Patent GB-1022270-A (GB)
Title: Improvements in or relating to polyester resins
IPC: C08G63/60
Filed: 1964-02-10
Abstract: A polyester resin is produced by interacting at elevated temperature and in one or more stages (i) a high molecular weight polyester of isophthalic acid and a diol or a copolyester of iso- and terephthalic acid and a diol or a mixture of such polyesters or copolyesters, (ii) a saturated or unsaturated dicarboxylic acid, other than iso- or terephthalic acid or its anhydride or one of its mono- or oligoesters and (iii) (if the ester (ii) is derived from an excess of acid) a polyol.  Polyester (i) may be in the form of chips or granules.  The diol from which it is derived may be ethylene glycol.  At least 2 moles of dicarboxylic acid may be used per 3 moles of polyester and the dicarboxylic acid and polyol may be in equivalent amount. Dicarboxylic acids specified are maleic, fumaric, itaconic, citraconic, mesaconic, 1,4-dihydro-naphthalene-2,3- or 1,2-dicarboxylic acids, succinic, glutaric, adipic, pimelic, suberic azelaic, sebacis, phthalic, hexahydrophthalic, tri- or tetrachlorophthalic acids.  If an unsaturated acid is used it must constitute at least 50 mole per cent of the dicarboxylic acid. The dicarboxylic acid may be replaced by one of its mono- or oligo-esters with any of the diols specified below for (iii) or with methyl, ethyl, n-or iso-propyl, allyl, n-, sec-, tert- or iso-butyl, amyl, hexyl, octyl or benzyl alcohols.  The polyol (iii) may contain 2, 3 or more hydroxyl groups per molecule but the concentration of polyols containing more than 2 groups per molecule should be such that the excess hydroxyl groups (i.e. those in excess of 2 per molecule) do not constitute more than 10% of all the hydroxyl groups.  Diols may boil at above 200 DEG  C. Diols specified are mono-, di-and triethylene glycol, 1,2- and 1,3-propylene glycols, 1,3- and 1,4-butylene glycols, neopentylene glycol, 2-ethyl-2-butyl propylene glycol, 1,4-di(hydroxymethyl) cyclohexane, 1,4-dihydroxybut - 2,3 - ene, Bisphenol - A, di-(hydroxymethyl) benzenes, di(hydroxymethyl) toluenes; addition products of ethylene, propylene or butylene oxides with these or with resorcinol, hydroquinone, bis(4-hydroxyphenyl)-methane or ethane and acetals or ethers derived from alcohols containing more than 2 hydroxyl groups in which 2 free hydroxyl groups remain. The acetal and ether groups may contain up to 10 carbon atoms.  Partially acetalized and etherified glycerol, trimethylolpropane, trimethylolethane, hexane triol and pentaerythritol are specified.  Polyols containing more than 2 hydroxyl groups specified are glycerol, trimethylolethane and propane and hexane triol. Polyesterification may be effected by dissolving the polyester in one monomer reactant and adding the other.  The reaction temperature may be between 180 DEG  C. and the decomposition temperature of the reactants. The pressure may be superatmospheric. An aliphatic, aromatic or terpene, high boiling solvent or diluent may be used.  If a terpene is used in conjunction with an unsaturated acid they may interact.  A resinic acid or a fatty acid of 12-22 carbon atoms may be added together with the second monomeric reactant. An acid having more than 2 carboxyl groups may also be added in such a concentration that the excess carboxyl groups (i.e. those in excess of 2 per molecule) do not constitute more than 20% of all the carboxyl groups.  A quantity of mono-alcohol or carboxylic acid equivalent to the excess acid or hydroxyl groups may be used. Monoacids specified are benzoic and fatty acids of more than 12 carbon atoms.  One mole of a monohydroxymonocarboxylic acid, e.g. rincinoleic or 12-hydroxystearic, may be added per 0.5-5 moles of dicarboxylic acid.  Polyesters of terephthalic acid may be added. The product may have an acid number of up to 70. If the product was derived from an unsaturated dicarboxylic acid it may be dissolved in an olefinically unsaturated monomer and copolymerization effected by adding a catalyst and a cocatalyst.  10-80% of the monomer may be used and monomers containing no conjugated double bonds are preferred.  Monomers specified are: m- and p-vinyltoluene, N-vinyl pyrrolidone, styrene, a -methyl and a -chloro-styrene, vinyl acetate and propionate, allyl acetate and propionate, diallyl maleate, fumarate, succinate, adipate, azelate, sebacate and phthalate, triallyl phosphate and cyanurate, methyl, ethyl, propyl, n-, sec-, tert- or isobutyl, amyl, hexyl octyl or allyl acrylate or methacrylate, diallyl itaconate, vinyl or allyl borate, acrylonitrile or a mixture thereof with up to 10 mole per cent of divinyl benzene. Catalysts specified are peroxides and azocompounds, many are listed. Cocatalysts specified are tertiary amines and heavy metal salts of organic acids.  The products of this reaction may be made into shaped bodies.