Study of Cell Nucleation in Microcellular Poly(lactic acid) Foamed with Supercritical CO2through a Continuous-Extrusion Process

2010 ◽  
Vol 49 (5) ◽  
pp. 2186-2193 ◽  
Author(s):  
Laurent M. Matuana ◽  
Carlos A. Diaz
Keyword(s):  
Lactic Acid ◽  
Extrusion Process ◽  
Poly Lactic Acid ◽  
Cell Nucleation ◽  
Continuous Extrusion

scholarly journals Hybrid Biocomposites Based on Poly(Lactic Acid) and Silica Aerogel for Food Packaging Applications

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4910 ◽  
Author(s):  
Alejandro Aragón-Gutierrez ◽  
Marina P. Arrieta ◽  
Mar López-González ◽  
Marta Fernández-García ◽  
Daniel López
Keyword(s):  
Thermal Stability ◽  
Lactic Acid ◽  
Silica Aerogel ◽  
Food Packaging ◽  
Mechanical Performance ◽  
Composite Films ◽  
Barrier Properties ◽  
Extrusion Process ◽  
Poly Lactic Acid ◽  
Barrier Performance

Bionanocomposites based on poly (lactic acid) (PLA) and silica aerogel (SiA) were developed by means of melt extrusion process. PLA-SiA composite films were plasticized with 15 wt.% of acetyl (tributyl citrate) (ATBC) to facilitate the PLA processability as well as to attain flexible polymeric formulations for films for food packaging purposes. Meanwhile, SiA was added in four different proportions (0.5, 1, 3 and 5 wt.%) to evaluate the ability of SiA to improve the thermal, mechanical, and barrier performance of the bionanocomposites. The mechanical performance, thermal stability as well as the barrier properties against different gases (carbon dioxide, nitrogen, and oxygen) of the bionanocomposites were evaluated. It was observed that the addition of 3 wt.% of SiA to the plasticized PLA-ATBC matrix showed simultaneously an improvement on the thermal stability as well as the mechanical and barrier performance of films. Finally, PLA-SiA film formulations were disintegrated in compost at the lab-scale level. The combination of ATBC and SiA sped up the disintegration of PLA matrix. Thus, the bionanocomposites produced here show great potential as sustainable polymeric formulations with interest in the food packaging sector.

Effect of Compatibilizers on Composite Materials of Bio-Ethanol Byproduct-Poly(lacticacid)

2012 ◽  
Vol 204-208 ◽  
pp. 4088-4092
Author(s):  
Ming Ming Zhang ◽  
Xiao Huan Liu ◽  
Chun Peng Wang ◽  
Li Wei Jin
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Composite Materials ◽  
Extrusion Process ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Process Effects ◽  
Properties Of Composites

The blend composite materials of bio-ethanol byproduct-Poly(lactic acid) (PLA) were produced by a twin-screw extrusion process. Effects of bio-ethanol byproduct (BEB) contents and different compatibilizers on properties of composite materials were investigated. The research showed that with the increase of contents of bio-ethanol byproduct, the mechanical properties decreased. The mechanical properties of composites were improved by adding the compatibilizers, especially the polypropylene grafted maleic anhydride (PP-MAH). When the PP-MAH content was 2.5%, the mechanical properties of the composite materials were superior to others.

scholarly journals Effect of chitosan addition in starch and poly(lactic acid) sheets produced by extrusion

2015 ◽  
Vol 6 (1) ◽  
pp. 80
Author(s):  
Matheus Luz Alberti ◽  
Sílvio José De Souza ◽  
Heliberto Gonçalves ◽  
Fabio Yamashita ◽  
Marianne Ayumi Shirai
Keyword(s):  
Lactic Acid ◽  
Water Vapor ◽  
Food Packaging ◽  
Water Vapor Permeability ◽  
Barrier Properties ◽  
Extrusion Process ◽  
Pilot Scale ◽  
Poly Lactic Acid ◽  
Vapor Permeability ◽  
Water Vapor Barrier

