Enhanced high thermal conductivity and low permittivity of polyimide based composites by core-shell Ag@SiO_2 nanoparticle fillers

摘要

A kind of polymer based composites was prepared by embedding the fillers of core-shell Ag@SiO_2 nanoparticles into the polyimide (PI) matrix. The obtained Ag@SiO_2/PI (50% vf of fillers) composites show remarkably improved high thermal conductivity and low relative permittivity. The maximum value of the thermal conductivity of composites is 7.88W/(mK) and the relative permittivity and dielectric loss are about 11.7 and 0.015 at 1MHz, respectively. Compared with self-passivated nanometer Al* particles composites, core-shell Ag@SiO_2 nano-composite is beneficial to increase the thermal conductivity and reduce the permittivity of the composites. The relative mechanism was studied and discussed.