posted on 2020-01-22, 15:34authored byXuhua He, Yuechuan Wang
Multifunctional
polymer composites with high thermal conductivity
are beneficial as thermal management materials for advanced electronics
and technologies because of their design flexibility. However, conventional
polymer composites do not possess all of the desirable material properties.
Here, using the binary fillers graphene oxide (GO) nanosheets and
hexagonal boron nitride (BN) platelets, we fabricated flexible polyimide
(PI) composite films with high thermal conductivity and excellent
thermal and electrical insulating properties. For the resultant PI
composite films, a maximum thermal conductivity of 11.203 W/(m K)
was achieved at a low filler loading of 1 wt % GO and 20 wt % BN,
approximately 50 times higher than that of neat PI films. Theoretical
models demonstrated that this synergistic enhancement resulted from
the interactions of the binary fillers. The PI composite films also
showed improved thermal mechanical properties and thermal stability
and retained electrical insulation, moderate dielectric permittivity,
and low dielectric loss.