Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1401088 | European Polymer Journal | 2008 | 8 Pages |
Abstract
A series of novel ABC2-type liquid-crystalline block copolymers with azobenzene moieties in the side chains were prepared by combination of atom transfer radical polymerization (ATRP) and the chemical modification reaction. First, the bromine-terminated diblock copolymer poly(ethylene oxide) monomethyl ether-block-polystyrene (MPEO-PS-Br) was prepared by ATRP of styrene initiated with macroinitiator MPEO-Br, which was obtained from the esterification of MPEO and 2-bromoisobutyryl bromide. Then, the bromo end groups of the resulting MPEO-PS-Br were derivatized into twice as many bromoisobutyrates by the chain end modification reaction to obtain Ï,Ïâ²-bis(bromo)-PS-MPEO (MPEO-PS-Br2). The azobenzene-containing blocks of poly[6-(4-methoxy-azobenzene-4â²-oxy) hexyl methacrylate] (PMMAZO) with different molecular weights were introduced into the derivative diblock copolymer by a second ATRP to synthesize the novel ABC2-type liquid-crystalline block copolymers poly(ethylene oxide) monomethyl ether-block-polystyrene-block-{poly[6-(4-methoxy-azobenzene-4â²-oxy) hexyl methacrylate]}2 [MPEO-PS-(PMMAZO)2].
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Xiaohua He, Wuqiong Sun, Deyue Yan, Liyuan Liang,