Epoxy functionalized poly(lactide) reactive modifier for blown film applications

Abstract

Epoxy functionalized poly(lactide) (EF-PLA) was synthesized by reacting PLA with a multifunctional epoxy polymer (MEP) using reactive extrusion processing. These polymers can function as a rheology modifier for PLA and a compatibilizer for other biopolyesters in blown film and foam applications. Model compound studies show that the epoxy functional group on the MEP reacts selectively with the carboxylic acid chain-ends of PLA at processing temperatures below 200 C. An EF-PLA containing up to 10% MEP was prepared without gel formation and reactively extruded with neat PLA to obtain three different product formulations containing MEP (0.25, 0.5, and 1.0%). These products showed significantly enhanced rheological properties compared to what has been reported by other groups and is currently used in the PLA blown film industry, the blending of MEP with PLA in a single step. These benefits are a result of how the MEP gets distributed in the material, and can lead to improved properties even at lower MEP concentrations. Our new materials showed significant strain hardening rheological behavior demonstrating that they can be readily blown into films and foams. A statistical simulation was developed to provide a fundamental understanding of the reaction as well as provide information on the molecular weight characteristics and reactivity of the EF-PLA. The EF-PLA molecule shows good potential for use as a rheology modifier and compatibilizer. V C 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42243.

Biodegradable compatibilized polymer blends for packaging applications: A literature review

“…Multifunctional epoxy functionalized PLA (ME‐PLA) has been used to compatibilize the PLA/PBAT blend for blown film applications . In the presence of ME‐PLA compatibilizer, the blown films can be produced with up to 70% PLA incorporation in the PLA/PBAT blends, whereas the PLA/PBAT blend allowed maximum of 40% PLA to produce blown film without compatibilizer because of the poor compatibility and rheological properties.…”

“…In the presence of ME‐PLA compatibilizer, the blown films can be produced with up to 70% PLA incorporation in the PLA/PBAT blends, whereas the PLA/PBAT blend allowed maximum of 40% PLA to produce blown film without compatibilizer because of the poor compatibility and rheological properties. The ME‐PLA compatibilizer leads to the formation of copolymer ME‐PLA‐ g ‐PBAT (Figure ) at the interface which is then used to compatibilize the PLA and PBAT phase . The reactive PLA/PBAT blend showed higher tensile properties than the PLA/PBAT blend prepared without compatibilizer.…”

“… Reactive compatibilization of PLA/PBAT blends with epoxy functionalized‐PLA compatibilizer (Redrawn from Ref. ). [Color figure can be viewed at http://wileyonlinelibrary.com]…”

DGEBA‐Based Epoxy Resin as Compatibilizer for Biodegradable Poly (lactic acid)/Poly(butylene adipate‐co‐terephthalate) Blends

“…The last one are multifunctional additives which contain functional groups able to react with the hydroxyl and carboxyl groups at the end of both polymer chains should provide a good anchorage between them, thus extending the chain an improving the interfacial adhesion . In this sense, multifunctional random copolymers containing epoxide groups have been extensively used, as epoxide groups can readily react with COOH groups located at the end of both PLA and PBAT chains . Zhang et al used a random terpolymer of ethylene, acrylic and glycidyl methacrylate as reactive interfacial agent for PLA/PBAT blends and obtained good compatibilization and higher hardness without affect the tensile strength.…”

Influence of Biodegradable Poly(butylene carbonate) on Plasticized Polylactide Blown Films

“…Rangari and Vasanthan 29 studied strain-induced crystallization and enzymatic degradation of drawn poly(L-lactic acid) films. Schneider et al 32 synthesized epoxy -functionalized PLA by reacting PLA with a multifunctional epoxy polymer using reactive extrusion processing. Tabasi et al 30 investigatied the seal behavior of poly(lactic acid)/PCL cast films.…”