水性聚酯改性聚氨酯的合成及其在水性涂料中的应用OA

Using isophorone diisocyanate(IPDI)as the isocyanate monomer,1,4-butanediol(BDO),2,2-bis(hydroxypropyl)propionic acid(DMPA)and synthesized dihydroxy disulfide(HEDS)as chain extenders,post-polymerization modification was performed on self-made side-chain polyether-type waterborne polyesters(WCPEs)to prepare a series of waterborne polyurethane dispersions(WPUDs)with molecular weights around 8× 103 and good storage stability.Ultraviolet(UV)-curable WPUD films were fabricated using 2-hydroxy-4-(2-hydroxyethoxy)-2-methylpropiophenone as the photoinitiator.Comparative studies with the commercially available waterborne polyurethane-based pigment wetting dispersant WQ-206 revealed that the synthesized WPUDs significantly enhanced pigment grinding efficiency,reduced pigment particle size and ink viscosity,improved pigment color development,and strengthened the anti-floating and anti-flocculation capabilities of the coating film.Additionally,leveraging the synergistic effect between residual double bonds in the main chain and the photoinitiator,the UV-cured nonionic polyurethane films exhibited high transparency and a markedly lower water absorption rate(≈6％)compared to traditional ionic polyurethanes(＞48％).Starting from molecular structure design,this study improved the application performance of polyurethanes through the synergistic optimization of nonionic side-chain architecture,incorporation of dynamic disulfide bonds,and UV-curing processes.The findings provide valuable guidance and reference for the development of multifunctional waterborne polyurethane materials.