有机硅改性聚氨酯丙烯酸酯细乳液的研究

Research on Organosiloxane modified Polyurethane acrylate miniemulsion

以甲苯二异氰酸酯、丙烯酸羟乙酯、聚乙二醇为原料,合成了聚氨酯大单体;然后将其与甲基丙烯酸甲酯(MMA)、甲基丙烯酰氧丙基三甲氧基硅烷(DB-570)混合,制成预乳液,再滴加到聚丙烯酸丁酯(BA)种子乳液中,聚合成有机硅改性聚氨酯丙烯酸酯共聚细乳液。研究了DB-570用量、聚氨酯大单体的用量及类型、BA与MMA的质量比对细乳液性能的影响。结果发现,随着DB-570质量分数从2%增加到6%,细乳液的聚合及储存稳定性降低,乳胶粒的粒径及其分布指数逐渐增大;DB-570质量分数为4%时,细乳液的稳定性及乳胶粒的粒径大小及其分布最佳。随着聚氨酯大单体用量的增加,或聚乙二醇(PEG)摩尔质量的减小,细乳液乳胶粒的粒径及其分布指数增大;当聚氨酯质量分数为10%、其PEG摩尔质量为800g/mol时,细乳液乳胶粒的粒径最小、分布最窄;BA与MMA的质量比增大,细乳液乳胶粒的粒径随之缓慢减小,BA与MMA的最佳质量比为4∶1。

Firstly,the polyurethane macromonomer was synthesized by TDI,HEA and poly（ethylene glycol）（PEG）as raw material.Secondly,it was mixed with methyl methacrylate（MMA）and 3-（methacryloxypropyl）-trimethoxysilane（DB-570）to make the pre-emulsion.Thirdly,it was dropped into the seeded miniemulsion with butyl acrylate（BA）.The silicone modified polyurethane acrylate miniemulsion was thus prepared.The influence of the content of silicone monomer,the content and typies of polyurethane macromonomer,the ratio of BA to MMA on properties of miniemulsion were investigated.Results showed that when the content of silicone was changing from 2 to 6 percent,the particle size and particle size distribution gradually increased,and the stability of polymerization and storage of miniemulsion decreased.The optimum properties miniemulsion were achieved when the content of silicone was 4 percent.When the amount of the polyurethane macromonomer increased,or PEG＇s molecular weight deceased,the particle size and particle size distribution increased.When the content of polyurethane was 10 percent,the PEG＇s molecular weight was 800;the size of miniemulsion was the smallest with the narrowest distribution.The particle size decreased slowly,and the plasticity and flexibility increased with the ratio of BA to MMA increasing,and the properties of miniemulsion were excellent when the ratio was 4∶1.