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Liquid Armor the New Bulletproof Vest
kjh1 writes "Armor Holdings Inc. plans to start selling their 'liquid armor' next year. The new armor, originally envisioned to be spread on like peanut butter, is instead sprayed onto Kevlar in ultrathin coats. From the article: 'it's a mix of polyethylene glycol, a polymer found in laxatives and other consumer products, and nanobits of silica, or purified sand. Together they produce a "sheer-thickening liquid" that stiffens instantly into a shield when hit hard by an object. It reverts to its liquid state just as fast when the energy from the projectile dissipates.'"
There's a video on break.com where you can see the liquid armor in action - it's pretty amazing:
clicky
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Ok, forget the bulletproof vests, because I'll never need one. But how much would it cost to coat your car in this stuff? And would it give extra protection?
Philosophy.
First the military is developing something called an "ultrasonic tourniquet", now somebody is making bulletproof peanut butter?? Fuck this shit, the universe is just too weird right now. I am going to bed.
"it's a mix of polyethylene glycol, a polymer found in laxatives..."
As if having a gun fired at you isn't enough to make you shit your pants...
Can they produce gloves able to stand up to shark bites ?
How about gloves for butchers ?
Would they be cheaper to produce than the steel-ring gloves used today ?
Are they water proof ?
How do they react to heat; could they be used in motorcycle clothing ?
Wanna fight ? Bend over, stick your head up your ass, and fight for air.
But could it stop a lightsaber? Cause you know there's scientists in North Korea working on lightsaber technology. Mr. President, we cannot allow a lightsaber gap!
No boom today. Boom tomorrow. There's always a boom tomorrow. - Cmdr. Susan Ivanova
So basicly they're making military use custard (being gentle will let you penetrate it, but use force and you bounce off). Buug how will this stand up against a knife or a bayonet? I know in the modern era this is more or less mute, but it's still something I'd personally wonder about.
I like muppets.
Product Announcement! New, glistening panty-hose. Shimmering as if they're wet. Catches eyes. Attracts only the daring. Promotes celibacy and abstinence!
... humiliation as you try again and again, unable to even stretch the panty-chasty-hose. The situation goes... limp.
In the heat of the moment, you push her against the wall and kiss. Heat. Fire. Desire. You reach down below her skirt, and trying to be spontanious, rip at her pantyhose... but wait! No satisfying tear or gasp escape from her lips...
"Liqui-hose, helping you dodge a bullet every night."
This stuff sounds like a dilatant.
Kitchen experiment: take some cornflour and some water. Mix one part of water to about two parts of cornflour until you get a thick paste. Play with it.
If you apply gentle pressure, it behaves like a fluid. If you apply strong pressure, it abruptly solidifies. Scoop up a handful and throw it at something, and it'll bounce. Drop something heavy into a bucket of it and it'll sink.
Beach sand also manifests this behaviour, under certain situations; occasionally you can find a patch of heavily waterlogged sand that's rock hard when you walk across it, but if you stand still you slowly find yourself sinking in.
Disclaimer: cornflour almost certainly does not make good body armour.
You'll still get an impact from the energy alone. You're not thrown back, but certainly hit. I imagine that hundreds of bullets would be enough to cause some quite significant effects anyway. (The total heating alone could be "interesting".)
The problem is not only the bullet's ability to pierce the armour, but the energy it transfers through the armour. This company : http://www.d3o.com/ use a similar technique but instead of leaving it as liquid, they treat it in a way which turns it into a foam structure. I beat the crap out of a friend's elbows and knees with a shovel while he was wearing d30 stuff, and he didn't feel a thing. It's quite amazing.
...but look down. We'd have joined each other in death.
--Dune
Armor-piercing bullets tend to create less damaging wounds than soft bullets that are designed to expand upon impact and dump all of their energy quickly.
Mea navis aericumbens anguillis abundat
Darn. Now I'll have to respec my Rogue to use maces instead of daggers.
A polar bear is a cartesian bear after a coordinate transform.
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I stand corrected. View the very nice clicky post at the beginning of the comments to understand how it really works.
The question is, can it be used (in sufficiently thick amount?) without hard-to-get materials like kevlar? I am really asking if you can make this at home. From the brief vid, it looked like point 5) above is very possible.
"Sintered Armorgel ; feels like gritty jello, protects like a stack of telephone books"
Maybe they should ask Neal Stephenson about using that as an ad slogan.
Except 3 rounds from a 45. planted square on his chest will either A: Knock him on his ass. B: Bruise his chest and wind him C: If your lucky pop his sternum D: All of the above Body armor just makes it so the round doesn't kill you. It still hurts like hell. Your body is still absorbing the energy of the round.
