Search results for "Thermoplastic"

MULTI AXIAL TESTING OF ADHESIVELY BONDEDJOINTS OF FIBER REINFORCED THERMOPLASTIC POLYMERS

2015

International audience; In order to predict the mechanical behaviorof adhesively bonded joints, it is necessary to develop robust numerical models.This robustness is only reached if an extensive experimental database with tensile, shear and complex combined peel and shear loads can beestablished. The purpose of this study is to present a multi axialdevice for testing adhesively bonded joints, using KS2-type specimens traditionally utilized for spot-weld characterization. The tests were conducted on a glass fiber reinforced thermoplastic polymer(PA6-6) composite adhesively bonded with a flexible polyurethane adhesive. This adhesive/substrate combination allowsshort process times and good per…

Aroma compound transfer between a solid food matrix and packaging films: a comprehensive approach

2008

International audience; Food quality is highly dependent on mass transfers occurring in food / packaging systems during storage. Particularly, aroma compound transfers are influenced by the composition and structure of the packaging and food matrix, the physico-chemical properties of aroma compounds and the conditions of the external environment (1). The influence of the food matrix on aroma compound-packaging film interactions was little studied in the literature (2,3). The objective of this work, in the framework of the French project CANAL ARLE, is to better understand aroma compound transfer into and through cellulosic and thermoplastic packaging films by taking into account their inter…

Conifer needles as thermoplastic composite fillers: structure and properties

2016

This study describes the properties of thermoplastic polymer composites based on polyethylene (of low and high density) and ethylene-propylene copolymers using various types of conifer needles (pine, spruce, fir, and cedar) as fillers. For the needles, thermogravimetric analysis (TGA) and TGA/Fourier transform infrared spectroscopy (TGA/FTIR) were performed to investigate their structures and thermal resistance, as required for the composite processing methods. Moreover, structural differences were studied for the analyzed fillers and composite materials (FTIR). The results were compared with the values obtained for composites with conifer wood flour. Composites with conifer needles (pine) …

Considering lithium-ion battery 3D-printing via thermoplastic material extrusion and polymer powder bed fusion

2021

Abstract In this paper, the ability to 3D print lithium-ion batteries through Pmnbspace thermoplastic material extrusion and polymer powder bed fusion is considered. Focused on the formulation of positive electrodes composed of polypropylene, LiFePO4 as active material, and conductive additives, advantages and drawbacks of both additive manufacturing technologies, are thoroughly discussed from the electrochemical, electrical, morphological and mechanical perspectives. Based on these preliminary results, strategies to further optimize the electrochemical performances are proposed. Through a comprehensive modeling study, the enhanced electrochemical suitability at high current densities of va…

Novel Polycaprolactone Nanocomposites Containing Thymol of Interest in Antimicrobial Film and Coating Applications

2008

It is well-known that the nanocomposites technology can significantly enhance, among others, the thermal, mechanical, and barrier properties of plastics. It is also known that most bioplastics, including the thermoplastic biopolymers, have lower than desired levels for certain properties which makes their use in certain packaging applications problematic. The combination of active technologies such as antimicrobials and nanotechnologies such as nanocomposites can synergistically lead to bioplastic formulations with balanced properties and functionalities for their implementation in packaging applications. The present work presents the development and characterization of novel nanocomposite…

Rheological and mechanical properties of biodegradable nanocomposites

2018

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…

Einfluss des polymerrückgrats auf eigenschaften von thermoplastischen elastomeren

1992

4-Urazoyl benzoic acid groups were statistically attached to various hydrocarbon elastomers, polar elastomers and partially crystalline polymers via a polymer-analogous reaction. DSC, FTIR, stress-strain experiments and dynamic-mechanical analysis were used to analyse whether these systems, analogous to functionalized polybutadienes, would form ordered supra-molecular structures of the polar side-groups that would lead to a thermoreversible crosslinking. While the structure formation is suppressed for elastomers with a large cross-sectional area of the chain (e.g. butyl rubber) or polar side-groups, (e.g. polychloroprene), the mechanical propertie can be controlled by balancing supermolecul…

1993

4-(4-Carboxyphenyl)-3,5-dioxo-1,2,4-triazolidin-1-yl moieties resulting from 4-(3,5-dioxo-1,2,4-triazolin-4-yl)benzoic acid (U4A) randomly attached to 1,4-polybutadiene form supramolecular aggregates which act as effective junction zones in new thermoplastic elastomers. Deuteron nuclear magnetic resonance (2H NMR) spectroscopy was used to investigate the molecular dynamics of the polymer backbone and the junction zones in selectively labelled samples. The spectra show motional heterogeneity along the polymer chain as well as in the supramolecular domains. Polybutadiene segments which are adjacent to these polar clusters are restricted in their mobility, even at temperatures 100 K above the …

Transparent thermoplastic polyurethanes based on aliphatic diisocyanates and polycarbonate diol

2016

Segmented thermoplastic polyurethanes (PUs) were synthetized using polycarbonate diol as soft segment with a molar mass of 500 and as a hard segment 1,5-pentanediol with a combination of isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI). Differential scanning calorimetry, differential mechanical analysis, Fourier transform infrared-attenuated total reflection spectroscopy, haze, transmittance, hardness, tensile properties and retention of tensile properties tests were employed to characterize the different PUs. The results of this study show that IPDI/HDI relation has a significant impact on the phase mixing, crystallinity and therefore on the PU’s properties. The variati…

Cooperative self-assembling in statistical copolymers: a new approach to high-temperature thermoplastic elastomers

1994

Based on previous work, where it was shown that 4-urazoylbenzoic acid (U4A) groups, which are attached statistically to polybutadiene, form ordered supramolecular arrays in the unpolar polymer matrix, the present work describes the synthesis of a new molecular building block capable of self-assembling in the unpolar polymer matrix. 5-Urazoylisophthalic acid (U35A) groups attached to 1,4-polybutadiene chains cause the formation of a thermoplastic elastomer of improved properties. The clusters of functional groups show an endothermic transition. The melting temperature increases for low levels of modification from 130°C up to 190°C. The mechanical properties (stress–strain and dynamic mechani…