Electroinitiated Polymerization of Styrene: I. Electrolysis of Alkali Metal Nitrates in Dimethylformamide Containing Styrene Monomer

Electrolysis of alkali metal salts in dimethylformamide containing styrene monomer produced polymerization. The rate of reaction increased with increase in current and monomer concentration and varied dramatically with choice of initiating salt. The alkali metal nitrates from sodium to cesium produced polymer but lithium was ineffective. KNO3 was the most efficient of the alkali metal salts tested.The effects of inhibitors on the rates of polymerization together with analysis of copolymer composition established that polymerization proceeded by an anionic mechanism.A detailed study with KNO3 solution showed that relatively high electrical efficiencies were attained and that the number-average molecular weights ranged between 2 000 and 5 000.