HMDI-IPDI型阳离子水性聚氨酯的合成及性能

以异佛尔酮二异氰酸酯（IPDI）、4,4_二环己基甲烷二异氰酸酯（HMDI）、聚醚二元醇（ PTMEG_2000）为单体,用N_甲基二乙醇胺作亲水扩链剂,制备阳离子型水性聚氨酯（ WPU）,并对其进行了红外光谱和粒径分析,主要探讨了影响阳离子水性聚氨酯固含量、断裂伸长率、吸水率的因素如混合二异氰酸酯摩尔比n （ IPDI/HMDI ）、预聚时二异氰酸酯与二元醇摩尔比n（二异氰酸酯/二元醇）、N_甲基二乙醇胺用量、三羟甲基丙烷用量和中和度.结果表明：当n（ IPDI/HMDI）在0.47：1与0.23：1之间时,所制得的阳离子型水性聚氨酯的固含量、断裂伸长率和吸水率均呈较稳定的状态；预聚阶段n（二异氰酸酯/二元醇）对WPU固含量影响不大,对断裂伸长率、吸水率影响明显；MDEA的用量对固含量、断裂伸长率和吸水率都有较深的影响；TMP的用量对WPU膜的固含量、吸水率及断裂伸长率影响一般；中和度对WPU固含量以及断裂伸长率的影响不大,但对吸水率影响较大.

Synthesis and Properties of Cationic WaterbornePolyurethane Based on HMDI-IPDI

Cationic waterborne polyurethanes have been synthesized by the step_growth polyaddition process of isophorone diisocyanate and dicyclohexylmethylmethane_4 ,4＇_diiso_cyanate and polyether dibasic alcohol with N_ methyl diethanolamine as hydrophilic chain extender. Infrared spectrum and particle size of WPU were analyzed. The influence of different factors affecting the solid content,breaking elongation,water absorption of the syn_thesized cationic waterborne polyurethane are discussed, including the mole ratios of iso_phorone diisocyanate and dicyclohexylmethylmethane_4,4＇_diisocyanate,the mole ratios of diisocyanates and diols during prepolymerization,the dosage of N_methyl diethanolamine, the dosage of trimethylolpropane and the neutralization degree. The results show that when n（IPDI/HMDI） lies between 0. 47：1 and 0. 23：1,the solid content,the breaking elonga_tion and water absorption are quite stable. The mole ratios of diisocyanates and diols during prepolymerization have little effect on the solid content while have an obvious effect on the breaking elongation and water absorption. The amount of MDEA has a deep influence on the solid content,the breaking elongation and water absorption. The amount of TMP has a small influence on the solid content, the breaking elongation and water absorption. The neutralization degree affects the solid content and breaking elongation slightly,but it has a greater impact on the water absorption rate.