In cable accessories

a heterogeneous interface is formed between the insulating silicone rubber (SiR) and the cross-linked polyethylene (XLPE) cable insulation. To ensure sealing performance and lubrication during installation

silicone grease is applied at the interface. However

during long-term operation

the grease tends to slip and swell the SiR

degrading the interface's electrical endurance and posing a discharge hazard. In this study

a silicone grease matrix compatible with the main insulation and accessory insulation is first selected through comparative analysis of fundamental electrical properties. Subsequently

an organic molecular semiconductor filler

2

3

5

6—tetrafluoro—7

7

8

8—tetracyanoquinodimethane (F4TCNQ)

featuring a low lowest unoccupied molecular orbital (LUMO) level and a wide bandgap

is introduced into the silicone grease. The results show that the fully organic modified silicone grease increases the heterogeneous interface breakdown voltage by 1.56 kV (at 0.3 MPa). Owing to the energy level difference between F4TCNQ and the silicone grease

carrier traps are established at the heterogeneous interface

thereby suppressing carrier transport. Moreover

the strong intermolecular forces among F4TCNQ molecules inhibit grease slippage. Through the synergistic effect of carrier transport regulation and slip suppression

the electric strength of the SiR/XLPE heterogeneous interface is significantly enhanced.