GB927935A - - Google Patents

Abstract

A catalyst promoter-inhibitor system by use of which solutions of unsaturated polyester resins in copolymerizable monomer solvents can be partially polymerized to a cold-shapable homogeneous mass capable of being stored until subsequently set by heat and pressure comprises benzoyl peroxide as the catalyst, stannous chloride as the promoter and 4-methyl 2, 6 di-t-butylphenol as the inhibitor. The unsaturated polyester resin may be prepared by the polycondensation of at least one acid or anhydride from maleic, fumaric, phthalic, endomethylenetetrahydrophthalic, tetrachloro- or fluoro-phthalic, hexachloro- or fluoro-endomethylenetetra-hydrophthalic, chloromaleic, adipic, sebacic and succinic with at least one polyol from ethylene, diethylene, propylene and polypropylene glycols, glycerol, the butanediols and trimethylol-propane, at least one reactant being unsaturated. Specified comonomers are styrene, methyl-styrene, acrylonitrile, methyl acrylate and methacrylate, vinyl acetate and the allyl esters of phthalic, adipic, maleic, malonic, cyanuric and pyromellitic acids. Mixtures of different polyesters and comonomers may be used and partial polymer gels of different combinations may be blended prior to the final cure. A comminuted filler and/or fibrous reinforcing material may be incorporated in either the solution or the partially polymerized gel. Comminuted fillers specified are carbonates, phosphates, silica, silicates, micromica, dolomite, silicon carbide, asbestos, glass, sandstone, graphite, polyolefines, polyvinyl chloride, carbon black, acetylene black, polyacrylate, polymethacrylates, polyacrylonitrile, polyvinylacetate, polyphthalates, polystyrene, polyurethane, phenol- and urea-formaldehyde resins, polyformaldehyde resin and polyamide resin. Fibrous reinforcements specified are fibres of glass, polyamide, polyolefine, polyester, cellulose acetate, flax, hemp, raffia, sisal, cotton and ramie. Other materials incorporated in the compositions used in the specific examples are zinc stearate, titanium oxide, cadmium sulphide, phenyl salicylate, antimony oxide, phthalocyanine blue, mother-of-pearl, molybdenum sulphide and iron powder. In one embodiment of the invention fire-resistant products are obtained by adding chlorinated paraffins, polyvinyl chloride or antimony oxide to the compositions or by incorporating halogenated acids or esters of boric and/or phosphoric acid in the polyester. In another embodiment porous products are obtained by incorporating a foaming agent which expands at a temperature at which the partially polymerized polyester has sufficient fluidity to permit bubble formation but is sufficiently viscous to retain the bubble formed. Foaming agents specified are azobutyronitrile dinitrosopentamethylenetetramine 4-41 oxy (bis) (benzenesulphonyl-hydrazide) and diazoaminobenzene. Numerous applications, including specific articles which can be made from the compositions, are mentioned.ALSO:A catalyst promoter-inhibitor system by use of which solutions of unsaturated polyester resins in copolymerisable monomer solvents can be partially polymerised to a cold-shapable homogeneous mass capable of being stored until subsequently set by heat and pressure (to give products which may be porous) comprises benzoyl peroxide as the catalyst, stannous chloride as the promoter and 4-methyl 2, 6 di-t-butylphenol as the inhibitor. The unsaturated polyester resin may be prepared by the polycondensation of at least one acid or anhydride from maleic, fumaric, phthalic, endomethylenetetrahydrophthalic, tetrachloroor fluoro-phthalic, hexachloro or fluoroendomethylenettetrahydrochlhalic, chloromaleic, adipic, sebacic and succinic with at least one polyol from ethylene, diethylene propylene and polypropylene glycols, glycerol, the butanediols and trimethylolpropane, at least one reactant being unsaturated. Specified comonomers are styrene, methylstyrene, acrylonitrile, methyl acrylate and methacrylate, vinyl acetate and the allyl esters of phthalic, adipic, maleic, malonic, cyanuric and pyromellitic acids. Mixtures of different polyesters and comonomers may be used and partial polymer gels of different combinations may be blended prior to the final cure. A comminuted filler and/or fibrous reinforcing material may be incorporated in either the solution or the partially polymerised gel. Comminuted fillers specified are carbonates, phosphates, silica, silicates, micromica, dolomite, silicon carbide, asbestos, glass, sandstone, graphite, polyolefines, polyvinyl chloride, carbon black, acetylene black, polyacrylates, polymethacrylates, polyacrylonitrile, polyvinylacetate, polyphthalates, polystyrene, polyurethane, phenol- and ureaformaldheyde resins, polyformaldehyde resin and polyamide resin. Fibrous reinforcements specified are fibres of glass, polyamide, polyolefine, polyester, cellulose acetate, flax, hemp, raffia, sisal, cotton and ramie. Other materials incorporated in the compositions used in the specific examples are zinc stearate, titanium oxide, cadmium sulphide, phenyl salicylate, antimony oxide, phthalocyanine blue, mother-of-pearl, molybdenum sulphide and iron powder. In one embodiment of the invention fire-resistant products are obtained by adding chlorinated paraffins, polyvinyl chloride or antimony oxide to the compositions or by incorporating halogenated acids or esters of boric and/or phosphoric acid in the polyester. In another embodiment porous products are obtained by incorporating a foaming agent which expands at a temperature at which the partially polymerised polyester has sufficient fluidity to permit bubble formation but is sufficiently viscous to retain the bubble formed. Foaming agents specified are azobutyronitrile dinitrosopentamethylenetetraamine 4-41 oxy (bis) (benzene-sulphonylhydrozide) and diazoaminobenzene. Numerous applications, including specific articles which can be made from the compositions, are mentioned.