Based on electrostatic adsorption constructing neural network-like structure of BNNS-OH@CNF composite films with excellent thermal management and electrical insulation performance

Abstract

Due to the rapid development of electronic devices, there was an urgent need for polymer composite materials with excellent heat dissipation capabilities to solve the heat dissipation problem of electronic devices. However, designing an insulation composite material with simple processing methods, low cost, and high thermal conductivity and excellent mechanical properties remained a challenge. Inspired by the human nervous system, this article used cellulose nanofibers (CNF) as a template and adsorb hydroxylated boron nitride nanosheets (BNNS–OH) through a simple electrostatic self-assembly method, and prepared composite film through vacuum filtration. The BNNS-OH@CNF composite film generated a thermal conduction network similar to the human nervous system, and can achieve a maximum thermal conductivity of 10.7 W m⁻¹ K⁻¹ when the filler load was 60 wt%. It had good electrical insulation performance and a volume resistivity of 7.7 × 10¹³ Ω m. The most important thing was that the tensile strength of 34.2 MPa can still be maintained at such a high filler load. In addition, the composite film also exhibited good thermal management capabilities. This had significant application potential as a thermal management material.