film blowing of a biodegradable bilayer film PLA/MaterBi with the purpose to overcome the drawbacks of the individual components.

Ruolo della reologia nelle evoluzioni morfologiche di miscele polimeriche immiscibili nano composite

Polymer blends can undergo, during processing, degradation phenomena because of the presence of both temperature and mechanical stresses. With respect to pure homogeneous polymers, the degradation of polymer blends shows distinct features because of the possible interaction between the different chemical species. These interaction can give rise to both a faster degradation or to the formation of copolymers which act as stabilizing agents. This latter phenomena is particularly important in the processing of condensation polymers

Polymer Processing and Performance: 2018–2019

The section “Polymer Processing and Performance” of Polymers has published, in the last two years, 175 high quality papers investigating the processing and properties of several polymer based systems [...]

Effect of nano zinc oxide as UV stabilizer on the weathering performance of wood-polyethylene composite

Abstract In this study, the effect of using nano-sized zinc oxide (ZnO) particles on the enhancement if the degradation resistance of wood-high density polyethylene (HDPE) composite was investigated through artificial weathering. Samples with different amounts of ZnO mixing ratio (0, 1, 2, and 4 wt%) were manufactured using an internal mixer followed by compression molding. The prepared samples were then exposed to the artificial weathering process in a QUV weatherometer. The weathering behavior of samples was characterized using tensile strength, contact angle analysis, colorimetry, ATR-FTIR spectroscopy and FE-SEM. The results indicated that the amount of surfaces crack, tensile strength …

CHARACTERIZATION AND PROCESSABILITY NOF POLYESTER BASED NANOCOMPOSITES

How the POSS molecules improve the UV stability of polystyrene based nanocomposites?

Degradation od Mater-Bi/wood flour biocomposites in active sewage sludge

Mechanical properties of recycled polyethylene ecocomposites filled with natural organic fillers

The use of natural organic fillers in addition to postconsumer recycled polymers is getting a growing interest during the last years; this is due to many advantages they can provide in terms of cost, aesthetic properties, environmental impact. In this work, several types of wood flour (differing each other with regard to production source and particle size) were added to a recycled polyethylene coming from films for greenhouses and the effects of filler type, content, and size were investigated. Investigation was then focused on the improvement of mechanical properties, through the addition of polar copolymers (ethylene-co-acrylic acid, ethylene-vinyl acetate) and a maleic anhydride-grafted…

Morphology and properties of polyolefin/clay nanocomposites drawn fibers

Effetto dei cicli di lavorazione sulle proprietà di nanocompositi PE/Cloisite 15A

Characterization of green composites from biodegradable polymers and wood flour.

Processing and properties of blends with liquid crystal polymers

Experimental data on the processing behavior and on the rheological and mechanical properties of blends with a liquid crystal polymer as one component are presented. The blends with low amounts of LCP show easier processability and lower viscosity than the thermoplastic matrix. The elastic modulus is also improved. The reduction of viscosity has been attributed to the lower pressure entry, due to the formation of fibrils and to the immiscibility of the two phases.

Rheological Response of Polyethylene/Clay Nanocomposites to Annealing Treatment

The rheological response of a polyethylene/clay nanocomposite to annealing treatment under air and nitrogen atmospheres was studied. The treatment influences the rheology of the nanocomposite significantly. In particular, the viscosity and the non-Newtonian behavior dramatically increase with annealing time, and a liquid-like/solid-like transition is observed. The annealed samples were characterized by ATR-FT-IR spectrometry and it was shown that a silicate-rich layer is formed on the surface of the nanocomposite. This result was confirmed by TEM images of bulk and surface of annealed samples. It was demonstrated that the formation of this coating is the main cause of the change of rheologi…

Morphology of Polyamide/Polyethylene Blends in Presence of Nanoclay

Utilizzo di materiali riciclati per la produzione di film agricoli per copertura: resistenza alla foto-ossidazione

Kenaf-filled biodegradable composites: rheological and mechanical behaviour

Biodegradable polymer composites, typically based on biodegradable polymer matrices and natural-organic fillers, are gaining rising interest and importance over the last few years. Several natural-organic fillers can be used but the most widespread so far is wood, in the form of fibres or flour. Alternative cellulosic fillers can ensure advantages in terms of resource utilization and properties of the final composite. In this work, Mater-Bi® based biodegradable composites were prepared with two kinds of wood flour, and directly compared with alternative composites containing kenaf fibres. The use of kenaf fibres allowed improved elastic modulus, tensile strength and interaction with the pol…

