GB820993A - Improvements in epoxide resins - Google Patents

Abstract

Cured resins are made by reacting a polyoxyalkylene glycol having a molecular weight of 600 to 6000, a glycidyl polyether containing more than one epoxide group per molecule and having an epoxide equivalent below 1000 and <PICT:0820993/IV (a)/1> a polybasic acid anhydride in excess of that required to esterify the polyalkylene glycol, the maximum amount of polyalkylene glycol depending upon both the epoxide equivalent of the glycidyl polyether and upon the molecular weight of the polyoxyalkylene glycol, the amount of polyoxyalkylene glycol of a given molecular weight being used with a glycidyl polyether of a particular epoxide equivalent in amounts not exceeding amounts represented by the area ABCD of the drawing, the polybasic acid anhydride and glycidyl polyether being used in a ratio such that there is at least 0.5 anhydride group per epoxide group. Specified glycidyl polyethers are those made by reacting polyhydric alcohols or phenols, e.g. bis-phenol, phloroglucinol and p,p1-dihydroxydiphenyl with glycerol dichlorohydrin, epihalohydrins, e.g. epichlorhydrin, 3-chloro-1,2-epoxy butane, 3-bromo - 1,2 - epoxy - hexane and 3 - chloro-1,2-epoxyoctane and glycidyl polyethers. Specified polyoxyalkylene glycols are those of the general formula HOCH2(CH2OCH2)xCH2OH, where x=12 to 140. Specified polybasic carboxylic acid anhydrides are succinic, adipic, maleic, tricarballylic, phthalic, pyromellitic, endo-cis-bicyclo-(2,2,1) - 5 - heptene - 2,3 - dicarboxylic and 1,4,5,6,7,7-hexachlorobicyclo-(2,2,1)-5-heptene-2,3-dicarboxylic anhydride. Curing catalysts, e.g. alkali or alkaline earth metal hydroxides, dimethyl aminomethyl phenol and benzyl trimethyl ammonium hydroxides may be used. The Specification describes the preparation of glycidyl polyethers from epichlorohydrin and (A) glycerol, (B) to (D) bis-phenol, (E) 2,2-bis-(4-hydroxy phenyl) propane, (F) resorcinol, (G) p,p1 - dihydroxydiphenyl and (H) p,p1 - di - hydroxydiphenyl sulphone. Examples (1) to (12) describe the curing of various glycidyl polyethers using various polyoxyalkylene glycols and phthalic, maleic, pyromellitic, endo-cis-bicyclo - (2,2,1) - 5 - heptene - 2,3 - dicarboxylic and 1,4,5,6,7 - hexachlorobicyclo - (2,2,1) - 5 - heptene-2,3-dicarboxylic anhydride whilst in Examples (13) and (14) glycidyl polyether B is reacted with a polyoxyethylene glycol of molecular 4000, phthalic acid, glycerin and methyl isobutyl ketone to form a resinous intermediate which is cast as a film and cured in the presence of dimethylaminophenol or butylated urea formaldehyde resin. The products of the invention may also be used for moulding. Specifications 675,169, 675,170 and 679,536 are referred to.