Biodegradability enhanced terpolymer of propylene oxide and ethylene oxide with carbon dioxide using zinc glutarate as catalyst

As an on-going project to synthesise the copolymers of epoxides with carbon dioxide, the ternary polymerisation of propylene oxide and ethylene oxide with carbon dioxide was investigated using an anaerobic system. The terpolymerisation of propylene oxide and ethylene oxide with carbon dioxide was carried out with supported zinc glutarate catalyst, consequently producing high molecular weight poly(propylene-ethylene carbonate) (PPEC). The structure and properties of PPEC were studied by means of gel permeation chromatographic (GPC) analysis, Fourier Transform infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopy, different scanning calorimetry (DSC), and thermogravimetric analysis (TGA) techniques. NMR and FTIR results showed that the terpolymer PPEC was a polycarbonate consisting of propylene carbonate and ethylene carbonate together with random ether linkages. The glass transition temperature (Tg) of the terpolymers decreased with increasing ethylene oxide (EO) content. TGA analysis indicated high thermal stability for the synthesised terpolymer.