Patent GB-777385-A (GB)
Title: Process for preparing diethers of a methylol-substituted diphenylol alkanes as well as hardenable compositions containing such diethers
IPC: C07C37/20
Filed: 1955-02-14
Abstract: A hardenable composition is prepared by mixing with a glycidyl polyether having an average number of 1,2-epoxy groups per molecule of more than 1.0 and derived from a polyhydric phenol with one or more diethers of polymethylol diphenylol alkanes (see Group IV (b)) and an acid curing agent, e.g. phosphoric, oxalic, p-toluene sulphonic and benzene disulphonic acids or butyl dihydrogen phosphate.  Lacquer solvents such as ketones, esters and aromatics and pigments, other resins, e.g. polyvinyl acetal resins, e.g. of saturated aldehydes with 2 to 4 carbon atoms, plasticisers and dyes may be incorporated.  Preferred glycidyl polyethers are those having a molecular weight of 1200-4000.  In examples: A coating composition comprising a glycidyl polyether with about 1.45 epoxy groups per molecule and a molecular weight of about 2900, the ethyl ether of ethylene glycol acetate, toluene, the diallyl ether of tetramethylol 2,2-diphenylol propane and phosphoric acid dissolved in butanol is sprayed on iron panels and stoved after evaporation of the solvents (III); and a coating composition comprising the above glycidyl polyether, phosphoric acid, the ethyl ether of ethylene glycol acetate, toluene and a solution of polyvinyl butyral resin in butanol is cured by heating on a glass plate.ALSO:A process for preparing a diether of a polymethylol-diphenylol alkane in which a dialkali metal salt of a diphenol of the general formula <FORM:0777385/IV(b)/1> wherein X is H or -CH2OH, at least 2 X's being -CH2OH and m is any integer, is reacted with a halohydrocarbon of the general formula R-Hal, wherein R is an aliphatic, cycloaliphatic or aryl-substituted aliphatic hydrocarbon group, which may or may not be saturated and Hal is a halogen atom.  The carbon chain CmH2m may be branched. The two methylol-substituted phenylol groups are preferably linked to the same carbon atom of the CmH2m group, e.g. as in tetramethylol-2, diphenylol propane.  Halide starting materials specified are propyl, butyl, heptyl, allyl, methallyl, crotyl, 2-pentenyl, 2-methyl-2-butenyl, 2-hexenyl, cyclohexyl, methylcyclohexyl and benzyl halides, preferably allyl chloride. The diallyl ether of tetramethylol-2,2-diphenylolpropane is prepared by reacting the disodium salt with allyl chloride at an elevated temperature. Hardenable compositions are produced by mixing one or more of the above diethers with a glycidyl polyether having an average number of 1,2-epoxy groups per molecule of more than 1.0 and derived from a polyhydric alcohol (see Group IV (a)). In examples: (I) and (II) the diallyl ether of 2,2-diphenylolpropane containing an average of about 3.5-methylol groups per molecule is obtained by reacting allyl chloride with a diphenylol propane substituted with about 3.5 methylol groups per molecule in ethanol and in the presence of sodium hydroxide.  The methylol substituted 2,2-diphenylol propane is obtained by reacting 2,2-diphenyl propane with formalin in the presence of aqueous sodium hydroxide, treating the reaction mixture with sulphuric acid and carbon dioxide, absorbing the product in acetone and separating water and acetone under reduced pressure. Glycidyl polyethers are prepared by reacting one or more polyhydric phenols, e.g. 2,2 - bis - (4 - hydroxyphenyl) propane, with epichlor- or dichlorohydrins, or the corresponding bromo compounds, in an alkaline medium.