Evaluation and analysis of activation energy and aging life of polypropylene insulation material by TGA method

Thermoplastic polypropylene(PP) has excellent electrical and thermal properties. It does not require cross-linking and degassing in the production process of power cable insulation, meanwhile, the energy consumption of the production process is low. The material is recyclable and can be used as cable insulation material. In this paper, the medium voltage polypropylene cable insulation material was studied with thermogravimetric analysis (TGA). A proper number of polypropylene insulation materials were kept at $280^{\circ}\mathrm{C}, 290^{\circ}\mathrm{C}, 300^{\circ}\mathrm{C}, 310^{\circ}\mathrm{C}$ for a certain time, and we got the thermogravimetric curve of polypropylene. We calculated the time when the thermostatic weight loss is 5%, 10% and 15%. By linear fitting with Arrhenius equation, activation energy and life equations of polypropylene with 5%, 10% and 15% weight loss were obtained. Therefore, it is inferred that the thermal aging service life of polypropylene insulation cables at the highest operating temperature is 30 years, which can meet the requirements of power cable. The activation energy of polypropylene insulation material was verified by owaza and kissinger method. The research in this paper will provide certain technical support for the aging life for long-term operation of polypropylene insulation materials.