乙酰乙酰基丙烯酸酯聚合物乳液的合成及室温交联改性

Synthesis and Ambient Crosslinking of Acetoacetate Acrylate Polymer Emulsion

采用半连续种子乳液聚合法合成了核壳型乙酰乙酰基丙烯酸酯聚合物乳液,并采用1,6-己二胺对其进行了室温交联改性。探讨了乳液聚合反应条件和交联单体甲基丙烯酸乙酰乙酰氧基乙酯(AAEM)用量对乳液及乳胶膜性能的影响。结果表明:当乳化剂十二烷基联苯醚二磺酸钠(DSB)、引发剂过硫酸钾(KPS)用量分别为单体总量的1.5%(wt)和0.5%(wt)时,单体转化率高,凝胶率低。透射电镜(TEM)分析显示乳胶粒呈明显的核壳结构,粒径约为130 nm。DSC、TGA和力学性能测试表明交联提高了乳胶膜的玻璃化转变温度、热稳定性及力学性能。随着AAEM用量的增加,乳胶膜的性能逐渐得到提高。当AAEM用量为单体总量的7%(wt)时,加入己二胺的乳液仍贮存稳定,可以单组分包装,并且交联后的乳胶膜性能优异。

A core-shell acrylate polymer emulsion containing acetoacetate group was synthesized via semi-continuous seeded emulsion polymerization, and the resulted polymer was crosslinked with 1,6-hexamethylenediamine at ambient temperature. The effects of polymerization condition and acetoacetoxyethyl methacrylate （AAEM） contents on the property of the emulsion and the latex films were discussed. The results indicate that the monomer conversion rate is high and the gel content is low when the content of the emulsifier （dodecyl diphenyl ether disulfonic acid sodium, DSB） and the initiator （potassium persulfate, KPS） was 1.5%（wt） and 0.5%（wt）, respectively. TEM analysis indicates that the latex particle has an obvious core-shell structure and the particle size is about 130 nm. DSC, TGA and mechanical property tests indicate that crosslinking enhances the glass-transition temperature, thermostability and mechanical properties of the latex films. These properties of the latex films are improved by increasing AAEM. When 7%（wt） of AAEM was used, the emulsion had good storage stability even 1,6-hexamethylenediamine was added into the emulsion. Therefore, the crosslinking process improves the performance of the obtained latex films.