酮肼交联体系在阴极电泳涂料中的应用

Application of diacetone acrylamide(DAAM) and adipic dihydrazide (ADH) crosslinking system in cathodic electrodeposition coating

使用苯乙烯、丙烯酸酯单体以及功能单体甲基丙烯酸缩水甘油醚(GMA)和交联单体双丙酮丙烯酰胺(DAAM)对中分子量的环氧树脂(E-20)进行接枝改性,并对改性的环氧树脂进行胺化、酸化、自乳化处理,从而制备出含有活性酮羰基的阳离子型乳液;以此乳液为基本成膜物质,选用己二酰肼(ADH)与体系中酮羰基进行交联,并进一步加入少量水性的封闭多异氰酸酯交联剂,配制出一种双重交联体系的阴极电泳涂料。详细研究了酮羰基与己二酰肼(ADH)在阴极电泳涂料中的交联反应能力,以及酮肼交联与多异氰酸酯交联体系的配比对涂料性能的影响,优化了涂料电泳、固化工艺,使制备的阴极电泳涂层具有固化温度低、硬度高、耐腐蚀性优良的特点。

A cathodic electrodeposition （CED） coating, which had many superior performance, such as high hardness, excellent corrosion resistance and low curing temperature, was developed from a modified epoxy resin emulsion grafted from styrene （St）, GMA, DAAM and other acrylic monomers through solution polymerization. A dual-crosslinking system was employed to improve the performance of the coating and decreased the dosage of more expensive blocked isocyanate chemical. The crosslinking reactivity of ADH and DAAM in CED as well as effects of varying dosage of crosslinking agent on the properties of coating were investigated.