Naked Science Forum

General Science => Question of the Week => Topic started by: Adam Murphy on 02/08/2018 10:34:28

Title: QotW - 18.08.02 - Why are non-stick pans non-stick?
Post by: Adam Murphy on 02/08/2018 10:34:28
Martin asked us:

What’s the science behind non-stick pans? What prevents the sticking?

Any thoughts?
Title: Re: QotW - 18.08.02 - Why are non-stick pans non-stick?
Post by: Tomassci on 02/08/2018 15:47:07
One word: teflon. Teflon is an polymer, which does not like to bond with other chemicals. It looks like this: (https://upload.wikimedia.org/wikipedia/commons/e/eb/Perfluorodecyl-chain-from-xtal-Mercury-3D-balls.png)

The yellow thing is fluorine. It sticks to black balls-carbon-, so it does not stick to other atoms.
Title: Re: QotW - 18.08.02 - Why are non-stick pans non-stick?
Post by: chris on 03/08/2018 09:56:29
We interviewed Ullrich Steiner about non-stick surfaces, superhydrophobicity and Teflon (https://www.thenakedscientists.com/articles/interviews/super-non-stick-surfaces) about 10 years ago.

He did an amazing demo in the studio with a spoon he's treated with the surface coating he had developed. He dropped a droplet of water onto the spoon, which was held at an angle and the water literally leapt off. I remember it vividly to this day!

You can listen to the interview here: https://www.thenakedscientists.com/sites/default/files/media/Naked_Scientists_Show_07.09.30_423_1.mp3
Title: Re: QotW - 18.08.02 - Why are non-stick pans non-stick?
Post by: Adam Murphy on 09/08/2018 12:22:13
This question has now been answered! You can listen to it here: https://www.thenakedscientists.com/podcasts/question-week/how-do-non-stick-pans-work
Title: Re: QotW - 18.08.02 - Why are non-stick pans non-stick?
Post by: wolfekeeper on 11/08/2018 17:51:43
On a related note, one interesting thing I found in my travels- linoleum (polymerised linoleic fatty acids) can approach the slipperiness of PTFE but only when wet or oiled. I think that's why chefs often 'prove' pans- it polymerises the oils and forms a very slippery linoleum-like layer:

https://physics.info/friction/

(Note flooring called 'linoleum' these days is nearly always actually PVC, specifically because linoleum is too slippery when wet.)
Title: Re: QotW - 18.08.02 - Why are non-stick pans non-stick?
Post by: Monox D. I-Fly on 18/01/2020 05:50:46
One word: teflon. Teflon is an polymer, which does not like to bond with other chemicals. It looks like this: (https://upload.wikimedia.org/wikipedia/commons/e/eb/Perfluorodecyl-chain-from-xtal-Mercury-3D-balls.png)

The yellow thing is fluorine. It sticks to black balls-carbon-, so it does not stick to other atoms.
So, if we put a food which contains carbon, like a burnt chicken, it will stick?
Title: Re: QotW - 18.08.02 - Why are non-stick pans non-stick?
Post by: evan_au on 18/01/2020 06:33:19
There have been health concerns raised about much shorter-chain fluorinated carbon molecules.

Some of these have been used in airports for flame-retardent sprays for avgas fires, resulting in high levels of exposure by firemen. The water-soluble end to the chain would make it more dangerous to living organisms.
See: https://en.wikipedia.org/wiki/Perfluorooctanesulfonic_acid
https://en.wikipedia.org/wiki/Perfluorooctanoic_acid