Polymeric materials widely used in safety-related equipment are relatively vulnerable to severe environments such as high temperature and radiation environment during the severe accident. Therefore, to ensure the integrity and performance of the safety-related equipment, degradation effect of severe accident on polymer must be investigated.

In this paper, to evaluate the degradation effect of radiation and heat during normal operating condition and severe accident environment, hardness measurement and tensile test were carried out. And FT-IR analysis was conducted to investigate the molecular structure and bonds. The mechanical properties were not changed significantly in pre-aging, normal operating condition. But radiation of severe accident environment significantly affects the mechanical properties of fluoroelastomer and molecular structure, such as C=O formation.