Search results for "BIOPOLYMER"

VALORIZATION OF ANCHOVY FISHBONE WASTES FOR THE PREPARATION OF BIOPOLYMERIC BASED GREEN COMPOSITES FOR FOOD PACKAGING APPLICATIONS

Halloysite nanotubes-based nanocomposites for the hydrophobization of hydraulic mortar

2021

Abstract The treatment of stone surfaces for their protection from ageing caused by natural and anthropogenic effects is an open issue in materials development for Cultural Heritage. We thought interesting to verify the suitability of a modified cellulose biofilm filled with halloysite nanotubes as wax compatibilizers to design a protecting layer. A hydraulic mortar was selected as a stone prototype. To improve the physico-chemical properties of the covering layer, wax microparticles have been incorporated to control transport, consolidation and wettability features. In particular, different application protocols have been studied, namely brushing and spraying, to assess whether the propos…

Structure–Property Relationships in Bionanocomposites for Pipe Extrusion Applications

2021

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…

Mangiferin nanoemulsions in treatment of inflammatory disorders and skin regeneration

2018

Abstract In this paper mangiferin nanoemulsions were developed using hyaluronic acid of different molecular weight, in absence or presence of Transcutol-P. An extensive study was carried out on the physico-chemical properties of nanoemulsions. Nanosizer and transmission electron microscopy showed oil droplets average size 296 nm with monodisperses distribution (PI ≤ 0.30). The zeta potential was highly negative (−30 mV). FTIR analysis confirms the existence of physical interactions among compounds. Rheological measurements allowed to conclude that all formulations present a pseudoplastic behavior (s ∼ 0.4) in presence of the biopolymer. Moreover, mangiferin release depends on the molecular …

Etude de la stabilité de films industriels de PLA et de leur modification de surface pour des applications en tant qu'emballage alimentaire biodégrad…

2017

Poly(lactic acid) (PLA) is a biodegradable and renewable polyester, which is considered as the most promising eco-friendly substitute of conventional plastics. It is mainly used for food packaging applications, but some drawbacks still reduce its applications. On the one hand, its low barrier performance to gases (e.g. O2 and CO2) limits its use for applications requiring low gas transfer, such as modified atmosphere packaging (MAP) or for carbonate beverage packaging. On the other hand, its natural water sensitivity, which contributes to its biodegradation, limits its use for high moisture foods with long shelf life.Other biopolymers such as wheat gluten (WG) can be considered as interesti…

Antimicrobial and antioxidant supramolecular ionic liquid gels from biopolymer mixtures

2023

In this work, we describe the preparation and characterization of supramolecular ionic liquid gels based on binary mixtures of biopolymers, comprising chitosan, chitin, cellulose and lignin. The gels were obtained in ionic liquids differing in the cation or the anion, with no need for a cross-linking agent or acid treatment. The materials obtained were characterized for the minimum gelation concentration, porosity, swelling and rheological properties, finding a prominent influence of the nature of the ionic liquid anion. Then, we investigated the ability of the gels to scavenge free radicals, finding that the gels exhibit a higher antioxidant ability than their individual components. Moreov…

Green Composites Based on Hedysarum coronarium with Outstanding FDM Printability and Mechanical Performance

2022

The addition of natural scraps to biodegradable polymers has gained particular interest in recent years, allowing reducing environmental pollution related to traditional plastic. In this work, new composites were fabricated by adding 10% or 20% of Hedysarum coronarium (HC) flour to Poly (lactic acid) (PLA). The two formulations were first produced by twin screw extrusion and the obtained filaments were then employed for the fabrication of composites, either for compression molding (CM) or by fused deposition modeling (FDM), and characterized from a morphological and mechanical point of view. Through FDM it was possible to achieve dense structures with good wettability of the filler that, on…

Hedysarum coronarium-Based Green Composites Prepared by Compression Molding and Fused Deposition Modeling

2022

In this work, an innovative green composite was produced by adding Hedysarum coronarium (HC) flour to a starch-based biodegradable polymer (Mater-Bi®, MB). The flour was obtained by grinding together stems, leaves and flowers and subsequently sieving it, selecting a fraction from 75 μm to 300 μm. Four formulations have been produced by compression molding (CM) and fused deposition modeling (FDM) by adding 5%, 10%, 15% and 20% of HC to MB. The influence of filler content on the processability was tested, and rheological, morphological and mechanical properties of composites were also assessed. Through CM, it was possible to obtain easily homogeneous samples with all filler amounts.…

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

2010

BIOPOLYMERS USED AS EDIBLE COATING TO LIMIT WATER TRANSFER, COLOUR DEGRADATION AND AROMA COMPOUND 2-PENTANONE LOST IN MEXICAN FRUITS

2005

Low preservation of typical fruits in countries with warm weather represents a limitation to export. A recently proposed method to increase shelf-life of fresh guava, is the application of biopolymers as edible coatings. This research involves the use of biopolymers of microbial origin obtained with low cost nutrients, to prepare edible coatings applied on mexican guava and apricot. Dextrans obtained by fermentation with Leuconostoc mesenteroides isolated from a typical mexican beverage named pulque (cactus juice fermented). Dextrans were purified by precipitation with methanol and dispersed in purified water. This procedure was repeated 3 times to eliminate carbohydrates others than dextra…