Effect of annealing under different atmospheres on polyethylene-clay nanocomposites

Effect of an organoclay on the photochemical transformations of a PBAT/PLA blend and morpho-chemical features of crosslinked networks

Abstract In this work, we report the effect of an organoclay on the photochemical weathering of nanocomposites based on a poly(butylene adipate-co-terephthalate) (PBAT)/poly(lactic acid) (PLA) blend. The evolution of physicochemical properties was monitored by integrating spectroscopic, mechanical, and morphological analyses. A robust relationship was found between the molecular transformations of the polymer macromolecules and the morpho-mechanical properties of irradiated films. Moreover, the analysis of insoluble fractions extracted from nanocomposites pointed out that free-standing, porous structures, displaying an unprecedented thickness as great as 100 µm, were formed, thus unambiguou…

A model for the prediction of the flow curves from interlayer distance and vice versa for intercalated polymer and polymer blend nanocomposites

In this work was proposed a simple model to predict the viscosity and the power law index from the interlayer distance and, vice versa, the interlayer distance from a single flow curve for intercalated polymer nanocomposites. This model cannot be applied to exfoliated nanocomposites or when other interactions are present in the systems.

Characterization of biobased composites filled with wood flour

Effect of the processing on polyethylene/clay nanocomposites

Photo-degradation behaviour of OMMT-filled PE/PA blends: improvement of the photo-resistance through morphology modification

Photo-Oxidative and Soil Burial Degradation of Irrigation Tubes Based on Biodegradable Polymer Blends

: Irrigation tubes based on biodegradable polymers were prepared via an extrusion-drawing process by Irritec and compared to conventional pipes made of high-density polyethylene (HDPE). A commercial polylactide/poly (butyleneadipate-co-butyleneterephthalate) (PLA/PBAT) blend (Bio-Flex&reg

Compatibilization of Polypropylene/Polyamide 6 Blend Fibers Using Photo-Oxidized Polypropylene.

The use of polyamide/polyolefin blends has gained importance and concern for years, but they also show some issues to be adequately addressed, such as the incompatibility between the two components. This is usually overcome by using suitable compatibilizers, typically based on functionalized polyolefins. However, there is only little information about the use of a degraded polyolefins to induce compatibilization. This is even truer, as far as polyamide 6/polypropylene (PA6/PP) blends are concerned. In this work, compatibilization of PA6/PP blends by using small amounts of photo-oxidized PP was investigated

On the photo-oxidation behaviour of nano-filled polypropylene: role of the filler type and compatibilizer

Utilisation of polyhydroxyalkanoates for biodegradable polymer blends: properties and application

Clay nanocomposites based on compatibilized PA6/HDPE blends

Du potentiel sémantique au signifié dialogique. Refléxions sur la construction énonciative du sens

La notion de potentiel sémantique est très souvent invoquée au fin d’expliquer certaines propriétés constitutives des principales opérations mobilisées par l’activité de langage dans la construction énonciatives du sens. De nombreux chercheurs appartenant à des écoles linguistiques différentes ont réfléchi de manière systématique sur le statut épistémologique de cette notion: des travaux de B. Victorri sur la compositionnalité gestaltiste du sens jusqu’aux travaux de J. Allwood et P. Linnel sur la fondation cognitive d’une véritable épistémologie dialogique du langage, on retrouve traces de cette notion dans plusieurs domaines théoriques différentes. Les objectifs de ce paper seront multipl…

Compositi polimerici con riempitivi organico-naturali

Effect of annealing under different atmospheres on polyethylene-clay nanocomposite

Quarry Limestone Dust as Fine Aggregate for Concrete

In quarrying activities, rock is extracted and transformed into aggregate of various sizes for civil engineering applications. In this process waste, fine aggregates is generated. The disposal of this type of waste is a further cost in the extraction process, but also a possible cause of environmental degradation and pollution (e.g. leaching into water reserves, atmospheric pollution as a result of small particles causing respiratory diseases or deposited on plants disrupting photosynthesis, affecting aquatic habitats, etc.). A strategy for the effective recycling of quarry dust, not only reduces waste generation and disposal but also addressed protection of the environment. The Italian qua…

