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Biotech Science Technology

Wood Pulp Extract Stronger Than Carbon Fiber Or Kevlar 208

Zothecula writes "The Forest Products Laboratory of the US Forest Service has opened a US$1.7 million pilot plant for the production of cellulose nanocrystals (CNC) from wood by-products materials such as wood chips and sawdust. Prepared properly, CNCs are stronger and stiffer than Kevlar or carbon fibers, so that putting CNC into composite materials results in high strength, low weight products. In addition, the cost of CNCs is less than ten percent of the cost of Kevlar fiber or carbon fiber. These qualities have attracted the interest of the military for use in lightweight armor and ballistic glass (CNCs are transparent), as well as companies in the automotive, aerospace, electronics, consumer products, and medical industries."
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Wood Pulp Extract Stronger Than Carbon Fiber Or Kevlar

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  • by Anonymous Coward on Tuesday September 04, 2012 @12:46PM (#41224267)

    Who needs transparent aluminum when you've got transparent, bulletproof wood?

  • by virgnarus ( 1949790 ) on Tuesday September 04, 2012 @12:53PM (#41224377)

    So I take it we'll be seeing the next president riding around in a wood-sided grocery getter?

  • by Anubis IV ( 1279820 ) on Tuesday September 04, 2012 @12:55PM (#41224407)

    It seems as if being stiffer than Kevlar may limit its usefulness in certain applications, such as body armor and the like. That said, the summary mentioned composite materials that simply use it as a component. Any material scientists around who can comment on whether its an issue or how this stuff might change things?

    • being stiffer than Kevlar may limit its usefulness in certain applications, such as body armor and the like

      Scale mail.

    • by Ogive17 ( 691899 )
      I'm sure a mold could be used to form it into a shape that would be comfortable as a body armor. Think of Batman's suit.
      • by Beardo the Bearded ( 321478 ) on Tuesday September 04, 2012 @01:49PM (#41225165)

        I'm always thinking of Batman's suit.

      • It's not the shape that he's concerned about. You want some give and flexibility, else all the kinetic energy of a projectile will be absorbed.

        Sure, it might not penetrate you, but neither does a sledgehammer. You still wouldn't want one of those to the gut, would you?

        • That depends. If the plates are contoured to fit the soft tissues underneath and spread the impact it would help a lot. Absorbing the kinetic energy of a bullet or bit of shrapnel and spreading it out over your entire torso would be much prefered to the alternatives. Flexibility doesn't magically stop all that energy from being absorbed, it does however slow down the punch so that it might not be as catastrophic.

    • by Scarred Intellect ( 1648867 ) on Tuesday September 04, 2012 @01:47PM (#41225137) Homepage Journal

      Current body armor (and I'm talking about the Interceptor vest, MTV (Modular Tactical Vest) and the Plate Carrier) don't have anything to do with the word "flexibility". The armor plates (Small Arms Protective Inserts, or SAPI) are stiff; they're slightly contoured, the front being the same contour as the back, which makes sense if you're disfigured I suppose...I digress...

      Since current vests don't provide flexibility at all, then the CNC being stiffer won't have much of an effect. It will, however, be wonderful to save on weight, those vests get cumbersome fast. But those are ceramic. Replacing those would be much more effective than replacing the Kevlar, I would think, in terms of weight-saving.

      The Kevlar itself is light enough (disclaimer: I was an infantry machine gunner), it's the SAPI plates that were/are horrible to deal with.

    • "Stiff" in this case doesn't have to mean that the final textile product and garment is actually inflexible. There is a lot more to the design of the textile that determines that. A lot of factors come into play in the design of the textile and then the final garment. Stiffness is one, but so is ultimate strength, elongation or stretch ratio, density and toughness not to mention fiber size (the "nano" here is the real important part").

  • Paper armor (Score:5, Funny)

    by K. S. Kyosuke ( 729550 ) on Tuesday September 04, 2012 @12:58PM (#41224447)
    I *knew* I should have patented the paper armor I made for myself when I was a kid.
    • Re: (Score:2, Interesting)

      by sexconker ( 1179573 )

      I *knew* I should have patented the paper armor I made for myself when I was a kid.

      Mythbusters did it - they made effective (for some uses) paper armor that fit descriptions of such from ancient China.

