Molecule of the Month
Congratulation to 15 year old Year 10 pupil, Layth Hendow, who has written an article about Teflon for Bristol University’s ‘Molecule of the Month’. Layth is one of the few, if not the only person of his age group to have an article accepted for this site.
“At the University of Bristol, every month, university students write a page about a molecule of their choice," says Layth. "This is called Molecule of the Month. However I had a go at writing a page about a molecule (polytetrafluroethylene; Teflon) and it has been accepted by Paul May, Head of Science at the University of Bristol.”
A taster of Layth's article:
What is Teflon?
Polytetrafluoroethylene, better known as Teflon, is a synthetic fluoropolymer. A synthetic fluoropolymer is a fluorocarbon-based polymer with multiple strong carbon-fluorine bonds, making it highly resistant to solvents, acids and bases.
The discovery
Polytetrafluroethylene was discovered by Roy Plunkett, an American chemist from New Carlisle, Ohio in 1938. In an experiment to try and make a new CFC refrigerant, the tetrafluroethylene polymerized with the container it was in to make a white waxy substance called polytetrafluroethylene, later patented in 1941, and then commercially sold as Teflon in 1946.
The science behind Teflon
Teflon is a polymer, which is made by joining together lots of smaller molecules called monomers. In this case, the monomer is tetrafluoroethene (TFE), and when polymerised it becomes poly-TFE, or PTFE as it's sometimes called.
Properties and appliances
Teflon's amazing properties are down to its structure. Like most polymers, Teflon has a carbon-based chain. However, instead of reactive C-H bonds which occur in most polymers, Teflon has all its hydrogens replaced by fluorines. These strong C-F bonds are extremely resistant to attack by any other reagents, making Teflon very inert. This means that no other molecules will react with or stick to Teflon. The exception is Teflon itself, which will stick to itself quite readily, forming thick layers or solid blocks. With a friction coefficient of <0.1, Teflon has the second lowest friction coefficient (surpassed only by diamond-like carbon), which makes it perfect for non-stick items e.g. pans. DuPont invented the non-stick pan coated with Teflon in 1956 and have manufactured it ever since. Teflon coatings are so slippery that they are the only material that a gecko cannot stick too. Also Teflon has a high melting point at 327°C so it won’t melt under the heat of cooking.
If nothing sticks to Teflon, how does Teflon stick to the pan?
To find out, view Layth's article in full:
