Patent GB-961193-A (GB)
Title: Unsaturated polyester resins and a method of preparing same
IPC: C08G63/682
Filed: 1960-08-23
Abstract: Unsaturated polyester resins derived from unsaturated polycarboxylic acids and polyhydric alcohols, one of the unsaturated acids having the formula: <FORM:0961193/C3/1> wherein X and Y are H, C1-3 alkyl or halogen, are stabilized after polyesterification with a polymerization inhibitor, dissolved in a copolymerisable liquid monomer and cured.  The specified acid may be introduced as such, as an ester which undergoes ester interchange in the polyesterification, or by Diels-Alder reaction from a dicarboxylic acid: <FORM:0961193/C3/2> and chloroprene.  Specified other possible components of the polyester are: maleic, fumaric, citraconic, pyrocinchonic, mesaconic, itaconic, acrylic, methacrylic, phthalic, isophthalic, terephthalic, tetrachlorophthalic, hexachloroendomethylenetetrahydrophthalic, endomethylenetetrahydrophthalic, adipic and sebacic acids and ethylene, di- and tri-ethylene, propylene and butylene glycols, 1, 6-hexane diol, 2, 2-bis-(4-hydroxyphenyl) propane, 2-butane-1, 4-diol aminoalcohols, glycerol,  trimethylolpropane, pentaerythritol and cyclohexanol. Polymerization inhibitors specified are hydroquinone, quinones, amines and nitro-  and nitroso-compounds. Specified comonomers are styrene, vinyltoluenes, vinylxylenes, vinyl acetate, esters and nitriles of acrylic and methacrylic acids, esters and ethers of allyl, methallyl and chloroallyl alcohols, and triallyl cyanurate, phosphonate and borate. Specified curing agents are dibenzoyl, acetylbenzoyl and MEK peroxides, cumene and cyclohexanone hydroperoxides, azobisisobutyronitrile, redox-activators such as sulphonic acids and amines, cobalt, lead and manganese naphthenates and Friedel-Crafts catalysts such as BF3.  Compositions.  The unsaturated polyester resins of the invention may be compounded with other synthetic resins which may be incorporated during the preparation of the polyester resins or subsequently, e.g. epoxide resins, polyvinylacetals, phenolic, urea-, melamine-, dicyandiamide-, caseine-, polyamide-, amino-amide-, sulphonamide, aniline-, furane-, cyclohexanone- and silicone-resins, saturated and other un-saturated polyesters, polyvinyl chloride, acetate and ethers, polyvinylidene chloride and polyacrylates and methacrylates.  Elastomers may also be incorporated e.g. India rubber, chlorinated rubber, rubber hydrochloride and synthetic rubbers such as polybutadiene, copolymers of butadiene with styrene or acrylonitrile, polyisobutylene, polyisoprene, polychloroprene and polyethylene sulphide Other optional ingredients are light stabilizers, e.g. 2, 4-dihydroxy or 2-hydroxy-4-methoxy benzophenone; heat stabilizers e.g. glycidyl ethers and esters (several are specified), epoxidised vegetable drying oils and esters of their fatty acids or calcium, barium, lead, zinc or cadmium salts of such acids, salts of organic acids, amines and organo-metallic compounds; fillers, e.g. glass fibres, asbestos, porcelain, siliceous and glass powders, chalk, talc and kaolin; pigments and organic dyestuffs.  Epoxidation.  A proportion of the double bonds of the polyester may be epoxidised enhancing stability and miscibility with other synthetic resins.  The epoxide groups may also take part in the curing.  In Example 15 40% of the double bonds of the polyester are epoxidised and in 80 p.b.w. of a styrene solution of the partially epoxidised polyester are dissolved 20 p.b.w. of an epoxide resin obtained by alkaline condensation of 1 mole 2,2-bis-(4-hydroxyphenyl) propane with 2 moles epichlorhydrin prior to curing at 100 to 120 DEG C. with 1 p.b.w. acetylbenzoyl peroxide and 0.5 p.b.w. BF3triethylamine adduct.