New Lava-Like Coating Can Stop Fires In Their Tracks (science.org) 34
sciencehabit shares a report from Science.org: It takes a lot of science to stop a fire. To prevent homes and workplaces from going up in smoke, manufacturers have added flame retardants to plastic, wood, and steel building materials for decades. But such additives can be toxic, expensive, and sometimes ineffective. Now, researchers in Australia and China have come up with a new flame retardant that, when exposed to extreme heat, forms a ceramic layer akin to hardened lava, squelching the flames before they spread. "This is very good work," says David Schiraldi, a chemist at Case Western Reserve University, who has developed other flame retardants. He notes that the ceramic's starting materials aren't particularly expensive or toxic, making it more likely to see widespread use. "[This] could impact public safety in the long run."
[The researchers] used three components. First, they created a mixture of several metal oxide powders -- including oxides of aluminum, silicon, calcium, and sodium. That mix begins to melt at about 350C (below the temperature of most flames), forming a glasslike sheet. Next, the researchers added tiny flakes of boron nitride, which flow easily and help fill any spaces between the metal oxides as the glass forms. Finally, they added a fire-retardant polymer, which they described in ACS Nano in 2021. The polymer acts as a binder to glue the rest of the mixture to whatever it's coating. That mix dissolved in water into a milky-white solution, which they then sprayed on a variety of surfaces, including rigid foam insulation, wood, and steel. After it dried, they blasted each coated material for 30 seconds with an 1100C butane torch. In each case, the coating melted into a viscous liquid, covering the material in a continuous glassy sheet.
When heated by the torch, coating spewed out nonflammable gases, such as carbon dioxide. As it did, it became more dense and formed a uniform, noncombustible char layer, which blocked flames from spreading to the materials underneath. The novel flame retardant protected rigid polymer foam -- the kind used to insulate homes -- better than more than a dozen commonly used retardants, the researchers report today in Matter. The new coating also excelled at protecting wood and steel. If sprayed on building materials during construction, the new coating could prevent disasters like the 2017 Grenfell Tower fire in London, where 72 people died, the researchers say.
[The researchers] used three components. First, they created a mixture of several metal oxide powders -- including oxides of aluminum, silicon, calcium, and sodium. That mix begins to melt at about 350C (below the temperature of most flames), forming a glasslike sheet. Next, the researchers added tiny flakes of boron nitride, which flow easily and help fill any spaces between the metal oxides as the glass forms. Finally, they added a fire-retardant polymer, which they described in ACS Nano in 2021. The polymer acts as a binder to glue the rest of the mixture to whatever it's coating. That mix dissolved in water into a milky-white solution, which they then sprayed on a variety of surfaces, including rigid foam insulation, wood, and steel. After it dried, they blasted each coated material for 30 seconds with an 1100C butane torch. In each case, the coating melted into a viscous liquid, covering the material in a continuous glassy sheet.
When heated by the torch, coating spewed out nonflammable gases, such as carbon dioxide. As it did, it became more dense and formed a uniform, noncombustible char layer, which blocked flames from spreading to the materials underneath. The novel flame retardant protected rigid polymer foam -- the kind used to insulate homes -- better than more than a dozen commonly used retardants, the researchers report today in Matter. The new coating also excelled at protecting wood and steel. If sprayed on building materials during construction, the new coating could prevent disasters like the 2017 Grenfell Tower fire in London, where 72 people died, the researchers say.
Re: (Score:1, Interesting)
Re: (Score:2)
Re: Fires (Score:1)
Re: (Score:2)
Can it protect spacecraft during reentry? (Score:2)
Heat tiles are high maintenance.
Seems like not (Score:2)
It seems like this material expands to create the coating, so then you are relying on the strength of the polymer to hold it onto whatever substrate it is attached to, seems like a tall order given vibrations/wind the coating has to deal with as it flows before it hardens. Not to mention re-entry temperatures are much higher than home fire temps (as high as 3000F or so) so not sure it would hold up.
I guess the thing going for it is that vibrations during launch wouldn't affect the coating as much before it
Re: (Score:1)
Cost and Testing (Score:5, Interesting)
If sprayed on building materials during construction, the new coating could prevent disasters like the 2017 Grenfell Tower fire in London
There already are far more fire-resistant claddings than what they used at Grenfell but they were not used due to cost. It does not matter how good a technology is at suppressing fires if your landlord is too cheap to buy it.
The fire also reached about 2000C and burnt for hours so you are going to have to do far more substantial tests than 30 seconds with a 1100C butane torch if you want to make claims like this.
Re: (Score:1)
9/11 could have been very different.
Re:Cost and Testing (Score:5, Insightful)
Probably not.
1) The impact from the aircraft broke/shattered/stripped away a lot of the flame retardant materials from the steel structure. That is, from the structure that was left after impact. Maybe this new stuff could have remained better attached, but given the violence of the impact, I'll assume "no" until testing proves otherwise.
2) The fires were intensely hot and burned for a long time. There was a whole lot of flammable material available, and tens of thousands of liters of jet fuel. Structural steel weakens at something like 400 C, and by 650 C has lost half of its strength. In the intensity and duration of the fires, it is questionable whether any reasonable amount of material could have insulated the steel well enough to prevent those softening temperatures. Combined with the significantly weakened structure (due to the initial impact), it did not take the loss of much additional structure to cause the collapse.
One might well ask: how did the towers manage to stay up for as long as they did?
