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Biodegradable films based on sodium alginate and aloe vera were prepared by casting technique. The resulting films were characterized by swelling behavior, scanning electron microscopy, biodegradation, as well as mechanical and barrier properties. The aloe vera gel exerted a positive influence on mechanical and physico-chemical properties. Aloe vera gel improved the tensile strength of the films giving maximum value of 21.20 N/[mm.sup.2] at 20% gel. Water vapor permeability of the composite films was reduced which made the film more effective as a moisture barrier, giving the most efficient result of 1.16 * [10.sup.-10] g [m.sup.-1] [s.sup.-1] [Pa.sup.-]1 at 50% aloe vera gel. The present study demonstrates the viability of the composite alginate aloe vera films as a biodegradable alternative to synthetic plastic films for the packaging of food materials. KEYWORDS aloe vera gel, biodegradable film, glycerol, sodium alginate, 1 | INTRODUCTION The purpose of food packaging films is to retain the quality and safety of food products during transportation and storage until consumption. [1,2] The films protect food [...]

Owing to its biosynthetic and biodegradable properties, polylactic acid (PLA) is considered to be a most promising biopolymer that could play a crucial role as a potentially environmentally friendly material for a sustainable bioeconomy. However, its long-life cycle indicates that it cannot be easily degraded in nature. Therefore, understanding the biodegradation mechanism of PLA is important for reducing the impacts of waste plastic and waste disposal. With the recent development of molecular biology techniques, some studies have confirmed that specific groups of microorganisms can facilitate the biodegradation of PLA. Here, recent advances in the biodegradation of PLA (i.e., microbial and enzymatic degradation) and key factors affecting the degradation efficiency were reviewed. In addition, compared with complete degradation through mineralization, upcycling is also proposed as a more recyclable strategy for disposing of waste plastics. Key words: PLA, biodegradation, microorganisms, enzymes, upcycling. En raison de son caractere biosynthetique et biodegradable, l'acide polylactique (PLA) est considere comme le biopolymere le plus prometteur parmi toutes les matieres plastiques, qui jouera un role cle en tant que materiau potentiellement ecologique dans une bioeconomie durable. Toutefois, son long cycle de vie indique qu'il ne peut pas etre facilement degrade dans la nature. Il est donc important de comprendre le mecanisme de biodegradation du PLA pour reduire les impacts des dechets plastiques. Avec le developpement recent des techniques de biologie moleculaire, certaines etudes ont confirme que des groupes specifiques de micro-organismes peuvent favoriser le processus de biodegradation du PLA. Dans cet article de synthese, les progres recents dans la biodegradation du PLA (c'est-a-dire la degradation microbienne et enzymatique) et les facteurs cles affectant l'efficacite de la degradation ont ete examines. En outre, par rapport a la degradation complete par mineralisation, le recyclage valorisant est aussi propose comme meilleure strategie de recyclage pour eliminer les dechets plastiques. [Traduit par la Redaction] Mots-cles : PLA, biodegradation, micro-organismes, enzymes, recyclage valorisant., Introduction Owing to the increased global population and considerable resource consumption, significant increases in environmental pollution and waste accumulation have occurred. Plastics have ushered in a new era for daily [...]

Polyglycolic acid (PGA) is a class of semicrystalline, bioresorbable polymers that have been widely used in a number of applications. No other bioresorbable materials can fully replace PGA in tissue engineering. Understanding degradation mechanisms in PGA is important for improving the efficiency and effectiveness in various fields including implantation. This review begins with a discussion on terminology of polymer degradation and hydrolytic degradation mechanism with a delineative model. This review also focus on previous degradation studies taking advantage of its fast-degrading behavior and the mechanism behind hexafluoroisopropanol (HFIP) being the sole solvent for PGA. Finally, the merits of PGA are discussed with many potential future applications along with their associated challenges. KEYWORDS bioresorbable polymer, degradation mechanism, hydrolytic degradation, polyglycolic acid, solubility in HFIP, tissue engineering, 1 | INTRODUCTION In this era of advancement of technology and research, engineers and scientists have been looking for a way to push the development of technology and people's health [...]

