己二酸/乙二醇体系自催化缩聚反应的动力学研究

Kinetics of Self-catalyzed Polyesterification of Adipic Acid/glycol System

在对饱和二元酸与二元醇的缩聚反应研究中发现,由于体系中不断有水的排除,所以体系并非是一个恒容体系,体系的密度也是在不断变化的,而以往的研究中却忽视了这一点。Hu-Wang[1]等人虽然对缩合水的排除进行了校正,但是用质量摩尔浓度来计算体系的酸浓度。以己二酸与最简单的二元醇乙二醇为例,考虑水的排除以及密度的变化对缩聚反应动力学的影响,认为用体积摩尔浓度更为科学,推导出以体积摩尔浓度来表示酸浓度的总包动力学方程,计算出该体系的反应速率常数和活化能,并与以质量摩尔浓度表示的酸浓度所得出的动力学参数进行了比较。

In an investigation on the kinetics of the reaction between adipic acid and glycol, it has been found that based on the perpetual removal of water, the system is really not an invariable volume, and the systematic density is also corresponding to change, but pre - experiment could not calculate it. Hu - Wang etc had revised the data which contained the removal of condensation water, but just based on the molar concentration to calculate the systematic acid concentration. In the article, taking adipic acid and glycol to investigate, and considering the factors of removal water and density change, a general rate equation is derived by expressing the acid concentration with the volume concentration mol/L, the rate constants and the activation energy are calculated , and compared to the kinetics parameter by expressing the acid concentration with the molar concentration mol/L.