Silicone Elastomer Composites Fabricated with MgO and MgO-Multi-Wall Carbon Nanotubes with Improved Thermal Conductivity

Abstract

The effect of multiwall carbon nanotubes (MWCNTs) and magnesium oxide (MgO) on the thermal conductivity of MWCNTs and MgO-reinforced silicone rubber was studied. The increment of thermal conductivity was found to be linear with respect to increased loading of MgO. In order to improve the thermal transportation of phonons 0.3 wt % and 0.5 wt % of MWCNTs were added as filler to MgO-reinforced silicone rubber. The MWCNTs were functionalized by hydrogen peroxide (H2O2) to activate organic groups onto the surface of MWCNTs. These functional groups improved the compatibility and adhesion and act as bridging agents between MWCNTs and silicone elastomer, resulting in the formation of active conductive pathways between MgO and MWCNTs in the silicone elastomer. The surface functionalization was confirmed with XRD and FTIR spectroscopy. Raman spectroscopy confirms the pristine structure of MWCNTs after oxidation with H2O2. The thermal conductivity is improved to 1 W/m·K with the addition of 20 vol% with 0.5 wt % of MWCNTs, which is an ~8-fold increment in comparison to neat elastomer. Improved thermal conductive properties of MgO-MWCNTs elastomer composite will be a potential replacement for conventional thermal interface materials.

Surface Functionalization and Humidity on Charge Transport in PP/TiO2 and PP/MgO Nanocomposites

“…The presence of anatase (tetragonal) TiO2 is indicated by the strong diffraction peaks observed at 25° (101) and 48° (200) [14]. Additionally, the peaks at 36.9° (111), 42.9° (200), and 62.3° (220) indicate the presence of face-centered cubic (FCC) structured MgO nanoparticles [15].…”

In situ generated gas bubble-directed self-assembly of multifunctional MgO-based hybrid foams for highly efficient thermal conduction, microwave absorption, and self-cleaning

“…6d). 2,5,7,9,11,[35][36][37][38][39][40][41][42][43][44][45][46]48 The heat transfer pathway of foams largely depends on their composition. Herein, MgO/Mg(OH) 2 /C foams are composed of MgO, Mg(OH) 2 , and amorphous C; MgO/Co/C foams consist of Co 0 , MgO, and amorphous C. Heat is transferred via electrons in Co 0 and crystal lattice vibrations (phonons) in MgO, Mg(OH) 2 , amorphous C, and pure silica films.…”

Nano and micro co‐filled aluminum nitride/magnesium dihydrate—Silicone rubber composites for high voltage insulation

“…13 In case of nanofillers, several studies involving popular nanofillers such as alumina (Al 2 O 3 ), silica (SiO 2 ), magnesium oxide (MgO), zinc oxide (ZnO), boron nitride (BN), and aluminum nitride (AlN) were conducted. [14][15][16][17][18][19][20][21][22] However, in choice of nanofillers, there often exists a trade-off between electrical insulating properties and thermal conductivity. Electrical resistivity of Al 2 O 3 , SiO 2 (quartz), ZnO, MgO, and BaTiO 3 at ambient conditions was reported to be between 10 12 -10 15 , 23 10 16 -10 18 , 24 10 6 , 25 10 16 , 13 10 7 -10 10 Ω m, 26 respectively.…”

“…In case of nanofillers, several studies involving popular nanofillers such as alumina (Al 2 O 3 ), silica (SiO 2 ), magnesium oxide (MgO), zinc oxide (ZnO), boron nitride (BN), and aluminum nitride (AlN) were conducted 14–22 . However, in choice of nanofillers, there often exists a trade‐off between electrical insulating properties and thermal conductivity.…”