High‐Voltage Electrothermal and De‐Icing Performance of Separated Structured Carbon Black/Silicone Rubber Composites Exhibiting Electric Field Emission

ABSTRACT Internal electric field emission has been reported to occur when carbon blacks (CBs) are separated by a narrow insulating gap in previous researches. However, the electrothermal performance (ETP) of composites incorporating spatially separated CBs remains unexplored. Herein, a record‐high ETP at high‐voltage (power density [Pd] up to 4.94 W/cm 2 at 1000 V) is obtained by fabricating a non‐percolative structure super‐conductive carbon black (SCB)/methyl vinyl silicone rubber (MVQ110‐2) composite, significantly surpassing that of SCB/XLPE, CNT‐based, and rGO‐based composites. This results in a temperature increase up to 114°C. The outstanding ETP at high‐voltage arises from Joule heating generated by electric field emission effect among the isolated SCB aggregates, combined with high electrical breakdown resistance. This resistance is attributed to the separated structure, low dielectric constant of MVQ110‐2, and strong interfacial bonding between SCB particles and the polymer matrix. Combined with high breakdown voltage and efficient Joule heating, a de‐icing efficiency of 4.6 min at −20°C is achieved at 1000 V for the 2.1 vol.% SCB/MVQ110‐2 composite. Furthermore, these composites possess excellent flexibility at −20°C. Therefore, it can be concluded that these SCB/MVQ110‐2 composites are promising for high‐voltage electrothermal de‐icing applications, such as on transmission lines.