Predicting LDPE’s cross-linking performance with reaction mechanism and matching principles between radicals and LDPE chains

A quantitative structure-property relationship model linking the LDPE molecular chain structural parameters and its crosslinking performance plays a pivotal role in the development of LDPE base resins for ultra-high voltage cables. Based on the LDPE crosslinking mechanisms and the matching rules between free radicals and LDPE molecular chains, this work established a predictive model correlating LDPE molecular chain structure, dicumyl peroxide (DCP) dosage, and gel properties (including gel content and crosslink density). The model's accuracy and universality were rigorously validated using experimental data and relevant literature. Furthermore, this study assessed the practical utility of the model, and established the optimization workflow for crosslinking formulation design and molecular chain structure refinement. Selected optimization results are exemplified, and the theoretical explanation for the superior scorch resistance of narrow molecular weight distribution LDPE is given. This work will offer critical theoretical guidance for developing next-generation insulating materials for ultra-high voltage cables.