Effect of Blending Asymmetry for Poly(L-lactic acid)/Poly(D-lactic acid) on Structural Change during Heating

摘要

Stereo-complex (Sc) crystallinity and corresponding melting characteristics of poly(L-lactic acid)/poly(D-lactic acid) blend films depend on blending asymmetry. Two different mechanisms for Sc-crystallization are observed in this study. The symmetrical blend of PLLA/PDLA=50/50 gives a combination of α-form melting and subsequent Sc-crystallization during heating. In contrast, the asymmetrical blend of 75/25 film exhibits solid transformation from α-form into Sc-form due to molecular slippage without melting.