Electrostatic flocking assisted aligned boron nitride platelets scaffold for enhancing the through-plane thermal conductivity of flexible thermal interface materials

Abstract

The composite films filled with anisotropic flaky powders usually have excellent in-plane thermal conductivity, but poor through-plane thermal conductivity. To improve the through-plane thermal conductivity, vertically aligned boron nitride (BN) platelets are scaffolded through electrostatic flocking together with flexible epoxy resin. 17.57 wt% BN loading of the BN/epoxy complexes exhibit 0.65 W/m K of through-plane thermal conductivity, which is 18.6% higher than the random BN/epoxy. The method effectively utilizes each anisotropy of the two-dimensional material BN, exploiting the higher thermal conductivity of BN in-plane, and providing a new strategy for the preparation of thermal interface materials.