Copolymerization of carbon dioxide and propylene oxide with highly effective zinc hexacyanocobaltate(III)-based coordination catalyst

Copolymerization of propylene oxide and carbon dioxide was successfully carried out by using double metal cyanide complex (DMC) based on Zn-3[Co(CN)(6)](2). It has been found that this catalyst demonstrated highly enhanced catalytic activity over 1000 g copolymer per gram of Zn-3[Co(CN)(6)](2) compared with its analog based on Zn-3[Fe(CN)(6)](2). The copolymers prepared were characterized by IR, H-1 NMR, the molar fraction of CO2 (F-CO2) for copolymer was as high as 0.31 under optimum condition. Propylene carbonate was also identified as co-product by the spectrometry. The study showed that lower temperature is favorable for incorporation of CO2 into copolymer instead of propylene carbonate, and F-CO2 is significantly influenced by amount of catalyst used. The kind of complexing agent employed in preparation impacted on the catalytic activity, but not yet for F-CO2. (C) 2004 Elsevier Ltd. All rights reserved.