| 摘要 |
A normally liquid or normally solid vinyl monomer is polymerized by irradiating the monomer in the presence of water with radiation of a wavelength ranging from 10-1 to 10-10 c.m, using a catalytic amount of a catalyst comprising a mixture of an insoluble silver halide and a silver salt more water soluble than the silver halide, which silver salt does not possess an anion which is a halogen acceptor and is not an active oxidizing agent. The radiation may be visible or ultra-violet light, X-rays or gamma rays. The silver halide may be silver bromide, chloride or iodide, and the silver salt may be silver acetate, benzoate, citrate, fluoride, lactate, laurate, phenol-sulphonate, nitrate, picrate, selenate, oxalate, salicylate, sulphonate, sulphate or tartrate. The catalytic activity of the mixture of silver compounds may be promoted by means of zinc oxide, zirconium dioxide, titanium dioxide or silicon dioxide or of an optical sensitizing dye such as erythrosin, eosin, pinacyanol, or 1,11-diethyl-2,21-cyanineiodide. The monomer may be acrylamide, acrylonitrile, N-ethanol acrylamide, methacrylamide, methacrylic acid, acrylic acid, calcium acrylate, vinyl acetate, methyl methacrylate, methyl acrylate, ethyl acrylate, vinyl benzoate, vinyl pyrrolidone, vinyl methyl, butyl, isopropyl, or isobutyl ether, vinyl butyrate, butadiene or mixtures of ethyl acrylate with vinyl acetate, acrylonitrile with styrene or butadiene with acrylonitrile. There may also be present a small amount of a cross-linking agent such as N,N1-methylene-bis-acrylamide, triallyl cyanurate, divinyl benzene, divinyl ketones and diglycol-diacrylate. Polymerization may be effected in bulk or aqueous dispersion, and the process may be carried out in a continuous flow.
|
