Patent GB-963604-A (GB)
Title: Vinyl coating compositions
Inventor: DAVIS JOHN NORMAN SHEARWOOD
IPC: C08F259/04
Filed: 1962-01-01
Abstract: Compositions comprising a thermoplastic paste-forming polymer of vinyl chloride, an epoxy resin, a hardener for the epoxy resin and a monoethylenically unsaturated ester or partial polymer thereof are characterised by the presence of a polymeric material containing free carboxylic acid or carboxylic acid anhydride groups.  The compositions preferably contain an after-chlorinated polyvinyl chloride.  Preferred epoxy resins are halogen-free condensation products of an epihalogenhydrin or dihalogen hydrin and a polyhydric compound, particularly a polyhydric phenol, e.g. condensation products of epichlorhydrin or dichlorhydrin with diphenylolpropane; and epoxidised linseed oil.  Specified hardeners are phthalic anhydride, maleic anhydride and Diels-Alder adducts thereof, caustic soda, calcium oxide, sodium amide, guanidine, diphenyl guanidine, piperidine, triethanolamine, piperazine, hexamethylene tetramine, hydrazodicarbonimide, cyanamide, dicyanamide, melamine, and agents which are also cross-linking agents for the vinyl chloride polymer, e.g. triethylene tetramine, tetraethylene pentamine, pentaethylene hexamine and N-(2-hydroxypropyl)-triethylene tetramine. The unsaturated ester may be an ester of acrylic or methacrylic acid with butanol, pentanols, hexanols, heptanols, octanols or nonanols, or esters of 1-vinyl cyclohexane-3, 4-diol.  The carboxyl containing polymer may be a polymer of acrylic, methacrylic, b -chloracrylic, maleic, fumaric, itaconic, aconitic or crotanic acid, maleic anhydride or a partial ester of a polycarboxylic acid, e.g. monoethyl maleate, or copolymer thereof, e.g. with ethylene, styrene or with vinyl chloride when the acidic polymer may function as paste-forming polymer.  The after-chlorinated polymer may be polyvinyl chloride or a copolymer of vinyl chloride with vinyl acetate, methyl methacrylate, styrene, acrylonitrile, methyl acrylate, ethylene or propylene.  The compositions may comprise conventional plasticisers, e.g. dioctyl phthalates, terephthalates or isophthalates, tricresyl phosphates, adipates and sebacates; diluents, e.g. white spirit, xylene or hydroxyethyl butyl ether; and fillers, pigments and stabilizers.  The compositions may be used for coating metals, fabrics, glass fibres, ceramics and thermoplastic films, for bonding metals and for floor-coverings. An example describes a composition comprising a vinyl chloride polymer, a copolymer of vinyl chloride, vinyl acetate and maleic anhydride, the diglycidyl ether of diphenylol propane, N-(2-hydroxy-propyl)-triethylene tetramine, 2-ethyl hexyl acrylate, dinonyl phthalate, an organotin stabilizer and white spirit. The acrylate may be replaced by butyl methacrylate or undecyl acrylate, and the glycidyl ether by epoxidised linseed oil.ALSO:Substrates, e.g. of metal, glass or ceramic, may be coated with compositions comprising a thermoplastic paste-forming polymer of vinyl chloride, an epoxy resin, a hardener for the epoxy resin and a monoethylenically unsaturated ester or partial polymer thereof and characterized by the presence of a polymeric material containing free carboxylic acid or carboxylic acid anhydride groups.  Specified metal substrates are iron, steel, zinc and aluminium, and the compositions may be applied by spraying, painting, doctor knife coating, roller coating, centrifugal casting or curtain coating.  Specified epoxy resins are condensates of epichlorhydrin and diphenylolpropane, and epoxidized linseed oil.  Specified hardeners are dicarboxylic acid anhydrides, organic and inorganic bases, hydrazodicarbonimide, cyanamide, dicyanamide melamine and agents which are also crosslinking agents for the vinyl chloride polymer, e.g. polyalkylene polyamines.  The unsaturated ester may be an acrylic or methacrylic ester of C4-9 alkanols, or an ester of 1-vinyl cyclohexane-3,4-diol. The carboxyl containing polymer may be an ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, vinyl chloride-vinyl acetate-maleic anhydride terpolymer or polyacrylic acid.  The compositions may also contain an after-chlorinated polyvinyl chloride or copolymer of vinyl chloride with vinyl acetate, styrene, ethylene, propylene, methyl acrylate, methyl methacrylate or acrylonitrile; plasticizers, e.g. dioctyl phthalates, tricresyl phosphate, adipates and sebacates; diluents, e.g. white spirit, xylene and hydroxyethyl butyl ether; fillers; pigments and stabilizers.  An example describes the coating of shot-blasted mild steel with a composition comprising a vinyl chloride polymer, a copolymer of vinyl chloride, vinyl acetate and maleic anhydride, the diglycidyl ether of diphenylolpropane, N-(2-hydroxypropyl)-triethylene tetramine, 2-ethyl hexyl acrylate, dinonyl phthalate, an organo tin stabilizer and white spirit, and the curing of the coating at elevated temperature. Similar coatings are obtained when the acrylate is replaced by butyl methacrylate or undecyl acrylate, and the glycidyl ether by epoxidized linseed oil.