Ethylene propylene diene copolymers can be thermoplastically extruded. By cross-linking, profiles with rubber-like properties frequently used as sealing profiles are obtained in a low-cost manufacturing technique. EPDM is non-polar. For this reason, bonding without pretreatment cannot achieve sufficient adhesion values. By means of plasma activation, the surface tension can be increased to more than 72 mN/m to ensure perfect bonding.