摘要： 以离子型共聚单体苯乙烯磺酸钠与非离子型共聚单体甲基丙烯酸β-羟乙酯为功能单体,以K₂S₂O₈-NaHSO₃为氧化-还原体系,进行MMA-BA无皂乳液聚合研究。详细讨论了乳化剂用量、配比、反应温度、引发剂配比等条件对乳液聚合及共聚物性能的影响。并在纯丙无皂乳液聚合的研究基础上进行有机硅改性丙烯酸酯无皂乳液聚合研究,研究了有机硅的加入及加入顺序对乳液聚合及其性能的影响。结果表明:有机硅的加入使共聚物的耐水性提高,而且有机硅后加的聚合稳定性优于先加的。透射电镜表明有机硅先加得到的乳胶粒子为均匀的球形核壳结构,而有机硅后加得到的乳胶粒子形状不规则,且有机硅的加入使乳胶粒径减小。

关键词: 离子型单体, 无皂乳液, 有机硅改性, 硅丙乳液

Abstract: The soap-free polyacrylates emulsion polymerization was studied by using sodium 4-vinylbenzene sulfonate(Nass)as ionic comonomer and hydroxyethyl methacrylate(HEMA) as nonionic comonomer, methyl methacrylate (MMA )and butyl acrylate (BA) as copolymerization monomers and potassium persulfate( KSP)/ sodium bisulfite(SHS)as redox initiation system. The effects of the amount of the initiators, ionic/noionic monomer ratio, reaction temperature on the emulsion polymerization and the property of he emulsion were investigated in detail. On the basis of the study of all acrylates soap-free emulsion poly merization, polysiloxane modified polyacrylates soap-free emulsion polymerization was studied. The effect of incarporation of organosiloxane and the sequence of the organosiloxane incorporation on the properties of emulsion was also investigated. The results showed that water resistance was improved with the addition of organosiloxane. Moreover, polymerization stability was better when the organosiloxane was added at the end than that at the beginning. TEM test showed that the latex was uniform core-shell sphere structure when the organosiloxane was added at the beginning and the latex shape was irregular when the organosiloxane wasadded at the end. The particle diameter of polysiloxane-acrylates emulsion was smaller than that of the acrylales emulsion.

Key words: ionic monomer, soap-free emulsion, organosiloxane modification: organosiloxane-acry lates emulsion