Preparation of Nano-Particles of Stereo-Complex Crystals of Poly(lactic acid)

Abstract

Stereo-complex crystallization of poly(l-lactic acid) (PLLA) and poly(d-lactic acid) (PDLA) was performed by flowing their blend solution through nano-channels of porous membranes. The spacing restriction within the nano-channels induces the contact between PLLA and PDLA chains. The stereo-complex crystalline structure of the obtained material was confirmed by differential scanning calorimetry and X-ray measure­ments. Morphological observation by scanning electron microscope indicates that the characteristic nano-particles with the diameter corresponding to channel width aggregate each other. Such nano-particles play a role of nucleating agent for matrix crystallization when they are blended with pure PLLA.