Substituent effects in the catalytic chain transfer polymerization of 2-hydroxyethyl methacrylate

被引：18

作者：

Biasutti, JD ^{[1
]}

Roberts, GE ^{[1
]}

Lucien, FP ^{[1
]}

Heuts, JPA ^{[1
]}

机构：

[1] Univ New S Wales, Ctr Adv Macromol Design, Sch Chem Engn & Ind Chem, Sydney, NSW 2052, Australia

来源：

EUROPEAN POLYMER JOURNAL | 2003年 / 39卷 / 03期

基金：

澳大利亚研究理事会;

关键词：

catalytic chain transfer; 2-hydroxyethyl methacrylate; substituent effects; cobaloxime; free-radical polymerization;

D O I：

10.1016/S0014-3057(02)00251-3

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

The catalytic chain transfer behavior of 2-hydroxyethyl methacrylate (HEMA) was studied in bulk at 40 and 60 degreesC. The chain transfer constant of cobaloxime boron fluoride (COBF) was found to be 6 x 10(2) at 40 and 60 degreesC, which corresponds to chain transfer rate coefficients of about 1.2 x 10(6) and 2.0 x 10(6) l mol(-1) s(-1), respectively. These values are about 10-15 times lower than those found previously for methyl methacrylate (MMA) and this decrease can be conceivably ascribed to the combination of a monomer viscosity effect, which lowers the rate coefficient by a factor of 6-8, and the complexation of the hydroxyl group with the catalyst, which causes an additional lowering by a factor of about two. The latter effect was studied by UV/Vis spectroscopy and additional kinetic studies of the COBF-mediated polymerization of MMA in the presence of ethanol. Similar UV/Vis spectra as in the case of HEMA and a reduction in chain transfer constant by a factor of two were observed. (C) 2002 Elsevier Science Ltd. All rights reserved.

引用

页码：429 / 435

页数：7

共 44 条

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