The twin towers were actually intended to survive an aircraft impact. But the scenario they considered was a relatively small aircraft getting lost in the clouds, and maybe a glancing blow as the pilot make evasive maneuvers at the last second. The notion of a kamikaze-style attack using wide-body, mostly-fueled aircraft was not considered. Hell, the 767 aircraft that ultimately brought down the towers didn't even exist until about a decade after the towers' design was finished.
Further reading in this Scientific American article [scientificamerican.com].
Re:Cost and Testing (Score:5, Informative)
The fire also reached about 2000C and burnt for hours so you are going to have to do far more substantial tests than 30 seconds with a 1100C butane torch if you want to make claims like this.
The point about using fire-resistant construction materials is to prevent fire spreading, assuming there is some small source of fire, such as a faulty electrical appliance. In the case of Grenfell Tower, the cladding provided both fuel and a conduit for fire, bypassing the fire prevention barriers. At least, that is what the enquiry seems to have found so far. The blowlamp test sounds quite reasonable, if what you are testing is whether a material will support combustion in the presence of fire, i.e. will it spread the fire. By the sound of it, this coating will do a very good job in that respect, a bit like an automatic fire blanket.
Re: Cost and Testing (Score:2)
Of course, if the tower had been prepped with this stuff, it is unlikely that such a huge hot fire would have developed in the first place. Or at the very least, one hopes that it would have given people more time to get out.
But the problem with that tower was of course that safety was not the first concern of the landlord. Probably not the third, fourth or fifth concern either.
Re: (Score:1)
Cool. I mean hot. Hopefully cool on the inside.
Does it cost less than fire insurance? (Score:2)
Re: (Score:3)
If not, it economically makes sense to just pack up your sentimental stuff and have the insurance company pay for a new house.
If that were the answer, we would end up paying all our money out in insurance premiums, instead of buying stuff that is well made. I don't work in insurance, but it is pretty obvious that if the risks of fire are greater, then the premiums have to go up, otherwise the insurance company can't cover the increased claims.
On top of that, you have to be some kind of heartless bastard to think insurance can compensate for the needless loss of life due to using cheapskate construction materials.
Re: (Score:2)
But good news , the govt does. When insurance gets too expensive the govt will start underwriting it like they do flood insurance
Re: (Score:1)
Username checks out.
Re: (Score:3)
Well I have little sympathy for those who choose to live inside tinderbox forests so as to afford bigger houses.
I agree, but the people living in Grenfell Tower were not wealthy people wanting a big house in the country.
We now have thousands of people in the UK, living in places that are unsafe, and the tenants/homeowners are the ones expected to pay for the remedial work, not the landlords, or the property developers, or others who profited out of cheapskate and possibly negligent construction practices. When I go to the shops and buy some food, I don't need to take out insurance in case the shop sells me stuff that
Re: (Score:2)
It's even worse than that. Pretty much all apartments are very difficult to sell at the moment as lenders won't give mortgages for them without reassurance that they don't need remedial work doing for fire safety. The available certificates are not enough to convince them in many cases.
Anyone who does have an apartment with fire safety issues has a huge problem. Most of the companies that built them are no longer around. Often the builder sets up a company just for that project, and shuts it down afterwards
Starlite (Score:2)
So... Is this Starlite?
Re: (Score:2)
Gentlemen, behold! (Score:1)
We've found a way to fire-proof the building, by having it preemptively incinerate itself in the wake of the fire!
What's new? (Score:2)
Iceland (Score:2)
And then what? (Score:2)
You coat/spray this stuff onto a building. The building catches fire. This stuff then turns into this glassy substance which prevents the fire from spreading. Now you have this layer of glassy stuff everywhere. Do you peel it off and reapply? Chisel it off? Is what it's sprayed on now ruined and has to be replaced?
Stopping the spread of a fire is good, but if in so doing you destroy what you're trying to protect, it doesn't seem that good a process.
Re: (Score:2)
Re: (Score:2)
I'd look at it from two angles. 1) replacing the exterior of a building (or whatever portion was involved) is almost always less expensive compared to the cost of replacing the whole damn thing. This material is intended to prevent the spread - keep a fire contained to a relatively small area (volume), rather than engulfing the whole structure. 2) Survivability: if yo
Re: (Score:1)
From what I've seen, something like this would probably encourage more bozos to not get out of a fire zone when a wildfire is approaching putting themselves and rescue crews at more risk. Better to go in ahead of time, periodically, and burn down any homes where the owner hasn't taken measures to protect the homes. Like metal roofs, cutting down trees growing close to the homes, cleaning up scrub, deadfall, leaf/needle litter, and other detritus from the forest floor within a few hundred metres of the place
Re: (Score:2)
The stuff this gets fused to during a fire would have been destroyed regardless. This slows the spread of fire so less of your stuff is destroyed overall.
In the average apartment fire, you have about two minutes to get out. At this scale, any extra time will be huge for saving lives if the stuff is economical. If you're really lucky, it'll give firefighters enough time to save some of the building, or prevent it from hopping between densely packed buildings.
Looks like they read my patent! (Score:1)
No compelling requirement ... (Score:2)
... existing retardants work sufficiently well, their effects on the environment are well understood and can be mitigated, and they are relatively inexpensive. This sounds like it is a good fire retardant but bad for the environment in a) it's production b) it's use and c) it's aftermath. So why is this needed?