Synthesis of novel multi-arm star azobenzene side-chain liquid crystalline copolymers with a hyperbranched core

被引：35

作者：

He, XH ^{[1
]}

Yan, DY ^{[1
]}

Mai, YY ^{[1
]}

机构：

[1] Shanghai Jiao Tong Univ, Coll Chem & Chem Engn, Shanghai 200240, Peoples R China

来源：

EUROPEAN POLYMER JOURNAL | 2004年 / 40卷 / 08期

基金：

中国国家自然科学基金;

关键词：

liquid crystalline polymer; atom transfer radical polymerization; hyperbranched polymer; copolymer;

D O I：

10.1016/j.eurpolymj.2004.04.004

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

A series of novel multi-arm star side-chain liquid crystalline (LC) copolymers with hyperbranched core moieties were synthesized by atom transfer radical polymerization (ATRP) using a multi-functional hyperbranched polyether as the initiator and chlorobenzene as the solvent. The multi-functional hyperbranched polyether initiator was prepared from poly(3-ethyl-3-(hydroxymethyl)oxetane) (PEHO) and 2-bromo-2-methylpropionyl bromide. The azobenzene side-chain liquid crystalline arms were designed to have an LC conformation of poly[6-(4-methoxy-4'-oxy-azobenzene)hexyl methacrylate] with different molecular weights. Their characterization was performed with H-1 NMR, size exclusion chromatograph (SEC), differential scanning calorimetry (DSC) and thermal polarized optical microscopy (POM). The multi-arm star side-chain liquid crystalline copolymers exhibited a smectic and a nernatic phase, and the phase transition temperatures from the smectic to the nematic phase and from the nematic to isotropic phase increased with increasing the molecular weight of the multi-arm star side-chain liquid crystalline copolymers from 1.78 x 10(4) to 9.07 x 10(4). (C) 2004 Elsevier Ltd. All rights reserved.

引用

页码：1759 / 1765

页数：7

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