交联甲基丙烯酸甲酯/丙烯酸共聚微球羧基分布研究

Study on the partitioning of carboxyl group on crosslinked Poly(methyl methacrylate-acrylic acid) microspheres

用分散聚合法制备了交联甲基丙烯酸甲酯/丙烯酸(PMMA/AA)共聚微球,以电导滴定法研究了不同聚合反应条件对微球不同区域羧基分布的影响。研究结果表明增大配方中丙烯酸浓度或引发剂浓度,表面结合与被包埋的羧基含量增大,游离羧基含量降低;提高反应温度,表面结合羧基含量减小,被包埋的与游离羧基增大。 采用分散聚合法制备了交联甲基丙烯酸甲酯/丙烯酸(PMMA/AA)共聚微球,以电导滴定法研究了不同聚合反应条件对微球不同区域羧基分布的影响。研究结果表明增大配方中丙烯酸浓度或引发剂浓度,表面结合与被包埋的羧基含量增大,游离羧基含量降低;提高反应温度,表面结合羧基含量减小,被包埋的与游离羧基增大。

Crosslinked Poly(methyl methacrylate-Acrylic acid) microspheres were prepared by dispersion copolymerization of methyl mehacrylate and acrylic acid. It was studied that the effects of acrylic acid(AA) concentration、2,2?azobisisobutyronitrile(AIBN) concentration and reaction temperature on the partitioning of carboxyl group of the microspheres by conductance titration. It was found that the content of surface bound and buried carboxyl was increased and free carboxyl was reduced with an increase in AA and AIBN concentration ;raising reaction temperature increased the content of free and buried carboxyl and reduced the content of surface bound carboxyl.