Easy Access to the RAFT Equilibrium Constant

被引：26

作者：

Barth, Johannes ^{[1
]}

Buback, Michael ^{[1
]}

Meiser, Wibke ^{[1
]}

Vana, Philipp ^{[1
]}

机构：

[1] Univ Gottingen, Inst Phys Chem, D-37077 Gottingen, Germany

来源：

MACROMOLECULES | 2010年 / 43卷 / 01期

关键词：

ADDITION-FRAGMENTATION CHAIN; LENGTH-DEPENDENT TERMINATION; FREE-RADICAL POLYMERIZATION; RATE COEFFICIENTS; RATE RETARDATION; PLP-ESR; HOMOPOLYMERIZATIONS; KINETICS; STYRENE;

D O I：

10.1021/ma902111z

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 method is presented for determination of reliable values of the equilibrium constant K-eq between propagating radicals (P-center dot) and intermediate radicals (INT center dot) in reversible addition-fragmentation chain transfer (RAFT) polymerization. The technique is based oil EPR measurement of the ratio of concentrations of the two radical species Under quasi-equilibrium conditions ill low RAFT agent contents. The method requires no calibration of the EPR Setup for absolute radical concentration measurement. [Data for butyl acrylate polymerization mediated by benzyl propyl trithiocarbonate are presented. The value Of K-eq at - 40 degrees C was determined to be (1.0 +/- 0.1) x 10(4) L mol(-1).

引用

页码：51 / 54

页数：4

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