影响环氧改性水性PUA乳液稳定性和耐水性的因素

以甲苯二异氰酸酯（TDI-80）、聚醚二醇（N220）、二羟甲基丙酸（（DMPA）、1，4-丁二醇（BDO）、环氧树脂E-20和丙烯酸羟丙酯（HPA）为主要原料，用三乙胺（（TEA）作中和剂、乙二胺（EDA）为扩链剂制备了环氧改性的水性聚氨酯-丙烯酸酯乳液，讨论了NCO／OH总摩尔比、DMPA含量、HPA含量、环氧树脂含量和中和度对乳液稳定性和耐水性的影响。结果表明，PUA乳液的耐水性随着NCO／OH总摩尔比和环氧树脂用量的增加明显增强，随中和度的增大而减弱；随着DMPA含量和中和度的增大，PUA乳液的外观和稳定性变好；当NCO／OH的总摩尔比为1．1～1．2，DMPA的含量为6％，环氧树脂的用量为4％～8％，以及中和度为90％～95％时，所得PUA乳液具有较好的稳定性和耐水性。

FACTORS INFLUENCING STABILITY AND WATER RESISTANCES OF WATERBORNE POLYURETHANE-ACRYLATE EMULSION MODIFIED BY EPOXY RESIN

The waterborne polyurethane-acrylate(PUA) emulsion modified by epoxy resin was prepared using toluene diisocyanate(TDI),polyether diol(N220),dimethylolpropionic acid(DMPA),1,4-butanediol(BDO),epoxy resin and hydroxypropyl acrylate(HPA) as the main materials,triethylamine(TEA) as the neutralizing agent and ethanediamine(EDA) as the chain extender.The influencing factors of the stability and water resistance of the emulsion,such as the total mole rate of NCO/OH,the DMPA content,the HPA content,the content of epoxy resin and the neutralization degree were discussed.The results showed the water resistance of the PUA emulsion had been obviously enhanced with the increase of the total mole rate of NCO/OH and the amount of epoxy resin,while weakened with the increase of neutralization degree.The appearance and the stability of the PUA emulsion had been improved with the increasing of the DMPA content and the neutralization degree.When the total mole rate of NCO/OH,the DMPA content, the usage of the epoxy resin and the neutralization degree are about 1.1~1.2,6%,4%~8% and 90%~95%,respectively,the PUA emulsion showed better stability and water resistance.