<p>The use of blends containing biodegradable polymers like starch and poly (lactic acid) (PLA) has gained considerable attention, especially for the food packaging production. Current research has also highlighted the use of chitosan because their antimicrobial activity, biodegradability and applicability in the production of active biodegradable food packaging. The objective of this work was to produce cassava starch and PLA sheets incorporated with chitosan by flat extrusion process (calendering-extrusion), and evaluate the mechanical, water vapor barrier and microstructural properties. In order to simplify the obtainment of the material reducing processing steps, all components of the blend were homogenized in one step extrusion The incorporation of chitosan in the starch/PLA sheets decreased significantly the tensile strength, Young's modulus, elongation at break and density. In addition, the scanning electron microscopy images showed the formation of non-homogeneous mixtures with the presence of pores between the blend compounds, and this fact affected the water vapor barrier properties increasing water vapor permeability, solubility and diffusion coefficients. It was possible to conclude that although the incorporation of chitosan to the starch/PLA sheets has not contributed to obtain materials with suitable properties, it was able to produce them by calendering-extrusion process in pilot scale. Studies about chitosan incorporation in starch and PLA sheets still needed.</p><p>&nbsp;</p><p>DOI: 10.14685/rebrapa.v6i1.208</p><p>&nbsp;</p>

scholarly journals Poly(Lactic Acid)-Based Nanobiocomposites with Modulated Degradation Rates

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1943 ◽  
Author(s):  
Iozzino Valentina ◽  
Askanian Haroutioun ◽  
Leroux Fabrice ◽  
Verney Vincent ◽  
Pantani Roberto
Keyword(s):  
Lactic Acid ◽  
Succinic Acid ◽  
Extrusion Process ◽  
Poly Lactic Acid ◽  
Melt Compounding ◽  
Degradation Rates ◽  
Rate Of Hydrolysis ◽  
Plastic Industry ◽  
Double Hydroxides ◽  
Kinetics Of

In the field of biodegradable polymers such as poly(Lactic Acid) (PLA), it is quite well known that their kinetics of hydrolysis strongly depend on the pH of the hydrolyzing medium. The idea explored during this study focused on PLA, is the addition of additives that are able to control the pH of water when it diffuses inside the polymer. For instance, acids (i.e. succinic acid, also used as food additive) are bio- and eco- friendly additives that are able to play this role. In order to control the release of these molecules and their dispersion inside the polymer, their intercalation in biocompatible nanofillers like layered double hydroxides (LDH) is here considered. The additives have been dispersed in the polymer by melt compounding, commonly used in the plastic industry. Several composites of PLA (4032D) and LDH intercalated with organic acids (succinic, fumaric, and ascorbic acid) have been obtained by an extrusion process. From all extruded materials, PLA films obtained by compression molding were then subjected to hydrolysis tests. The results showed that the mentioned molecules, dispersed in the polymer, are able to control the rate of hydrolysis, and experimental results show an increase of degradation time for samples containing LDH-organic acid (in particular with LDH-succinic acid), making such hybrid additives an appropriate and efficient solution for PLA.

scholarly journals Functional Nanocomposite Films of Poly(Lactic Acid) with Well-Dispersed Chitin Nanocrystals Achieved Using a Dispersing Agent and Liquid-Assisted Extrusion Process

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4557
Author(s):  
Mitul Patel ◽  
Daniel Schwendemann ◽  
Giorgia Spigno ◽  
Shiyu Geng ◽  
Linn Berglund ◽  
...  
Keyword(s):  
Lactic Acid ◽  
High Performance ◽  
Functional Materials ◽  
Microscopy Study ◽  
Extrusion Process ◽  
Nanocomposite Films ◽  
Poly Lactic Acid ◽  
Dispersing Agent ◽  
Triethyl Citrate ◽  
Performance Functional

