Properties of Plasticized Polylactic Acid Films with Epoxidized Rubber Seed Oil

Abstract

Epoxidized rubber seed oil (ERSO) was synthesized through the epoxidation reaction and used as a plasticizer for polylactic acid (PLA) films. In this study, PLA films were plasticized with different contents of ERSO (5, 7, 10, 15 and 20% by weight) in order to enhance their flexibility. The plasticized films were formed by solvent casting. To determine the effects of the plasticizer, properties such as thermal stability, surface morphology, mechanical strength and flexibility of the films were investigated. Results show that a higher ERSO content leads to an increase in thermal stability and elongation at break, while it lowers tensile strength and glass transition temperature (Tg). At 15% ERSO, an elongation at break 18 times higher than that of a PLA film without any ERSO plasticizer was achieved. Moreover, at 15% ERSO and less, SEM micrographs exhibit uniform dispersion of ERSO phase in PLA matrix, which indicates their compatibility. Overall, the results show the potential of ERSO as a bio-plasticizer for PLA.