Multi‐contact hybrid thermal conductive filler Al2O3@AgNPs optimized three‐dimensional thermal network for flexible thermal interface materials

Abstract

AbstractIn this work, a multi‐contact Al2O3@AgNPs hybrid thermal conductive filler was synthesized by in‐situ growth method to fill high thermal conductivity polydimethylsiloxane (PDMS)‐based composites to prepare TIMs. And the thermal conductivity, electrical conductivity, and mechanical properties of the composite materials were studied. During the synthesis process of the multi‐contact hybrid filler, different concentrations of silver ions were reduced to generate silver nanoparticles and attached to the surface of Al2O3. Al2O3@AgNPs/PDMS thermally conductive composites were prepared by changing the filler addition. Using SEM, XPS, and XRD is used to characterize the morphology and chemical composition of Al2O3@AgNPs hybrid filler. The thermal conductivity of PDMS‐based composites with different AgNPs content under 70 wt% filler loading was studied. The results show that the thermal conductivity of PDMS‐based composites filled with 7owt%Al2O3@3AgNPs/PDMS multi‐contact hybrid filler is 0.67 W/m·K, which is 3.72 times that of pure PDMS, and is higher than that of unmodified Al2O3 with the same addition amount. /PDMS composite material has a high thermal conductivity of 24%. This work provides a new idea for the design and manufacture of high thermal conductivity hybrid fillers for TIMs.