Why does rubber have high friction?

Vroom! Tyre manufactures have spent decades trying to find out why rubber is so 'sticky'.

11th March 2017
Why does rubber have high friction? (Getty)

Asked by: Harper X, Dublin

Despite decades of research into the frictional properties of rubber by tyre manufacturers, the precise causes of the ‘stickiness’ of rubber are still the subject of argument. Current theories suggest that when rubber moves over smooth surfaces, it’s the molecular forces between the two that are the main cause of friction. But when the surface is rough, it’s the deformation of entire molecular layers of rubber that’s the chief cause of friction. 


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