Foto-ossidazione di film nanocompositi a base LDPE/EVA

Morphology, rheology, and mechanical properties of a new nanobiocomposite

Nanobiocomposites are a new class of biodegradable polymer materials with an ultrafine phase dispersion of the order of a few nanometers in a biodegradable polymer matrix that shows very interesting properties often very different from those of conventional filled polymers. In this work the morphology and the rheological and mechanical properties of a new nanobiocomposite made of a biodegradable copolyester based blend with an organomodified montmorillonite have been investigated to evaluate its possible use in several applications. SAXS diffractograms and TEM micrographs show that the in both the adopted processing conditions an hybrid intercalated/exfoliated morphology is observed. Rheolo…

Regradation of Photooxidized Post-Consumer Greenhouse Films

Gas Barrier, Rheological and Mechanical Properties of Immiscible Natural Rubber/Acrylonitrile Butadiene Rubber/Organoclay (NR/NBR/Organoclay) Blend Nanocomposites

In this paper, gas permeability studies were performed on materials based on natural rubber/acrylonitrile butadiene rubber blends and nanoclay incorporated blend systems. The properties of natural rubber (NR)/nitrile rubber (NBR)/nanoclay nanocomposites, with a particular focus on gas permeability, are presented. The measurements of the barrier properties were assessed using two different gases—O2 and CO2—by taking in account the blend composition, the filler loading and the nature of the gas molecules. The obtained data showed that the permeability of gas transport was strongly affected by: (i) the blend composition—it was observed that the increase in acrylonitrile butadiene rubber compon…

Polymer mechanical recycling: downcycling or upcycling?

Recycled plastics are considered as materials with physical, mechanical and aesthetic properties worse than the virgin ones. In fact, this is true because degradation during lifetime and during the recycling operations changes the structure and the morphology of the polymers and then the final properties of the secondary material. Several “strategies” are under investigation, and in some cases also applied, in order to avoid further degradation during recycling and, if possible, to repair the macromolecules broken during lifetime and then to restore or to improve the initial properties. In this paper the more important techniques, already used in industry or under investigation, according …

Modification of EVOH copolymers with e-caprolactone: synthesis and compatibilization effects in PE/PVC blends

Polyethylene-polycaprolactone graft copolymers with different chemical structures (i.e. different number and length of PCL grafts and molecular weight of PE backbone) were synthesized from various EVOH copolymers and e-caprolactone, using Aluminum isopropoxide as catalyst, and were tested for their compatibilizing capability in PE/PVC blends. PE and PCL segments in the graft copolymers were found completely immiscible, while PCL segments of the graft copolymers were found completely miscible with PVC. When graft copolymers were added to PE/PVC blends they proved to be good agents for the dispersion of PVC phase in the PE matrix. SEM showed also improved adhesion between the dispersed PVC ph…

Rheological Properties of Different Film Blowing Polyethylene Samples Under Shear and Elongational Flow

Summary: The rheological behavior of polyethylenes ismainly dominated by the molecular weight, the molecularweight distribution and by the type, the amount and thedistribution of the chain branches. In this work a linearmetallocenecatalyzedpolyethylene(m-PE),abranchedme-tallocene catalyzed polyethylene (m-bPE), a conventionallinear low density polyethylene (LLDPE) and a low densitypolyethylene (LDPE) have been investigated in order tocompare their rheological behavior in shear and in elonga-tional flow. The four samples have similar melt flow indexand in particular a value typical of film blowing grade.The melt viscosity has been studied both in shear and inisothermal and non-isothermal elonga…

Characterization of annealed LDPE/clay nanocomposites

Effect of reprocessing on polyamide/polyolefin based nanocomposites

Photochenical behaviour of PE/PA polymer blends

EVA Copolymer Based Nanocomposites: Rheological Behavior Under Shear and Isothermal and Non-Isothermal Elongational Flow

Formulazione e Caratterizzazione dei “Compositi verdi” a Base di Materie Plastiche Post-Consumo e Cariche Organiche

Nanocomposites from Poly(Ethylene-co-Acrylic Acid) Copolymers and a Zn-Ionomer

EVA Copolymer Based Nanocomposites: Rheological Behavior Under Shear and Elongational Flow

Film blowing and characterization of PA6/LDPE blends