纳米二氧化硅/聚丙烯酸酯复合乳液的合成及其涂膜性能

Synthesis of nano-SiO_2/polyacrylate composite emulsion and its film performance

以改性硅溶胶与丙烯酸酯类单体原位聚合,采用单体预乳化、半连续滴加法制备了高硅含量纳米SiO2/聚丙烯酸酯复合乳液,研究了纳米SiO2和甲基丙烯酸(MAA)的用量、乳化剂配比和乳液固含量对乳液性能的影响,利用红外光谱、热重分析等方法对乳液结构和热稳定性进行了表征,测试了乳胶膜的性能。当SiO2用量为20%,乳化剂中m(OP-10):m(DNS-86)=1:3,功能性单体MAA用量为5%,乳液固含量为40%时,可制得稳定性良好的纳米SiO2/聚丙烯酸酯复合乳液,其涂膜硬度为6H,附着力1级,耐磨性达2500r,且具有良好的耐水性和耐热性。

A nano-SiO2/polyacrylate composite emulsion with high silica content was synthesized through in-situ polymerization of acrylate monomers with modified silica gel using the methods of monomers pre-emulsification and semi-continuous addition. The effects of the dosages of nano-SiO2 and methacrylic acid （MAA）, composition of emulsifier, and solid content of emulsion on emulsion properties were studied. The structure and thermal stability of emulsion were characterized by infrared spectroscopy and thermogravimetry, and the performances of emulsion film was tested. A nano-SiO2/polyacrylate composite emulsion with good thermal stability was prepared with 20% SiO2 and 5% MAA （as functional monomer） using an emulsifier composed of 1：3 （mass ratio） OP-10 and DNS-86 at a solid content of 40%. The emulsion film has the following properties： pencil hardness 6H, adhesion strength 1 grade, wear resistance 2 500 r, and good resistance to water and heat.