Anionic Polymerization of Ethylene Oxide by Anhydrous Potassium Hydroxide

The heterogeneous anionic polymerization of ethylene oxide in tetrahydro-furan by anhydrous potassium hydroxide, prepared in situ by addition of an equivalent of water to potassium naphthalene, was studied. The effect of time of polymerization, degree of conversion, and monomer and catalyst concentration on the molecular weights was studied. The system was a living one with no chain transfer. The efficiency of the catalyst was low. The polymerization was faster than those previously reported using solid potassium hydroxide due to the high dispersion of the catalyst prepared in this manner. The rate of polymerization increased about threefold by addition of two equivalents of dimethylsulfoxide to the catalyst due to solvation effects.