Electrothermal actuation and release of adhesiveness of conductive carbon nanotube/epoxy composites by Joule heating

Abstract

The effect of an embedded electro-conductive multi-walled carbon nanotube (MWCNT) nanopaper in an epoxy matrix on the release of the frozen actuation force and the actuation torque in the carbon nanotube nanopaper/epoxy composite after heating above its glass transition temperature is assessed. The presence of the nanopaper augments the recovery of the actuation stress by the factor of two in comparison with the pure epoxy strip. The strengthening of the composite is attributed to the interlocking of the carbon nanotubes with the epoxy. Moreover, the internally heated electro-conductive carbon nanotube nanopaper/epoxy composite not only substantially shortens curing time while retaining comparable strength of the adhesive bonding of the steel surfaces but also enables a release of such bonds by repeated application of DC current.