Thursday, September 20, 2012

How does Teflon provide reduced friction?

Teflon is most commonly known for its non-stick coatings in frying pans and other cookwares. It is an essential part of most of the kitchens. If you want to cook something (especially without gravy) and you are working with a non-stick pan, there are chances that some of the food will stick to it and will be tough to remove. In comparison, Teflon coated cookware (such as a frying pan) will be very easy to work with. This is because of a very low coefficient of friction.


In fact, Teflon has the third lowest coefficient of friction (= 0.05-0.1) among the known solid materials. It is a hydrophobic and lipophobic material, which means, neither water nor oil sticks to it, thus making cooking easier. There are a number of factors which provide low coefficient of friction to Teflon. It exhibits high cohesive forces, but extremely low adhesive forces, which makes it difficult for anything to attach to the Teflon surface. 


Teflon has the chemical name of polytetrafluoroethylene (or PTFE). It is a polymer composed of carbon and fluorine atoms. Fluorine is very electronegative and does not part with its electrons. It does not form hydrogen bonds either. This causes extremely low Van der Waals forces and hence other substances find it difficult to stick to it.


And that is how Teflon (or PTFE) provides surface of low friction.


Hope this helps. 

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