St/BA/DBMPA无皂阳离子共聚物乳胶粒研究

Study on the soap-free cationic copolymer latex particles of St/BA/DBMPA

选用苯乙烯 (St)、丙烯酸丁酯 (BA)和少量的反应性阳离子共聚单体N ,N -二甲基 ,N -丁基 ,N -( 3-甲基丙烯酰胺基 )丙基溴化铵 (DBMPA) ,以阳离子自由基型引发剂引发进行无皂乳液聚合 ,合成了稳定的无皂阳离子共聚物St BA DBMPA乳液 .研究结果表明 :增大阳离子单体浓度、引发剂浓度和主单体St BA体积比 ,共聚物乳胶粒粒径减小 ,粒子数目增大 ;增大离子强度 ,粒径呈现一个增大—减小—增大的变化过程 ;粒子的表面电荷密度也由以上 4个因素决定 .所合成的乳液表面张力小 ,耐电解质和耐有机溶剂性能好 ,说明该乳液具有很高的化学稳定性 .胶膜经高温处理后 。

Soap-free emulsion copolymerization of styrene (St) and butyl acrylate (BA) in the presence of active cationic comonomer N, N-dimethyl,N-butyl,N-(3-methacrylamidino) propyl ammonium bromide (DBMPA) was carried out using AIBA as initiator. The result showed: the average diameter of copolymer particles (Dw), decreased and number (N p) of copolymer particle increased with increasing DBMPA and AIBA concentrations, BA content in the St/BA monomer feeding. But Dw showed a change process of increase-decrease-increase with increasing ionic strength. Moreover, the surface charge density of the particles were decided by the DBMPA content, AIBA content, St/BA mass monomer ratio and ionic strength. The surface tensions of copolymer emulsion were little, the properties of electrolyte-resistant and CH 3OH- resistant of emulsion were good and there were high chemical stabilities of copolymer emulsion. The water-resistant property of film were to be improved after high temperature and DBMPA crosslinking.