Abstract: a kind of epoxy-polyurethane cathodic electrophoretic coatings modified by castor-oil fatty acid with excellent bath stability good film performance and low curing temperature was prepared by using epoxy resin modified by dehydrated castor-oil fatty acid as binder and polyurethane prepolymer as crosslink-ing agent and proper additives in an optimal process. The effects of esterification degree, ring opening degree by amine, esterification temperature and sequence of synthesis steps on prepartion of resin were discussed.

Key words: epoxy resin, dehydrated castor-oil fatty acid, polyurethane prepolymer;electrophoretic coatings

摘要： 以脱水蓖麻油酸酯化改性的环氧树脂为主链，聚氨酯预聚物为交联剂，选择适当的合成工艺和助剂，制备出漆液稳定、漆膜性能好、固化温度较低的蓖麻油酸改性的环氧 －聚氨酯阴极电泳涂料。考察了酯化程度、胺开环率、酯化温度及工艺顺序等对树脂反应的影响。

关键词: 环氧树脂, 脱水蓖麻油酸, 聚氨酯预聚物, 电泳涂料