The development of bio-based nanocomposites is of high scientific and industrial interest, since they offer excellent advantages in creating functional materials. However, dispersion and distribution of the nanomaterials inside the polymer matrix is a key challenge to achieve high-performance functional nanocomposites. In this context, for better dispersion, biobased triethyl citrate (TEC) as a dispersing agent in a liquid-assisted extrusion process was used to prepare the nanocomposites of poly (lactic acid) (PLA) and chitin nanocrystals (ChNCs). The aim was to identify the effect of the TEC content on the dispersion of ChNCs in the PLA matrix and the manufacturing of a functional nanocomposite. The nanocomposite film’s optical properties; microstructure; migration of the additive and nanocomposites’ thermal, mechanical and rheological properties, all influenced by the ChNC dispersion, were studied. The microscopy study confirmed that the dispersion of the ChNCs was improved with the increasing TEC content, and the best dispersion was found in the nanocomposite prepared with 15 wt% TEC. Additionally, the nanocomposite with the highest TEC content (15 wt%) resembled the mechanical properties of commonly used polymers like polyethylene and polypropylene. The addition of ChNCs in PLA-TEC15 enhanced the melt viscosity, as well as melt strength, of the polymer and demonstrated antibacterial activity.

Thermoplastic starch/polyester films: Effects of extrusion process and poly (lactic acid) addition

2013 ◽  
Vol 33 (7) ◽  
pp. 4112-4117 ◽  
Author(s):  
Marianne Ayumi Shirai ◽  
Juliana Bonametti Olivato ◽  
Patrícia Salomão Garcia ◽  
Carmen Maria Olivera Müller ◽  
Maria Victória Eiras Grossmann ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Thermoplastic Starch ◽  
Extrusion Process ◽  
Poly Lactic Acid ◽  
Acid Addition

scholarly journals Role of Hybrid Nano-Zinc Oxide and Cellulose Nanocrystals on the Mechanical, Thermal, and Flammability Properties of Poly (Lactic Acid) Polymer

2021 ◽  
Vol 5 (2) ◽  
pp. 43
Author(s):  
Dilpreet S. Bajwa ◽  
Jamileh Shojaeiarani ◽  
Joshua D. Liaw ◽  
Sreekala G. Bajwa
Keyword(s):  
Zinc Oxide ◽  
Lactic Acid ◽  
Zno Nanoparticles ◽  
Cellulose Nanocrystals ◽  
Thermal Characteristics ◽  
Extrusion Process ◽  
Shielding Effect ◽  
Poly Lactic Acid ◽  
Flame Resistance ◽  
Nano Zinc Oxide

Biopolymers with universal accessibility and inherent biodegradability can offer an appealing sustainable platform to supersede petroleum-based polymers. In this research, a hybrid system derived from cellulose nanocrystals (CNCs) and zinc oxide (ZnO) nanoparticles was added into poly (lactic acid) (PLA) to improve its mechanical, thermal, and flame resistance properties. The ZnO-overlaid CNCs were prepared via the solvent casting method and added to PLA through the melt-blending extrusion process. The composite properties were evaluated using SEM, a dynamic mechanical analyzer (DMA), FTIR TGA, and horizontal burning tests. The results demonstrated that the incorporation of 1.5% nano-CNC-overlaid ZnO nanoparticles into PLA enhanced the mechanical and thermal characteristics and the flame resistance of the PLA matrix. Oxidative combustion of CNC-ZnO promoted char formation and flame reduction. The shielding effect from the ZnO-CNC blend served as an insulator and resulted in noncontinuous burning, which increased the fire retardancy of nanocomposites. By contrast, the addition of ZnO into PLA accelerated the polymer degradation at higher temperature and shifted the maximum degradation to lower temperature in comparison with pure PLA. For PLA composites reinforced by ZnO, the storage modulus decreased with ZnO content possibly due to the scissoring effect of ZnO in the PLA matrix, which resulted in lower molecular weight.

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