BBC Crowdscience: The Physics of Stickiness

Welcome to Physics 6th October 2020

Physicist Dr Ivan Vera Marun helps the BBC find out why things stick together, and the surprising link between geckos and graphene.

This week, BBC Radio’s CrowdScience looked into a listener question about why things stick together. Obviously they came to Physics at Manchester for some answers: famously, graphene was created here by carefully separating layers of pencil graphite with sticky tape (that’s why Professor Andre Geim’s tape dispenser is in the Museum of Science & Industry.)

Before they could get to the cutting edge of advanced materials, though, the presenters found out about how Neanderthals invented glue and how the structure of geckos’ feet allows them to walk up walls.

It was all fascinating stuff, but how does it work? One of the experts on hand to help the presenter get to grips (…sorry) with the science of stickiness was Dr Ivan Vera Marun, who’s a lecturer in Condensed Matter Physics in our department. He told the story behind the discovery of graphene and explained how it’s Van der Waals forces between surfaces cause things to stick together – including geckos and ceilings.

In fact, materials scientists are taking inspiration from the gecko to make new kinds of robots.

Ivan explains: “One application of van der Waals forces that is inspired from nature, is the replication of gecko’s stickiness in small robots that can climb walls or easily grip objects.

“Here, engineers develop artificial membranes with arrays of microfibers modelled on gecko’s toes, which form part of the ‘feet and hands’ of the robot. This is an active line of research and development that enables robots to perform advanced skills like handling complex objects with the right combination of force and delicacy.”

Find out more

You can listen to the show on the BBC’s website – it’s also available on BBC Sounds or wherever you get your podcasts (look for CrowdScience episode #204, ‘What makes stuff sticky?’)

Read more about climbing robots with this article from Science: Gecko-inspired gripper could help robots climb walls

Gecko image by Rudy and Peter Skitterians and sticky notes header image by Monfocus, both from Pixabay