this invention provides biodegradable , biocompatible polymeric films having uniform selected thicknesses between about 60 micrometers and about 5 mm useful in the manufacture of therapeutic implants for insertion into a patient &# 39 ; s body . the films may be shaped to cover implants made of other materials to improve their biocompatibility . the films may be coated with or incorporate bioactive agents . they may have differing properties , e . g ., porosity , thickness , and degradation rate , in different areas .