一种聚硅氧烷消泡剂的合成与应用研究

Preparation and application of polysiloxane defoamer

以氯铂酸为催化剂,烯丙醇聚氧乙烯聚氧丙烯醚(FB)、甲基丙烯酸十二烷基酯(LMA)和含氢硅油(PHMS)为原料,制得一种共改性硅油(PMS)。通过正交试验得到优化工艺条件为:n(Si-H)∶n(C=C)=1∶1.20,催化剂用量30μg·g-1,反应温度90℃,反应时间6 h,此条件下转化率达93.45%。采用高速剪切乳化搅拌方式将水相在油相中进行乳化,制备出聚硅氧烷消泡剂,由应用测试得到优化配方为:硅膏质量分数10%,PMS质量分数6%,复合乳化剂(m(Span 60)∶m(Tween 60)∶m(OP-10)=3∶2∶1)质量分数4%,制备出的聚硅氧烷消泡剂稳定性好,其消抑泡性能优于市售同类产品。

A kind of modified silicone oil （PMS） was synthesized by hydrosilylation with allyl alcohol polyethoxy polypropoxy ether （ FB ）, lauryl methacrylate （ LMA ） and hydrosilicone oil （ PHMS ） as starting materials, as well as chloroplatinic acid as catalyst. Optimum reaction conditions were investigated via orthogonal designed experiments as： molar ratio, n （ Si - H） ： n （ C = C ） = 1 ： 1. 20; dosage of catalyst, 30 μg · g-l ;reaction temperature,90 ℃ for 6 h. Under these conditions, the conversion achieves 93.45%. The polysiloxane defoamer was prepared by emulsifying of aqueous phase into the oil phase, which was composed of silicone oil paste, blended emulsifying agent and the prepared PMS in a high speed shearing emulsification mixer. The optimized formulation was obtained via application tests as：mass fraction of silicone oil paste, 10% ;mass fraction of PMS,6% ;and mass fraction of blended emulsifying agent （composed of Span 60,Tween 60 and OP- 10 with mass ratio of 3：2：1 ）, 4%. The polysiloxane defoamer product shows good stability and its defoaming property and foam inhibition property is superior to other similar products.