| Abstract: | The influence of 12-crown-4, 15-crown-5, 18-crown-6, dicyclohexano-18-crown-6 and dicyclohexano-24-crown-6 on the propylene oxide polymerization with potassium hydride was studied. The highest reaction rate was obtained in the presence of 18-crown-6 or dicyclohexano-18-crown-6. The use of dicyclohexano-18-crown-6 was found to enhance the molecular mass of polymers more than other ligands. The observed effects were related to the heterogeneity of the reaction mixture and the structure of the crown ether complexes with the potassium cation. |
