新型磺酸型表面活性单体制备水性聚氨酯微乳液

Preparation of Novel Water Polyurethane Micro-Emulsions by Surface-Active Monomer of Sulfonic Acid Type

以聚(四氢呋喃-co-氧化丙烯)二醇为软段、异佛尔酮二异氰酸酯为硬段、1,2-二羟基-3-丙磺酸钠为亲水扩链剂,采用自乳化法合成了一系列新型磺酸型表面活性单体制备的水性聚氨酯(简称磺酸型WPU)微乳液;与羧酸型WPU微乳液进行了对比实验,对微乳液的粒子形态、粒径分布及微乳液的其他性能进行了研究。实验结果表明,磺酸型WPU微乳液的粒子呈球形,粒径呈多元分布;WPU微乳液具有假塑性流体的特征,表观黏度小于250mPa·s(剪切速率25s-1时),且表观黏度随剪切速率的变化规律呈现一定的"切力变稀"特征;相对于常规的羧酸型WPU微乳液,磺酸型WPU微乳液具有更高的固含量和更低的表面张力,且具有较好的低温、高温及室温稳定性。

A series of novel stable sulfonic acid type water polyurethane （WPU） micro-emulsions with sulfonate groups （abbreviated as ＂ sulfonic acid type WPU micro-emulsions＂ ） were prepared by self-emulsification. The said micro-emulsion was obtained by reaction of poly （tetrahydrofuran-co- propylene oxide ）glycol and isophorone isocyanate with sodium 1,2-dihydroxy-3-propanesulfonate （DHPA） as hydrophilic chain-extender. Morphology and microscopic properties of the micro-emulsion particles were analyzed and were compared with those of carboxylic acid type WPU micro-emulsions. The particles of obtained micro-emulsions were basically spherical with multi distributions in different particle size ranges. The obtained micro-emulsions behaved as a pseudo-plastic fluid, was less than 250 mPa . s in apparent viscosity （ at shear rate of 25 s^-1 ） and showed a characteristic of shear thinning. The obtained micro-emulsion presented higher solid-content and lower surface tension than these of traditional WPU micro-emulsion. Its stability at both high and low temperature was good.