环氧基水性固化剂的合成及其性能

Synthesis and Properties of Epoxy-based Water-borne Curing Agent

本文采用二乙醇胺(DEA)、丁二酸酐(SAA)、三乙烯四胺(TETA)和双酚A型环氧树脂(E-44)反应合成一种环氧基水性固化剂。该固化剂能稳定地分散在水相中,与乳液环氧树脂基体的相容性良好,固化涂膜的性能优异。采用红外光谱和核磁氢谱来研究反应历程,通过测定DEA、SAA、TETA转化率随时间的变化来确定最佳反应时间。研究原料配比E-44/DEA/SAA/TETA对固化剂性能的影响,结果表明:当E-44/DEA/SAA/TETA摩尔配比为3∶1∶3∶5.5时,固化剂综合性能最佳,固化剂水分散液的平均粒径约为40nm,水性固化剂与环氧乳液复配后制备的涂膜,光泽度为94Gs,铅笔硬度可达4H,弯折直径为2mm,冲击强度≥50kg·cm,附着力达到1级,表干时间为2h,与市售固化剂Anquamine 419固化涂膜的性能相当。

Epoxy-based water-borne curing agent was prepared using triethylene tetramine（TETA） and modified epoxy resin, which was synthesized by Bisphenol A type epoxy resin（E-44）, diethanol amine（DEA） and succinic anhydride（SAA）. The obtained curing agent possessed good water dispersibility and resin compatibility in epoxy emulsion, and the cured film was provided with excellent performances. Synthesis procedure of the curing agent was tracked by FTIR and ~1H-NMR. The optimum reaction time was determined by measuring conversion of DEA, SAA, TETA with prolongation of the reaction time. Effect of the molar ratio of E-44∶DEA∶SAA∶TETA on the performance of curing agent was investigated, the results show that the curing agent with excellent properties is obtained under the condition of the molar ratio of E-44∶DEA∶SAA∶TETA as 3∶1∶3∶5.5. The aqueous dispersion of the curing agent has an average particle size of 40 nm. Gloss, pencil hardness, flexibility, impact resistance, adhesion and surface drying time of the coating film are 94, 4 H, 1 mm, ≥50 kg·cm, level 1 and 2 h, respectively. The performance of self-made curing agent is comparable to Anquamine 419 curing agent.