| 摘要 |
1281050 Coated product REICHHOLD-ALBERT-CHEMIE AG 1 Oct 1969 [8 Oct 1968] 48186/69 Heading B2E [Also in Divisions C3 and C7] Water-soluble synthetic resins useful as binders for coating compositions suitable for application to substrates, such as timber, concrete, glass, brickwork, plaster iron, steel and non-ferrous metals, are prepared by (a) etherifying an epoxide compound of the formula in which n is an integer, with an unsaturated monohydric alcohol containing at least one ethylenic double bond and having from 3-20 carbon atoms, by heating, preferably in the presence of a catalyst, in proportions such that at least 1.2 hydroxyl groups are present in the reaction per epoxide group; (b) copolymerising the etherified product with an ethylenically unsaturated mono- or poly-carboxylic acid or an anhydride or half-ester thereof, optionally together with one or more other vinyl or vinylidene compounds, by heating, to produce a product having an acid number of at least 25 and a viscosity of 95-800 cp. (measured as a 50% by weight solution in glycol n-butyl ether at 20‹C); and (c) neutralising the copolymerisation product at least partially with aqueous ammonia or a strong organic nitrogen base (defined as being a secondary or tertiary amine which in the form of a 50% aqueous solution has a pH of at least 9). The epoxide compound preferably has a molecular weight of 380 to 3500. Etherification is suitably effected with an alcohol such as allyl alcohol, geraniol, farnesol, soya alcohol or linseed oil alcohol. Acid comonomers specified are acrylic, methacrylic, cinnamic, #-benzoylacrylic, crotonic, maleic, fumaric, citraconic, itaconic, mesaconic and aconitic acid, and anhydrides, and mono-esters of the specified polycarboxylic acids. Optional comonomers include acrylate, methacrylate, ethacrylate and phenacrylate esters, styrene and its substituted derivatives, (meth) acrylamide and (meth) acrylonitrile. Copolymerisation can be effected with or without a solvent using, for example, di-t-butyl peroxide or cumene hydroperoxide as initiator, optionally together with a chain transfer agent such as lauryl mercaptan and, if desired, a cobalt (II) salt as accelerator. The copolymer product is neutralised with ammonia or an amine such as trimethylamine, triethylamine, diisopropanolamine, triisopropanolamine, diglycolamine, diethylamine, piperidine, morpholine, diethanolamine, N,N-dimethyl-ethanolamine, N-methylethanolamine and N, N, N', N'- tetrakis (2-hydroxypropyl)- ethylene diamine. The polymers obtained are useful as binders, either alone or mixed with other binders, in air-drying coating compositions. Such compositions may include cobalt driers, pigments, e.g. red iron oxide, carbon black, lead silicochromate, strontium chromate, blanc fixe, barytes, microtalc, colloidal chalk, diatomaceous earth, china clay, titanium dioxide, chromium oxide, zinc oxide, zinc chromate, lead carbonate, basic lead sulphate, red lead and calcium plumbate; phenol resols and/or aminoplasts, e.g. a phenol resol obtained from p-t-butylphenol and formaldehyde, etherified with n-butanol and then treated with dimethylolopropionic acid or hexamethoxymethylmelamine heated, with or without n-butyl glycollate and n-butanol, in the presence of ptoluene sulphonic acid; styrene-butadiene copolymers; vinyl acetate polymers and copolymers; and acrylate copolymers.
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