六甲氧基甲基三聚氰胺-多元醇-丙烯酸酯混杂聚合中酸的双重作用

六甲氧基甲基三聚氰胺 (HMMM) 多元醇 丙烯酸酯混合体系在较高温度下可同时进行缩聚和自由基聚合并表现出加速固化、热互补、原位形成高分子合金等协同效应 .通过凝胶化时间和聚合反应速度的研究 ,发现酸既是HMMM 多元醇缩聚反应的催化剂 ,也是促进过氧化氢物分解产生自由基引发丙烯酸酯自由基聚合的催化剂 .研究还发现 ,以潜酸催化剂作为酸的来源可以使体系达到室温稳定 ,高温快速固化的目的

EFFECT OF ACID ON THE HYBRID POLYMERIZATION OF HEXAMETHOXYMETHYL MELAMINE POLYOL-ACRYLATE

Compositions of hexamethoxymethyl melamine(HMMM)|polyol|acrylate can be cured by hybrid polymerization involving the condensation reaction of HMMM with polyol and the free radical polymerization of acrylate, with some synergetic effects such as the enhanced curing rate, energy compensation effect and the formation of polymer alloys in|situ. By investigating the gel time and the polymerization rate, it was found that the acid acts not only as the catalyst for the condensation reaction of HMMM with polyol, but also as the catalyst for the decomposition of the hydroperoxide, generating the initiating free radicals for the polymerization of the acrylate. It was also found that the use of the latent acid catalyst could greatly increase the shelf time of the hybrid polymerization system at room temperature, while maintaining the activity of the formulation at high temperature.