无皂种子乳液聚合制备新型增稠剂

Abstract

采用无皂种子乳液聚合方法制备了一种新型丙烯酸酯共聚物增稠剂。为了获得表面清洁和表面富含羧基的功能性聚合物乳胶粒子，首先合成了种子颗粒直径在250~300纳米的聚(苯乙烯-甲基丙烯酸)(P(St-MAA))种子乳液；然后，在无乳化剂的条件下，聚合丙烯酸乙酯(EA)，甲基丙烯酸十二酯(LMA)，苯乙烯(St)和甲基丙烯酸(MAA)；最后，得到颗粒直径在380~440纳米的稳定乳液。重点研究了甲基丙烯酸十二酯含量对乳液颗粒大小和乳液稳定性的影响。研究表明，该聚合物乳液具有很好的增稠性能，良好的悬浮能力，透明性好，易于使用。采用傅里叶变换红外光谱仪(FT-IR)、示差扫描量热仪(DSC)、透射电子显微镜(TEM)对其结构和形貌进行了表征。 A kind of acrylates copolymer thickener was prepared by soap-free and seeded emulsion polymerization. In order to obtain functional polymer latex particles with clean surface and with surface carboxyl groups, Poly (styrene-methacrylic acid) (P (St-MAA)) seed particles with the diameter of 250 - 300 nm were synthesized via soap-free emulsion polymerization. Then the seeded emulsion copolymerization of ethylacrylate (EA), lauryl methlacrylate (LMA), St and MAA onto the seed particles were performed in the absence of emulsifier. The content of LMA effected for the particles size and the stability of the emulsion was studied. The thickening performance of this polymer latex was quite good with the high thickening performance, good suspension ability, good transparence and easy to use. The factors of the copolymerization and the properties of the emulsion were discussed. Its structure and morphology were characterize by fourier transform infrared spectrometer (FT-IR) and transmission electron microscope (TEM).