加核型超支化聚氨酯丙烯酸树脂的合成及涂膜性能研究

Synthesis of UV curable hyperbranched polyurethane acrylate with core and its film performance

选用甘油为核,二乙醇胺(DEOA)和异佛尔酮二异氰酸酯(IPDI)为原料,引入扩链剂新戊二醇(NPG),制得含扩链剂的端羟基加核型超支化聚氨酯(HBPU-OH);进一步与半加成产物IPDI-HEA反应,引入端丙烯酸双键,制得三端羟基的加核型超支化聚氨酯丙烯酸酯(HBPUA),并对其进行表征。FT-IR及NMR测试表明成功合成了HBPUA;DSC测试表明HBPUA的玻璃化转变温度(Tg)比HBPU-OH的低。含三端羟基的超支化聚氨酯丙烯酸酯(HBPUA-N-3)与目标树脂的相容能力更好。涂膜性能测试表明当HBPUA-N-3加入量为10%时,复合涂膜柔韧性和附着力没有明显变化,柔韧性≤2,附着力为2级;铅笔硬度和抗冲击强度都有明显提高,铅笔硬度为3H,抗冲击强度是50MJ/cm^2。

Hyperbranched polyurethane（HBPU-OH）were synthetized from glycerol as the core,diethanolamine（DEOA）,isophorone diisocyanate（IPDI）and neopentyl glycol（NPG）as the extension chain,which endcapped by multiple hydroxyl groups.The hyperbranched polyurethane acrylate with three terminal hydroxyl groups（HBPUA-N-3）containing urethane groups and acrylic double bonds was synthesized by the reaction of HBPU-OH and the semiadduct isocyanatehydroxyethyl acrylate（IPDI-HEA）.FT-IR and NMR indicated that HBPUA was successful synthetized.DSC results instructed that glass transition temperature of HBPUA-N-3was significantly lower than corresponding HBPU-OH.The compatibility test results showed that the compatibility of HBPUA-N-3with target resin was better.Paint films performance test showed that when the addition of HBPUA-N-3was 10%（wt）,the flexibility was equal or less than 2grade and adhesion 2grade.However,the pencil hardness and impact strength of composite coating film were significantly improved,namely 3H,50MJ/cm2 respectively.