The present invention relates to an implantable material having at least one external surface grafted with a polymeric film comprising carboxylate and sulfonate functions wherein the film is produced by copolymerization-like reaction of a source of carboxylate functions and a source of sulfonate functions. The invention also relates to a process for grafting of a polymeric film according to the invention onto at least one external surface of an implantable material. The invention further relates to the use of a grafted implantable material for the manufacture of an antiproliferative and/or antibacterial implantable medical device.