硅酸四乙酯存在下的丙烯酸酯无皂乳液聚合

Free-soap emulsion polymerization of acrylates and tetraethyl silicate

在含烯丙基的特种醇醚硫酸盐和丙烯基乙醚磺酸钠盐反应型乳化剂存在下,将硅酸四乙酯与丙烯酸酯及偶联剂-甲基丙烯酰氧丙基三甲氧基硅烷进行无皂乳液聚合,有效地防止了原位生成的纳米二氧化硅粒子团聚,同时将其引入丙烯酸酯聚合物侧链形成潜在交联点,协同提高丙烯酸酯共聚物的耐水性和硬度。考察了硅酸四乙酯和硅烷偶联剂用量对无皂乳液聚合行为及乳液性能的影响规律。用该法制得的乳液比起常规方法,具有粒径小、均一度高、无小分子乳化剂杂质,且涂膜硬度高、膜透明度好、耐水性大幅度提高等优点。

The free-soap emulsion polymerization of tetraethyl silicate （TEOS） ,which can be hydrolyzed into nano silicon dioxide in the aqueous phase, acrylates and silane coupler-methacryloxypropyhrimethoxysilane is investigated in presence of the reactive emulsifier of allyl group alcohol ether sulfate salt and the propenyl group ethyl ether acid sodium salt. This method can prevent agglomeration of nano silicon dioxide prepared in-situ. The nano silicon dioxide can immediately react with silane coupler, with which the copolymer can be crosslinked during polymerization or film forming. This can enhance the water resistance and hardness of the film. The effects of contents of tetraethyl silicate and silane coupler to the behaviors and properties of the emulsion are discussed. Compared to the emulsion without TEOS and blending emulsion, this method has the advantages of smaller particle size, higher homogenization, no mini-moleculer emulsifier, and its film has higher hardness, higher transparence and excellent water resistance.