水性涂料用自乳化环氧树脂乳液的制备方法

Preparation method of self-emulsifying epoxy resin emulsion used for water-based paint

研究了一种水性涂料用的自乳化环氧树脂乳液的制备方法,该水性环氧树脂乳液的制备无需外加乳化剂,经过对油溶性环氧树脂的改性,可实现自身乳化。由自乳化法制备的环氧乳液与水溶性固化剂配伍性好,漆膜性能佳,有效解决了传统外加乳化剂法制备的环氧乳液固化物分子质量低,易从漆膜中萃取出来,漆膜耐化学品性能差的问题。以酸酐为扩链剂,在环氧树脂上接上亲水基团,从而实现改性环氧树脂的水分散。研究得出选用环氧树脂E51、聚乙二醇600以及邻苯二甲酸酐为原料,制备的水性环氧乳液粒径仅为283 nm,储存稳定。重点探讨了反应时间、反应温度、反应物摩尔比、催化剂种类及用量对自乳化环氧树脂乳液的影响。

This article studies a method for preparing a self-emulsifying epoxy resin emulsion which used for water-based paint,it needs no external emulsifiers, after modified the oil-soluble epoxy resin,the modified epoxy resin can achieve self-emulsi- fying. Epoxy emulsion prepared by method of self-emulsifying has good compatibility with water-soluble curing agent and has good film properties,it effectively solved the problems of epoxy emulsion prepared by traditional external emulsifier, which has low molecular weight and can easily extracted from the paint film and the problem of poor film ehemical resistance. In this experi- ment we used anhydride as chain extender, attaching hydrophilic groups on the epoxy resin,in order to achieve an aqueous dis- persion of a modified epoxy resin. The study results that select E51 epoxy resin,PEG600,phthalic anhydride （PA） as rawmaterials, the particle of this waterborne epoxy emulsion is only 283 nm and has storage stability. In this experiment,it focuses on the influences of reaction time, temperature reflex, molar reactant ratio and the type and amount of catalyst on the experiment.