GB919190A - New glycidyl ethers containing at least two epoxide groups and process for their preparation - Google Patents

Abstract

Curable mixtures comprise a glycidyl ether of an epoxy cyclic dialcohol of the formula <FORM:0919190/IV(a)/1> where R1 to R8 each represents a monovalent substituent such as a halogen or hydrogen atom or an aliphatic, cycloaliphatic, araliphatic or aromatic hydrocarbon residue, preferably an alkyl radical with 1 to 4 carbon atoms, and R1 and R5 together may also represent an alkylene group, such as a methylene group, as well as a curing agent for epoxy resins. The curable mixtures may further contain a proportion of a polyepoxide whose epoxide groups are wholly or partially hydrolysed to hydroxyl groups, and/or other polyhydroxy compounds. Other epoxides such as mono- or polyglycidyl ethers of mono- or polyalcohols or mono- or polyphenols, polyglycidyl esters of polycarboxylic acids or aminopolyepoxides, may also be present. Fillers, plasticizers or colouring matter may be incorporated. Suitable curing agents include amines or amides, polyamides, isocyanates, isothiocyanates, polyhydric phenols, phenol-aldehyde resins, reaction products of aluminium alcoholates or phenolates with compounds of tautomeric reaction, e.g. acetoacetic ester, Friedel-Crafts catalysts, phosphoric acid and, preferably, polybasic carboxylic acids and anhydrides. An accelerator such as a tertiary amine or a strong Lewis base may be added. Examples are given of all these additives. In detailed examples, (6) a mixture comprising an epoxidized mixture of glycidyl ethers of 1:1-dimethylol-cyclohexene-3 and a sodium alcoholate of 2:4-dihydroxy-3-hydroxymethylpentane is cured using a curing agent made by condensing cresyl glycidyl ether with hexahydrophthalic anhydride; similar compositions are made using an epoxidized glycidyl ether mixture of 1:1-dimethylol-6-methylcyclohexene-3 or an epoxidized diglycidyl ether of 1:1-dimethylol-cyclohexene-3; the aforementioned curing agent may also be replaced by methylendomethylene tetrahydrophthalic anhydride; (7) a diglycidyl ether of 1:1-dimethylol-3,4-epoxycyclohexane is cured using triethylenetetramine as curing agent.ALSO:The invention comprises glycidyl ethers of cyclic alcohols of the formula <FORM:0919190/IV (b)/1> where R1 to R8 each represents a monovalent substitutent such as a halogen or hydrogen atom or an aliphatic, cycloaliphatic, araliphatic or aromatic hydrocarbon residue, preferably a lower alkyl radical with 1 to 4 carbon atoms, and R1 and R5 together may also represent an alkylene group such as a methylene group. The novel glycidyl ethers may be made by subjecting the corresponding 1 : 1-dimethanol-cyclohexene-3, in any desired order of succession to treatment with an epihalohydrin or glycerol dihalohydrin, preferably with epichlorohydrin, and to epoxidation, e.g. with an organic peracid, or with HOCl followed by an agent splitting off HCl, such as a strong alkali. The reaction with epihalohydrin in one stage in the presence of strong alkali, or by first forming the halohydrin ether in the presence of an acid catalyst, e.g. boron trifluoride, which is then dehydrohalogenated by means of an alkali to form the glycidyl ether. The reaction always yields mixtures of glycidyl ethers. Mono and diglycidyl ethers can be isolated from the mixture and subjected separately to epoxidation. In examples, (1) 1 : 1-dimethylolcyclohexene-3 and epichlorohydrin are reacted to form a glycidyl ether mixture which is epoxidized with peracetic acid; (2) the monoglycidyl ether is separated from the intermediate mixture in (1) and epoxidized; (3) the diglycidyl ether of 1 : 1-dimethylol-cyclohexene-3 is similarly obtained and epoxidized; (4) a glycidyl ether mixture of 1 : 1-dimethylol-6-methyl-cyclohexene-3 is obtained and epoxidized; (5) the diglycidyl ether of 1 : 1-dimethylol-2 : 5-methylene-cyclohexene-3 is made and epoxidized.