Aerospace insulation is the best thing since
sliced bread.
And soon it might be made from sliced bread.
A group of researchers at the Harbin Institute
of Technology in China have published a paper
in Applied Materials and Interfaces demonstrating
a new way to make carbon foam. It involves
subjecting freshly baked bread to pyrolysis,
which is when you heat a substance up to intense
levels in a chamber with no oxygen. So what
exactly is carbon foam? In general, it’s
a lightweight material made up of almost pure
carbon and is extremely porous. There are
two broad categories: graphitic and non-graphitic.
Each type has its own properties. Graphitic
carbon foams are highly conductive, both for
electricity and thermal energy, also known
as heat. Non-graphitic carbon foams have greater
mechanical strength than their graphitic counterparts.
And they act as thermal insulators -- heat
doesn’t pass through them easily. Both types
are chemically inert. Dr. Yibin Li, head of
the research lab, realized that bread has
the right structure to produce non-graphitic
carbon foam. Like the foam, bread has open
pores. And so his team subjected freshly baked
bread to pyrolysis. As a bread aficionado,
this makes me sad. But it’s all in the name
of science! The team heated the bread to more
than 500 degrees Celsius. That’s 932 degrees
Fahrenheit. Without oxygen to allow the bread
to catch fire, the material carbonized. The
result was a lightweight, strong material
with thermal insulation properties. The big
breakthrough here is that bread isn’t expensive
to manufacture. Typically, scientists must
first manufacture one type of foam and subject
it to pyrolysis to make carbon foam. Some
of these carbon foam precursors are expensive
to produce. But bread doesn’t cost a lot
of, uh, bread. And what can you do with this
carbon foam stuff once you make it? Well,
it’s lightweight, relatively strong, fire
resistant and a thermal insulator. Sounds
like it would be right at home in the aerospace
industry, where you need superior thermal
insulation that can withstand the stresses
of a launch. And if you’re going to to send
stuff up into space, you want it to be lightweight.
So let us toast these scientists for their
discovery! Their work might help us out of
a jam. Even the upper crust should tip their
hats to... my crew is starting to give me
threatening looks so I’ll wrap up.
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