水介质中的天然胶乳氯化反应动力学

Chlorination Reaction Kinetics of Natural Rubber Latex in Aqueous Medium

研究水介质中胶乳氯化反应历程,根据氯化反应的两个阶段分别建立了动力学方程,对水介质中天然橡胶乳氯化反应的进行程度用氯含量分析法进行跟踪。结果表明,两个阶段的反应均为一级反应,第二阶段反应活化能Ea为1 122.468 24 J/mol,指前因子为0.202 3 h^(-1)。提出第二阶段光氯化反应机理,推导的反应速率方程与经验速率方程一致。

It was suggested that chlorination reaction of natural rubber latex in aqueous medium was composed of two stages under different conditions. The substitution, cyclization and addition reaction mainly occurred at room temperature in the first stage and the photo catalytic substitution reaction took place at elevated temperature in the second stage. Reaction dynamic equations of the two stages were obtained and the experiemental results showed that the reaction order was first-order under 293.15, 343.15, 353.15 and 363.15 K. The activation energy was 1. 122 5 kJ/mol and the pre-exponential factor was 0. 202 3 h^-1 in the second stage. Photo-chlorination reaction mechanism of the second stage was also presented and it was consistent with the empirical equation.