底面合一阴极电泳涂料用乳液的制备及性能研究

Preparation and Properties of Emulsion for Primer-Topcoat Cathodic Electrodeposition Coatings

本文使用过氧化二苯甲酰(BPO)为引发剂,将丙烯酸树脂接枝到环氧树脂上,合成了丙烯酸接枝环氧树脂。探讨了环氧树脂的分子量、甲基丙烯酸缩水甘油酯(GMA)、仲胺和中和剂的用量对乳液性能的影响。结果表明:选择分子量适中的EP-3为环氧树脂、GMA用量为16 wt%、N-甲基乙醇胺(MMEA)按100%开环度开环、醋酸按45%的中和度中和时得到的乳液综合性能最佳,其粘度为45 KU,粒径为73.3 nm,50℃下的热储超过30天。与电泳专用色浆配套使用时得到的漆膜板面平整、硬度为H、附着力为0级,耐冲击大于1 kg·50 cm、耐候和盐雾均大于500 h。

An acry lic epoxy resin was synthesized by grafting acrylic resin onto epoxy resin using dibenzoyl peroxide(BPO) as initiator.The effect of molecular weight of epoxy resin,amount of glycidyl methacrylate(GMA),secondary amine and neutralizer on the properties of the emulsion was investigated.The results show that,when EP-3 with moderate molecular weight was selected as epoxy resin,the dosage of GMA is 16 wt%,the ring-opening degree of N-methyl ethanolamine(MMEA) is 100%,and the neutralization degree of acetic acid is 45%,the emulsion has the best comprehensive performance including a viscosity of 45 KU,the particle size of 73.3 nm,and a thermal storage at50℃ for more than 30 days.The prepared coatings formulated with special pigment pastes for electrophoresis exhibited a uniform and homogeneous surface with a hardness of H,an adhesion of grade 0,an impact resistance greater than 1 kg·50 cm,both weather resistance and salt spray were greater than 500 h.