With the development of particle reactor technology

the problem of excessive rigidity and insufficient toughness of polypropylene can be solved by in-situ reactive blending of impact polypropylene copolymer (IPC)

which holds promise of being an environmentally friendly solution for high-voltage direct current cable insulation materials. This study focuses on four different domestically produced IPCs

systematically characterizes their physical

mechanical

and DC electrical properties from molecular structure to microstructure to macroscopic perspectives of high-voltage direct current cable insulation materials

and compares the key performance of IPCs with XLPE insulation material for DC cable. Experimental results indicate that an increase in ethylene content facilitates the formation of more rubber phases

effectively enhancing the material's toughness and slightly increasing its viscosity but lowering its maximum heat-resistant elongation temperature. Regarding DC electrical performance

the increase in ethylene content and rubber phase helps reduce the temperature sensitivity of its conductivity. However

the space charge characteristics of IPC materials at high temperatures are obviously inferior to those of XLPE

indicating a problem that needs to be solved in future research.