Aging Behavior of Flame-retardant Cross-linked Polyolefin under Thermal and Radiation Stresses

In this study, flame-retardant cross-linked polyolefin, which is an important polymeric insulation material for electric power cables, is aged under severe thermal and radiation stresses. After aging, the samples are analyzed mechanically, thermally, and electrically. The degradation of this polymer is found to become very severe when it is aged thermally than when aged by a combination of heat and gamma irradiation. The formation of densely cross-linked structures, induced by the gamma irradiation, appears to make the polymer harder and more resistant against oxidation and against its resultant scission of chemical bonds.