Patent GB-994907-A (GB)
Title: Coating compositions
IPC: C08L13/00
Filed: 1962-07-05
Abstract: A coating composition comprises: (1) a polymer or copolymer of a conjugated diolefin of molecular weight 500 to 8000, the (co)polymer having at least 25% of the units derived from the diolefin in the 1,4 configuration; (2) a cyclic anhydride of an ethylenically unsaturated dicarboxylic acid; and (3) a polyepoxide, wherein the cyclic unsaturated anhydride is present in the form of a reaction product with the (co)polymer or in the form of a physical admixture. Specified (co)polymers are polybutadiene, polyisoprene, butadiene-mesityl oxide, butadiene-limonene, isoprene-mesityl oxide, or isoprene-limonene, while maleic anhydride is the preferred cyclic anhydride although tetrahydrophthalic, itaconic, citraconic, aconitic, dimethyl maleic, dialkyl maleic, chloromaleic, and chloroglutaconic or hydroxyglutaconic anhydrides are listed.  A long list of polyepoxides, includes butadiene dioxide, 1,3-bis[2,3-epoxypropoxy) benzene, diphenyldimethyl methane, 1,2,3,4 - tetra(2 - hydroxy - 3,4 - epoxy - butoxy)-butane, the glycidyl polyethers of polyhydric phenols obtained by reacting a polyhydric phenol with a great excess e.g. 4 to 10 mol. excess of a halogen-containing epoxide in an alkaline medium, e.g. bis-phenol-A with epichlorohydric (polyether A), 3,4-epoxycyclohexylmethyl - 3,4 - epoxycyclohexane - carboxylate, the polyglycidyl ether of tetraphenols, e.g. the polyglycidyl ether of 1,1,2,2-tetra-cis-(hydroxy-phenyl)-ethane, the reaction product of catechol and bis(2,3-epoxypropyl)ether, polymers and copolymers of epoxy-containing monomers having at least one polymerizable ethylenic linkage, e.g. poly(allyl 2,3-epoxypropyl ether), poly - (4 - glycidyloxy - styrene), and the condensation product of dimer or trimer acids obtained by polymerizing unsaturated fatty acids such as soyabean oil fatty acids with diepoxides.  Solvents, curing agents for the polyepoxides, driers, fillers and pigments may also be present.  In examples, the polymer is butadienemesityl oxide, the cyclic anhydride maleic anhydride and the polyepoxide (VII, XII, XIII) and (XVI) the reaction product of 2,2-bis(4-hydroxyphenol)propane and epichlorohydrin, (VIII, IX and X) polyether A, (X) the liquid concentrate of the diglycidyl ether of bis-phenol A, (XIV) 3,4 - epoxy - 6 - methyl - cyclohexyl-methyl - 3,4 - epoxy - 6 - methyl - cyclohexane carboxylate, (XV) the concentrate of diglycidyl ether of p,p1-bisphenol A, (XVII) the polyglycidyl ether of 1,1,2,2-tetrakis (hydroxyphenyl) ethane and (XVIII) the polyglycidyl ether of the acid catalysed phenol-formaldehyde condensation product.ALSO:Metal surfaces are provided with baked primer coatings of a composition of (1) a polymer or copolymer of a conjugated diolefin of molecular weight 500-8,000 the (co)polymer having at least 25% of the units derived from the diolefin in the 1,4 configuration (2) a cyclic anhydride of an ethylenically unsaturated dicarboxylic acid and (3) a polyepoxide wherein the cyclic unsaturated anhydride is present in the form of a reaction product with the (co)polymer is in the form of a physical admisture. Specified (co)polymers are polybutadiene, polyisoprene, butadienemesetyl amide isoprenemesetyl oxide, butadiene-limonene and isoprene limonene, while the preferred anhydride is maleic anhydride.  A long list of polyepoxides is given (see Division C3). The compositions may also contain solvents, curing agents for the polyepoxides, driers, pigments and fillers.  The coatings may be applied by spraying brushing or doctoring and may be baked or flame cured.  The metal surface may be coated with a film of the composition and then baked after which a baked film of a different coating material may be applied. The compositions are of particular utility as can liners or as coatings for pipes.