The invention relates to an adhesive film which comprises a layer of an adhesive that comprises one or more polymers and at least one peroxide, characterized in that the adhesive comprises at last 50% by weight of thermoplastic polymers that do not have C═C multiple bonds, in that at least one peroxide has the general structural formula R—O—O—R′, wherein R and R′ each represent organyl groups or together represent a cyclic organyl group, and in that the peroxide in solution has a 1-minute half-life temperature of less than 200° C. In a preferred embodiment, the thermoplastic polymer is a polyurethane and the peroxide is a dicumyl peroxide.