GB806730A - Improvements in the production of unsaturated polyester resins and of copolymers therefrom - Google Patents

Abstract

An unsaturated polyester resin is the polycondensation product of (a) an alpha-unsaturated polycarboxylic acid, (b) a polyhydric alcohol, and (c) at least 30 per cent with reference to the total weight of the reactable materials of a reaction product of colophony or abietic acid and an alpha-ethylenically unsaturated monocarboxylic acid (e.g. acrylic or chloracrylic acid). Specified unsaturated polycarboxylic acids are maleic, fumaric, itaconic, aconitic, citraconic, monochloromaleic and dichloromaleic acids. Specified polyhydric alcohols are ethylene, 1 : 2 - propylene, 1 : 3 - propylene, 1 : 4-butylene, 1 : 5-pentylene, 1 : 6-hexylene, diethylene, triethylene and tetraethylene glycols; also 2 : 2-dimethylpropanediol-1 : 3, 1 : 4-butene diol, 1 : 2-butene diol, glycerine, butanetriol, trimethylol propane, pentaerythritol, terephthalic alcohol or halogensubstituted derivatives thereof. Part of the unsaturated polycarboxylic acid may be replaced by a saturated polycarboxylic acid (e.g. phthalic, terephthalic, phenylene dibutyric, succinic, glutaric, alpha-methylglutaric, adipic, oxadibutyric, sulphonyl dibutyric or tetrachlorophthalic acid) or by a saturated or unsaturated hydroxyacid. Part of the polyhydric alcohol may be replaced by an amino alcohol (e.g. ethanolamine). Polycondensation may be effected by reacting together all the components simultaneously or by reacting a known unsaturated polyester resin (e.g. from maleic acid, phthalic acid and ethylene glycol) with an unsaturated polyester modified with the reaction product of colophony or abietic acid and an alpha-unsaturated monocarboxylic acid. Reaction may be effected in presence of a solvent, catalyst or inhibitor (e.g. quinone, hydroquinone, pyrocatechol, or tert.-butyl p-cresol). The polyesters may be compounded with oils, alkyd resins, urea-formaldehyde resins, phenol-formaldehyde resins, coumarone resins, polyvinyl esters, polyacrylic esters and polystyrene. Those polyesters containing terminal hydroxyl groups may be chain-lengthened by reaction with polyisocyanates. Examples disclose unsaturated polyesters made from (1), (2), (3) and (4) maleic anhydride, a diene adduct of colophony and acrylic acid and 1 : 2-propylene glycol; (9) fumaric acid, itaconic acid, phthalic anhydride, a diene adduct of colophony and acrylic acid, 1 : 2-propylene glycol and ethylene glycol; (10) maleic anhydride, succinic acid, a diene adduct of colophony and acrylic acid, 1 : 2-propylene glycol and 1 : 4-butylene glycol. Unsaturated polyester copolymers.-The unsaturated polyesters may be copolymerized with unsaturated compounds of formula <FORM:0806730/IV (a)/1> where R1 is an aromatic, isocyclic or heterocyclic radical or a carboxylic, halogen, acyloxy, carbalkoxy or alkoxy radical or an aldehyde, ketone, nitrile, lactam or sulphonic group and R2 is halogen, alkyl or hydrogen. Specified vinyl compounds are styrene and its derivatives and homologues, divinyl benzene, N-vinyl carbazole, acrylic or methacrylic acids or their esters, amides or nitriles (e.g. acrylamide, methacrylamide, methylene - bis - methacrylamide, methyl methacrylate or ethyl acrylate), also triacyloyl perhydrotriazine, alpha-chloracrylic esters, vinyl ethers, vinyl esters (e.g. vinyl propionate), N-vinyl lactams, vinyl ketone or vinyl sulphones. Specified allyl compounds are the allyl esters of saturated mono- or polycarboxylic acids or other organic or inorganic acids (e.g. phthalic, maleic, succinic, cyanuric or phosphosphoric), also the allyl ethers of mono-or poly-hydric alcohols and the esters of chloroallyl alcohol or methallyl alcohol. In Example 8, a mixture of unsaturated polyester, N-vinylcarbazole and methacrylamide is copolymerized. Preferably the polyester has a monomer content of 20-50 per cent. Copolymerization may be effected with the aid of light (especially ultra-violet), azo compounds or peroxy compounds (with or without compounds of Pb, Mn, Co, Fe or Cr or amines as accelerators). Copolymerization may be effected in presence of cork flour, quartz flour, kieselguhr, heavy spar, graphite, antimony trioxide, glass fibres or calico fabrics.