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I feel confident
You're confident that I am NOT gonna be damaged?
not permanently
okay
let me back up for a moment. I want to talk about the properties of aerogel
the world's lightest solid.
What I'm gonna do is I'm gonna lean in so it's
coming in through this mic and then can you do that again yeah
this is what it sounds like
that is weird
it has a metallic ring first recognized
by aerogel's inventor Samuel Kistler all the way back in 1931.
now aerogel is an
excellent thermal insulator but it's not the easiest material to work with can I
try it sure oh I didn't I don't quite have the touch oh I can't I make it ring
oh no look it didn't take a whole lot to break it right it breaks pretty easily
so is there a way to take the extraordinary thermal insulation of
aerogel but make it more usable what I put together here is just a combination
of aerogel particles silica aerogel particles and a non-flammable binder and
you should be able to put it on your your skin and hit yourself with the
torch should right I'll give it a shot okay so you just take a little bit and
squeeze it around your finger just around yeah just squeeze it around here
one finger a two fingers you want matter how's that am I am i doing it oh yeah
that's that's yeah I'll be good just wanna make sure the fire when it goes
around your finger doesn't hit the Bearskin seems like it's pretty thin
around this finger tip here like how thick should it be you're making me
nervous holding a blowtorch can I do the
blowtorching or you can do the blowtorching absolutely because I mean
if this is if this goes wrong so how hot is a blowtorch flame well it's really
hard to tell but from our experience it's usually you know at least 1500
degrees C and can get as hot as 2000 so yeah this is very hot all right let's
try it this is so wrong that little jittery pot there I you know it looks
like I'm toasting a marshmallow whoa why is it flaming like that and
what is burning binder right now correct should people just hold the rate on
there it doesn't feel hot at all my finger does not feel hot at all
that is insane right there propriety I cannot believe how a little
warmth I feel passing through that the FLIR 10 2013 10 per ature ranges and
here the aerogel is clearly hotter than the 160 degrees Celsius upper limit I
mean it's glowing orange hot so it's clearly incredibly hot I mean if you can
see the blackbody radiation you know that it's very hot so we went
to the highest temperature range so this goes up to 2,000 Celsius 881 907 907 907
degrees Celsius that is absurd pretty good right in front of my finger
what so this was was about almost a thousand Celsius but behind this thin
layer of aerogel my fingers are just just warm Wow I mean it is clear this
stuff insulates this video is about taking air gels extraordinary properties
and improving on them for example I'm about to step into this pool without
getting wet there's a layer of air there right next to my skin that thin layer of
air is what makes my skin looks silvery light from certain angles reflects off
the water air interface in what's called total internal reflection that is very
strange this is a really cool effect I mean just besides the fact that I'm
basically waterproof I feel like this extra air on me is making me more
buoyant than usual let me try coming out by the water and
see if I'm still dry
that is true I don't I don't really feel wet at all
that was weird really weird so how did I make myself waterproof I did it with
aerogel particles by taking a bucket of them and coating myself with the tiny
best but this is a kind of strange way to become waterproof because normal
silica aerogel is hydrophilic there we go now this is a hydrophilic aerogel so
all those OAH groups inside the aerogel are absorbing the liquid and causing the
aerogel structure to collapse aerogel is really good at absorbing water for two
reasons first it contains a lot of surface area due to its nano scales
sponge-like structure an ice cube sized piece of aerogel contains half a
football field of surface area that makes it good at absorbing lots of
molecules something scientists have sought to exploit my favorite
application which I still think today is a good idea is what's the idea is a a
physical insecticide so most insecticides work by being neurotoxins
they're called cholinesterase inhibitors it's the same mechanism as nerve gas and
we spray this on crops and things but a physical insecticide works by basically
getting stuck to the outer skin of the insect and and basically sucking all the
moisture the or the oils out of them to the point where they just sort of dry
out to death it's kind of like putting salt on a Sluggers yeah that's a very
good analogy exactly the other reason it's good at absorbing water
specifically is because it's structure is covered with OAH groups which attract
water molecules and that makes it ideal for use in museums in the past I've been
