羟烃基聚硅氧烷的制备及亲水性能

Preparation and Hydrophilic Properties of Hydroxyalkyl Polysiloxane

以八甲基环四硅氧烷(D4)、四甲基环四硅氧烷(D4^H)和六甲基硅氧烷(MM)为原料实施开环聚合反应,制备出不同含氢量的聚二甲基硅氧烷;含氢硅氧烷与乙酸乙烯酯进行硅氢加成反应,在硅氧烷大分子侧链上引入酯基;然后碱性条件下进行醇解反应,最后成功合成了不同羟烃基含量的聚硅氧烷。对产物的结构、乳化稳定性、乳液粒径及成膜的表面性能等进行了研究。结果表明,该方法可调控聚硅氧烷的羟烃基含量,改善聚硅氧烷亲水性能。当D4^H用量达到10%时,可获取粒径较小的水分散液,其亲水疏水平衡值(HLB)可达13,乳液稳定时间长达126 h。涂膜后与水的接触角可降低至70.7°。

A series of high molecular weight polydimethylsiloxanes with different hydrogen ratios were prepared by ring-opening polymerization of octamethylcyclotetrasiloxane(D4),tetramethylcyclotetrasiloxane(D4^H)and hexamethylsiloxane(MM).The hydrosilylation reaction of hydrogen-containing siloxane and vinyl acetate caused pendant ester groups to be introduced into the siloxane macromolecular chain.Then the alcoholysis reaction was carried out under alkaline conditions,and finally polysiloxanes with different hydroxyalkyl contents were successfully synthesized.The structure,emulsion stability,emulsion particle size and surface properties of the film were studied.The results show that the method can regulate the side group structure of polysiloxane to achieve hydrophilic modification.When the modified monomer reaches 10%,an aqueous dispersion with a smaller particle size can be obtained,and the hydrophilic and hydrophobic equilibrium(HLB)value can reach 13 and the emulsion stabilization time is as long as 126 h,the contact angle of water after coating can be reduced to 70.7°.