端异氰酸酯基聚氨酯预聚体的合成与表征

Synthesis and characterization of isocyanate-terminated polyurethane prepolymer

以异佛尔酮二异氰酸酯(IPDI)和聚乙二醇2000(PEG2000)为单体,在二月桂酸二丁基锡(DBTDL)的催化作用下,通过逐步聚合反应合成了NCO封端的聚氨酯预聚体(PPU)。通过单因素实验分析法优化出了PPU合成条件:反应温度70℃,w(DBTDL)=0.75%(以IPDI和PEG2000的总质量计),反应时间为1.5h。利用FT-IR、1H-NMR等方法对单体和PPU的分子结构进行了表征,通过综合热分析测试了PPU的热分解温度Tg为268.2℃。

The isocyanate-terminated polyurethane prepolymer（PPU） is synthesized by step-growth polymerization using isophorone disocyanate（IPDI） with polyethylene glycol （Mw = 2000） as the monomers, and dibutyltin dilaurate（DBTDL） is used as the catalyst. The appropriate reaction conditions are optimized by single factor experiments for the PPU, which are as follows ： the reaction temperature of 70℃, the quantity of catalyst as 0.75 % of the materials, and the reaction time of 1.5 hours. The molecular structures of the monomers and PPU are characterized and analyzed by FT-IR, ^1H-NMR, and the thermal properties of PPU are characterized and analyzed by TGA, which shows the thermal decomposition temperature is 268.2℃.