PM3 Semi-Empirical Method on the Ring Opening Polymerization of ε-Caprolactone Using Bis (Benzoyltrifluoroacetone)Zirconium(IV) Chloride as catalyst

Abstract

Polycaprolactone (PCL) is an interesting polymer because of its biodegradability, good mechanical properties, and the excellent miscibility with a large range of other polymers. PCL can be obtained via ring opening polymerization (ROP) of ε-caprolactone (ε-CL) by using Lewis acid as catalyst. The purpose of this study was to focus on the study of the plausible mechanism of the ROP of ε-CL using bis-(benzoyltrifluoroacetone)zirconium(IV) chloride as a catalyst. In this research, PM3 semi-empirical method was conducted to optimize the polymer and complex structure. After that, HyperChem 8.0 program package was used to calculate and to visualize the geometry structure. This program run on a personal computer with Windows 07 operating system. The results of the computational calculation indicate that, to obtain PCL using bis(benzoyltrifluoroacetone)zirconium (IV) chloride catalyst needed several reaction steps, that is coordination ε-CL on the zirconium complex, deprotonation of ε-CL, the ε-CL insertion, and the chain propagation.