Flamethrower vs Aerogel

[Music] This is the ultimate test of aerogel. I put myself on the line to see who wins in the Battle of flamethrower versus aerogel. [Music] So if you really want to see the insulating properties of aerogel, you got to put it to the test. This material here is like the most insulating, right? What is this?

Yeah, so this is Pyrogel XTE. It's made by Aspen Aerogel. So it's one centimeter thick. It doesn't look like the blue stuff because it's actually a fiberglass blanket that's infused with aerogel. By the blue stuff, he means this silica aerogel. It's made of the same material as sand or glass, but if you zoom into the nanoscale, you'd see it has a sponge-like structure with tiny pores just tens of nanometers across. Now, aerogel can be up to 99.8% air, but it's a better thermal insulator than air because those pores are so tiny that hot air struggles to diffuse through them. Plus, the nanoscale structure itself is a poor conductor of heat.

But aerogel is pretty fragile in this form, and so it's not really practical for most uses. Instead, what you can do is actually take tiny particles of aerogel and embed them in a composite material like blankets, but it has the additional component iron oxide, just basically rust, that makes it opaque to infrared radiation. So, it's good at stifling conduction, convection, and radiation.

On the other side of this insulating aerogel blanket, we have Ben, who he's from Cape Cod and responded to a tweet of mine when I asked if anyone in this area has a flamethrower, or, not a flamethrower in this case, from The Boring Company. Have you ever fired this before?

I have not, so this will be a first.

Okay, so what we're gonna do is try to test what the temperature is on the far side of that blanket when we put the flamethrower at full bore on to this side. All right, are you ready?

I'm ready.

All right, let's give this a try. Right here, I have the FLIR thermal camera. This is the T1020, which can record up to 2,000 degrees Celsius. First, for comparison, let's see what this flamethrower can do to something that's not aerogel. Let's put it to the test on this super-sized cheesecake. There you go.

All right, Ben. Within seconds, the temperature of the chocolate is up to hundreds of degrees Celsius. Around 30 seconds, the whole thing starts to collapse. Even after the flamethrower is removed, parts of the chocolate are still well over 600 degrees Celsius. I think this is what the internet likes. They like really hot things applied to, you know, novelty objects.

Okay, now is the time to really put aerogel to the test. He's about to put the flamethrower full bore on this side of the blanket. Just one centimeter away will be my hand on the backside of the blanket. One heart, come in.

No, I don't feel any heat. That is crazy. Propane burns at about 2,000 Celsius, so at this point, I barely feel anything. That is incredible. [Music]

They look like from the back. Feels like...

Feels warm. What about the other side? How hot's the other side?

So, this flamethrower was producing over 660 degrees Celsius on this side. Meanwhile, on the other side, we were just measuring about 50 degrees Celsius. We're going up to the highest range that this camera can do, up to 2,000 degrees Celsius. Okay, I know we're not gonna be able to see much except for the really hot stuff. Let's go for it.

That is just insane, but this blanket is still not hot. You see that with the thermal? How hot is it?

50 degrees.

See, on the thermal, I got 900 at one point. Yeah, and it's actually still... It's over 200 degrees Celsius right now.

Whoa, yeah, right there, and I can still touch it.

Yeah? Can you see my handprints after I touched it?

Wow.

Now you might be wondering how it's possible to touch something hotter than 100 degrees Celsius without getting burned. Well, for that, we need to go to another demonstration. This is a hot plate set to around 150 degrees Celsius, and on top of it is a metal plate that is mostly covered in about a millimeter of an aerogel coating called Aerolon. But a small square in the corner is left uncovered. This says about 120-627 degrees Celsius, so clearly hotter than boiling water.

So would you put your hand in boiling water?

I don't think so. That would hurt. But what about putting it on this coating? So let me try.

How's it feel?

Not like 130 degrees. It feels hot, but yeah, but it doesn’t feel like 130 degrees.

I wonder, to prove the point, there's some water in a little beaker.

When I move that...

Oh yeah, your figure!

Yeah, totally. Your handprints, thermal handprints left behind.

So I was cooling down the surface, cooling it down over here. This is not coated, and this is, I think, slightly hotter. It's about, it's...

Wow, 180 degrees Celsius.

So that is the part I don't want to touch.

Yeah, I definitely don't want to touch it because it doesn't have Aerolon on it. This is such a thin coating, it's about a millimeter, but even that millimeter of aerogel means that you can touch something that otherwise you would be totally unable to touch. This would definitely burn you, and that's why there's a little beaker of water with a dropper.

