环氧树脂改性水性聚氨酯的合成研究

采用甲苯二异氰酸酯(TDI-80)、聚醚二醇(N220)、二羟甲基丙酸(DMPA)、环氧树脂和丙烯酸羟丙酯(HPA),合成了环氧改性的双键封端水性聚氨酯乳液.乳液由于含有不饱和双键而具有感光性能,故此乳液可用作水性紫外光固化涂料或胶粘剂的预聚物.实验结果表明,随着环氧树脂用量的增大,涂膜的硬度、耐水性、耐溶剂性及力学性能增强,但乳液外观和稳定性变差,故适宜的环氧树脂添加量为4%～8%.通过傅立叶变换红外光谱、粒径分析仪、凝胶渗透色谱(GPC)和透射电镜(TEM)等对乳液进行了表征.粒径分析仪分析显示,加入环氧树脂后,水性聚氨酯(WPU)分散体粒径增大,粒径分布变宽.凝胶渗透色谱分析表明环氧树脂改性水性聚氨酯提高了聚氨酯的分子量.

Study on synthesis of water-borne polyurethane modified by epoxy resin

The waterborne polyurethane emulsion terminated with vinyl modified by epoxy resin was prepared using toluenediisocyanate(TDI),polyether(N220),dimethylolpropionic acid(DMPA),epoxy resin and hydroxypropyl acrylate(HPA).The emulsion has a photosensitivity owing to containing undersaturated double bonds,so it can be used as the prepolymer for UV-Curable waterborne coatings or adhesives.The experimental results showed that the hardness,water resistance,solvent resistance and mechanical property of WPU film increase with the increasing of the amount of epoxy resin,while the appearance and the stability of WPU emulsion deteriorate.So the suitable amount of epoxy resin is 4%-8%.The emulsion was characterized by FT-IR,malvern particle size analyzer,GPC and TEM.The particle size analyzer showed that the particle size of WPU increases and the particle size distribution becomes wide by adding epoxy resins.The GPC measuring found that the molecular weight of WPU modified by epoxy resin is higher than that of WPU.