Study on Construction Methods and Electrical Properties of Super Electrical Insulating Materials With Nanopores

The breakdown field strength and dielectric loss are the most important indexes to evaluate insulating materials. In the past two decades, the electrical properties of materials have been significantly improved by the nano-doping technique, which has been achieved milestone achievements. However, the challenge such as nanoparticles agglomeration and interface control have restricted the industrial application of nanocomposite dielectrics. It is theoretically suggested that the breakdown field strength of dielectric samples can be significantly improved by constructing nanopore structures, based on it, we designed and fabricated two kinds of insulating materials with extremely high electrical performance, that is, siloxane-based nanoporous polymer insulating material (SNPIM) and polysiloxane biocomposite insulating material (PBIM). The characteristics of pore structures and electrical performances (breakdown field strength, permittivity, and dielectric loss) were obtained, and the influence of pore structures characteristics on electrical performances was analyzed. The results indicate that the breakdown field strength of SNPIM and PBIM in
${{S}_6}$
are much higher than that of industrial ceramic fiber insulating papers (ICFIP), and the corresponding increase percentage is
$261.51{{\% }}$
and
$325.47{{\% }}$
, respectively. Besides, both SNPIM and PBIM have excellent dielectric performances whose permittivity is
$53.2{{\% }}$
and
$57.6{{\% }}$
lower than that of ICFIP, and the corresponding decrease percentage of Tan
$\delta$
were
$76.2{{\% }}$
and
$73.8{{\% }}$
, respectively.