苯乙烯-马来酸酐共聚物作乳化剂合成丙烯酸酯乳胶的研究

采用4种不同的碱(氢氧化钾、氢氧化钠、氨水、三乙胺)皂化低相对分子质量的苯乙烯-马来酸酐共聚物(SMA)作为乳液聚合的乳化剂合成了丙烯酸酯乳胶,并对4种不同碱皂化的SMA作乳化剂合成丙烯酸酯乳胶时所需乳化剂的用量、乳胶的粒径、粒径分布、黏度、乳胶稳定性及乳胶膜的吸水率进行了研究。结果表明:4种碱皂化SMA作为乳化剂均可以合成丙烯酸酯乳胶,最佳用量为单体的8%(质量分数,下同)。乳胶性能及乳胶膜的吸水率受皂化SMA所用碱的类型的影响较大。其中,NaOH皂化SMA作乳化剂合成的丙烯酸酯乳胶的综合性能最好,乳胶的粒径较小为142.4 nm,呈单分散,黏度为14.68 mPa·s,综合稳定性良好,乳胶膜吸水率较低,为9.52%。

Synthesis of Polyacrylate Latex with SMA Copolymer as Emulsifier

Acrylate latex was synthesized using the low molecular weight styrene-maleic anhydride（SMA）copolymer saponified by use of the bases of KOH，NaOH，NH₃·H₂O and TEA. The amount of the saponified SMA copolymers emulsifier used in emulsion polymerization， the particle size，particle size distribution，viscosity and stability of latex and the water absorption of latex film were investigated. It was shown that all of the above mentioned alkali saponified SMA copolymer could be used as emulsifier to synthesize acrylate latex and the best dosage was 8% of the monomers. The property and the water absorption of latex film were significantly influenced by the alkali used in the saponification reaction of SMA copolymer.The comprehensive properties of acrylate latex，prepared by using the SAM copolymers saponified via NaOH as emulsifier，was the best among them，the particle size of the latex was as small as 142 nm and monodisperse，its viscosity was 14. 68 mPa·s with excellent stability， the water absorbability of latex film was as low as 9. 52%.