Subtitle
Nothing stuck to Mafia boss John Gotti, who evaded justice for years by bribing and threatening jurors and witnesses.
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That earned him the name the Teflon Don, after one of the slipperiest material on earth.
Teflon was in the spacesuits the Apollo crew wore for the moon landed in pipes and valves used in the Manhattan Project,
and maybe in your kitchen as the nonstick coating on frying pans and cookie sheets.
So, what is this slippery solid, and why doesn't anything stick to it?
Teflon is the brand name for polytetrafluoroethylene or PTFE.
It was stumbles upon accidentally in 1938 by a 27-year-old American chemist named Roy Plunkett.
while he was tring to develop a non-toxic refrigerant fluid for DuPont, a chemical company.
The strange, white substance that formed inside his lab canister was chemically inert, meaning it wouldn't react with other substances.
It also hand an extremely low coefficient of friction, making other materials slide right off it.
Teflon's properties make it perfect when you need something slippery, chemical resistant, or waterproof, which means it has a lot of applications.
It can be found all over the place, as a coating on raincoats, industrial ball bearings, artificial joints, circuit boards, and even the Rocky Mountains-themed roof of the Denver International Airport.
The incredible properties of PTFE come from its molecular structure.
It's a polymer, meaning it's made of long chains of repeating unit of atoms strung together.
A PTFE chain has a backbone of carbon atoms, each of which is attached to two fluorines.
The fluorine atoms surround the carbon like armor, spiraling around the chain, and the bond between
carbon and fluorine is incredibly tight.
Like a couple that ignores everyone except each other, carbon and fluorine interact so strongly that the normal, intermolecular force that help substances stick to each other, don't stand a chance.
Even the famously adhesive feet of geckos usually can get a grip.
One method involves sandblasting the pan, or etching it with chemicals to make it rough.
Then, a special primer is applied, which acts like glue.
Its exact composition is a trade secret guarded by each manufacturer.
The pan is sprayed with liquid PTFE and heated to around 800 degree Fahrenheit.
The layers then solidify into a smooth, stick coating.
When you later cook eggs in this PTFE-coated pan, the extra tight carbon-fluorine bonds just ignore
the water and fat and protein molecules int he eggs.
Without those interations, the food just slides around without sticking.
You might wonder if it's safe to cook in a PTFE-coated pan. The answer is yes, if you're careful.
PTFE is stable at moderate tempertatures, like you'd use to cook eggs or fish, but above 500 degrees Fahrenheit, it start to degrade, and hearing it further releases fumes that can make you feel sick.
an empty pan can reach 500 degrees fast over high heat, but most kitchens are ventilated well enough to dissipate the fumes.
People used to also think that accidentally consuming PTFE, that flaked off a scratched pan was bad for you.
but the current consensus is that it's harmless.
Because PTFE doesn't interact with other chemicals very well, it isn't thought to break down inside your body.
Whether it's safe to manufacture Teflon is another story.
DuPont and its spin-off company Chemours, now face lawsuits worth millions of dollars.
They've been accused of polluting the environment for decades and exposing employees and local communities to health risks associated with toxic chemical called PFOA.
That chemical was involved in manufacturing Teflon.
As for John Gotti, in 1992, the Mob boss was finally convict of five counts of murder, among other charges.
That prompted the head of the FBI office in New York City to announce, "The Teflon is gone. The don is covered in Velcro, and all the charges stuck."
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