비스(2-히드록시에틸)테레프탈레이트의 중축합 반응 속도에 관한 연구

The Kinetics of Polycondensation of Bis(2-Hydroxyethyl) Terephthalate in an Open System

The polycondensation of bis (2-hydroxyethyl) terephthalate has been kinetically investigated in the presence of zinc acetate as a catalyst at 26$0^{\circ}C$ and 27$0^{\circ}C$. On the basis of the titrated results of carboxyl end groups, a thermal degradation reaction of chain scission was assumed to occur simultaneously with the polycondensation reaction a certain propagation reaction period later. If kp and kd are the rate constants of propagation and degradation reactions, respectively, and t is the reaction time, the following relations were finally obtained for the number-average degree of polymerization, where tc is initiation time of chain scission reaction and a is a constant, $\leq$1. The equations were found to be in good agreement with the experimental results.