The effects of Ethoxylated Bisphenol A Dimethacrylates content on the thermal and thermo-mechanical properties of chemical crosslinked Polylactic acid

Abstract

Crosslinking structures of PLA can be effectively introduced into PLA by melt mixing using the initiation of dicumyl peroxide (DCP) in the presence of ethoxylated bisphenol A dimethacrylates (Bis−EMAs) which was used as a crosslinking agent. The results showed that the introduction of DCP into PLA above 3 phr increased storage modulus and complex viscosity when compared to PLA. DCP/PLA in the presence of Bis−EMAs content showed the optimum of storage modulus and complex viscosity were at a 5 phr Bis–EMAs loading and decreased as more Bis–EMAs were incorporated into DCP/PLA. The thermal stability of DCP/PLA/Bis–EMAs did not change when compared to PLA. Moreover, glass transition and cold crystallization temperatures of 0.3DCP/PLA/Bis–EMAs and 0.5DCP/PLA/Bis–EMAs slightly increased with increasing Bis–EMAs content. The crystallinity of DCP/PLA and DCP/PLA/Bis–EMAs were lower than that of PLA. The introductions of DCP and Bis–EMAs into PLA showed an increase of Young’s modulus and a decrease of elongation at break. In addition, the dynamic mechanical properties revealed the improvement in high-temperature performance efficiency of the crosslinked PLAs where, in this work, their flow, thermal, mechanical and dynamic mechanical properties increased with increasing Bis−EMAs content up to 5 phr.