bio - decomposable polymer composition shows good thermal decomposition , wherein a drop of weight - average molecular controls within 30 % of the initial after treatment of molding and radial sterilization , by adding free radical scavenger to the bio - decomposable polymer , in order to resolve the problem . bio - decomposable polymer composition of the invention , standing thermal and radial decompositions is possibly applied for medical and many other industrial uses . moreover , this processing method is applied for non - bio - decomposable polymer fields such as nylon or polypropylene for sterilization of thermal casting and irradiation .