A method for surface modification of surfaces of plastic compounds

摘要

The susceptibility to adhesion of vulcanizable compositions of a copolymer of ethylene and propylene is improved by coating the composition with a vulcanizable natural or synthetic rubber, and subsequently vulcanizing the copolymer of ethylene and propylene and the coating polymer. The composition to be applied to the surface of the copolymer may be in the form of a solution in an organic solvent. Solvents exemplified are chlorinated hydrocarbons e.g. trichloroethylene, and naphtha and acetone. Curing may be effected by heating to 100 DEG C to 250 DEG C in the presence of an organic peroxide and sulphur. The vulcanising agent may be present in amount 2-6% by weight based on the polymer to be cured. A third comonomer may be present in the ethylene/propylene copolymer, which may be butadiene, hexadiene- 1, 4 or dicyclopentadiene. This monomer will confer unsaturation on the copolymer. The copolymer may be in the form of a foam. The composition may contain a blowing agent so that foaming and vulcanisation occur simultaneously. The blowing agent may be benzene sulphonyl hydrazide. The rubber blends may also contain a copolymer of ethylene and propylene and of ethylene with vinyl acetate. The coated substrate may be adhered to a metal, e.g. steel, wood, textile fabric or leather, which may first be painted if desired. Specified adhesives comprise polychloroprene and a phenolic resin.