采用红外光谱、核磁共振、高分辨质谱对甲苯二异氰酸酯(TDI)与三羟甲基丙烷 (TMP)反应预聚物进行表征，并通过高效液相色谱 － 质谱联用追踪反应中各低聚物中间 体的含量，研究 TDI 和 TMP 的反应动力学． 研究表明:TDI-TMP 加成反应为二级反应;温 度对 TDI 中 2 位和 4 位—NCO 的反应选择性有显著影响，反应温度从 50℃升高到 80℃， 2 位—NCO 选择性从 0． 41 增加到 0． 64;在 80 ℃ 下，三步反应的反应速率常数分别为 0．18540、0．03789 和0．01140mol^-1 ·L^-1 ·min^-1 ，活化能分别为 12． 76、16． 58 和 25． 63kJ/mol， 反应第三步较前两步对温度更加敏感，故反应后期适当提高温度有利于反应的充分进行．

FT-IR,NMRand high-resolution MS were used to characterize the chemical structure of toluene diiso- cyanate (TDI)-trimethylolpropane (TMP) prepolymer,and HPLC-MS was adopted to detect the concentration of each oligomer in the reaction intermediates and to further reveal the reaction kinetics of TDI and TMP.The results indicate that (1) the TDI-TMP addition reaction is a second-order reaction; (2) temperature significantly affects the reaction selectivity of 2'-and 4'-NCO in TDI; (3) the 2'-NCO selectivity increases from 0. 41 to 0. 64 when the temperature increases from 50℃ to 80℃; (4) the reaction rate constants of the three steps of the reaction at 80℃ are 0. 18540,0. 03789 and 0. 01140mol^-1 ·L^-1 ·min^-1 ,respectively,with the corresponding activation energy be- ing 12. 76,16. 58 and 25. 63 kJ/mol,respectively; and (5) the third step of the reaction is more sensitive to temperature than the first two steps,so that appropriately raising temperature in the later reaction may result in a more sufficient reaction.