GB914426A - Solvent-resistant flexible polymerisation products on the basis of unsaturated polyester resins - Google Patents

Abstract

A polymerizable mixture comprises (a) 50 to 80 parts by weight of an unsaturated resinous polyester, (b) 50 to 20 parts by weight of a copolymerizable monomer and (c) 5 to 50% by weight of (a)+(b) of a reaction product of (i) maleic, fumaric, itaconic, mesaconic or citraconic acid (or anhydride) with (ii) a hydroxyalkylation product of a tri- or higher polyhydric aliphatic alcohol in such proportions that there is about 1 mol. of (i) per mol. of free hydroxy groups in (ii). Reactants (ii) are obtained by reacting the polyhydric alcohols, e.g. glycerol, trimethylol propane, pentaerythritol or sorbitol, with epoxides, e.g. epoxyethane, epoxypropane, epoxybutane, epichlorhydrin or epoxyethylbenzene. Ingredient (a) is a conventional unsaturated polyester of an unsaturated polycarboxylic acid, optionally in admixture with a saturated acid, and a polyhydric alcohol. Ingredient (b) may be a monomer containing a vinyl, allyl or acryloyl group, e.g. styrene. Polymerization may be effected with free-radical catalysts, e.g. organic peroxides, preferably conjointly with p metal driers. Granular or fibrous fillers may be added, e.g. glass fibre threads or fabrics, and also pigments and dyes. The compositions may be used for lacquer or film coatings, impregnation and producing shaped articles. In examples ingredient (a) is a mixture of polyesters derived from maleic, phthalic and adipic acids and triethylene glycol and from maleic and phthalic acids and propylene and ethylene glycols; (b) is styrene; (c) is the reaction product of (i) maleic anhydride and (ii) the hydroxyalkylation product of glycerol or sorbitol and ethylene oxide; and the catalyst system is methyl ethyl ketone/cobalt naphthenate. Specification 821,988 is referred to.