Thermally Stable Dry Adhesive Using Soft Nanocomposite with High Pull-off Strength at High Temperature

Abstract

Bioinspired dry adhesives with protruding tips offer strong, repeatable, and reversible adhesion both in normal and shear directions owing to the presence of a thin spatulate layer. However, the temperature range in which they can be used is limited because most of them are made of polymeric materials that have inherently poor thermomechanical stability. Here, we report a nanocomposite dry adhesive as a high-temperature reversible adhesive with high pull-off strength. The nanocomposite dry adhesive is fabricated by a replica-molding technique with polydimethylsiloxane (PDMS) enforced with multiwalled carbon nanotubes (MWCNTs) of different concentrations. The MWCNT/PDMS composite adhesives exhibit remarkably better thermal stability than pristine PDMS adhesives owing to the excellent thermal and mechanical properties of the MWCNTs in the composite. Furthermore, the nanocomposite adhesives have a high adhesion strength even when they are thermally annealed at high temperatures of up to 350°C, demonstrating a strong potential as a versatile high-temperature reversible adhesive.