有机硅羧酸钠表面活性剂的合成及其应用研究

为提高农药的叶面展性和靶标生物作用率,设计合成双疏水链的有机硅羧酸钠表面活性剂.采用FT-IR光谱表征产物结构,用拉环法测定其表面活性.利用正交试验法优化硅氢加成反应条件,并将Si-H转化率最高的有机硅羧酸钠用作辛硫磷助剂.结果表明:低含氢硅油和丙烯酸单体投料摩尔比为1.00:1.02,氯铂酸催化剂加入量(以Pt计)为单体质量的0.03%,110 ℃下反应6 h制得的有机硅羧酸钠,Si-H转化率达87.8%.有机硅羧酸钠表面活性剂水溶液在298 K时的临界胶束浓度(c_mc)为4×10mol·L,最低表面张力(γ)为17.87 mN·m.1%质量浓度的辛硫磷溶液在树叶表面能完全铺展,主要是由于双疏水链的有机硅羧酸钠表面活性剂分子的加入.

The Synthesis and Application of Sodium Silicone Carboxylate

A series of sodium silicone carboxylate surfactants with double hydrophobic chain have been designed and synthesized to improve the spreadability of pesticide on the leaves and the utilization of the target organism.The structure of products have been characterized by FT-IR.The surfactivity of the sodium silicone carboxylate surfactants have been tested by pulling ring method.The best condition of hydrosilylation was optimized by orthogonal method and the silicone carboxylate surfactants with highest Si-H conversion rate are applied in phoxim solution.The results show that the sodium silicone carboxylate was obtained by the low hydrogen silicone oil and acrylic acid with the molar ratio of 1.00 to 1.02,with the catalyst(Pt dollars)of 0.03% in the mass of monomer with the temperature of 110 ℃ for 6 h as well as the conversion rate of Si-H is 87.8%.The critical micelle concentration(c_mc)and the surface tension of sodium silicone carboxylate surfactant is 4×10mol·L and 17.87 mN·m respectively.The 1% phoxim pesticide emulsion spread completely on the leaves which due to sodium silicone carboxylate surfactant with double hydrophobic chain be added.