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综述了氨基甲酸酯（ＵＴ）和脲（ＵＡ）的自发反应和叔胺催化、有机锡催化、锡－胺协同催化反应的机理与动力学，以及反应介质、有机酸、水解氯、活泼氢组分分子结构及反应体系相态对反应的影响。ＵＴ和ＵＡ的生成反应存在产物催化现象。反应机理不仅与催化剂的性质有关，而且与反应物的结构和溶剂的性质有关。近期对反应注射成型体系的研究表明，相分离在聚合过程的早期发生，此后反应转为扩散控制。ＵＡ生成反应的动力学行为受相态的影响更甚。总包反应动力学可总结为ｄ［Ｕ］／ｄｔ＝Ａ０［ＡＨ］ｍ［ＮＣＯ］·ｅｘｐ（－Ｅａ／ＲＴ）。式中指前因子Ａ０与反应条件有关，活化能Ｅａ与反应物结构有关。［ＮＣＯ］为异氰酸根的浓度，［ＡＨ］为活泼Ｈ物质如羟基或ＮＨ２基的浓度，ｍ为与ＡＨ有关的反应级数。对ＵＴ生成反应，ｍ＝０．５～１。对ＵＡ生成反应，ｍ＝１～２，ｍ越接近２，产物催化作用越大。
The spontaneous reactions of carbamate (UT) and urea (UA) and the mechanism and kinetics of tertiary amine catalysis, organotin catalysis and synergistic catalysis of tin - amine were reviewed. The reaction media, organic acids, hydrolyzed chlorine and active hydrogen Effect of Component Molecular Structure and Reaction Phase State on Reaction. The formation reaction of UT and UA has the phenomenon of product catalysis. The reaction mechanism is not only related to the nature of the catalyst, but also to the structure of the reactants and the nature of the solvent. Recent studies on reaction injection molding systems show that phase separation occurs early in the polymerization process and thereafter the reaction turns to diffusion control. The kinetic behavior of UA-producing reactions is more affected by the phase state. The total package reaction kinetics can be summarized as d [U] / dt = A0 [AH] m [NCO] · exp (-Ea / RT). In the formula, the former factor A0 is related to the reaction conditions, and the activation energy Ea is related to the structure of the reactants. [NCO] is the concentration of isocyanate, [AH] is the concentration of active H species such as hydroxyl or NH2 groups, and m is the number of AH-related reaction stages. Response to UT, m = 0.5 ~ 1. The reaction of UA, m = 1 ~ 2, m closer to 2, the greater the catalytic effect of the product.