1359361 Polymerization using electric fields AGENCE NATIONALE DE VALORISATION DE LA RECHERCHE 2 July 1971 [3 July 1970] 31147/71 Headings C3P and C3R A method of polymerization comprises subjecting a liquid comprising one or more monomers to be polymerized, previously freed from traces of impurities tending to inhibit the polymerization, to the polymerizing action of a non-uniform electrical field of maximum intensity greater than 10<SP>5</SP> volts/cm established between electrodes dipping into the liquid. At least one of the electrodes may have a surface or projecting portion which is directed towards the other electrode and has a principal radius of curvature sufficiently small, e.g. less than 10 micrometres, to enable the establishment of the electrical field by means of a potential difference between the electrodes of between 1 and 100 kilo volts. The electrode may have a point or sharp edge or be consituted by a conductor wire or a metallic surface having asperities obtained by treatment with an abrasive. The other electrode may have a flat, cylindrical or spherical surface or be in the shape of a ring or grid. The liquid may be neat monomer or a solution of monomer in a solvent. In the examples pure styrene and pure methyl methacrylate are polymerized using in Example 3 a tungsten point, a razor blade, a brass plate which had been treated with abrasive and a polished brass disc as electrodes. Vinyl chloride and methyl methacrylate may be polymerized alone or dissolved in benzene or tetrahydrofurane. Tetrahydrofurane may also be polymerized by using the electrode with a projecting portion connected to the positive terminal.