红外光谱法研究TDI-TMP固化剂的合成过程

Research of synthesis process of TDI-TMP curing agent by FT-IR

采用傅里叶变换红外光谱分析技术对甲苯二异氰酸酯(TDI)与三羟甲基丙烷(TMP)固化剂合成反应过程中的聚氨酯预聚物进行表征,分析原料谱图和合成过程中预聚物谱图,确定反应进程,探讨反应机理。TDI-TMP合成过程的红外光谱分析结果表明,虽然TMP是一种结构紧密空间不舒展的多元醇,但是在TDI大量过量时,-OH基在低温下通过延长反应时间是可以基本反应完全的。在优化的合成工艺条件下得到了分子质量小、黏度低的理想预聚物,该预聚物适合在薄膜蒸发器中进行游离TDI的分离。

The reaction process of toluene diisocyanate-trimethylolpropane（TDI-TMP） was tudied by means of Fourier transform infrared（FT-IR）. The FTIR analysis showed that although TMP was not stretching in space, in conditions of large excessive TDI and long reaction time, even if at low temperature, the hydroxyl groups of TMP almost reacted completely. Based on the experiment results, the TDI-TMP prepolymer with small molecular weight and low viscosity was obtained, and the prepolymer is more suitable for separating free TDI from TDI- TMP prepolymer with a thin-film evaporator.