Dry glue is an

adhesion Adhesion is the tendency of dissimilar particles or interface (matter), surfaces to cling to one another. (Cohesion (chemistry), Cohesion refers to the tendency of similar or identical particles and surfaces to cling to one another.) The ...

product based upon the

adaptation In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the p ...

s of

gecko Geckos are small, mostly carnivorous lizards that have a wide distribution, found on every continent except Antarctica. Belonging to the infraorder Gekkota, geckos are found in warm climates. They range from . Geckos are unique among lizards ...

s' feet that allow them to climb sheer surfaces such as vertical glass. Synthetic equivalents use

carbon nanotube A carbon nanotube (CNT) is a tube made of carbon with a diameter in the nanometre range ( nanoscale). They are one of the allotropes of carbon. Two broad classes of carbon nanotubes are recognized: * ''Single-walled carbon nanotubes'' (''S ...

s as

synthetic setae Synthetic setae emulate the setae found on the gecko feet, toes of a gecko and scientific research in this area is driven towards the development of Dry glue, dry adhesives. Geckos have no difficulty mastering vertical walls and are apparently cap ...

on reusable adhesive patches.

Background

A gecko can hang on a glass surface using only one toe. This ability is attributed to

van der Waals force In molecular physics and chemistry, the van der Waals force (sometimes van der Waals' force) is a distance-dependent interaction between atoms or molecules. Unlike ionic or covalent bonds, these attractions do not result from a chemical elec ...

, although a more recent study suggests that water molecules of roughly monolayer thickness (present on virtually all natural surfaces) also play a role.

Developments

In 2007, researchers from the

University of Akron The University of Akron is a public university, public research university in Akron, Ohio, United States. It is part of the University System of Ohio. As a STEM fields, STEM-focused institution, it focuses on industries such as polymers, advance ...

and

Rensselaer Polytechnic Institute Rensselaer Polytechnic Institute (; RPI) is a private university, private research university in Troy, New York, United States. It is the oldest technological university in the English-speaking world and the Western Hemisphere. It was establishe ...

announced they had developed a form of flexible, reusable gecko tape using

s to create microscopic

and

spatula A spatula is a broad, flat, flexible blade used to mix, spread and lift material including foods, drugs, plaster and paints. In medical applications, "spatula" may also be used synonymously with tongue depressor. The word ''spatula'' derives ...

e capable of supporting a

shear stress Shear stress (often denoted by , Greek alphabet, Greek: tau) is the component of stress (physics), stress coplanar with a material cross section. It arises from the shear force, the component of force vector parallel to the material cross secti ...

of 32 N/ cm², which is four times the strength of a gecko's foot. In 2008 researchers from the

University of Dayton The University of Dayton (UD) is a Private university, private, Catholic research university in Dayton, Ohio, United States. Founded in 1850 by the Society of Mary (Marianists), Society of Mary, it is one of three Marianist universities in the U ...

reported a gecko glue capable of supporting 100N/cm², ten times the strength generated by a gecko's foot. The research also used carbon nanotubes, but included a curled end which allowed stronger binding but easy removal.

Defense Advanced Research Projects Agency The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military. Originally known as the Adva ...

(DARPA) has a project called "Z-Man" that is attempting to develop a fabric allowing soldiers to scale vertical walls while carrying a full combat load. In February 2012

Nitto Denko is a Japanese company that produces tapes, vinyl, LCDs, insulation, and several other products. It was founded in Osaki, Tokyo in 1918 to produce electrical insulation and it survived World War II, despite the destruction of its central offices ...

developed a version of gecko tape capable of sticking at temperatures between -150 and 500° C.

References

{{Reflist

External links

Semiconductor Adhesives
Adhesives

Background

Developments

See also

References

External links