Patent GB-741633-A (GB)
Title: Improvements relating to unsaturated phenolic compounds and condensation products thereof
Filed: 1953-08-06
Abstract: Condensation products suitable for use in coating compositions are made by condensing a compound of the general formula <FORM:0741633/IV(a)/1> where R is an alkyl or hydroxy alkyl group, R1 is an alkenyl radical and n is an integer from 1 to 3, made by reacting the alkenyl phenol with formaldehyde and etherifying the resulting methylol product (see Group IV (b)), or by condensing mixtures of such compounds.  Suitably R is methyl, ethyl, propyl, isopropyl, butyl, hexyl, hydroxyethyl or hydroxybutyl; R1 is vinyl, allyl, methallyl or butenyl and n is 2, or where mixtures of the methylol phenyl ether is used, at least 50 per cent of the mixture consists of compounds wherein n is 2.  For the preparation of coating compositions an acid substance such as sulphamic acid, aniline sulphate, urea hydrochloride, morpholine sulphate or p-toluene sulphonic acid is added to the alkenyl methylol phenyl ether as a condensing agent, preferably in the form of a solution in methanol or ethanol and preferably in amount of from 0.001 to 0.05 per cent of the alkenyl methylol phenyl ether; the mixture may then be bodied at 175-225 DEG  C. for from 30 minutes to two hours and is dissolved in a solvent such as benzene or toluene. Conventional driers may be added.  The alkenyl methylol phenyl ethers and their condensation products may also be copolymerized with other unsaturated materials such as styrene, unsaturated polyesters, triallyl cyanurate, diallyl phthalate and vinyl acetate.  In an example, a low viscosity oil which comprises a mixture of 2-allyl-4-methylol anisole, 2-allyl-4 : 6-di-methylol anisole and 2-allyl-6-methylol anisole is heated in the presence of sulphamic acid and the partly condensed product is dissolved in toluene with the addition of cobalt and lead naphthenate driers to form a coating composition.  Other alkenyl methylol phenyl ethers which may be employed in coating compositions are specified together with specified pigments and drying agents.ALSO:The invention comprises phenolic ethers of the general formula <FORM:0741633/IV(a)/1> where R is an alkyl or hydroxyalkyl radical, R1 is an alkenyl radical and n is an integer from 1 to 3, and mixtures thereof.  Compounds in which n is 2 are preferred, and preferably constitute at least 50 per cent of the total in the case of mixtures.  Suitably R may be a methyl, ethyl, propyl, isopropyl, butyl, hexyl, hydroxyethyl or hydroxybutyl radical and R1 may be a vinyl, allyl, methallyl or butenyl radical.  The compounds may be made by dissolving an alkenyl phenol in an alkaline solution, adding formaldehyde (preferably about 1.5-2.2 mols. per mol. of the phenol), or paraformaldehyde, stirring the mixture at or below room temperature or at about 25-65 DEG  C. until the reaction is complete, and etherifying the resulting methylolphenol or mixture thereof, e.g. with dimethyl sulphate, an alkyl halide or a chlorhydrin.  In an example, o-allylphenol is warmed with 2.2 molecular proportions of aqueous formaldehyde in caustic soda solution and the product is heated with dimethyl sulphate to produce a mixture probably containing 2-allyl-4:6-dimethylolphenyl methyl ether and minor amounts of the 4- and 6-monomethylol compounds.