Is there you go, I moved it.

Okay, so take some of that and just to prove the point, put it on the metal square.

Let me put some of this on that piece of metal here. I'm gonna drop a little bit of water on it so we can see this really cool. The drops that splattered off onto the Aerolon coating are not boiling.

Let's have a look here.

And this water doesn't boil right there.

I don't know if this is gonna be like...

He transferred through the water.

It gets hot. Put your finger on the Aerolon itself without the water.

Right, like there?

Yeah, no big deal, right?

Yeah, I mean that's not... It's not uncomfortable. It's clearly hot, but it's not like, you know, putting your hand in boiling water, which is kind of crazy because it is hotter than boiling water, but it just doesn't conduct the energy to your hand that fast.

That's really weird. They use this for applications which they call safe touch. So that's something that would normally instantly burn you, something hot enough to boil water, you could hold your hand on for minutes and it wouldn't at all.

Okay, so far in this video, I focused on using aerogel in hot applications, but it works equally well at the other end of the temperature spectrum, at cryogenic temperatures. And this comes in handy for things like liquefied natural gas plants or by NASA when they're using liquid helium.

You need really good insulation to keep the heat out. I mean those cold pipes, if they're not insulated properly, can end up with huge ice falls on them, which not only is inefficient, it's also incredibly dangerous. So this is one of the major applications for aerogel these days. If you take a piece of cryogel and dip it in liquid nitrogen for a good while, it is still flexible when you bring it out, and that's kind of essential when you're working with material that needs to function at ultra-cold temperatures.

Here is a carbon aerogel that has been submerged in liquid nitrogen, and as that liquid nitrogen turns back into the gas state, it functions like its own air hockey puck! Except instead of the air coming from the table, it comes from the puck itself. You can even buy ski jackets these days that have special aerogel lined pockets that stay significantly warmer than standard jacket pockets, and they're specially made for your cell phone so that it doesn't freeze up in the cold weather.

You know, I feel like this is a story of something that started as an oddity, as something that didn't really have applications, but clearly is an amazing insulation and can be made into a really strong fire retardant material.

Why would they insulate subsea oil pipelines with this material? That's a really interesting question. So this was what we would call the killer app for aerogel. The oil that comes out of wells in the deep ocean is very viscous and saggy.

And so, if you just had a pipe with that oil, it would basically gum up. And so what you have to do is put another pipe around it and fill that gap with insulation. It's called a pipe-in-pipe configuration, and so they heat the oil—they have to keep it flowing—but you need to insulate that so that it doesn't lose all of its heat to the cold temperatures of the surrounding ocean.

So if you think about laying pipes like that from a ship, you have these long segments of pipe that the ship has to basically pick up, put over the side of the boat, and drop down to the ocean. So, you know, at some point, the pipe becomes so big and so heavy it capsizes the boat. So, there are really only three vessels on the planet that are big enough to lay that really large diameter pipe for subsoil pipelines.

Aspen Aerogels came along and said, "Hey guys, we've got this really great new insulation. It's three times better than polyurethane." So, I can take this much polyurethane foam and shrink it into an insulation that's that much aerogel.

Now what it did was allowed you to shrink the outer diameter of the pipe in this pipe-and-pipe configuration substantially, and because of that mass reduction from the smaller diameter pipe, all of a sudden, 250 ships around the world can lay that smaller diameter pipe without any loss of performance in the oil pipeline.

And so that resulted in alleviating years of backlogs of these pipelines that need to get laid and saved billions of dollars. Now when we filmed this video, I knew the title would probably be something like "Flamethrower versus Aerogel," but I didn't think of it like a real battle.

Like, what would it mean for the aerogel to win? That it just, you know, didn't get hot or something? But as it turns out, in the flamethrower user manual, it instructs you only to ever pull the trigger for seven seconds at a time maximum. But to get the shot and to get the blanket hot enough, I frequently told Ben to pull the trigger for 5 or 10 times that long.

That's like... that was like triple. Okay, and what we noticed over the course of the shoot was that the flamethrower was working less and less well. We thought it was out of fuel, but it just turned out something inside it was breaking. By the end, we couldn't even pull the trigger.

So, I'm sorry, Ben. And in the battle of flamethrower versus aerogel, I think aerogel definitely won.