High thermal conductivity graphene oxide/carbon nanotubes/butyl rubber composites prepared by a dry ice expansion pre‐dispersion flocculation method

Abstract

AbstractButyl rubber (IIR) is widely used in tire inner liners and tubes, vulcanization bladders, and shock absorption materials due to its extremely low air permeability, excellent aging resistance, and good energy absorption. However, its low thermal conductivity affects its performance and the service life of the product, while it also limits its application. Therefore, the preparation of butyl rubber composites with high thermal conductivity is of great significance and practical value. This paper proposes the use of a dry ice expansion pre‐dispersion flocculation method to improve the thermal conductivity of butyl rubber composites by simultaneously doping graphene oxide (GO) and multiwalled carbon nanotube (MWCNTs) in butyl latex. The experimental results of this study show that the dry ice expansion pre‐dispersion method uses the huge volume expansion force of dry ice to break the nanofillers aggregates during sublimation, promote the dispersion of nanofillers, and achieve better modification effects. Moreover, GO and MWCNTs have good synergistic thermal conductivity, which can establish a complete three‐dimensional thermal conductivity network inside the composite. When 5 wt% of GO and 5 wt% of MWCNTs were added, GO/MWCNTs/IIR composites exhibited the highest thermal conductivity, which reached 0.423 W m−1 K−1 at 180°C.