反应介质对催化链转移聚合反应的影响探究

采用催化链转移聚合法制备得到了端基带双键的聚甲基丙烯酸甲酯(PMMA)大分子单体,通过红外吸收光谱(FT-IR)、核磁共振氢谱(1HNMR)对大分子单体的结构进行了表征,并用凝胶渗透色谱法(GPC)测定了大分子单体的分子量及分子量分布;首次利用碘值法测定了大分子单体的双键含量。实验过程中考察了反应介质及其含量对大分子单体的分子量的影响,结果表明由于催化链转移剂与反应溶剂的络合作用,大分子单体的数均分子量随溶剂含量的增加而变大。

The Influence of Reaction Media on the Catalytic Chain Transfer Polymerization

Polymethyl methacrylate （PMMA） macromonomer with chain terminal unsaturated groups was prepared via catalytic chain transfer polymerization （CCTP）. Infrared spectroscopy （IR） , H - nuclear magnetic resonance （IHNMR） had been used to characterize the structure of the macromonomer; the average molecular weight and polydispersity index （PDI） of the macromonomer was measured by gel permeation chromatography （GPC） ; iodine value method was used to determine the content of the double bond, which was not reported before. The effect of the reaction media and the media content on the number average molecular weight （Mn） of polymethyl methacrylate macromonomer was investigated. The results showed that because of the complexation of solvent and chain transfer agent, the number average molecular weight of increased with the growth of the solvent content .