Homopolymerization and copolymerization of cyclohexene oxide with carbon dioxide using zinc and aluminum catalysts

Homopolymerization of cyclohexene oxide and copolymerization of cyclohexene oxide and carbon dioxide using zinc and aluminum catalysts having the same type of substitution were studied. The aluminum derivatives are more active, in both homopolymerization and copolymerization of cyclohexene oxide and carbon dioxide. From Al-27 NMR spectra it was observed that aluminum catalysts consist of both penta- and hexacoordinated species but after reaction with monomer predominantly become pentacoordinated. During initiation the equilibrium between five and six hypercoordinated species is shifted toward lower coordination. The nature of the catalysts and their symmetry influence the yield in the copolymerization of CHO and CO2 and the amount of carbon dioxide inserted. The yield obtained with aluminum derivatives luring the copolymerization of CHO and CO2 ranged between 41.2 and 93.6% (149.85-340.4 g of polymer/g of metal).