抄録
D-lactic acid was synthesized from D-lactic acid methyl ester. Oligomeric (D-lactic acid) (ODLA) was prepared by dehydration condensation of D-lactic acid under high temperature and reduced pressure. Blend films of poly(L-lactic acid) (PLLA) and oligomeric (D-lactic acid) (ODLA) were obtained by cast method from their chloroform solutions. Properties of the blends were studied by polarizing microscopy, wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamic viscoelasticity measurement and tensile test. WAXD and DSC results showed that the stereocomplex crystal was formed in the blends and the melting temperature was higher than that of PLLA crystal. It was found from the results of DSC and dynamic viscoelasticity measurements that the formation of stereocomplex crystal disturbed the mobility of PLLA chain in the amorphous region of the blends. Furthermore, it was found that the mechanical properties of the PLLA film were hardly influenced by the addition of ODLA.
