Premium
Stereocomplex‐ and Homo‐Crystallization and Phase‐Transition Behavior of Relatively High‐Molecular‐Weight Linear One‐ and Two‐Armed and Star‐Shaped Four‐Armed Poly( l ‐lactide)/Poly( d ‐lactide) Blends
Author(s) -
Tsuji Hideto,
Sakamoto Yuzuru,
Arakawa Yuki
Publication year - 2017
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.201700286
Subject(s) - crystallite , crystallization , branching (polymer chemistry) , materials science , lactide , crystallography , polymer chemistry , isothermal process , chemistry , polymerization , composite material , organic chemistry , thermodynamics , physics , polymer
Relatively high‐molecular‐weight linear one‐ and two‐armed and star‐shaped four‐armed poly( l ‐lactide) and poly( d ‐lactide) are synthesized and the multiplicate effects of arm‐number (branching architecture, coinitiator moiety), crystallization temperature ( T c ), and number‐average molecular weight ( M n ) on stereocomplex (SC)‐ and homo‐crystallization and phase‐transition behavior are investigated. For nonisothermal and isothermal crystallization, in addition to SC crystallites, homo‐crystallites are formed in the blends with higher M n values, irrespective of arm number. For isothermal crystallization, the transition T c ranges below which in addition to SC crystallites, homo‐crystallites are formed depended on M n per one arm‐determining melting temperature or thickness of homo‐crystallites. The transition M n ranges above which in addition to SC crystallites, homo‐crystallites are formed are not affected by arm number. The high molecular weight disturbs the change of crystalline growth mechanism of one‐ and two‐armed blends, whereas the branching architecture inhibits the change of crystalline growth mechanism of four‐armed blends.