Temperature-dependent synergistic antioxidants for high-efficiency modulation of anti-scorch performance and crosslinking degree in peroxide-initiated low-density polyethylene

The contradiction between anti-scorch performance and crosslinking degree severely limits further development of cable insulation. To address this issue, synergistic antioxidants are proposed to modulate crosslinking reactions in peroxide-initiated low-density polyethylene (PLDPE). The results demonstrate that the combination of antioxidant 300 and antioxidant 736 achieves an extraordinarily excellent anti-scorch performance in a highly crosslinked PLDPE. The infrared spectroscopy and molecular simulation provide evidences for the existing hydrogen bond and proton transfer effects between the two antioxidants. The reactivity activity of antioxidants determined by these temperature-dependent synergistic effects effectively modulates crosslinking reactions under different temperatures, contributing to excellent anti-scorch performance and crosslinking degree in PLDPE.