Effect of Thermal Cycling on the Thermal and Mechanical Properties of Dielectric Materials

Epsilon-negative behavior and its capacitance enhancement effect on trilayer-structured polyimide–silica/multiwalled carbon nanotubes/polyimide–polyimide composites

“…The steric hindrance, which is produced by the addition of low content, reduces the mobility of the PI molecular segments and its side groups, and the interface effect is notable in the nanocomposite dielectrics, making the real permittivity and AC conductivities decrease compared with the PI-4.0 wt% MWCNTs/PI-PI composites (i.e., no doping of SiO 2 ). 47,48 The interface effect between the particles and the PI matrix will enhance with the increase of the mass fraction. The AC conductivity results are not so ideal due to the small change in the SiO 2 content gradient in samples, uniformity of samples, and the accuracy of the testing instruments.…”