| 摘要 |
A hardenable composition comprises a mixture of (1) a glycidyl polyether and (2) a curing catalyst therefor comprising from 0,5 to 50% by weight, based on the weight of polyether, of a nitrogen co-ordinated boron compound of the formula <FORM:0927006/IV(a)/1> wherein R is selected from -CH2-CH2 and -CH(CH3)CH2-and R1 and R11 are selected from hydrogen, alkyl radicals, cycloalkyl radicals and aryl radicals. A hard, cured resinous product is produced by heating this mixture within the range 80 DEG to 150 DEG C. The glycidyl polyethers are made by reacting at least one polyhydric phenol and an epihalohydrin in an alkaline medium. Suitable phenols are polynuclear phenols such as bisphenol 'A' and 4,41-dihydroxydiphenyl methane, in admixture with which may be used, for example, 4,41-dihydroxy diphenyl sulphone. Solutions of the glycidyl polyethers and curing catalysts can be applied to electrical wires, cables, coils and windings as potting, impregnating and coating resins and varnishes. The compositions comprising glycidyl polyethers and curing catalysts are adhesives. They can also be admixed with solids such as silica, titania, glass fibres, wood flour, zirconia, graphite and calcium silicate. Amounts of up to 50% of the composition of other resins such as phenolics, polyesters, glycol maleates and alkyd resins can be admixed with the glycidyl polyethers.ALSO:Alkanolamine borates of the formula <FORM:0927006/IV(a)/1> where R is -CH2-CH2 or -CH(CH3)-CH2- and R1 and R11 are hydrogen atoms, alkyl radicals, aryl radicals or cycloalkyl radicals are made by reacting three mols of a mono-alkanolamine for each mol of boric acid or boric ester at an elevated temperature of about 60 DEG C. to 140 DEG C. The water or alcohol by product may be distilled off during the reaction. When boric acid is used, azeotroping solvent such as benzene, toluene, and xylene may be used to remove the water. In examples are reacted (1) monoethanolamine and methyl borate, (2) monoisopropanolamine and boric acid, (3) N-methyl ethanolamine and ethyl borate, (4) N,N-dimethylethanolamine and methyl borate, (5) N,N-diethyl ethanolamine and methyl borate and (6) N,N-dimethyl ethanolamine and triisopropyl borate. Other specified reactants are n-propyl, n-butyl, cyclohexyl, o-cresyl, m-cresyl, m,p-cresyl, phenyl, and benzyl borates; N-methyl isopropanolamine, N,N-dimethyl isopropanolamine, N-ethyl ethanolamine, N,N-diethyl isopropanolamine, N-phenyl ethanolamine, N,N-diphenyl ethanolamine, N,N-diisopropyl ethanolamine and N,N-di-(2-ethylhexyl) ethanolamine. Other possible radicals for the alkanolamine and for the borate ester are specified including halogenated phenyl radicals such as chlorophenyl. |
