水溶性封闭异氰酸酯单体的解封动力学

采用热失重分析(TGA)法研究了水溶性封闭型异佛尔酮二异氰酸酯(IPDI)的热分解过程, 利用傅里叶变换红外光谱法(FTIR)考察了谱图中40 与140 ℃两种温度下的异氰酸酯特征峰. TGA与FTIR的结果表明失重阶段即对应封闭异氰酸酯的解封闭反应. 用Friedman-Reich-Levi (FRL)和Flynn-Wall-Ozawa (FWO)两种动力学模型研究了解封反应的表观活化能E, 所得平均表观活化能分别为125.0和124.5 kJ·mol-1. 采用双等双步法对解封过程进行表观机理函数判断, 结果符合Jander方程, 反应机理为三维扩散, 结合FWO方程确定了反应级数n和指前因子对数lnA的范围.

Deblocking Kinetics of Water-Solubility Blocked Isophorone Diisocyanate

The thermal decomposition process of water-solublity blocked isophorone diisocyanate (IPDI) was studied using thermal gravimetric analysis (TGA). The characteristic peaks of isocyanante groups at 40 and 140℃ were observed by Fourier transform infrared spectroscopy (FTIR). Results from TGA and FTIR showed that the degradation stage was a deblocking reaction of the blocked adduct The Friedman-Reich-Levi (FRL) and Flynn-Wall-Ozawa (FWO) models were employed to investigate the apparent activation energies which were 125.0 and 124.5 kJ·mol~(-1), respectively. Based on the double equal-double step method, the reaction was analyzed by the apparent mechanism of the process of deblocking according to the Jander equation, which indicated that the reactive mechanism was a three-dimensional diffusion. The reaction order (n) and the logarithm of pre-exponential factor (lnA) were also determined using the FWO equation.