Cocatalysts for the linear polymerization of epoxides by dibutylzinc

Abstract

Abstract A study of the nature and quantity of materials that will react with dibutylzinc to act as cocatalysts for the polymerization of phenyl glycidyl ether has led to the finding of several very effective catalyst systems. These cocatalysts may be grouped in the following classifications: ( 1 ) highly effective: water and acetone; ( 2 ) effective: methanol, ethanol, n ‐butanol, and oxygen; ( 3 ) slightly effective: isopropancl, tert ‐butanol, diethylamine, n ‐butyraldehyde, and phenol; and ( 4 ) inhibitors: acetic acid, ethyl acetate, and carbon dioxide. The poly(phenyl glycidyl ether) produced by these catalysts is a high melting (204°C.), high molecular weight crystalline polymer which is insoluble in most common organic solvents. Ethylene oxide and propylene oxide have also been polymerized by the dibutylzinc–water system to high molecular weight polymers in high yield. Epichlorohydrin, on the other hand, gave only low molecular weight oils in low yields, probably due to reaction of the catalyst species with the reactive chlorine of the monomer.