Abstract: The permeability of polymeric articles, particularly fuel tanks and fuel canisters is substantially reduced by thin varnish coatings comprising an epoxy resin, an amine containing curing agent and a flexibilizer.

Abstract: A method for obtaining a positive bond between articles painted or coated with thermosets and concrete, involves treatment of the surface with an epoxy resin-cement mortar mixture containing an epoxy resin emulsion of the composition(a) a liquid epoxy resin;(b) water;(c) an emulsifier comprising a primary, aliphatic alcohol, an adduct thereof with ethylene oxide or, optionally, a polyglycol ester of a carboxylic acid; and(d) a latent curing agent comprising a reaction product of the essentially complete neutralization of a diamine of the formulaeH.sub.2 N--CH.sub.2 --R--NH.sub.2orH.sub.2 N--R--CH.sub.2 --R--NH.sub.2with oxyalic acid,wherein R is alkyl substituted alkylene or cycloalkylene; or the reaction product obtained by complete neutralization with oxalic acid of (i) a polyamine of the formulaH.sub.2 N--CH.sub.2 --CH.sub.2 --NH--.sub.x Hwherein x=2, 3, or 4, or of (ii) a reaction product, containing amino groups, of such a polyamine with a fatty acid.

Abstract: Epoxy resin-diammonium salt emulsions are based on a liquid epoxy resin, a latent curing agent, and an emulsifier. The latent curing agent comprises diammonium oxalates and the emulsifiers are C.sub.8 - to C.sub.14 - alcohols and/or the adducts thereof with up to 10 ethylene oxide groups. A process for the production of such emulsions is provided. They are useful in epoxy resin mortars and epoxy resin-cement mortars, and for the sealing of concrete surfaces.