硅基和氨酯基协同改性水性丙烯酸树脂的制备与性能

Preparation and properties of waterborne acrylic resin synergistic modification by silicon and polyurethane groups

以γ-巯丙基三乙氧基硅烷(TMPS)、异佛尔酮二异氰酸酯(IPDI)、甲基丙烯酸羟乙酯(HEMA)为原料合成了含硅聚氨酯小分子预聚体(IPDI-Si)。接着,以丙烯酸酯类单体为原料与IPDI-Si共聚,异丙醇(IPA)为溶剂,偶氮二异丁腈(AIBN)为引发剂,制备出改性树脂聚合物。然后,以三乙胺为中和剂,加水乳化制备了一系列巯基硅聚氨酯改性水性丙烯酸树脂分散体。采用FTIR、XPS、TGA、TEM、SEM等对分散体及树脂膜材料进行了表征,并测试了分散体的贮存稳定性及胶膜的硬度、附着力等性能。结果表明,当IPDI-Si含量为3%(以聚合单体的总质量为基准,下同)时,树脂分散体贮存稳定性较好,涂膜性能最佳;涂膜的致密性优异,硬度为2H,附着性为1级,水接触角96.1°。涂膜的拉伸强度达到9.4 MPa,断裂伸长率为385%;热失重分析表明,质量损失10%时的热分解温度(T10%)达到306.1℃。

Silicon-containing polyurethane pre-polymer(IPDI-Si)was prepared fromγ-mercaptopropyltriethoxysilane(TMPS),isophorone diisocyanate(IPDI)and hydroxyethyl methacrylate(HEMA).Then,a series of silicon-containing polyurethane modified acrylic resin polymers with different content of IPDI-Si were prepared with isopropyl alcohol(IPA)as solvent and 2,2′-azobis(2-methylpropionitrile)(AIBN)as initiator.Finally,a series of waterborne acrylic resin dispersions were prepared by emulsification with triethylamine as neutralizer in the presence of water.The dispersions and cured resin coatings were characterized by FTIR,XPS,TGA,TEM and SEM.And the storage stability of the dispersions,the hardness,adhesion and other properties of the coatings were tested.The results showed that when the IPDI-Si content was 3%(based on the total mass of polymerized monomers,the same below),the prepared dispersion had better storage stability and excellent resin coating performance.The prepared coating exhibited good compactness.The hardness was 2 H and the adhesion was grade 1.The water contact angle was 96.1°.And the tensile strength of the coating was 9.4 MPa and elongation at break reached 385%.The thermogravimetric analysis demonstrated that the temperature at which 10%mass loss(T10%)of the coating reached 306.1℃.