UV固化超支化聚酯丙烯酸酯的合成及其固化性能

Synthesis and Curing Properties of UV Curable Hyperbranched Polyester Acrylate

以季戊四醇、2,2-二羟甲基丙酸、丁二酸酐和甲基丙烯酸羟乙酯为原料,合成一种新型UV固化超支化聚酯丙烯酸酯(HPA)。通过红外光谱、核磁共振谱表征了其结构;测试了相对分子质量及其分布和黏度;并考察了其紫外光固化性能。结果表明:在反应时间6 h、反应温度90℃、n[HP-(COOH)_8]∶n(HEMA)=1∶8时合成的HPA,当用4.5%的光引发剂1173引发固化时,UV辐照能量最小,为600 J/m^2,且固化速度比市售低聚物RJ544组成的相似体系快5倍,其双键的转化率可达89.8%。在制备的HPA经UV固化后,涂膜的铅笔硬度为2H,附着力为1级,柔韧性为0.5 mm。

A novel UV-curable hyperbranched polyester acrylate （HPA） was prepared by pentaerythritol （ PER）, 2,2-dimethylol propionic （ DMPA）, succinic anhydride （SA） and hydroxyethyl methylacrylate （HEMA）.The structure of HPA was characterized by IR, NMR, molecular weight and distribution as well as viscosity. The UV curing properties of HPA were investigated. The synthesis conditions of HPA showed that the optimum conditions were deter- mined as following： reaction time 6 h, reaction temperature 90 ~C, n [ HP-（ COOH）8] ： n（HEMA）= 1：8. When the optimum dosage of photoinitiator 1173 was 4. 5%, the radiation energy of HPA was the lowest, 600 J/m2. The curing speed of HPA was 5-time higher than that of the same system with normal commercial oligomers such as RJ544, the double bond conversion rate of HPA could reach 89.8%.The prepared HPA under the optimal conditions allows its cured film to show pencil hardness 2H, adhesion 1 grade and flexibility 0. 5 ram.