WEBVTT

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Nothing stuck to Mafia boss John Gotti

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who evaded justice for years by bribing
and threatening jurors and witnesses.

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That earned him the name
the Teflon Don

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after one of the slipperiest 
materials on Earth.

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Teflon was in the spacesuits the Apollo
crew wore for the moon landing,

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in pipes and valves used 
in the Manhattan Project,

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and maybe in your kitchen as the nonstick
coating on frying pans and cookie sheets.

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So what is this slippery solid,
and why doesn't anything stick to it?

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Teflon is a brand name for
polytetrafluoroethylene,

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or PTFE.

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It was stumbled upon accidentally in 1938
by a 27-year-old American chemist

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named Roy Plunkett

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while he was trying to develop 
a non-toxic refrigerant fluid for DuPont,

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a chemicals company.

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The strange, white substance that formed
inside his lab canister

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was chemically inert,

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meaning it wouldn't react 
with other substances.

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It also had an extremely 
low coefficient of friction,

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making other materials slide right off it.

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Teflon's properties make it perfect
when you need something slippery,

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chemical resistant,

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or waterproof,

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which means it has a lot of applications.

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It can be found all over the place,

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as a coating on raincoats,

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industrial ball bearings,

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artificial joints,

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circuit boards,

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and even the Rocky Mountains-themed roof
of the Denver International Airport.

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The incredible properties of PTFE
come from its molecular structure.

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It's a polymer,

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meaning it's made of long chains of
repeating units of atoms strung together.

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A PTFE chain has a backbone 
of carbon atoms,

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each of which is attached 
to two fluorines.

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The fluorine atoms surround the carbon
like armor,

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spiraling around the chain,

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and the bond between carbon and fluorine
is incredibly tight.

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Like a couple that ignores everyone
except each other,

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carbon and fluorine interact so strongly

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that the normal, intermolecular forces
that help substances stick to each other

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don't stand a chance.

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Even the famously adhesive feet of geckos
usually can't get a grip.

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But wait!

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If PTFE doesn't stick to anything,

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how can it be so firmly attached
to something like a pan?

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One method involves sandblasting the pan

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or etching it with chemicals 
to make it rough.

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Then, a special primer is applied,
which acts like glue.

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Its exact composition is a trade secret
guarded by each manufacturer.

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The pan is sprayed with liquid PTFE

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and heated to around 
800 degrees Fahrenheit.

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The layers then solidify into
a smooth, slick coating.

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When you later cook eggs
in this PTFE-coated pan,

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the extra tight carbon-fluorine bonds

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just ignore the water and fat and protein
molecules in the eggs.

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Without those interactions,

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the food just slides around 
without sticking.

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You might wonder if it's safe to cook
in a PTFE-coated pan.

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The answer is yes, if you're careful.

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PTFE is stable at moderate temperatures,
like you'd use to cook eggs or fish,

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but above 500 degrees Fahrenheit,
it starts to degrade,

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and heating it further releases fumes
that can make you feel sick.

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An empty pan can reach 500 degrees fast
over high heat,

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but most kitchens are ventilated 
well enough to dissipate the fumes.

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People used to also think 
that accidentally consuming PTFE

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that flaked off a scratched pan
was bad for you,

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but the current consensus 
is that it's harmless.

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Because PTFE doesn't interact with other
chemicals very well,

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it isn't thought to break down
inside your body.

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Whether it's safe to manufacture Teflon
is another story.

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DuPont and its spin-off company Chemours

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now face lawsuits 
worth millions of dollars.

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They've been accused of polluting
the environment for decades

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and exposing employees 
and local communities

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to health risks associated 
with a toxic chemical called PFOA.

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That chemical was involved
in manufacturing Teflon.

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As for John Gotti,

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in 1992, the Mob boss was finally 
convicted of five counts of murder,

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among other charges.

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That prompted the head of the FBI office
in New York City to announce,

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"The Teflon is gone.

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The don is covered in Velcro,
and all the charges stuck."