Coefficient of Friction of Rubber

Manufacturer: We are new manufacturer of car wipers and brake pads. Please let us know about friction property of rubber and how best to test it.


John Woon (Senior Latex Consultant): Frictional properties of rubber are critical in applications such as tires, shoe soles, wiper blades, brake pads, etc.



The Coefficient of Friction is the amount of force one object must overcome to move over another object. There are two types of friction, namely, “Static Friction” and “Kinetic Friction”.

Static friction is the friction between the surfaces of two objects that are stationary. The irregular surfaces and/or softness of the two objects interlock resulting in frictional force which prevents movement until, at a specific tilting angle or when just sufficient driving force triggers the movement.  This point of movement is the Coefficient of Static Friction.

Kinetic friction applies when two objects are moving relative to each other, rubbing together. When the applied force (i.e. driving force) is greater than the frictional force, movement is initiated at constant velocity. The coefficient of friction involved is called the Coefficient of Kinetic Friction.

The Coefficient of Kinetic Friction is less than the Coefficient of Static Friction for the same materials.

In one typical test, a “sled” is dragged against the surface of a rubber sheet. The normal force between the surfaces is created by the weight of the sled. The sliding resistance or force is measured using the load cell of a tensometer that pulls the sled via a simple pulley arrangement. 

Go to the following link for the video on how Coefficient of Friction of rubber is tested:

https://tinyurl.com/yblm5xry or http://bit.ly/2sQaOIT