Cyclopolymerization of diepoxides

Abstract

Abstract The monomer 1,2,5,6‐diepoxyhexane can be polymerized by a variety of catalysts to afford a polymer which has tetrahydropyran recurring units as a result of a cyclopolymerization mechanism. A phosphorus pentafluoride‐water catalyst system gives soluble polymer with inherent viscosities as high as 0.37. The polymerization rates, conversions, and polymer molecular weights are affected both by catalyst to monomer ratio and the amount of water present. A diethylzine‐water catalyst system gives a higher molecular weight polymer with very limited solubility, the soluble portion of which has an inherent viscosity of 0.45. In contrast, 1,2,4,5‐diepoxypentane polymerizes to a completely insoluble polymer in all catalyst systems employed. Samples of poly‐1,2,5,6‐diepoxyhexane prepared with the diethylzine‐water catalyst show a higher degree of crystallinity than those samples prepared with the phosphorus pentafluoride‐water catalyst, as demonstrated by x‐ray patterns and differential thermal analyses.