Abstract:

Styrene-acrylic emulsion formulation system was designed. The effects of the glass transition temperature, types and ratio of emulsifiers as well as monomer-dropping method on the treeze-thaw stability of styrene-acrylic emulsion were discussed. The experimental results showed that the emulsion gave a balance of freeze-thaw stability and film-forming property when its T_g was 15. 7℃.In addition, the emulsion gave the optimal freeze-thaw stability when a synergy of anionic emulsifiers including sodium alcohol ether sulphate and allyloxy hydroxypropyl sodium sulfonate was used, optionally when the dosage of emulsifier was 1. 5% and the ratio of emulsifier in pre-emulsified and basic emulsion was 1: 1~2: 1, and optionally when a synergy of monomers including MMA and partial acrylate was used for the second monomer-dropping process.

Key words: styrene-acrylic emulsion, glass transition temperature, emulsifier, the second monomer-dropping process, freeze-thaw stability

摘要： 通过对苯丙乳液进行配方设计，考察了玻璃化温度，乳化剂类型、用量及配比和第 2 次滴加单体的组成对乳液冻融稳定性的影响。 乳液性能测试结果表明:乳液聚合物玻璃化温度为 15.7 °C 时，其冻融稳定性和成膜性能达到均衡;选择阴离子乳化剂脂肪醇聚氧丙烯醚硫酸钠和辅助乳化剂烯丙氧基羟丙基磺酸钠搭配，乳化剂占单体用量的 1.5%，预乳化液和打底液中乳化剂分配比例为 1 ∶1 ~ 2 ∶1，第 2 次滴加单体选择甲基丙烯酸甲酯和部分丙烯酸搭配，乳液冻融稳定性最佳。

关键词: 苯丙乳液, 玻璃化温度, 乳化剂, 第 2 次滴加单体, 冻融稳定性