Study on Oxidation Mechanism of Copper Conductor in Chemically Cross-linked Cables and Collaborative Protection System

In response to the problem of oxidation discoloration of copper conductors in XLPE insulated cables during the chemical crosslinking process, this study revealed the main cause of oxidation through mechanism analysis: In addition to the high-temperature environment, the catalytic oxidation triggered by the migration of peroxide crosslinking byproducts (phenolic, aldehyde, and ketone small molecules) towards the conductors is the core inducement. An innovative “conductor-insulation collaborative protection” system is proposed: On the conductor side, high-temperature resistant benzotriazole (BTA) passivation (0.3% concentration) is applied and semi-conductive nylon tape is wrapped; On the insulation shielding side, the material formulation is optimized (adding an anti-aging agent MB/DNP compounding system); At the process end, nitrogen segmented protection and precise control of crosslinking parameters are implemented. Industrial verification shows that this solution reduces the oxidation rate of conductors by 92%, providing a dual theoretical-technical solution for industry pain points.