GB1016077A - Unsaturated polyester resins - Google Patents

Abstract

Air-drying unsaturated polyesters are made by heating together (a) 1 mol. of maleic acid and/or maleic anhydride and/or fumaric acid; (b) 0.9-1.05 mols. of diethylene glycol; and (c) 0.1-0.85 mols. of dicyclopentadiene of 85-100% purity. Up to 50 mol. per cent of (a) may be replaced by a saturated dicarboxylic acid (e.g. adipic, phthalic or isophthalic) and up to 50 mol. per cent of the diethylene glycol may be replaced by another glycol containing 2-6 carbon atoms (e.g. ethylene glycol, propylene glycol or dipropylene glycol). The dicyclopentadiene may contain some methylcyclopentadiene. At the end of the esterification, an inhibitor (e.g. p-quinone) and, possibly, an inhibitor-accelerator (e.g. acetamidine hydrochloride and propylene glycol) may be added. Coating compositions are made by dissolving the polyester in a solvent and/or a copolymerizable monomer. Suitable solvents are aromatic hydrocarbons, ketones, esters and mixtures of aromatic hydrocarbons and alcohols. Suitable monomers are styrene, vinyl toluene, diallyl phthalate, diallyl isophthalate, ethylene glycol dimethacrylate, butyl methacrylate and diallyl maleate. The compositions containing monomers are catalysed by adding a peroxide (e.g. M.E.K. peroxide or benzoyl peroxide) and a cobalt salt (e.g. the octoate or naphthenate). The catalyst may be in a nitrocellulose undercoat. Example 5 discloses a paint comprising the unsaturated polyester, p-quinone, diallyl phthalate, xylene, ethylene glycol monobutyl ether, titanium dioxide, cobalt octoate and benzoyl peroxide. Example 11 disclosed a wood filler comprising the unsaturated polyester, ethylene glycol monomethyl ether acetate, silica gel aerosol, asbestine, burnt umber, bone black, Van Dyke brown, raw sienna, burnt sienna, carbon black, cobalt octoate and zirconium naphthenate. Example 12 discloses a paint comprising the unsaturated alkyd, a coconut oil modified glyceryl phthalate, xylene, ethyl alcohol, titanium dioxide, magnesium silicate, calcium carbonate, clay, silica gel aerosol, cobalt octoate, methyl ethyl ketoxime and, possibly, diallyl phthalate and M.E.K. peroxide. Coating composition may be made by dissolving a mixture of nitrocellulose and a resin derived from maleic anhydride, diethylene glycol and dicyclopentadiene in methyl ethyl ketone. Reference has been directed by the Comptroller to Specification 937,980.ALSO:Unsaturated polyester based coating compositions for application to wood, "Masonite" (Registered Trade Mark), masonry, stucco, glass, bare or phosphated steel, paper or cloth comprises a solution in an organic solvent and/or an unsaturated monomer of a polyester derived from (a) maleic or fumaric acids (with or without a saturated dicarboxylic acid), (b) diethylene glycol (with or without another glycol), and (c) dicyclopentadiene (with or without methylcyclopentadiene). The solutions may also contain the usual peroxide curing agents, cobalt accelerators, stabilizers, pigments and fillers. They may be applied to the substrate by spraying, brushing, roller coating, curtain coating or film coating. When applied to wood, they may be applied over a nitrocellulose priming coat which contains a peroxide curing agent and when applied to wood, masonry or stucco they may be applied over a polyvinyl acetate emulsion primer. Reference has been directed by the Comptroller to Specification 937,980.