有机硅表面活性剂在苯丙乳液合成中的应用

通过硅氢加成反应合成了有机硅表面活性剂(PSS),将其用作非离子型乳化剂,采用半连续预乳化聚合法制备了苯丙乳液。采用红外光谱和能谱分析对PSS进行结构表征,并测出其CMC为4.53×10-6 mol/L,浊点61～62℃。考察了PSS用量(即其质量占单体质量的百分数,1%～5%)对苯丙乳液性能的影响。结果表明:当w(PSS)=4%时,乳液聚合单体转化率可达98.65%,凝胶率降至0.87%,制成的苯丙乳液乳胶膜吸水率降至9.51%,消泡时间为18 s,比非硅乳化剂(烷基酚聚氧乙烯醚,OP-10)制成的苯丙乳液表面张力低,消泡时间短,乳胶膜吸水率低、拒水性好。

Application of polydimethyl silicone surfactant on properties of styrene-acrylate emulsion

Polydimethyl silicone surfactant(PSS) was prepared through hydrosilylation and then styrene-acrylate emulsion was synthesized by semi-continuous pre-emulsified polymerization,during the process of which PSS was used as emulsifier.IR analysis and EDS energy analysis were used to analyze the structure of PSS.The CMC was 4.53×10-6 mol/L and the cloud point was 61~62 ℃.The effect of PSS dosage(mass fraction,1%~5%) on the properties of styrene-acrylate emulsion was studied.The results show that,when w(PSS)=4%,the conversion rate of monomer could reach as high as 98.65%,the gelation rate could be reduced to 0.87%,the water absorption rate of the styrene-acrylate emulsion was decreased to 9.51% and the defoaming time was 18 s.These results indicate that,compared with the styrene-acrylate emulsion made with emulsifier without polydimethyl silicone(alkyl phenolic epoxy vinyl ether,OP-10),the target styrene-acrylate emulsion in this experiment has lower surface tension,shorter defoaming time,lower water absorption and better water resistance.