Study on synthesis and application of blocked waterborne polyurethane

A series of blocked aliphatic waterborne polyurethane emulsions were prepared with isophorone-diisocyanate(IPDI),polyether polyols,dimethylolpropionic acid(DMPA) as materials and NaHSO3 as blocking agent.The influencing factors of the pre-polymerization reaction,neutralization reaction and blocking reaction were investigated and the synthetic process conditions were optimized.Then the blocked aliphatic waterborne polyurethane(WPU) with better comprehensive properties were obtained.The WPU was used to anti-crease finishing of cotton fabric.The results showed that the wrinkle recovery angle of the treated fabric were increased and the strength retention were also enhanced.