You mad
That was my objection to the movie. If you read the book, they all had mobile armour (and not soft, liquid armour either) with jetpacks and were spread about 100 yards apart when in combat. The only thing in that movie had in common with Heinlien's work was the title
Atlas stands on the earth and carries the celestial sphere on his shoulders.
Nice stereotyping.
What if the prime reason for my big SUV with the big tires, and the skookum bush bar on the front is so I can say, go offroad? I grew up in a remote town, but now due to work I have to live in the city. I drive my bush beast on the road not to intimidate as you say, but rather for my own reasons. I like to throw my boat on the roof and go where few can go. My friends and I found a sweet de-activated logging road one day with trees growing in the middle of the road that were 2 meters tall. Sorry, but your honda civic can stay in the city. There was nobody around for prolly 15km. When I got back to work the next week, I was much less stressed out and misserable. Something about tossing a new propane cylinder in a fire puts a nice close to a sweet adventure! I believe in low impact offroading, but when the trees are in the middle of the road... fair game I say.
Now, thos SUV's with the low profile tires and chrome bush bars... I agree with you on that.
Yep, and there are plenty of people that need an SUV for work or whatever. Most anti-SUV people I know don't have a problem with people that actually need something like that. The Chevy Suburban has existed since the 30s or something, LONG before the SUV moniker and hatred appeared, and they've sold models every year they made them.
Well because it's shear-thickening liquid, the more violent the impact, the more it locks up and spreads out the impact. One market that they are initially targeting is prison guards because the threat to them is from stabbing rather than gunshot or shrapnel, which the liquid armor stops yet remains flexable unlike plate armor that is rigid. The thing that will always annoy you when wearing armor is weight, heat build up and lack of flexability; this stuff should put a dent in all three.
Apocalypse Cancelled, Sorry, No Ticket Refunds
If this is really what you bought it for (and actually do), Congratulations. You are one of the 0.5 % of SUV owners who actually should own an SUV. Unfortunately, 99.5 % of them are owened by soccer moms and men who need to overcompensate for something, and are just endangering us all on the roads, and burning very excessive amounts of gasoline.
Everyone has forgotten their classic SciFi.
Nice pair of Deerskin gloves with a layer of this inside would make brass knuckles so obsolete...
I became suspicious when I read the phrase "nano bits of silica". Nano technology my big toe: that's a marketing flourish.
The article mentions that this is a sheer thickening fluid, what they probably mean is shear thickening. That would be a fluid where the coefficient of viscosity increases with increasing strain rates, instead of remaining the classically Newtonian constant. In this case it's probably because the glycol tangles around the silica particles and can't untangle quickly.
While it's quite possible the material can become a semi-solid for the brief duration of a dynamic impact there is no reason to believe, and lots of reasons to not to believe, it becomes a particularly strong solid. In a particulate reinforced composite, which this is in its pseudo-solid state, the matrix (the ethylene glycol) is important to the strength and being a simple organic molecule it's strength must be on the same order of, say, polyethylene.
TFA itself infers this, noting the original idea of using the material itself (in peanut-butter mode) didn't work out. Instead it is employed as the matix in a conventional fiber composite using Kevar or Spectra or something like that as the workhorse.
As in all conventional fiber composites, the fiber bears the load, the matrix supports the fiber. In this case the support, I conjecture, amounts to preventing the fibers from displacing away from the impact point, probably allowing fewer layers of fiber to absorb a given impact energy.
Whle this is innovative and a good idea, it's hardly liquid armour. What I would hope for and maybe expect is better performance against pointy, hard, teflon-coated projectiles of the cop-killer variety which work by nosing the fibers out of the way.
Equine Mammals Are Considerably Smaller
Larry Niven's Known Space series has armor exactly like this, that stiffens on impact. The only thing the armor has in common with Dune is that a slow impact gets through, IIRC in Dune they used some kind of force field. Larry describes what it's like to try to run in a suit like this while being peppered with automatic gunfire. Kinda funny. I don't think the Dune force fields stiffened up and made you fall over while being shot...
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
Point #1: Momentum is a vector quantity. This means that a bullet approaching a person from the left and a bullet leaving said person, heading right, have totally different momentum vectors.
Point #2: In situations where outside forces can be ignored (such as a bullet impact), momentum is said to be "conserved". This means that any momentum change the bullet experiences has to be equal and opposite to the momentum change the person experiences. A bullet of mass "m" which is travelling to the right at speed "v" has momentum "mv" (taking the direction "right" to be positive). Similarly, the same bullet travelling to the left at speed "v" has momentum "-mv". Therefore, a bullet which ricochets off at its initial speed has TWICE the momentum change compared to a bullet which simply stops. As a result, the person has to experience double the momentum change as well.
This means that a ricochet imparts MORE momentum to the target than an embedded bullet would, which is (as another poster remarked) why solar sails are reflective.