环氧树脂改性含硅自消光水性聚氨酯树脂的制备及性能

Preparation and properties of self-matting waterborne polyurethane with silicon modified by epoxy resin

以聚己二酸-1,4-丁二醇酯二醇(PBA)、异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)、1,4-丁二醇(BDO)、端羟丙基聚二甲基硅氧烷(PDMS)为单体合成聚氨酯预聚体,然后以三乙胺(TEA)为中和剂,乙二胺(EDA)为后扩链剂,合成了一系列环氧树脂改性含硅自消光水性聚氨酯树脂乳液。采用粒度分析仪测定乳液粒径,FTIR表征胶膜表面结构,SEM观察胶膜表面,并分析了胶膜的60°光泽度、水接触角、热力学等性能。结果表明,在n(PBA)∶n(PDMS)=1∶2的条件下,环氧树脂E-51添加量5.0%(以预聚体总质量为基准,下同)时,乳液粒径为1152nm,胶膜60°光泽度为3.4;水接触角平均值为107.3°,疏水性能最优;胶膜拉伸强度可达24.42 MPa,断裂伸长率在362%,力学性能最优;胶膜热失重50%时温度较未添加E-51的胶膜提高了18.3℃。

Polyurethane prepolymer was synthesized from poly(1,4-butanediol adipate)(PBA),isophorone diisocyanate(IPDI),dimethylolpropionic acid(DMPA),1,4-butanediol(BDO)and hydroxypropyl terminated polydimethylsiloxane(PDMS).Then,a series of silicone-containing self-matting waterborne polyurethane emulsions were synthesized with triethylamine(TEA)as neutralizer and ethylene diamine(EDA)as post chain extender by addition of epoxy resin into the polyurethane prepolymer.The particle size of emulsion was measured by particle size analyzer.The films were characterized by FTIR and SEM.The properties such as 60°gloss,water contact angle and thermodynamics of the films were analyzed.The results indicated that under the conditions of n(PBA)∶n(PDMS)=1∶2,additive amount of epoxy resin E-51 of 5.0%(based on the total mass of the prepolymer,the same below),the particle size of the prepared emulsion was 1152 nm,the 60°gloss and the average water contact angle of the corresponding film was 3.4 and 107.3°.Furthermore,the film showed the best hydrophobicity and mechanical properties.The tensile strength was 24.42 MPa and the elongation at break was 362%.The thermal decomposition temperature at 50%mass loss of this film was 18.3℃higher than that of the unmodified polyurethane film.