DAISY: Your body is an amazing thing...
You can get scraped, cut, or worse...
the human body has the ability to bounce right back...
other than a little scar tissue, you are as good as new.
NASA is designing organic structural material that has that same ability.
NASA’s self healing material is next...
On Real World. [music]
DAISY: Imagine a military plane flying a dangerous mission.
Just a bit of enemy fire could bring that mission down...
Or think of a space craft, exploring new worlds...
A tiny bit of space debris could cause the crew to
explore ways to stay alive, instead of new frontiers...
But what if there was a way to prevent punctures in airplanes and space craft...
NASA’s looking at a way, not to prevent them, but to fix them, immediately.
By developing a self healing material, in a NASA Lab,
the agency is hoping to negate some of the biggest
dangers of air and space travel.
MIA SIOCHI: The kind of self healing material that we’re looking at is puncture healing.
DAISY: Mia Siochi is the Acting Head for the Advanced Materials
and Processing branch at NASA’s Langley Research Center.
MIA: The way we test it is actually we shoot a bullet through it.
And what we’re looking for is once the bullet penetrates,
that it will close immediately, right back behind it.
What happens is the polymer inherently flows as the bullet penetrates.
And the reason is as the bullet goes in, it actually
raises the temperature around the region where it goes in.
DAISY: Polymers are substances made of many small molecules
joined together to make long chains. And in a NASA chemistry lab,
they have come up with a polymer that will flow at the
temperature the structure will be at as penetration occurs.
MIA: As the bullet penetrates, it pulls a little bit of the material with it.
But then, as it leaves, then the material will snap back.
And when it snaps back, it actually seals.
DAISY: This is pretty amazing stuff...
it stands up to punctures... and a whole lot more.
This is the result...
You can see where the saw cut through, but the structural integrity remains intact.
MIA: We have looked at this material for like a fuel tank application, for example,
where you shoot at it, and there’s liquid in a container,
and it actually works.
So it was gratifying to see that when we actually test this material in the field,
you can see the bullet penetrating, here, and the
material pops out and then goes back in.
We’ve done this from the side and also from the front.
The camera’s fast enough to pick up the bullet going through
and there’s a shock wave that accompanies the healing of the material.
DAISY: Similar material was already available...
Used in golf balls and targets at shooting ranges,
it had many of the qualities scientists were looking for...
but not all of the qualities...
KEITH GODON: The material, surlyn, it’s self healing,
but one of the properties it doesn’t have is that it’s not structural load bearing.
DAISY: Keith Gordon is a research materials engineer
here at NASA Langley Research Center
KEITH: What we want to do is we want to make a material
that has self healing properties, but we want to increase it,
from the mechanical properties or the structural load bearing properties.
DAISY: So Keith and his colleagues
set forth to make a material that could self heal
and have the structural integrity needed for NASA applications.
They needed to develop a material
that had more tensile strength than previous self healing materials.
Tensile strength is an important factor
in determining a material’s load bearing ability.
It is a measurement of the stress at which a material
breaks or permanently deforms.
Stress equals load divided by area.
And that was just one of the qualities they had to account for.
KEITH: That’s part of the chemistry, all of the
brainstorming in terms of the chemistry involved.
We need a material that is easily process-able.
To make a polymer you have to start with monomers,
small molecules, in hopes to making a large molecule.
And so what we have here, is we have the monomers
dissolving right now, we have another monomer
that we’re going to add that’s going to initiate the reaction.
What we hope to have after about 12 hours,
polymerization time, is a polymer.
What we’re going to do from that point is isolate the polymer,
so it’s going to go from a liquid type of appearance, now,
to a powder. We’re going to take the polymer powder,
and then we’re going to place it inside of a mold,
press it, and we’ll have our 3 x 3 panel.
DAISY: The work in the lab has produced a product
that will be beneficial for future space exploration.
MIA: For NASA applications, what we’re looking at
is space structures for example, that self heal.
Habitats for example and so what we’re interested in
is that if there’s an event where it gets hit by a micrometeoroid,
we can retain the pressure in the habitat.
And we’ve actually tested this material at close to micrometeoroid velocities.
Up to 5 kilometers per second and it does close back up.
DAISY: So work in the lab will continue, with the goal
to make NASA’s future space exploration as safe as it can be.
Keep track of this and all of NASA’s exploration missions at www.NASA.gov.
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