PU(U)A/SiO2杂化水分散液及成膜性能研究

用异佛尔酮二异氰酸酯(IPDI)、聚酯二元醇、二羟甲基丙酸(DMPA)、乙二胺、二乙醇胺、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸羟乙酯(HEMA)通过原位聚合方法合成了聚氨酯(脲)/聚丙烯酸酯水分散液,并且通过溶胶-凝胶方法合成了聚氨酯(脲)/聚丙烯酸酯/硅溶胶(PU(U)A/SiO2)杂化水分散液.杂化水分散液在pH值为7～11时的贮存稳定性大于1年;经高温、冻融试验后,无絮凝或沉淀出现,与PU(U)A水分散液相同.杂化膜的摆杆硬度、粘附力、耐吸水性、耐溶剂性比无硅溶胶的膜性能好.PU(U)A/SiO2杂化水分散稀溶液成膜后的透射电镜(TEM)结果表明,粒径为8～10nm的硅溶胶(SiO2)包覆在粒径 为50～200nm的PU(U)A粒子外围.ART-FTIR分析结果表明,杂化膜表面富含Si-O-Si官能团.AFM结果表明,与PU(U)A膜相比,杂化膜的硬区相畴尺寸变小.

The study of Pu(u) A/SiO2 hybrid water dispersions and films

Waterborne Polyurethane(urea)/polyacrylate (PU(U)A) dispersion was synthesized from 1 - iso-cyanato -3,3,5 - trimethyl - 5 - isocyanato - methyl - cyclohexane, dimethylol propionic acid, polyester polyol ( Mn = 2000g/mol, f = 2 ) , ethyldiamine, diethanol amine, methyl methacylate, butyl acrylate and hydroxyethyl methacrylate by using the in - situ polymerization, and PU ( U) A/SiO2 hybrid dispersion was obtained then by using the sol - gel process. The storage time of the hybrid dispersion was more than one year at pH 7 - 11. Its heat stability, freeze - thaw stability was just the same of PU (U ) A dispersion. The properties of the hybrid film, including hardness, adhesion, absorption of water and solvent resistance were better than those of the film without SiO2. TEM photograph of the PU ( U) A/SiO2 hybrid dispersion showed that the PU (U)A particles with the diameter of 50 -200nm was surrounded by silica particles with the diameter of 8 -10nm. ART - FTIR showed that the Si - 0 - Si groups enriched on the surface of the hybrid film. AFM revealed that, compared with the surface of PU(U) A film, the size of hard domains became smaller.