Non-oxidizing polymeric medical implant

A method for producing a medical implant made from an olefinic material having a molecular weight of between 400,000 and 10,000,000 comprising the steps of:

• forming the implant from the olefinic material;
• packaging the formed implant in an inert atmosphere;
• radiation sterilizing said packaged implant while maintaining said inert atmosphere;
• and
• heating said packaged implant while maintaining said inert atmosphere for at least 48 hours at a temperature of about 37.degree. C. to about 70.degree. C.

A method for producing a medical implant from an olefinic material having a molecular weight greater than 400,000 comprising the steps of:

• sealing the implant in an oxygen impermeable package in an oxygen reduced atmosphere having an absence of agents which can react with free radicals in the polymeric chain;
• radiation sterilizing said packaged implant;
• and
• heating said sealed packaged implant for a predetermined time and temperature sufficient to form cross-links between free radicals in neighboring polymeric chains.

A method for producing a medical implant made from olefinic material having a molecular weight greater than 400,000 comprising the steps of:

• sealing the implant in an oxygen impermeable package in an inert atmosphere;
• radiation sterilizing said packaged implant;
• and
• heating said packaged implant for at least four hours at a temperature of between 37.degree. C. and the melting point of said olefinic material to form cross-links between free radicals in neighboring polymeric chains.

A method for producing a medical implant formed from an olefinic material comprising the steps of:

• forming the implant from an olefinic material having a molecular weight of 400,000 to 10,000,000;
• sealing the formed implant in an oxygen impermeable package in a substantially oxygen-free atmosphere;
• radiation sterilizing said packaged implant;
• and
• heating said sealed package implant for a predetermined time and temperature sufficient to form cross-links between free radicals in neighboring polymeric chains.

A method for producing a sterile polymeric medical implant having improved oxidation resistance comprising the steps of:

• sealing a polymeric medical implant in an oxygen-free atmosphere contained in a container comprising an oxygen impermeable composition;
• sterilizing said implant by irradiation;
• and
• heating said package and implant at a sufficient temperature and for a sufficient time to inactivate any residual free radicals and/or free radical precursors.