磺酸盐/羧酸盐复合型阴离子水性聚氨酯分散体稳定性能研究

摘要

使用一种接枝磺酸钠基团的水溶性磺酸盐聚酯多元醇BY3301,将不同比例的磺酸钠引入到聚氨酯分子的软段上,制备了一系列磺酸盐/羧酸盐复合型阴离子水性聚氨酯分散体.使用红外光谱、透射电子显微镜和稳定性分析仪等手段表征了磺酸盐/羧酸盐复合型阴离子水性聚氨酯的结构、乳胶粒子的形态,研究了磺酸基团及其用量对水性聚氨酯乳液分散体稳定性的影响规律.结果表明:磺酸钠基团的引入使得分散体中的乳胶粒子形成具有更加规整的球形结构;当保持离子基团总量(HGC,即BY3301的磺酸钠基团和2,2-二羟甲基丁酸中和过的羧酸基团的离子当量)不变时,随BY3301用量的增加,其制备的复合型水性聚氨酯具有更高的Zeta电位、更好的高温稳定性及冻融稳定性.%A series of sulfonate/carboxylate acid composite anionic waterborne polyurethane(WPU)dispersions were prepared by employing sulfonate polyesterglycol (BY3301)to partially replace hydrophilic chain extender dimethylol butanoic acid(DMBA).Fourier transform infrared spectroscopy(FT-IR),transmission electron microscopy (TEM)and turbiscan lab stability analyzer were used to characterize the structure of WPU and shape of emulsion particle. The effect of sodium sulfonate group on the stability of WPU emulsion was studied in detail. The results showed that introducing sodium sulfonate groups endowed the latex particles with more regular spherical structure. When the content of total hydrophilic groups(HGC,i.e.sodium sulfonate group of BY3301and quaternary ammonium carboxylate group of neutralized dimethylol butanoic acid,DMBA)remained no change,the obtained composite anionic WPU film with higher BY3301content exhibited higher Zeta potential,superior high-temperature stability and freezethaw stability.