Research on the Improvement of Thermal Aging Resistance of Polypropylene Cable Insulation Based on Antioxidant Grafting

To improve the thermal aging resistance of polypropylene (PP) blended elastomer composites, this study investigated the effect of antioxidant-grafted PP on PP blended with polyolefin elastomer (POE). The physical, chemical, and mechanical tensile properties of the graft-modified materials were tested before and after thermal aging, and comparisons were made in terms of volume conductivity and direct current (DC) breakdown strength. The results showed that graft modification significantly extended the oxidation induction time and improved the mechanical tensile strength after aging. After 60 days of aging, the grafted samples exhibited a smaller increase in conductivity and a smaller decrease in breakdown strength, outperforming the ungrafted samples at both room and elevated temperatures. These findings indicate that grafting antioxidants can effectively enhance the aging resistance of polypropylene composite insulation materials