Curing agent for epoxy resins, comprising A) 1-99 wt % of an adduct obtainable by reaction of a1) a polyethylene polyamine having up to five nitrogen atoms in the molecule, with a2) a monoglycidylether, wherein the adduct of a1) and a2) is isolated by removing the excessive polyethylene-polyamine, and B) 99-1 wt % of an amine compound having at least two reactive amine hydrogen atoms in the molecule, as well as curable compositions additionally comprising an epoxy compound and the use of said curable compositions for the preparation of moulded articles and sheet materials, as well as for applications in the field of adhesives and sealing compounds.