GB1396189A - Fibre-reinforced thermosetting polyester resins - Google Patents

Abstract

1396189 Impregnated fabric laminates IMPERIAL CHEMICAL INDUSTRIES Ltd 16 Nov 1973 [15 Dec 1972] 57974/72 Heading B5N [Also in Division D1] In a fibre-reinforced thermosetting polyester resin composite adhesion between resin and fibres is enhanced by the presence of a copolymer of ethylene and 0À1 to 40% by wt. of the copolymer of one or more ethylenically unsaturated esters of a carboxylic acid and/or one or more ethylenically unsaturated acids wherein the unsaturated esters contain 4 to 7 carbon atoms and the unsaturated acids contain 3 to 5 carbon atoms. A kit of fibres, resin and copolymer is claimed. The thermosetting polyester resin comprises a cross-linked or crosslinkable polycondensate of one or more polyhydric alcohols with one or more polybasic acids or anhydrides where at least one acid, anhydride or alcohol is ethylenically unsaturated. Specified compounds are ethylene glycol, phthalic anhydride, maleic anhydride, methyl, and butyl acrylates and methacrylates, vinyl acetate vinyl toluene and diallyl phthalate. Styrene may be used to cross-link the condensate. Peroxide catalysts and cobalt promoters are listed. The ethylene may be copolymerized with vinyl acetate, acrylic or methacrylic acid or methyl, ethyl or butyl acrylate or methacrylate. The example discloses a terpolymer of 74% ethylene, 13% methacrylic acid and 13% methyl methacrylate. The fibres may be high or low alkali glass, metallic whiskers, carbon, nylon, polyethylene terephthalate, cotton, flax, sisal, jute, asbestos, fibrous tale or zinc or aluminium gauze. The fibres may be in the form of rovings, staple fibres, needled mats, chopped strand mats of woven cloth or metal gauze. Lamination.-A 0À76 mm. thick foil of ethylene copolymer is sandwiched between and chopped strand mats and the mats impregnated with a thermosetting, polyester resin. The resin and foil may be allowed to cross-link without heating or the laminate may be baked at 120‹ C. 12 hours after impregnation. In alternative methods of producing resinfibre composites a film of the ethylene copolymer is melt coated on to the fibrous material; powdered copolymer is sprinkled over the fibrous material and radiant heat is applied to fuse the copolymer; finally powdered copolymer may be dispersed in the uncross-linked thermosetting resin.