Premium
Synthesis and Thermomechanical Properties of Stereo Triblock Polylactides With Nonequivalent Block Compositions
Author(s) -
Masutani Kazunari,
Lee Chan Woo,
Kimura Yoshiharu
Publication year - 2012
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.201100683
Subject(s) - crystallinity , polymer chemistry , crystallization , materials science , enantiomer , block (permutation group theory) , lactide , copolymer , chemistry , composite material , stereochemistry , polymer , organic chemistry , mathematics , geometry
ABA stereo triblock polylactides consisting of PLLA and PDLA are prepared by two‐step ROP of L ‐ and D ‐lactides. In the first step, PDLA prepolymers with bishydroxyl terminals are prepared that are then used as macroinitiators in the ROP of L ‐lactide to obtain the target t‐sb‐PLAs with different block compositions. The resultant t‐sb‐PLAs with nonequivalent PLLA/PDLA compositions form stereocomplex crystals without homochiral crystallization. Their sc crystallinity and thermomechanical properties are dramatically improved by enantiomeric adjustment of PLLA‐rich t‐sb‐PLAs with PDLA‐rich t‐sb‐PLAs having complementary PLLA/PDLA composition.