聚硅氧烷改性水性聚氨酯的合成及其表面性能

以聚氧化丙烯二醇(PPG)、双羟基亲水性聚硅氧烷多元醇(UC3667)为软段,异佛尔酮二异氰酸酯(IPDI)、1,4-丁二醇(BDO)、二羟甲基丙酸(DMPA)、乙二胺(EDA)为硬段,制备了一系列聚硅氧烷改性水性聚氨酯(WPUs)。用DLS和FTIR表征了水性聚氨酯乳液粒径和膜结构。通过热重分析、拉伸测试、接触角测试、XPS对水性聚氨酯胶膜的性能进了测定。结果表明:随着聚硅氧烷加入量的增多,水性聚氨酯膜拉伸强度先增大后减小;且聚硅氧烷的加入提高了水性聚氨酯膜的热稳定性、断裂伸长率、接触角,降低了水性聚氨酯膜的表面能。当聚硅氧烷质量分数为5.0%时,胶膜表面的硅迁移量达到饱和,表面能为27.27 mJ/m~2。

Synthesis and Surface Properties of waterborne polyurethane modified by polysiloxane

Polyoxypropylene glycol (PPG),bihydroxy hydrophilic polysiloxane polyol(UC3667) as the soft segment,isophoronediisocyanate (IPDI), 1,4-butanediol (BDO), dimethylolpropionic acid (DMPA) and ethylenediamine (EDA)as the hard segment,a series of waterborne polyurethanes(WPUs)were prepared based on polysiloxane.The effect of polysiloxane on the particle size and stability of waterborne polyurethanes emulsion was investigated by Malvern laser particle size analyzer. The structure of waterborne polyurethane was characterized by infrared spectroscopy (FTIR), and the tendency of silicone to move to the surface of the film was analyzed. The thermal stability, mechanical properties and surface properties of waterborne polyurethane films were characterized by thermogravimetric analysis, contact angle and X-ray photoelectron spectroscopy. The results showed that when the content of polysiloxane increased, the tensile strength of waterborne polyurethane films increased firstly and then decreased; and the introduction of polysiloxane improved the thermal stability, elongation at break, contact angle of waterborne polyurethane films and reduced surface energy. Whenthe content of polysiloxane is 5.0%,polysiloxane migration on the surface of the film reached saturation, and the surface energy is 27.27 mJ/m2.