超支化聚氨酯丙烯酸酯的合成及其固化膜性能

Synthesis of hyperbranched polyurethane acrylates and properties of their cured films

以合成的甲苯-2,4-二异氰酸酯.丙烯酸羟丙酯(TDI.HPA)单体对超支化聚酯(HBPE)进行端羟基改性,得到超支化聚氨酯丙烯酸酯(HBPUA)。研究了反应温度、时间对产物游离—NCO含量的影响,通过摆杆硬度、附着力、柔韧性、冲击强度等测试研究了活性单体的种类及用量对固化膜性能的影响,并采用FT-IR及TG对HBPE,HBPUA及其固化膜进行了表征和分析。结果表明,合成HBPUA的最佳条件为:n(2,4-TDI):n(HPA):n(HBPE)=6:6:1,反应温度70℃,反应时间3 h,催化剂二月桂酸丁基锡(DBTDL)用量为总质量的0.6%;TDI.HPA的合成反应温度35℃,反应时间2.5 h,DBTDL用量为总质量的0.4%。采用己二醇二丙烯酸酯为活性单体并控制其质量分数为20%时,超支化聚氨酯丙烯酸酯涂膜的力学性能、热稳定性较好。

The hyperbranched polyurethane acrylates （HBPUA）were prepared by terminal hydroxyl mod- ification of hyperbranched polyester using synthesized 2, 4 - toluene diisocyanate hydroxypropyl acrylate （TDI · HPA）monomers. The effect of reaction temperature and time on the free -NCO contents of the products were studied. The active monomer kinds and amounts on the properties of UV cured film were in- vestigated by the testings of pendulum hardness, adhesion, toughness and impact strength. The HBPE, HBPUA and its cured film were characterize and analyzed by FT - IR and TG. The result showed that the best synthesis conditions of HBPUA were as followed： n（2, 4- TDI）：n （HPA）：n（HBPE） = 6：6 ： 1, rection temperature 70 ℃, reaction time 3 h, catalyst dilaurate tributyltin （DBTDL） amount 0. 6% （ based on the total mass）. The synthesis conditions of TDI · HPA were as followed ： reaction tempetature 35 ℃, reaction time 2. 5 h, DBTDL amount 0. 4%. The mechanical properties and thermal stability of coating films were better using hexanediol diacrylate as active monomer and mass fraction of 20%.