Layth Hendow, 15, Hull Collegiate School
Yorkshire.
Molecule of the month: Polytetrafluroethylene
[Teflon]
What is Teflon?
Polytetrafluroethylene, or
better known as Teflon, is a synthetic fluoropolymer. A synthetic fluoropolymer
is a fluorocarbon based polymer with multiple strong carbon-fluorine bonds,
making it high resistant to solvents, acids and bases. http://en.wikipedia.org/wiki/Teflon
Carbon is black,
Fluorine Is green 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. http://inventors.about.com/library/inventors/blteflon.htm
Roy Plunkett
The science behind Teflon
Teflon’s amazing properties are down to its
structure. Like most polymers, Teflon has a carbon based chain however
surrounding the weak carbon chain are fluorine atoms that have strong bonds with the carbon Teflon
structure
which strengthen the whole
structure and gives it its great properties.
How Teflon’s made
In mass production of Teflon, a carcinogen called PFOA (perfluorooctanoic
acid) acts as a catalyst however is very dangerous. But DuPont, the
manufacturers of Teflon, clam there is no PFOA in the finish produce after $300
million lawsuit in 2004. http://inventors.about.com/library/inventors/blteflon.htm
Properties and appliances
Teflon has lots of amazing properties due to its strong carbon- fluorine
bonds. With a friction coefficient of ≤ 0.1, Teflon has the second lowest
friction coefficient; first is a diamond like carbon called DLC, which makes it
perfect for non slip equipment e.g. pans. DuPont invented the non slip pan with
Teflon in 1956 Teflon pan and have manufactured it since and theses pans
are so slippery, it’s the only material that a gecko cannot stick too.
Also Teflon has a very melting point at 327 °C so it won’t melt under the
heat of cooking.
Apart
from cooking, Teflon has other uses in other industries. In cars, the slipperiness
can be used where sliding is used so gears and side plates use Teflon.
Tread
seal tape or Teflon tape is used for electrical cables. Because Teflon is a
very good electrical insulator so the tape can be used to cover exposed wires
or broken wires.
Teflon
gears http://en.wikipedia.org/wiki/Teflon
Teflon tape
Other non stick polymers
Another non stick polymer that is like Teflon, but is more easily
formed, is softer and has a lower melting point (260 °C) is FEP, fluorinated
ethylene propylene. FEP was invented by DuPont like Teflon and is a copolymer
of Teflon. It has similar properties however it has a lower melting point 260
°C so it can’t be used in cooking. However because it softer and is inert
like Teflon, it can be used in electrical business as a putty to fill
wires. http://en.wikipedia.org/wiki/Fluorinated_ethylene_propylene
FEP wire putty
References
http://www2.dupont.com/Teflon/en_US/index.html
http://news.bbc.co.uk/1/hi/magazine/3697324.stm
http://www.wisegeek.com/what-is-teflon.htm
http://www.noquarterusa.net/blog/2008/04/21/the-two-uses-for-teflon/