Synergistic enhanced thermal conductivity of polydimethylsiloxane composites via introducing SCF and hetero-structured GB@rGO hybrid fillers

With the fast development of high integration of electronic devices, the problem of heat accumulation has become increasingly prominent. The demand for thermal interface materials (TIMs) with high thermal conductivity (λ) is increasing for effectively solving the problem of heat transfer between heat source and heat sink. In this work, we report a short carbon fiber/glass bubble coated reduced graphite oxide/polydimethylsiloxane (SCF/GB@rGO/PDMS) composite with outstanding comprehensive performances fabricated by spatial confining forced network assembly method (SCFNA). Based on our earlier experience, we select a constant content of 30 wt% SCFS, while the GB@rGO contents altered from 0 to 6 wt% to investigate its effect on thermal conductivity enhancement. The λ of SCF(30 wt%)/GB@rGO(1 wt%)/PDMS composite with 0.1-mm thickness can reach 23.415 W/m·K, which is 85.72 times higher than pure PDMS. In addition, the PDMS composites also have superior electrical conductivity (1330 S/m) and excellent mechanical properties (~ 90% elongation at break, and bend, twist, fold available). In the TIM tests, compared with commercial thermal grease, our composite sample presented obviously higher heat transfer capacity. Overall, our PDMS composites are of great prospect as a flexible TIM with ultrahigh thermal conductivity for the highly efficient elimination of heat from electronic equipment.Graphical abstractSCF/GB@rGO/PDMS composites with excellent thermal conductivity and superior mechanical flexibility were prepared by spatial confining forced network assembly.