Aerogel Perfusion-Prepared h-BN/CNF Composite Film with Multiple Thermally Conductive Pathways and High Thermal Conductivity

Abstract

Hexagonal boron nitride (h-BN)-based heat-spreading materials have drawn considerable attention in electronic diaphragm and packaging fields because of their high thermal conductivity and desired electrical insulation properties. However, the traditional approach to fabricate thermally conductive composites usually suffers from low thermal conductivity, and cannot meet the requirement of thermal management. In this work, novel h-BN/cellulose-nano fiber (CNF) composite films with excellent thermal conductivity in through plane and electrical insulation properties are fabricated via an innovative process, i.e., the perfusion of h-BN into porous three dimensional (3D) CNF aerogel skeleton to form the h-BN thermally conductive pathways by filling the CNF aerogel voids. When at an h-BN loading of 9.51 vol %, the thermal conductivity of h-BN/CNF aerogel perfusion composite film is 1.488 W·m−1·K−1 at through plane, an increase by 260.3%. The volume resistivity is 3.83 × 1014 Ω·cm, superior to that of synthetic polymer materials (about 109~1013 Ω·cm). Therefore, the resulting h-BN/CNF film is very promising to replace the traditional synthetic polymer materials for a broad spectrum of applications, including the field of electronics.

Nanocellulose Hybrids with Metal Oxides Nanoparticles for Biomedical Applications

“…On the contrary, during acid hydrolysis the amorphous regions of cellulose are attacked and disintegrated resulting rod-like rigid high crystalline CNCs [ 22 ]. AFM images of CNF and CNC celluloses are shown in Figure 1 a,b [ 23 , 24 ].…”

“… AFM images of ( a ) cellulose nanofibrils (CNF) [ 23 ], ( b ) cellulose nanocrystals (CNC) [ 24 ] and ( c ) bacterial cellulose (BC) [ 6 ]. …”

Synergistic Effects of Boron Nitride (BN) Nanosheets and Silver (Ag) Nanoparticles on Thermal Conductivity and Electrical Properties of Epoxy Nanocomposites

“…However, BNNSs are difficult to form a thermal transfer network in polymer matrix alone. If the BNNSs were connected by nanoparticles to form an inter-filler thermal network in polymer composites, the thermal conductivity would be effectively improved at relatively low content [24][25][26]. Silver nanoparticles (AgNPs) are potentially used as the connecting nanoparticles, owing to their outstanding thermal conductivity and simpler distribution on the surface of BNNSs by silver nitrate reduction [27,28].…”

Design of Heat-Conductive hBN–PMMA Composites by Electrostatic Nano-Assembly

“…In the electronics industry, synthetic polymers are commonly used in encapsulation, as well as for packaging materials. However, the synthetic polymeric materials used possess low thermal conductivities of 0.1-0.5 W•m −1 •K −1 [9]. Therefore, the development and improvement of heat-conductive polymeric composite materials are crucial to improve the heat-dissipation of electronic devices.…”

“…Therefore, the development and improvement of heat-conductive polymeric composite materials are crucial to improve the heat-dissipation of electronic devices. Recently, two-dimensional (2D) boron nitride (BN) sheets which possess good thermal conductivity, oxidation resistance, high elastic modulus, and electrical insulation were widely used as 2D micro/nano thermal conductive fillers [9][10][11]. The unique honeycomb-configured sp 2 -bonded boron and nitrogen promotes anisotropic thermal conductivity with in-plane and out-of-plane thermal conductivity of 600 and 30 W•m −1 •K −1 , respectively [12].…”