Poly (lactic acid)/modified gum arabic based bionanocomposite films: Thermal degradation kinetics

Strong, bacteriostatic and transparent polylactic acid-based composites by incorporating quaternary ammonium cellulose nanocrystals

Renewable natural fibers (e.g., cellulose nanocrystals (CNCs)) are being applied for reinforcing bio-based polylactic acid (PLA). For improvement in the interfacial compatibility between CNCs and PLA and the dispersibility of CNCs, a quaternary ammonium salt-coated CNCs (Q-CNCs) hybrid was prepared in this study based on an esterification self-polymerization method, and such hybrid was further utilized as a new strengthening/toughening nanofiller for producing the Q-CNCs-reinforced PLA composite. The results confirmed that quaternary ammonium salt coatings could efficiently enhance CNCs/PLA interfacial compatibility via mechanical interlocking and semi-interpenetrating networks. Attributing to the synergistic effect of quaternary ammonium salts and CNCs, a considerable enhancement in processing, mechanical, and thermal properties was gained in the obtained Q-CNCs-reinforced PLA composite. With the addition of 0.5 wt% Q-CNCs, the tensile strength, Young's modulus, and elongation at break of the Q-CNCs-reinforced PLA composite was raised by approximately 23 %, 37 % and 18 %, respectively; compared with pure PLA, the obtained composite had excellent bacteriostatic properties and good transparency. This work discusses the development of high-performance, low-cost and sustainable PLA-based composites on a potential application in packaging materials.

A review on bio-based polymer polylactic acid potential on sustainable food packaging

Poly(lactic acid) (PLA) stands as a compelling alternative to conventional plastic-based packaging, signifying a notable shift toward sustainable material utilization. This comprehensive analysis illuminates the manifold applications of PLA composites within the realm of the food industry, emphasizing its pivotal role in food packaging and preservation. Noteworthy attributes of PLA composites with phenolic active compounds (phenolic acid and aldehyde, terpenes, carotenoid, and so on) include robust antimicrobial and antioxidant properties, significantly enhancing its capability to bolster adherence to stringent food safety standards. The incorporation of microbial and synthetic biopolymers, polysaccharides, oligosaccharides, oils, proteins and peptides to PLA in packaging solutions arises from its inherent non-toxicity and outstanding mechanical as well as thermal resilience. Functioning as a proficient film producer, PLA constructs an ideal preservation environment by merging optical and permeability traits. Esteemed as a pioneer in environmentally mindful packaging, PLA diminishes ecological footprints owing to its innate biodegradability. Primarily, the adoption of PLA extends the shelf life of products and encourages an eco-centric approach, marking a significant stride toward the food industry's embrace of sustainable packaging methodologies.

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A Review: Research Progress in Modification of Poly (Lactic Acid) by Lignin and Cellulose

With the depletion of petroleum energy, the possibility of prices of petroleum-based materials increasing, and increased environmental awareness, biodegradable materials as a kind of green alternative have attracted more and more research attention. In this context, poly (lactic acid) has shown a unique combination of properties such as nontoxicity, biodegradability, biocompatibility, and good workability. However, examples of its known drawbacks include poor tensile strength, low elongation at break, poor thermal properties, and low crystallization rate. Lignocellulosic materials such as lignin and cellulose have excellent biodegradability and mechanical properties. Compounding such biomass components with poly (lactic acid) is expected to prepare green composite materials with improved properties of poly (lactic acid). This paper is aimed at summarizing the research progress of modification of poly (lactic acid) with lignin and cellulose made in in recent years, with emphasis on effects of lignin and cellulose on mechanical properties, thermal stability and crystallinity on poly (lactic acid) composite materials. Development of poly (lactic acid) composite materials in this respect is forecasted.