Researchers at Tsinghua University in Beijing have developed a new nanomaterial adhesive tape that can function over a wide range of temperatures. Unlike standard sticky tapes, which are prone to losing their stickiness and also leave a residue, this ultrathin, ultra-lightweight and flexible tape made from carbon nanotubes remains adhesive even in extreme temperatures and is easy to remove.
As reported in the journal Nano Letters [Jin et al. Nano Lett. (2019) DOI: 10.1021/acs.nanolett.9b01629], the team wanted to explore the possibility of devising a new kind of sticky tape made up of superaligned carbon nanotube (SACNT) films, nanotubes that are precisely aligned parallel to each other and which can be formed into very thin yet strong yarns or films. To produce the tape, the scientists pulled a film from the interior of an array of SACNTs in the same way as pulling tape from a dispenser, with the resulting double-sided tape able to stick to surfaces through van der Waals interactions, weak electric forces produced between two atoms or molecules when close together.
The SACNT tape, which demonstrated improved performance over standard adhesives at temperatures between –196C and 1,035C, is very sticky, super clean and multi-purpose, and can be made comparatively cheaply in large amounts. The tape can be removed even after exposure to extreme temperature just by peeling it off, soaking it in acetone or burning it, leaving little residue, and can adhere to a range of different materials, although it stuck more strongly to smooth surfaces in the same way as conventional tape.
Previous research has examined the use of nanomaterials, including vertically aligned multi-walled carbon nanotubes, to produce improved sticky tape. While these are stronger than traditional sticky tape at extremes of temperature, they tend to be quite thick and not cost-effective for production in large amounts. The researchers began their interest in adhesion when looking to understand the role of gravity during the growth of super-long carbon nanotubes in kite-flying mode, for which they needed an adhesive that could operate at a temperature of over 900C. They found the SACNT film ideal for their purposes, inspiring them to explore the adhesive capability and mechanism of the films.
The SACNT tape could find uses in mechanical and electrical bonding, and thermal dissipation in electronic devices, as well as in electronic components that become heated up in use. In extremely high- or low-temperature environments, the tape could be useful for devices in aerospace engine shells, satellite, or even in space exploration. However, there is still much room to further improve the adhesion strength of the tapes by at least one to two orders of magnitude, and the team also now hope to develop composite SACNT tapes to further improve its adhesion capability.