乳液型环氧固化剂的制备与性能研究

Preparation and Properties of Emulsion Epoxy Curing Agent

为制备稳定性良好及高耐性的乳液型环氧固化剂,以三乙烯四胺、聚乙二醇二缩水甘油醚、环氧树脂E51、邻甲苯缩水甘油醚为原料合成了一种非离子反应型乳化剂(NIRE);以二乙烯三胺或间苯二甲胺、环氧树脂E20、苯基缩水甘油醚为原料合成了改性胺作为被乳化物(ES)。利用NIRE与ES之间的疏水性差异,通过相反转法制得乳液型环氧固化剂(WCA),并考察了WCA固化的水性双组分环氧底漆的应用性能。采用红外光谱表征了NIRE、ES的结构;探究了制备NIRE的最佳反应条件;并研究了NIRE用量、乳化温度、剪切速度对WCA性能的影响;以及ES结构中胺的种类及封端率对WCA应用性能的影响。结果表明:当NIRE质量为ES的25%,乳化温度为60℃,剪切速率为2 000 r/min时,可制得粒径小、稳定性良好的WCA,由其制备的水性双组分环氧底漆具有优异的附着力、耐水性和耐盐雾性。

In order to prepare emulsion epoxy curing agent with good stability and high resistance,a non-ionic reactive emulsifier(NIRE)was synthesized from triethylene tetramine,polyethylene glycol diglycidyl ether,epoxy resin E51 and o-cresol glycidyl ether.The diethylenetriamine or m-phenyldimethylamine,epoxy resin E20 and phenyl glycidyl ether were used to synthesize modified amines which was used as emulsified substances(ES).An emulsion epoxy curing agent(WCA)was prepared by reverse transformation based on the hydrophobicity difference between NIRE and ES,and the application performance of WCA-cured two-component waterborne epoxy primer was investigated.The structures of NIRE and ES were characterized by infrared spectroscopy.The optimum reaction conditions for NIRE,the effects of NIRE dosage,emulsification temperature and shear rate on the WCA properties,and the effects of amines type in ES structure and the sealing rate on the application performance of WCA were studied.The results showed that when the NIRE dosage was 25%of ES,the emulsification temperature was 60℃,and the shear rate was 2000 r/min,the obtained WCA had small particle size and good stability.The prepared two-component waterborne epoxy primer had excellent adhesion,water resistance and salt spray resistance.