Efficiently Controlling the 3D Thermal Conductivity of a Polymer Nanocomposite via a Hyperelastic Double‐Continuous Network of Graphene and Sponge

Abstract

Graphene‐reinforced polymer composites with high thermal conductivity show attractive prospects as thermal transfer materials in many applications such as intelligent robotic skin. However, for the most reported composites, precise control of the thermal conductivity is not easily achieved, and the improvement efficiency is usually low. To effectively control the 3D thermal conductivity of graphene‐reinforced polymer nanocomposites, a hyperelastic double‐continuous network of graphene and sponge is developed. The structure (orientation, density) and thermal conductivity (in‐plane, cross‐plane) of the resulting composites can be effectively controlled by adjusting the preparation and deformation parameters (unidirectional, multidirectional) of the network. Based on the experimental and theoretical simulation results, the thermal conduction mechanism is summarized as a two‐stage transmission of phonons. The in‐plane thermal conductivity increases from 0.175 to 1.68 W m−1 K−1 when the directional compression ratio increases from 0% to 95%, and the corresponding enhancement efficiency exceeds 300. The 3D thermal conductivity reaches a maximum of 2.19 W m−1 K−1 when the compression ratio is 70% in three directions, and the graphene content is 4.82 wt%. Moreover, the thermal conduction network can be largely prepared by power‐driven roller equipment, making the composite an ideal candidate for sensitive robotic skin for temperature detection.

Highly compressible and anisotropic lamellar ceramic sponges with superior thermal insulation and acoustic absorption performances

“…n recent years, various sponge-like materials, including carbon nanotube aerogels 1,2 , biomass-derived aerogels [3][4][5][6] , graphene aerogels [7][8][9][10][11][12] , ceramic nanofiber aerogels [13][14][15] , and carbon nanofiber aerogels [16][17][18] , have received significant interest owing to their high compressibility and resilience under large deformation, which results from their porous three-dimensional network structures. Among them, ceramic sponge materials have attracted more interest owing to their lightweight feature, high specific surface area, low thermal conductivity, and excellent chemical and thermal stability 13,14,19,20 .…”

High Intrinsic Thermal Conductivity of Polythiophene by Reducing Steric Hindrance and Enhancing p‐π Conjugation

“…In order to improve the thermal conductivity, researchers have made many studies. Currently, most heat dissipation material is based on ceramic, [1][2][3][4] metal, [5][6][7][8][9][10][11] and carbonbased [12][13][14][15][16][17] fillers. Due to its shortcomings such as high price, difficult processing, and poor mechanical properties, exploring high intrinsic thermally conductive polymers has become more attractive.…”

Enhancing thermal conductivity of polyimide composite film by electrostatic self-assembly and two-step synergism of Al2O3 microspheres and BN nanosheets

“…The rst is to design new thermally conductive llers, such as awless graphene, 13 exfoliated BN nanosheet (BNNS) 14 and BN nanotubes. 15 The second is to construct a three-dimensional thermally conductive network by a novel method, such as electrostatic spinning, 16 chemical vapor deposition (CVD), 17 template method, [18][19][20] freeze-drying method, 21 and segregated structure method. 22 The third is to decrease the thermal resistance at the heat conduction interface, mainly by increasing the compatibility of the interface 23 and reducing the interface scattering of phonons.…”