复合型水性丙烯酸树脂乳液的制备和性能

Preparation and Properties of CompositeWaterborne Polyacrylate Resin Emulsion

采用低玻璃化转变温度、高分子量的丙烯酸树脂乳液与高玻璃化转变温度、低分子量的丙烯酸树脂分散体混合的方式,制备了无交联剂水性丙烯酸树脂复合乳液,用于彩印包装纸与塑料薄膜的热复合。以丙烯酸、丙烯酸丁酯、苯乙烯、丙烯酸羟乙酯等为原料,采用种子乳液聚合法制备了相对分子质量(1.48~1.84)×10^(5)、玻璃化转变温度(T_(g))﹣20~﹣40℃的丙烯酸酯乳液。以丙烯酸、丙烯酸丁酯、苯乙烯、α-甲基苯乙烯、马来酸单酯等为原料,采用本体聚合法制备了相对分子质量(1.34~1.65)×10^(4)、T_(g) 20~45℃、软化点80~105℃的固体树脂,进一步采用自乳化方法将固体树脂制备成树脂水分散体。考察了不同Tg的丙烯酸酯乳液与水分散体以不同比例混配后的乳液混合体的性能。研究结果表明,T_(g)为﹣27.6℃的丙烯酸酯乳液与Tg为28.2℃固体树脂的分散体以质量比8:2混合后,用于PET膜-黑色印刷纸的热复合,剥离强度达到5.6 N/25 mm,持粘性达270 h,可以充分满足覆膜材料的附着力和耐压纹等性能要求。

The water-based acrylic resin emulsion without crosslingking agent was prepared by mixing low glass transition temperature,high molecular weight acrylic resin emulsion and high glass transition temperature,low molecular weight acrylic resin aqueous dispersion,which was used for thermal lamination process of color printing packaging paper with plastic film.Using acrylic acid,butyl acrylate,styrene and hydroxyethyl acrylate as main raw materials,the acrylic emulsion with the molecular weight of(1.48~1.84)×10^(5) and glass transition temperature(Tg)of-20~-40℃was synthesized by seeding emulsion polymerization.The solid resin with molecular weight of(1.34~1.65)×10^(4),T_(g) of 20~45℃,softening point(SP)of 80~105℃was synthesized by bulk polymerization using acrylic acid,butyl acrylate,styrene,α-methylstyrene and maleate monoester.Furthermore,a self-emulsifying method was employed to prepare the aqueous dispersion of the solid resin.Properties of the acrylic emulsion with different Tg and the aqueous dispersions were investigated.The results show that when the acrylate emulsion(T_(g) of-27.6℃)was mixed with the solid resin dispersion(T_(g) of 28.2℃)at a mass ratio of 8:2,it could be used for thermal lamination of PET film and black printing paper.The peel strength reaches 5.6 N/25 mm,and the holding power reaches 270 h,which can fully meet the performance requirements of embossed laminating materials.