含有磺酸基/羧基高固含量聚氨酯分散体的合成与表征

以磺酸盐聚醚二元醇(SPPG)作为软段亲水单体,DMPA作为硬段亲水单体,聚己二酸己二醇新戊二醇酯(PHNA)、异佛尔酮二异氰酸酯(IPDI)、六亚甲基二异氰酸酯(HDI)、三乙胺(TEA)、哌嗪为原料,采用丙酮法合成了固含量50%以上软硬段均含亲水的聚氨酯分散体(PUD)。研究表明,PUD的ζ电位处于-52～-72mV之间,具有良好的稳定性。亲水基团含量(HGC)、HDI/IPDI摩尔比的增加使胶粒平均粒径变小,粒径分布变窄,黏度增加;—SO3Na/—COOH摩尔比的减小,使小粒子体积分数在21%～28%,黏度显著减小。透射电镜(TEM)显示,分散体胶粒多为大小不一的球形结构,呈多元分布。DMA显示PUD胶膜具有良好的软硬段相容性和耐寒性。

Synthesis and characterization of high solid content polyurethane dispersion containing carboxylic and sulfonic groups

Polyurethane dispersions (PUDs) with solid content above 50% were synthesized by using polyether diol containing sulfonate (SPPG) as hydrophilic monomer in the soft segment, dimethylol propionic acid (DMPA) as hydrophilic monomer in the hard segment, poly(hexamethylene neopentylene adipate) (PHNA), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI) and piperazine by the acetone method.The results showed that the zeta potentials of PUDs were between -52 mV and -72 mV and the PUDs displayed excellent stabilization.The average particle sizes decreased, the particle size distributions narrowed and the viscosity increased when the hydrophilic group content and the mole ratio of HDI to IPDI increased.The viscosity evidently decreased when the mole ratio of -SO_3Na to -COOH decreased as a volume fraction of small particles between 21% and 28%.TEM analysis showed polydispersity and different sizes of the spherical particles.Dynamic mechanical analysis showed compatibility of soft and hard segments of the PUDs and a low glass transition temperature of the PUD film.