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在四个不同的温度下研究了四氢呋喃聚醚（ＰＴＭＧ），三羟甲基丙烷混合多元醇和甲苯二异氰酸酯（ＴＤＩ）的反应。无论是催化的还是非催化的反应，异氰酸根和羟基的反应均遵循二级反应力学，但４－位和２－位异氰酸根具有不同的反应活性。计算了４－位，２－位异氰酸根分别和羟基反应的速度常数ｋ１，ｋ２。活化参数Ｅａ１，Ｅａ２，△≠Ｓ１，△≠Ｓ２。随着反应体系的温度升高和催化剂ｍ－乙氧基三苯基铋（ｍ－ＯＥＴ－ＴＰＢ）的加入，ｋ１／ｋ２的比值减小。
The reaction of tetrahydrofuran polyether (PTMG), trimethylolpropane mixed polyol and toluene diisocyanate (TDI) was investigated at four different temperatures. The reaction between isocyanato and hydroxyl follow the second-order reaction mechanics, whether catalytic or non-catalytic reaction, but the 4-position and 2-position isocyanates have different reactivity. The rate constants k1 and k2 of 4-position and 2-position isocyanates reacting with hydroxyl groups were calculated. Activation parameters Ea1, Ea2, △ ≠ S1, △ ≠ S2. With the increase of reaction temperature and the addition of m-ethoxy triphenyl bismuth (m-OET-TPB), the ratio of k1 / k2 decreases.