环氧改性水性聚氨酯及其常温储存性能研究

摘要

The waterborne polyurethane dispersion modified by different epoxy value of epoxy resin were synthesized by using isophorone diisocyanate(IPDI)and polyether glycol(N220)as main raw materi-als,dimethylolpropionic acid( DMPA) as hydrophilic chain extender. It was found that the tensile strength and microphase separation of WPU increased and the breaking elongation decreased with increas-ing in —NCO/ —OH(R value). The water absorption and breaking elongation of coating film decreased and the tensile strength of film increased after modified by epoxy resin. The tensile strength and breaking elongation increased after storage at normal temperature for 45 d.%采用两种不同环氧值的环氧树脂与异佛尔酮二异氰酸酯（IPDI）、聚醚二元醇（N220）和二羟甲基丙酸（DM-PA）反应，合成环氧改性水性聚氨酯分散体。研究发现，随着—NCO/—OH（R 值）的增加，胶膜的拉伸强度增大，断裂伸长率降低，微相分离程度增加；环氧树脂改性后胶膜的吸水率和断裂伸长率均降低，拉伸强度增大，随着环氧值的增大越加明显；常温贮存45 d，胶膜的拉伸强度和断裂伸长率均有增加。