A method for producing a polymer-metal oxide composite material resistant to degradation resulting from exposure to gamma irradiation, the method comprising exposing a composite precursor comprised of a heat-resistant polymer in which metal oxide nanoparticles are incorporated to gamma irradiation of at least 1 MRad in a flowing gas atmosphere for a period of at least 12 hours. The resulting radiation-resistant composite material and shaped articles of the material are also described.
 This invention was made with government support under Prime Contract No. DE-AC05-00OR22725 awarded by the U.S. Department of Energy. The government has certain rights in the invention.