something new for Kevlar/cut protection???

[bill van steenwyk]

I happened to be watching the Discovery Science Channel the other evening and saw a piece about Kevlar vests used to protect folks from gunshot wounds. The premise of the piece was that although the Kevlar vests in use now for bullet protection do offer good protection for some attempted gunshot attacks, they are basically useless against a very sharp.pointed weapon such as an ice pick, sharp pointed knife or other object such as this, as when the vest or material is struck with something of this type, it typically pushes the fibers of the material aside and goes right on thru. I would suppose this characteristic is why the military used ceramic material inside the layers of kevlar. The downside to the ceramic material is it is stiff and unyielding and will not conform to the body when bending, kneeling, etc., making it difficult for people to wear.

The newest thing to get around this problem,(at least according to the program) is to use a mixture of polyethelene glycol and powdered silica mixed together and apply this to the kevlar vest. In the program clips, they just mixed the two together and poured in on the vest, spreading it out with a stiff brush so it would penetrate the fiber and then let it dry. They then tried again to stick a sharp knife, ice pick and several other pointed objects thru the vest and they would not penatrate it after it was treated with this mixture.

Now to the question that brought to my mind:

Do the folks that make our safety gear (cut suits) know about this development and would it make sense to treat the cut suits being sold to boat racers the same way. There are certainly a lot of sharp, pointed things on the bottom of our boats.

I am sure the impact from what we can be struck with would still break bones and do some damage, but possible less damage of a cutting/puncturing nature??? Food for thought and investigation if it hasn't been investigated already.

Another thought: If something like this would be beneficial for boat racing, how would the fact these suits normally get wet affect the treatment of the material.

[Ken Fleming]

I'm not sure how much it would help. Aramid (Kevlar) is extremely cut resistant the way it is as a dry cloth and actually becomes easier to cut when something is added to stiffen it up. The problem was/is that it is not puncture resistant at all, when i was in the military i spent a couple of years being a Navy cop and they showed us just how easy it was to punture a vest.

[bill van steenwyk]

puncture resistance of kevlar

That is the exact reason for this treatment. To make the kevlar puncture resistant. I thought that was made clear in the post. The TV clip said nothing about ANY harmful effect to the kevlar because of the treatment. Visually the kevlar seemed to be just as pliable, in other words this treatment did not make it hard or stiff, but by the addition of this treatment it became more puncture resistant while retaining the flexability of the material. After the treatment, attempts were made again to penetrate it with an ice pick and the attempts failed, while the material still seemingly/visually retained its flexability.

As mentioned in the orginal post, this would seem worthy of further investigation based on the video I saw. Since I am "out of the game" now so to speak, I will leave it to others if they want to take it further.

[Dave M]

I think so

I saw the same show, very cheap and easy to make this liquid I think. It appeared to not change the characteristics of the Kevlar, if anything, it made it easier to wear.

This is all new technology, and not yet developed completely. But I think it is worth looking into.

Pat Gleason, you hear anything on this from Security ?

[Ken Fleming]

I understand that it's talking about making it puncture resistant. There are very few parts on a boat that are small enough to puncture like an icepick of even a small blade. My point is that if you've ever tried to cut a piece of dry Aramid cloth it is a pain in the a@#, now take that same piece of cloth and soak in resin between 2 sheet of pastic so it like prepreg and while it's still wet and very pliable it cuts with no problems. Another problem it would cause is that as soon as liquid body armor is hit with any speed and force it becomes extremely stiff meaning if you get thrown out doing 70 mph your body will not be able to roll with the punches so to say so if your limbs can't flop around freely they will want to break or try to remove themselves whet they hit the water. then when you stop moving it will become liquid again instantaniously.

[bill van steenwyk]

??????????

