皮革用环保型聚氨酯发泡涂层的制备与性能

Preparation and Performance of Environmentally Friendly Polyurethane Foam Coatings for Leather

以聚酯二醇(PEG-2000)和异佛尔酮二异氰酸酯(IPDI)为主要原料,2,2-二羟甲基丙酸(DMPA)为亲水扩链剂,1,4丁二醇(BDO)为小分子扩链剂,三乙胺(TEA)为中和剂,水合肼(H6N2O)为后扩链剂,采用预聚体分散法合成耐水解聚酯WPU乳液。以硬脂酸铵为外乳化剂,对制备的乳液进行发泡处理,合成了固含量为50%的无溶剂环保型水性聚氨酯发泡涂层。探究反应指数(R,-NCO/-OH)、硬脂酸铵用量对WPU乳液和膜各项性能的影响,结果表明:当R值为1.7,硬脂酸铵用量为3%时,制备的涂层粒径较小、透气性佳,综合性能优良,满足工业化生产的质量要求。

With polyester diol(PEG-2000)and isophorone disocyanate(IPDI) as the main raw materials,2,2-dihydroxymethylpropionic acid(DMPA)as the hydrophilic chain extender,1,4-butanediol(BDO)as the small molecule chain extender,triethy-amine(TEA)as the neutralizer,hydrazine bhydrate(H6N2O)as the post chain extender,Hydrolysis resistant polyester WPU emulsion was synthesized by prepolymer dispersion method.Using ammonium stearate as external emulsifier,the emulsion was foamed and a solvent-free environment friendly waterborne polyurethane foam coating with solid content of 50%was prepared.The effects of the reaction index(R,-NCO/-OH)and the amount of ammonium stearate on the properties of WPU emulsion and film were investigated.The results showed that when R value was 1.7 and the amount of ammonium stearate was 3%,the coating had smaller particle size,better air permeability and excellent comprehensive performance,which can meet the quality requirements of industrial production.