The disclosure relates to a composition having at least one radically polymerisable monomer M; at least one radical former, at least one epoxide resin A including an average of more than one epoxide group per molecule, and at least one compound of formula (I). Such compositions are suitable as adhesives, sealants or coatings. Shortly after the application thereof, they have a high initial strength and, after further hardening at room temperature, they reach a high level of final strength.