Cooperative effects of nucleation agent and plasticizer on crystallization properties of stereocomplex‐type poly(lactide acid)

Abstract

An investigation of the cooperative effects of plasticizer (PEG) and nucleation agent (TMC‐306) on stereocomplex‐type poly(lactide acid) formation and crystallization behaviors between poly(L‐lactide acid) (PLLA) and poly(D‐lactide acid) (PDLA) was conducted. Wide‐angle X‐ray diffraction (WAXD) and differential scanning calorimetry (DSC) analysis indicated that exclusive stereocomplex‐type poly(lactide acid) (sc‐PLA) crystallites without any homocrystallites poly(lactide acid) (hc‐PLA) did form by incorporation of PEG, TMC‐306, or both at a processing temperature higher than the melting temperature of sc‐PLA (around 230°C). The non‐isothermal and isothermal crystallization kinetics showed that PEG and TMC‐306 could independently accelerate the crystallization rate of sc‐PLA. The crystallization peak temperature and crystallization rate of sc‐PLA were significantly improved by the presence of PEG and TMC‐306. The influence of PEG and TMC‐306 on the morphologies of sc‐PLA was also investigated using polarized optical microscopy (POM). Copyright © 2016 John Wiley & Sons, Ltd.