Polyblends and composites of poly (lactic acid) (PLA): a review on the state of the art

Abstract

Polymers obtained from renewable sources are gaining popularity over their petroleum based counter parts in recent years due to their capability to address the environmental pollution related concerns emanating from the widespread usage of synthetic polymers. Even though the polymers from renewable sources are attractive in an environmental point of view, some of the property limitations and the high cost of these materials pose limitations for their extensive commercial applications. These aspects opened the door for a large chunk of research activities in development of polyblends and composites containing polymers from renewable sources as one of the components. Poly (lactic acid) (PLA) is one of the most discussed and commercialized polymer originated from renewable resources. Even though it has many useful properties, certain disadvantages like high brittleness, low impact resistance etc. limit the wide spread commercialization of PLA. In this review article, the recent research activities which are aimed to fill this gap by various modifications of PLA are discussed with special emphasis on the latest research advancements in the field of biodegradable and non biodegradable systems containing PLA.

Super Tough Polylactic Acid Plasticized with Epoxidized Soybean Oil Methyl Ester for Flexible Food Packaging

“…PLA can be synthesized either by the simple polycondensation of lactic acid or the ring opening polymerization of the cyclic diester of lactic acidlactide. , Although obtaining a high molecular weight polymer can be challenging via the former route, an azeotropic dehydration process can be employed to remove water and drive the equilibrium of the reaction toward the product. , However, NatureWorks, a world-leading biopolymer supplier, utilizes ring opening melt polymerization of lactide with a tin catalyst, which in general is more commonly employed in industry …”

Blown film stability for low, medium, and high molecular weight polylactic acid and their tensile properties

“…5 Research on PLA has substantially increased, covering almost every branch of science including medicine, biochemistry, physics, engineering, and materials science. 5,6 PLA is a biobased, biodegradable, semi-crystalline, linear, aliphatic polyester. 3,5,6 Its initial uses were limited to medical applications owing to high cost and low availability, but it has since extended to general parts processed by injection molding, blow molding, sheet and film extrusion, foaming, fiber spinning, thermoforming and 3D printing.…”

“…1,10,11 Despite having a low heat deflection temperature (58°C) and relative brittleness, 3,11 its GRAS status, low temperature heat seal, low coefficient of friction and resistance to oils, make it appropriate for packaging applications. 5,6…”

“…3,5,6 Its initial uses were limited to medical applications owing to high cost and low availability, but it has since extended to general parts processed by injection molding, blow molding, sheet and film extrusion, foaming, fiber spinning, thermoforming and 3D printing. 5,6 PLA production is a multistep process. The monomer (lactic acid) is obtained via bacterial fermentation using carbohydrates from sugarcane or corn as carbon source.…”

Isolation, identification, and application of lactic acid-producing bacteria using salted cheese whey substrate and immobilized cells technology

“…Lactic acid (LA) is widely used for various applications in food and non-food industries. It has served as a raw material in the production of valuable products [1]. The commercial production level of LA can be achieved using either chemical synthesis or microbial fermentation.…”