借助UV光聚合制备热塑性聚氨酯–聚苯乙烯嵌段共聚物

Preparation of thermoplastic polyurethane-polystyrene block copolymer by UV irradiation polymerization

采用端羟基的光引发剂2-羟基-2-甲基-1-苯基-1-丙酮（HMPP）封端聚氨酯预聚物，合成PUPI（一种聚氨酯大分子光引发剂），在紫外（UV）光照射下引发苯乙烯制备了聚氨酯-聚苯乙烯（PuPs）嵌段共聚物。采用实时红外、核磁共振和凝胶渗透色谱（6PC）对共聚物进行表征。通过考察苯乙烯转化率随时间的变化，发现uv光聚合可以在室温下进行。对PUPS嵌段共聚物的热力学性能和耐水性进行了研究，结果表明：聚苯乙烯链段的引入提高了聚氨酯的使用温度、拉伸强度，同时也提高了其耐水性能。

PUPI （a kind of polyurethane macrophotoinitiator） was synthesized by using the polyurethane prepoly- mer capped with the hydroxyl-terminated photoinitiator 2-hydroxyl-2-methyl-1-phenyl-l-propanone （HMPP）. The polyurethane-polystyrene （PUPS） block copolymer was prepared by initiating styrene under ultraviolet （UV） light ir- radiation. The copolymer was characterized by using the real-time infrared, nuclear magnetic resonance and gel perme- ation chromatography （GPC）. By investigating the change of styrene conversion rate with time, it was found that the UV irradiation polymerization can be carried out at room temperature. The thermodynamic performance and the water resistance of the PUPS block copolymer were investigated. The results show that the introduction of polystyrene seg- ment increases the end-use temperature and the tensile strength of the polyurethane, and also increases its water resis- tance performance.