Present study explored the swelling behavior, biodegradability and flocculation efficiency of hydrogel polymer based on renewable backbones-psyllium and gum rosin. Swelling studies revealed that the polymer sample exhibit pH and temperature-dependent swelling behavior. The polymer sample was assessed for its flocculation efficiency by optimizing the process parameters such as polymer dose, pH, and temperature. The polymer sample illustrated the maximum flocculation efficiency of 96% in 500 mg/L kaolin suspension under optimized experimental conditions. Investigation of biodegradation behavior was carried out using the soil burial and composting method. The percentage degradation of the polymer sample was observed to be 86.8% and 90.4% in 63 days using soil burial and composting method, respectively. The progress of biodegradation was analyzed through Fourier transform infrared and scanning electron microscopy techniques. Thus, the polymer sample was found to be cost effective, eco-friendly, biodegradable material that has significant flocculation characteristics, and hence can be utilized for treatment of kaolinated wastewater. KEYWORDS biodegradation, flocculation, gum rosin, psyllium, swelling, 1 | INTRODUCTION Hydrogels are the three-dimensional polymeric structures that can absorb large amount of water without itself getting dissolved. The ability of hydrogels to absorb water is due to [...]

Traditional plasticizers to modify polylactic acid (PLA) usually leads to limited biodegradation, due to its inherent non-biodegradability of additives. In this work, we report a melt blending method to modify PLA using the alginic acid and two different alginates combined with nano CaC[O.sub.3], a fully sustainable and biodegradable component. And, the mechanical, thermal, and rheological properties of the composites are investigated. We demonstrated that the filled samples show a lower tensile strength and higher impact strength which means a toughening effect occurs. Dynamic mechanical analysis experiments showed that the calcium alginate-f illed samples show higher performances than other filled samples not only in static mechanical but also dynamic mechanical properties. The fracture morphology of the samples shows that a better interfacial reaction has been constituted for gel calcium alginate between CaC[O.sub.3] and PLA. Nevertheless, the thermogravimetric analysis results indicate that a lower thermal stability has been achieved in alginate filled samples. Chemorheological study indicated the alginate-filled samples also show a lower modulus and viscosity than neat PLA. It was found that the complex viscosity decrease with the addition of alginates, in comparison with PLA/CaC[O.sub.3] composites, and the samples filled with calcium alginate show a higher viscosity than those of sodium alginate and alginic acid. The alginate derivatives showed interesting potential as new green plastic additives attributed to origin from the biodegradable natural resources with a polymeric matrix., INTRODUCTION Sustainability has become more and more important in recent years, especially in the case of the increased environmental concerns and resources over consumption with respect to the fossil-based polymers. [...]

To increase the degradation rate of poly(lactic acid) (PLA), soy protein concentrate (SPC) was introduced via melt compounding using a self-developed, co-rotating, non-twin-screw extruder. Poly(2-ethyl-2-oxazoline) (PEOX) and diphenyl methane diisocyanate (MDI) were added to plasticize the melt and improve the compatibility between PLA and SPC. The PLA/SPC blends were subsequently foamed using supercritical carbon dioxide (C[O.sub.2]) as a blowing agent to produce porous composites. The involvement of SPC promoted cold crystallization of PLA but reduced the thermal stability of the blends. PLA showed a strong interfacial bonding with modified SPC, and the SPC formed continuous three-dimensional networks when its proportion reached 30 wt%. In the foaming process, SPC domains acted as heterogeneous nucleation sites, which resulted in enhanced cell densities and reduced cell diameters. The PLA/SPC (70:30) sample showed the finest cell structure due to the presence of the SPC network. For the same blends, increasing the foaming pressure from 16 to 20 MPa enhanced the cell density by about 5 times. The water absorption rate and the biodegradation rate of the PLA/SPC foams were much higher than that of neat PLA due to the hydrophilicity of SPC and the porous structure of the foams., INTRODUCTION In the recent years, biobased polymers have received great interest as renewable plastics because of their biodegradability and biocompatibility [1-4]. PLA, which is a compostable polymer derived from renewable [...]