Patent GB-995726-A (GB)
Title: Improvements in or relating to the production of thermo-settable epoxy resins
Inventor: WARSON HENRY
IPC: C08F18/10
Filed: 1960-08-30
Abstract: Esters of a ,b -epoxymonocarboxylic acids, containing one or more ethylenic double bonds in the acid and/or in the alcohol radical or prepared by condensing an a -halogenoacetic ester with a ketone. Condensation is preferably at low temperature in presence of sodium hydride, sodium alkoxide, sodamide, potassium terttiary butoxide or sodium as catalyst.  Ketones mentioned are methyl vinyl ketone, methyl isopropenyl ketone, vinyl levulinate, ethyl levulinate, acetone and cyclohexanone. Suitable ester starting materials are allyl monochloroacetate; the dichloroacetate of but-2-enediol-1,4; ethyl monochloroacetate. In Example (1) allyl monochloroacetate was condensed with acetone to produce allyl-b ,b -dimethyl glycidate; (2) ethyl monochloroacetate was condensed with methyl vinyl ketone to give ethyl-(b -methyl-b -vinyl glycidate); (3) ethyl monochloroacetate was condensed with methyl isopropenyl ketone to give ethyl-(b -methyl-b -isopropenyl glycidate); (4) allyl monochloroacetate was condensed with cyclohexanone to give allyl-1 : 2-epoxy-cyclohexyl acetate.ALSO:Thermosettable epoxy resins are prepared by polymerizing an ester of an a ,b -epoxymonocarboxylic acid containing one or more ethylenic double bonds in the acid and/or in the alcohol radical, if desired together with a vinyl or vinylidene comonomer. Suitable esters are produced by condensing an a -ethylenically unsaturated ketone, e.g. methyl vinyl ketone, methyl isopropenyl ketone, or vinyl levulinate, with a halogeno-acetic ester, e.g. ethyl monochloroacetate, allyl monochloroacetate, or the dichloroacetate of but.-2-enediol-1,4.  If the ester contains the ethylenic double bond, the ketone may be saturated, e.g. cyclohexanone or ethyl levulinate. The epoxyester may be polymerized or copolymerized in known manner and insolubilized with an appropriate epoxide curing agent, e.g. a mineral acid, latent acid such as ammonium phosphate, organic polyearboxylic acids or anhydrides, or organic sulphonic acids. Suitable comonomers for the epoxy esters are vinyl acetate, methyl methacrylate.  Polymerization may be in bulk, in solution, emulsion or dispersion.  In Examples: (5) allyl b b -dimethyl glycidate is polymerized with benzoyl peroxide, and the polymer cured with diethylene triamine; (6) is similar, the polymer being cross-linked by stoving at 150 DEG  C. with a little phosphoric acid or maleic anhydride; (7) methyl methacrylate was copolymerized with allyl b b -dimethyl glycidate and the polymer cured with diethylene triamine; (8) vinyl acetate was copolymerized with allyl b b -dimethyl glycidate in toluene, using benzoyl peroxide. The polymer solution dried to a film which could be insolubilized with p-toluene sulphonic acid or phosphoric acid; (9) is similar to (7), the copolymer being insolubilized with phosphoric acid; (10) an acetone solution of allyl b b -dimethyl glycidate and maleic anhydride was polymerized with benzoyl peroxide; (11) vinyl acetate was copolymerized with 1,4-but.-2-enediol di-b b -dimethyl glycidate.  The copolymer was cured with phosphoric acid or maleic anhydride; (12) vinyl acetate and allyl-b b -dimethyl glycidate were copolymerized in emulsion with potassium persulphate as an initiator. The product was cured with phosphoric acid or maleic anhydride.