A curable polymer mixture comprising 1.) at least one at least oligomeric addition product a) of at least one amino silane and/or thiosilane having at least one hydrolysable silane group to at least one compound having at least two terminal, ethylenically unsaturated double bonds, and/or at least one at least oligomeric addition product b) of at least one isocyanate silane and/or epoxy silane having at least one hydrolysable silane group to at least one oligomeric compound having at least three recurring units and at least one terminal hydroxyl group or terminal amino group and at least one terminal ethylenically unsaturated double bond as coupling additive, 2.) a system which can be cured by radical polymerisation, comprising at least one ethylenically unsaturated polymer and/or a (meth)acrylic resin, at least one ethylenically unsaturated monomer, at least one radical initiator and optionally at least one cross-linking agent as binder 3.), at least 20% by weight, preferably at least 40% by weight, more preferably at least 60% by weight, based on the total weight of the components 1.) to 4.) of the polymer mixture, of inorganic, preferably multiparticulate, fillers as aggregates, and 4.) optionally conventional auxiliaries.