Enhanced thermal conduction of hybrid filler/polydimethylsiloxane composites via a continuous spatial confining process

Owing to the rapid development of the electronics and aerospace industry toward high integration and power, the growing demand for heat dissipation management materials was urgent. However, the continuous fabrication of thin highly thermally conductive polymer composites at a large scale remains challenging, especially requiring control of the filling content of fillers. Herein, the continuous spatial confining forced network assembly (CSNA) method was applied to realize the continuous construction of thermally conductive networks of hexagonal boron nitride (h-BN) and multi-walled carbon nanotubes (MWCNT) in polydimethylsiloxane (PDMS) matrix. The thermal conductive composites presented thickness-dependent in-plane thermal conductivity ( K ), reaching 4.28 W m −1 K −1 for h-BN (30 wt%)/MWCNT(2 wt%)/PDMS in 0.15 mm thickness. The h-BN/MWCNT/PDMS composite represented a 1543.5% increase compared to the pure PDMS thanks to the CSNA method and the bridging connection of MWCNT. This work provided a facile method to prepare the thin high thermal conductive composites, which might promisingly advance the industrialization of thin thermosetting thermal conductive composite films. • A continuous spatial confining forced network assembly method was proposed for the fabrication of functional PDMS composites. • The composite achieved a high thermal conductivity of 4.28 W/mK with 30 wt% h-BN and the additional 2 wt% MWCNT. • The h-BN/MWCNT/PDMS composites represented potential application of electronic devices as thermal interface materials. • Continuous SCFNA presented a facile and feasible method for continuous fabrication of thermally conductive composites.