Mr. Fleming:

I for one have no idea what you are talking about. Dave Mason and I both have just posted that the treatment according to the video we both saw DOES NOT CHANGE THE FLEXIBILITY of the fiber whatsoever. I am neither a chemist or engineer, just someone who reported something I saw as a treatment to make kevlar more puncture resistant while outwardly appearing NOT TO CHANGE the other characteristics of it in any way. This was both demonstrated on the video and explained verbally while the video was running. Your comments make no sense unless you are misunderstanding in some way both my descriptions of the treatment and also Dave Masons. READ IT AGAIN. If you don't think this is worthwhile in investigating further, that is certainly your perogative, but to belittle something new, with evidently no understanding of it based on your comments to this point, is pointless, especially a safety related item, unless other motives are at work here.

[Ken Fleming]

Here's a little tidbit from a company developing this new product and notice also where they say that when force applied in turns rigid. I am in no way saying that there is no way that it will or won't work. And maybe just find a few more facts about it other than what you saw on a TV do***entary. If it works as good as they say it will be great for it's intended purpose i'm just not sure that is in boat racing. The secong half of this article came from the proving grounds in Aberdeen MD. And i never said it became a solid just that it becomes more rigid.





Liquid armor protection
The uniform might be made out of fabric treated with another technology featured in the conference’s exhibit hall, shear thickening fluid. Unofficially
referred to by some as liquid body armor, STF is made of equal parts polyethylene glycol – an inert, non-toxic thickening agent used in a variety of
common products, like some ice creams – and miniscule glass particles, said Eric Wetzel, who heads the STF project team in the Weapons and Materials
Research Directorate of the U.S. Army Research Laboratory.

In a small glass vial, the light blue liquid is easily stirred with a small plastic stick – as long as the stick is moving in slow, easy motion. When sudden,
rapid or forceful motion is applied, the liquid instantly hardens, preventing any movement.

“When the movement is slow, the glass particles can flow around each other,” Wetzel explained. “But when the movement is fast, the particles bump into each other, preventing any flow of movement.”

STF has been applied to regular Kevlar material, Wetzel said. The fabric’s texture doesn’t change; it looks and feels the same as if it hadn’t been treated.
Using a test swatch of four layers of untreated Kevlar – the normal thickness of body armor – Wetzel is able to stab an ice pick through the fabric.
But when stabbing a treated section of fabric with all the force he can muster, the ice pick dents the fabric but can’t penetrate through.

Research is being done into whether STF can be of use to the Army, Wetzel said. If it is, Soldiers may start getting gear treated with it in about two
years, he added.


Liquid Body Armor



ABERDEEN PROVING GROUND, MD -- Liquid armor for Kevlar vests is one of the newest technologies being developed at the U.S. Army Research
Laboratory to save Soldiers' lives.

This type of body armor is light and flexible, which allows soldiers to be more mobile and won’t hinder an individual from running or aiming his or her
weapon. The key component of liquid armor is a shear thickening fluid. STF is composed of hard particles suspended in a liquid. The liquid, polyethylene
glycol, is non-toxic, and can withstand a wide range of temperatures. Hard, nano-particles of silica are the other components of STF. This combination
of flowable and hard components results in a material with unusual properties.

“During normal handling, the STF is very deformable and flows like a liquid. However, once a bullet or frag hits the vest, it transitions to a rigid material,
which prevents the projectile from penetrating the Soldier’s body,” said Dr. Eric Wetzel, a mechanical engineer from the Weapons and Materials
Research Directorate who heads the project team.

To make liquid armor, STF is soaked into all layers of the Kevlar vest. The Kevlar fabric holds the STF in place, and also helps to stop the bullet.
The saturated fabric can be soaked, draped, and sewn just like any other fabric.

Wetzel and his team have been working on this technology with Dr. Norman J. Wagner and his students from the University of Delaware for three years.

“The goal of the technology is to create a new material that is low cost and lightweight which offers equivalent or superior ballistic properties as
compared to current Kevlar fabric, but has more flexibility and less thickness,” said Wetzel. “This technology has a lot of potential.”

Liquid armor is still undergoing laboratory tests, but Wetzel is enthusiastic about other applications that the technology might be applied to.

