Abstract:
Compositions hardenable upon addition of a hardening agent comprise condensates of polyhydric compounds with epichlorhydrin or dichlorhydrin having a viscosity of at least 100 poises at 25 DEG C. and an average number of epoxy groups per molecule greater than 1.0, in admixture with sufficient cyano substituted hydrocarbon melting below 10 DEG C. to reduce the viscosity to between 1 and 80 poises at 25 DEG C. Suitable cyano-substituted hydrocarbons are acetonitrile, propionitrile, butyronitrile, methyl ethyl acetonitrile, isovaleronitrile, capronitrile, lauronitrile, p acrylonitrile, methacrylonitrile, cis-and trans-crotonitrile, allyl cyanide, oleonitrile, elaidonitrile, propiolonitrile, glutaronitrile, adiponitrile, suberonitrile, allyl malononitrile, cyclohexylcyanide, benzonitrile, o-toluonitrile, and phenylacetonitrile or mixtures thereof. The condensates may be as described in Specifications 680,997, 681,001 and 681,991. The glycidyl ethers used may be derived from polyhydric phenols or polyhydric alcohols, or mixtures of both kinds. Suitable compositions may contain 50-80 per cent by weight of phenolic ether, 10-40 per cent of alcoholic ether and 1-30 per cent of nitrile. Dyes, pigments and/or fillers may be included, e.g. zinc oxide, silica, alumina, clay or bauxite. Known hardening agents may also be included. For adhesive purposes the compositions containing a hardening agent are spread, the surfaces joined and the composition cured, if desired, at raised temperature. Examples describe a number of different compositions and their uses for adhesive purposes. Specifications 629,111, 630,647 and 630,663 also are referred to.