Enhanced thermal conductivity of epoxy composites via bridged Al₂O₃ network with in situ formed silver nanoparticles

Abstract

It is of great significance to achieve excellent thermal conduction for polymer composites in electrical insulation application. However, traditional polymer composites exhibit limited thermal conduction due to the absence of efficient heat transfer pathways. Herein, Al 2 O 3 microspheres absorbed with silver acetate (AgAc) and 2-ethyl-4-methylimidazole (2E4MI) complex were prepared as fillers for constructing heat transfer paths in epoxy composites. At a suitable temperature, 2E4MI was released from Ag(2E4MI) 2 Ac complex and initiated the curing reaction of epoxy. Simultaneously, nano silver ions were reduced, sintered in situ and then bridged separate Al 2 O 3 microspheres to 3D filler network, which acted as thermal transport pathways in matrix. The thermal conductivity increased from 1.38 W/mK for Al 2 O 3 /epoxy composites to 2.62 W/mK for Al 2 O 3 @Ag(2E4MI) 2 Ac/epoxy composites at 60 vol% Al 2 O 3 loading. Thanks to the 3D filler network, the tensile strength of Al 2 O 3 @Ag(2E4MI) 2 Ac/ epoxy composites was obviously improved. Both the electrical resistivity and dielectric strength of the composites were basically preserved. Al 2 O 3 @Ag(2E4MI) 2 Ac/ epoxy composites exhibit promising application in thermal management materials for advanced electric machinery and electronic devices.

Polymer‐based nanocomposites in semiconductor packaging

“…Therefore, the stress on the solder joint is reduced by 0.1–0.25 times, and the service life is increased by 10–100 times [55]. In addition, it can effectively reduce the mechanical impact of the external environment on the solder joint [56]. Therefore, underfill materials should have the following properties: low viscosity to completely fill the gap between the chip and the substrate, low CTE difference with the solder joint and high Tg to ensure the reliability of semiconductor devices at high temperatures, high thermal conductivity to reduce heat buildup in semiconductor devices, suitable elastic modulus to resist mechanical shock, electrical insulation to avoid short circuits, low dielectric constant, and low dielectric loss to avoid transmission losses of high frequency signals [18].…”

Thermal conductivity controlled by a segregated network prepared using carbon nanotube/polyamide 6 composite with glass bubbles

“…Many applications require enhanced thermal insulation and heat emission. [17][18][19] For instance, aeronautic and require high thermal insulation properties of materials to withstand extremely high-temperature conditions. Construction engineering is one of the application fields that require thermal insulation materials for saving energy.…”

Improving the mechanical properties and curing characteristics of styrene‐butadiene rubber/butadiene rubber composites by incorporating silicon carbide

“…Unfortunately, few research works have been implemented concerning the improvement of SBR/BR mechanical and microstructural properties at the same time, and it has been largely neglected in recent studies. High thermal conductive materials contain carbides such as silicon carbide (SiC) 40 ; nitrides, such as aluminum nitride (AlN) and boron nitride (BN) 41 ; and oxides, such as alumina and silicon dioxide, 42 which can improve the properties of thermoset composites significantly 43 . For example, Sanctuary et al 44 compared isothermal and nonisothermal cures for an epoxy resin‐filled nanoalumina cured with a triamine.…”