“The sky’s the limit,” said Wetzel. “We would first like to put this material in a soldier’s sleeves and pants, areas that aren’t protected by ballistic vests
but need to remain flexible. We could also use this material for bomb blankets, to cover suspicious packages or unexploded ordnance. Liquid armor could
even be applied to jump boots, so that they would stiffen during impact to support Soldiers' ankles.”

[Kev43V]

it would be interesting to see at what velocity the stuff becomes "hard".
it would also spread the force out more in an impact with blunt objects not just sharp pointy ones
I am not real convinced of your breaking extremity's or trying to tear them off. if it made the arm or the leg rigid sure. But if it makes the fabric around the leg or arm rigid that is not the exactly the same physics. it would be interesting to see tests on it

[bill van steenwyk]

thanks for further information

After reading the further information about the product, my idea would be to
MORE enthused rather than less about this development, unless the material after stiffening up would then not go back to its orginal condition. Another train of thought might not see that as a bad thing, especially if the driver was thrown clear of his boat and then struck by another. I see nothing in the further information about the process to indicate that one way or another.

Like Kevin, I do not automatically think this is a bad thing. (stiffening of the material permanently if that is the case.) After all, how do the capsules mandated in many categories work?? Exactly the same way, by preventing the sharp object from reaching the body. Further investigation as Kevin mentions, would certainly seem to be warranted. Perhaps the APBA safety committee would be interested in this development, or as previously mentioned the suit manufacturers themselves if they are not already aware of this research.

The obvious problem would seem to be if the material did not return to the flexible state after impact, causing a problem mobility wise for the driver and/or EMT'S assisting them. I don't see anything in the description of the process that indicates whether the transformation is permanent. Is that available? It does say that it does not hinder the soldier from running or aiming his weapon. If it were permanent after being struck, I would think that would be a definate issue with the military, as soldiers run into things all the time. If an accidental blow would harden the material permanently, I wouldn't think they would be at all enthused as the article indicates they are.

Too bad the additional information was not included with the first post. Would have made the additional posts moot.

[Ken Fleming]

The armor will instantly return to a liquid state as soon as there is no more force being applied.

[Dave M]

Perhaps

We should look into it as an additive into the Kevlar that is being mandated into the cockpit sides ?

On the show, which is basically all th eknowledge I have at this point other than the article Ken submitted on this thread, the liquid is only rigid a spilt second, just long enough to withstand the puncture.

Let me point something out. Kevlar sucks. It tears easy, cuts very easy as it is. Just any EMT at the race how long it will take them to cut you out of it if the need arises. It currently cuts like butter with the proper scissors. I purchased so called Kevlar shears to use when building boats with kevlar. All they are is serated scissors they charge extra for because they deem them Kevlar shears. Back to my point, just this spring I got the chance to test my fairly new Kevlar. The cut went into my leg. No big deal, not a bad cut. Reason was not a flip. I had just finished rebuilding my DMR (750CCMR) and when I re-installed the rear combing wall pullies I put new bolts in (old Keller style). Needless to say, the bolt was to long, so I whacked it off with a cutoff wheel, and forgot to come back with a file to smooth out the cut. Soon as I climbed in the boat at Jessup my pretty Kevlar was instantly useless on my right hip. The bolt actually tore the stuff and allowed my skin to be scratched. Tell me again why I am sweating to death wearing the stuff while racing ? Splinters from a wrecked boat as it peels you from the cockpit could very well act as a jagged cut off bolt...... even bolts once crashed through the wood could be potential weapons.

I think the new stuff warrants some research for our applications at any rate. With the big push for saftey at each annual meeting, and with the current changes being implemented, we might as well.

[Ken Fleming]

I to was thinking that it would be a great addition to the cockpit reinforcments.

[Jeff Akers]

Stf

Great find ! ...This could be huge ( if it indeed does what it says ) Here is the link to the "Official site". http://www.ccm.udel.edu/STF/index.html

I sure hope security and life-line are aware of this !