Properties of poly(lactic acid) plasticized by epoxidized rubber seed oil

Abstract

In this study, epoxidized rubber seed oil (EeRSO) was utilized as a plasticizer for polylactic acid (PLA) using a melt blending method at five weight ratios of PLA/EeRSO, 100/0, 97.5/2.5, 95/5, 92.5/7.5, and 90/10, respectively. The plasticization of PLA with EeRSO lowered the Tg as well as cold-crystallization temperature. The tensile properties demonstrated that the addition of EeRSO to PLA led to a strong increase in elongation at break and tensile toughness, but a decrease in tensile strength. The impact strength of PLA was improved by 103 %, with the presence of 7.5 wt.% EeRSO. The SEM image of the plasticized PLA showed good compatible morphology without voids. The initial decomposition temperature grew from 261.8 to 308.83 °C and the weight loss at 384 °C of PLA reduced from 91.2 to 81.5 % with the presence of 5 wt.% EeRSO. Based on the results of this study, EeRSO may be used as an environmentally friendly plasticizer that can improve the overall properties of PLA.