GB905725A - Improvements in or relating to an epoxy resin composition - Google Patents

Abstract

Compositions which are curable by exposure to moisture comprise a polyepoxide and a ketimine. Long lists of a wide variety of suitable polyepoxides are given, bisphenol A/epichlorhydrin condensates being used in the examples. Similarly long lists are given of suitable ketones and primary amines are given, ketimines prepared from the following being used in the examples:-methyl ethyl, methyl isobutyl and diisobutyl ketones and methyl levulinate; ethylene diamine, diethylene triamine, tetramethylene diamine, and m-xylene diamine. The preferred method of curing is to expose the composition to an atmosphere of at least 20% relative humidity. There may also be added to the composition conventional solvents, e.g. ketones, esters, monoether alcohols, chlorinated hydrocarbons, with or without aromatic hydrocarbons and/or alcohols (lists are given), a mixture of methyl isobutyl ketone, ethylene glycol and xylene being used in the examples. Other additives mentioned are diethylphthalate, allyl glycidyl ether, phenyl glycidyl ether, styrene oxide, acetonitrile, BF3-amine complexes, unspecified anhydrides, and in the examples a polysiloxane. Uses: Coating: laminates (see Group VIII).ALSO:Ketimines which are used for curing poly epoxides (see Group IV(a)) are prepared by reacting a ketone with an amine containing at least one primary amine group. The ketimines may be aliphatic, cycloaliphatic, aromatic or heterocyclic; saturated or unsaturated; and may be substituted by chlorine, ether, ester, keto or amide groups. The following ketimines are specified:-N,N1-di(2-propylidene)-1,5-pentanediamine, N1,N5-di(2-propylidene)-3-aza-1,5-pentanediamine, N,N1-di(2 - butylidene) - 1,4-cyclohexanediamine, N1,N8-di(2-butylidene)-3,6-diaza-1,8-octanediamine, p N,N1 - di(2 - propylidene)-1,4-benzenediamine, N,N1 - di(2-proplidene)-2,2-bis(4-aminophenyl)propane, N,N1-di (2 - butylidene) - bis(4 - aminophenyl sulphone, N,N1 - di(2 - butylidene) - bis(4-aminophenyl) methane, N,N1-di(4-methoxy-2-hexylidene)-2,2-bis(4-aminophenyl) propane, N,N1-di(4-chloro-2-hexylidene)-2,2-bis(4-aminophenyl) propane, N,N1-di(4-chloro-2-hexylidene)-1,5 - pentanediamine, N,N1 - di(2 - methoxy-4-hexylidene)-1,5-pentanediamine, N,N1-di(3-allyl-6-octylidene)-1,5-pentanediamine, N1,N5-di(4-methyl-2-pentylidene)-3-aza-1, 5-pentanediamine, N,N1-di (4-methyl - 2 - pentylidene) - 1,2 - ethane diamine, N1,N5-di(2 - butylidene) - 3-aza-1,5-pentane diamine, N,N1-di(2,6-dimethyl-4-heptylidene)-m-xylylene diamine, N,N1 - di(4-methyl-2-pentylidene)-1,4-butanediamine, and N1,N5-di(1-carboxy - 3 - butylidene)-aza-1,5-pentane diamine. And an example is given of the preparation of N,N1-di(4-methyl-2-pentylidene)-m-xylylene diamine from m-xylylene diamine and methyl isobutyl ketone in benzene. Other suitable ketones and amines are listed.