GB1181502A - Polymerising by Electrical Discharge. - Google Patents

Abstract

1,181,502. Polymerizing by electric discharge. RADIATION RESEARCH CORP. 1 March, 1967 [2 March, 1966], No. 9082/66. Heading C3P. [Also in Division H1] In a process of polymerizing a material in which ionized or otherwise excited species are produced by electrical discharge in a gaseous atmosphere and are caused to bombard a liquid comprising the said material, which is thereby polymerized, a fresh thin film of the liquid is continually presented for bombardment on a carrier surface. In one form of apparatus a cylindrical electrode 13 is partially immersed in liquid 14 at the bottom of a container 10 provided with a vacuum connection 11 and a gas inlet 12, and is rotated by magnets 15 and 16 to present a continuous film of liquid to ions attracted by an accelerating grid 20 from a discharge established in a neckportion 22 of the container by a microwave head 21 connected to a generator 23. The electrode 13 is connected to the grid 20 which, together with a further grid 24, is connected across a D.C. source 25, the polarity of which determines the polarity of the ions attracted from the discharge. In an alternative embodiment (Fig, 1, not shown) an A.C. discharge is established directly between the electrode 13 and a nearby arcuate electrode. In a further embodiment, the electrodes are two flat plates. Examples describe the polymerization of styrene, isobutylene and acrylonitrile, with the optional use of a vinylidene chloride sensitizer. The discharge occurs in a gas or vapour of the material being polymerized, which gas or vapour is kept at a pressure of, e.g., 3 or 0À1 mm. Hg by application of a vacuum pump and controlled admission of argon. The discharge may be initiated by microwaves, as in the arrangement shown, or by U.V. light or other ionizing radiation.