Copolymerization of cyclohexene oxide with carbon dioxide over nano-sized multi-metal cyanide catalysts

The copolymerizations of carbon dioxide (CO2) and cyclohexene oxide (CHO) using nano-sized double and multi-metal cyanide catalysts were investigated. The nano-sized double metal cyanide (NDMC) catalyst was prepared by reacting K3[Co(CN)6]2 and ZnCl2 in a reverse emulsion condition and nano-sized multi-metal cyanide (NMMC) catalyst by reacting K3[Co(CN)6]2, K4Fe(CN)6, YCl3 and ZnCl2 at the similar conditions. Neutral surfactant, Igepal CA-520, used in the preparation step played important roles in acting both as an emulsifier and as a complexing reagent. NDMC and NMMC catalysts were demonstrated to be highly effective for copolymerizations of CHO with CO2. The catalysts showed catalytic activity as high as 41.6 g/mol of Zn per hour at 80 °C and the carbonate content in the copolymer was estimated to be 57.8%. Effects of reaction conditions such as reaction time, temperature, CO2 pressure and catalyst concentration on copolymerizations were investigated.