离子场活化的GTP机理研究

Studies on Mechanism of GTP Activated by Ionic Field

关于基团转移聚合(GTP)机理先后有可逆离解、不可逆离解和络合等多种见解,但都与一些实验事实相矛盾,本文在前人研究的基础上提出了特殊离子场活化聚合机理. 1 离子场活化聚合机理 (1)在GTP过程阴离子催化剂通过产生“离子场”对所有引发剂分子活化,离子场总强度Q与有效催化剂摩尔浓度成正比.(2)离子场均等地影响引发剂分子上的硅原子,增强其亲电性,每个硅原子分享的场强Q_i与有效硅烷基总摩尔浓度n成反比,即Q_i=Q/n.(3)

On the basis of former studies found in literatures,the mechanism of group transfer polymerization (GTP) activated by ionic field was proposed.In this mechanism,initiator is activated by a special ionic field produced by anionic catalyst.The intensity of the field enjoyed by each molecule of imtiator(Qi) is directly proportional to total intensity of the field (Q) which is directly proportional to the equivalent concentration of catalyst,and is inversely proportional to the equivalent concentration of initiator (n),i.e.Qi=Q/n.Along as Qi reach a certain value,i.e.Qi≥Qmin,GTP will take place.Along with the raise of Qi value,activation extent of initiator increases,induction period of polymerization shortens,and the speed of polymerization increases.