working with a company in Italy called opium which makes Museum cases I mean
they made the case for Mona Lisa they are interested in putting aerogels in
the cases because it's a passive moisture a regulator essentially once
you have it inside if the moisture increases the original
a lot of it if it decreases it releases some of it air gels ability to absorb is
even being used right now to help detect Mars quakes these were the ones that
were made for the NASA insight mission this aerogel looks like chalk because
so-called zeolite particles are dispersed throughout it they can absorb
moisture even at very low pressures there's a seismometer that contains
three small seismometers and requires since they're so small they require
exceptional vacuum inside otherwise the motion get stamped so that's what we
developed this for the zoo lights were helping absorb the moisture
predominantly that was coming off of the hypotheses and gave me some gassing
different things so that is it's sort of maintaining the vacuum by keeping -
pulling things it's actually a vacuum ball if you think of it that way and
what's interesting about it is it does not require any power any consumptions
very light so essentially this is what enabled the inside mission to work
aerogel can absorb up to 25 times its weight in water but for some
applications this is less than ideal so once we've done this is that piece of
aerogel ruined now pretty much yeah that's that's entropy irreversible
damage there to counteract this issue we take a hydrophobe it's a reactive
chemical that when it touches a no H group spontaneously rearranges with that
o age group and creates this big non-polar group and that repels water so
by replacing just 30% of the Oh H groups that line the inside of the aerogel with
these hydrophobic groups you can make an aerogel that perfectly repels water so
here water bounces off it's totally impervious it does not penetrate in and
it can sit on water for months and it will be just the same as if it was never
wetted at all you ready I guess let's go shot there it goes
it feels funny cuz it like it hardly feels like the water is touching me
because in a way the water isn't touching it's not touching you
that's what's amazing at the molecular level it is being repelled look how
crazy that it's like a weird laminar flow this is so trippy
so aerogel can be made impervious to water or more adsorbent it is naturally
brittle but it can be worked into a sticky paste and so far I've really only
focused on silica aerogel but air gels can be made out of all sorts of
different materials so all of these materials are nano structured that's
right and they have nano sized pores around 20 nanometers in size that's
right and they are over 50% err correct which is why they're also light
lightweight yeah some of them are made of polymers and there is a trade-off
between thermal and mechanical properties a traditional silica aerogel
is typically around 15 milliwatts per meter Kelvin thermal conductivity so
that means about 3 times 2 to 3 times better insulating than styrofoam these
materials would be between one and a half to two times more insulating than
styrofoam somewhere around 20 to 26 milliwatts per meter Kelvin this is a
poly a madero gel this chemistry came from NASA so it's a great insulating
material but it's not flammable knock on it it feels like wood internally we call
it Martian tape another way to make aerogel more workable is to incorporate
it into composite materials like blankets something that's in between
silicon and silica that feels nice it feels very nice doesn't this feels like
almost like a stuffed animal yeah exactly
so this is a new type of aerogel blanket that in the future we may find in
something like an astronaut suit or maybe even apparel what this material is
actually it's fiberglass it does feel like it's a fiberglass that's been
infused with aerogel and so that fiberglass aerogel composite
so because aerogels are traditionally very fragile bike um
positing it with the fiberglass allows you to make something that can be flexed
and cut and sewn and wrapped it's not the most cuddly it it sheds dust when
you tap on it but go ahead and dust is that that's silica aerogel to morphus
silica and it's it's very safe it's not for example like quartz fiber or
asbestos which are you know long aspect-ratio fibers that the body has no
chemical means or physical means of breaking down this stuff is readily
captured and and expelled by the body and it's it's not dangerous and this is
what they use to insulate subsea oil pipelines and refineries and all sorts
of applications so just that thickness will insulate a pipeline yeah so that
thickness that that one this is one centimeter thick in one centimeter you
get the same effective insulation value as three centimeters over an inch of
mineral wool or fiberglass by itself so it's a tremendously better insulator
this blanket is actually what I'm gonna put to the test in the final episode of
the aerogel trilogy so subscribe if you don't want to miss it