1 School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China 2 Institute of Modern Industrial Technology of SCUT in Zhongshan, Zhongshan 528400, Guangdong, China 3 School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China
With the development of technology, the amount of heat generated by electronic components has increased significantly. Therefore, it is increasingly urgent to develop materials with high thermal conductivity and high insulation properties. Thermally conductive composites were prepared by mechanical blending using methyl vinyl silicone rubber (SR) as the matrix, and some particles including carbon nanotubes (CNTs), hexagonal boron nitride (BN) and aluminum nitride (AlN) as thermally conductive fillers. The effect of hybridization of three kinds of fillers on the thermal conductivity, electrical insulation and mechanical properties of the composites was studied. The influence of the filler orientation on the thermal conductivity of the composites was investigated. The effect of the heating time on the surface temperature of the composites was also investigated and the theoretical thermal conductivity of the composites was fitted according to Agari model. The composites were characterized by an infrared thermal image, scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The results show that with the decreased addition of AlN and the increased loadings of BN and CNTs, the thermal conductivity of the composites is gradually increased. When the content of AlN, BN and CNTs is 80, 68 phr and 2 phr respectively, the composites show better overall performance, where the out-plane and in-plane thermal conductivity of the composites is 1.857 W·m-1·K-1 and 2.853 W·m-1·K-1, and the volume resistivity and the tensile strength is 2.18×1012 Ω·cm and 4.3 MPa, respectively.
SONG N , CUI S Q , JIAO D J , et al. Influence of hybrid fillers on thermal conductivity of nylon-6/graphene composite[J]. Journal of Materials Engineering, 2018, 46 (3): 28- 33.
YANG X , LIANG C , MA T , et al. A review on thermally conductive polymeric composites: classification, measurement, model and equations, mechanism and fabrication methods[J]. Advanced Composites and Hybrid Materials, 2018, 1 (2): 207- 230.
LI J , LI F , ZHAO X , et al. Jelly-inspired construction of the three-dimensional interconnected BN network for lightweight, thermally conductive, and electrically insulating rubber composites[J]. ACS Applied Electronic Materials, 2020, 2 (6): 1661- 1669.
GUO B , TANG Z , ZHANG L . Transport performance in novel elastomer nanocomposites: mechanism, design and control[J]. Progress in Polymer Science, 2016, 61, 29- 66.
CHEN C , XUE Y , LI X , et al. High-performance epoxy/binary spherical alumina composite as underfill material for electronic packaging[J]. Composites: Part A, 2019, 118, 67- 74.
HU J , HUANG Y , ZENG X , et al. Polymer composite with enhanced thermal conductivity and mechanical strength through orientation manipulating of BN[J]. Composites Science and Technology, 2018, 160, 127- 137.
LI C , LIU B , GAO Z , et al. Electrically insulating ZnOs/ZnOw/silicone rubber nanocomposites with enhanced thermal conductivity and mechanical properties[J]. Journal of Applied Polymer Science, 2018, 135 (27): 46454.
XUE Y , LI X , WANG H , et al. Thermal conductivity improvement in electrically insulating silicone rubber composites by the construction of hybrid three-dimensional filler networks with boron nitride and carbon nanotubes[J]. Journal of Applied Polymer Science, 2019, 136 (2): 46929.
TANG X , GUO Y , LIAO Z , et al. Synergistic enhancement of thermal conductivity between SiCw and h-BN in MVQ-based composite[J]. Fullerenes, Nanotubes and Carbon Nanostructures, 2019, 27 (5): 434- 439.
KUO C F J , CHEN J B , CHEN P Y , et al. Preparation of boron nitride nanosheets using a chemical exfoliation method as a thermal conductive filler for the development of silicone thermal composites part Ⅰ: effect of single- and hybrid-filler additions on the silicone composite performance[J]. Textile Research Journal, 2019, 90 (5/6): 666- 684.
SUN N , SUN J , ZENG X , et al. Hot-pressing induced orientation of boron nitride in polycarbonate composites with enhanced thermal conductivity[J]. Composites: Part A, 2018, 110, 45- 52.
YUAN C , DUAN B , LI L , et al. Thermal conductivity of polymer-based composites with magnetic aligned hexagonal boron nitride platelets[J]. ACS Appl Mater Interfaces, 2015, 7 (23): 13000- 13006.
SHEN H , CAI C , GUO J , et al. Fabrication of oriented hBN scaffolds for thermal interface materials[J]. RSC Advances, 2016, 6 (20): 16489- 16494.
AGARI Y , UEDA A , NEGAI S . Thermal conductivity of a polymer composite[J]. Journal of Applied Polymer Science, 1993, 49 (9): 1625- 1634.
CHEN H , GINZBURG V V , YANG J , et al. Thermal conductivity of polymer-based composites: fundamentals and applications[J]. Progress in Polymer Science, 2016, 59, 41- 85.
LI J , ZHAO X , ZHANG Z , et al. Construction of interconnected Al2O3 doped rGO network in natural rubber nanocomposites to achieve significant thermal conductivity and mechanical strength enhancement[J]. Composites Science and Technology, 2020, 186, 107930.
KUO C F J , DEWANGGA G R S , CHEN J B . Fabrication of a thermally conductive silicone composite by incorporating surface-modified boron nitride[J]. Textile Research Journal, 2018, 89 (13): 2637- 2647.
WANG Y , QIU X , ZHENG J . Study the mechanism that carbon nanotubes improve thermal stability of polymer composites: an ingenious design idea with coating silica on CNTs and valuable in engineering applications[J]. Composites Science and Technology, 2018, 167, 529- 538.