  • The product possibilities are endless, but I think bullet proof west with integrated brew station will be the greatest hit. Survive the tough battle, add water and yeast - instant celebratory beverage.
  • by Zibodiz ( 2160038 ) on Tuesday September 04, 2012 @01:01PM (#41224503)
    One of the biggest problems with building a race car/truck is often the cost of the materials. The stiffer frames built from carbon fiber are insanely expensive. Imagine if we could build a frame out of this for around the cost of steel --the technology could then be used in ordinary cars, with a huge weight savings, and a safer, stronger frame. It could revolutionize the automotive design industry.
    • I was driving a 10 year old Geo Metro. I was having steering problems so I took it to a mechanic. After putting the car on a lift, I was informed that the car should be sold for scrap since the frame was so rusted that the passenger front wheel had broken off. So if they could make a frame that did not have any problems with rust, I would be very interested in it. Twice a year I had the oil changed and not 6 months before it broke, I had the muffler system replaced. Not one of those mechanic said anyt
      • by Zerth ( 26112 ) on Tuesday September 04, 2012 @01:45PM (#41225115)

        So instead of rust it will be "oh, looks like you've got termites in the bodywork. Might as well chop it up for firewood."

      • I mourn your loss. For never a greater car was ever built than the Metro. However, they are not strangers to rust. My second Metro died from a tire change in much the same way.

      • s/rust/rot/

        Actually, I imagine it'll just be treated with fungicide. Fungi love cellulose.
    • by drinkypoo ( 153816 ) <> on Tuesday September 04, 2012 @01:29PM (#41224867) Homepage Journal

      The vulnerability to moisture makes it unsuitable for use in street vehicles unless stringent safety regulations are backed by frequent inspection. It would be dandy for high-end race vehicles, though.

      • by gl4ss ( 559668 )

        I'll bet you can rinse it in resin to make it waterproof.

      • Cold molding (Score:4, Interesting)

        by Kupfernigk ( 1190345 ) on Tuesday September 04, 2012 @03:32PM (#41226475)
        Far from it. Many boats are made by "cold molding", in which you start with a mold and build up your own plywood layers on top using thin veneers and epoxy resin. The result is light, strong, and very water resistant indeed if done properly. Some woods such as mahogany and utile are already extremely strong and stiff (comparing equivalent mass/area) compared to e.g. aluminum and fiberglass, and this looks like it would be more of the same, only much easier to form.
        • Boats are monocoque and you can inspect them visually pretty trivially, since water damage changes the color of the wood. With that stuff tucked up under a car and covered in undercoating an inspection will not be so easy to carry out.

    • This was tried in the past but fell out of fashion:
      CNC car body []

    • Usually the frames are made of chromoly or stainless steel, body panels are made from CF - the big exception being F1 where they use a CF monocoque.

      CF body panels actually give very poor value for money...but if there's a lot of money to spend...

      On regular production cars on the other hand, CF or a substitute could be very useful because they have to meet safety standards and you don't get the benefit of 6-point harnesses or helmets with HANS devices.

      • I'm not very familiar with Nascar, etc., but in the off-road race truck world, there's nothing more popular than a carbon fibre tube frame. Since that's my area of interest, that's what I'm familiar with; but I'm surprised other racers don't use it as well. It seems like what's good for the goose would be good for the gander.
        • Huh I've never seen a CF tube frame (unless you mean a metal one with CF reinforcement). I've competed in offroad rallies and never heard of them. Got any links?

          • My cousin got one made for his sandrail, but for the life of me, I can't seem to find any reference to such an animal. This was about a decade ago, and I've since lost touch with him -- now you've gotten me seriously curious. I have a few family members that have been competing for years to have 'the best', and last I'd heard, he was winning, but since I've moved elsewhere in the country, I'm not in contact with it much. At the time, I (being poor) was more of a Jeep guy, while most of the family focused
            • All I can find is a single company that makes roll cages for Porsche 997/996s -- so it's undoubtedly available somewhere, but I got the impression it was being custom made. Roll cage [] and a picture [].
    • I don't think that there's anything inherently expensive about carbon fibre. The raw ingredients aren't really that expensive. I'm pretty sure a lot of the price has to do with patents on various polymers that are used, as well as other aspects of carbon fibre construction. I'm waiting for the day when carbon fibre actually becomes the cheapest method of creating a bike. With the rising price of metals, and the ever lowering costs of carbon fibre, it will eventually be the case that carbon fibre (or thi
    • Does this mean we'll need new car insurance for termites and weevils?
    • One of the biggest problems with building a race car/truck is often the cost of the materials. The stiffer frames built from carbon fiber are insanely expensive. Imagine if we could build a frame out of this for around the cost of steel --the technology could then be used in ordinary cars, with a huge weight savings, and a safer, stronger frame. It could revolutionize the automotive design industry.

      But how much of that insane cost is due to the materials? A large amount of it is due to the labor that is needed to coat and lay the different layers of material and vacuum bag it. There aren't a lot of automated systems for doing this. I'm sure there could be, but I would guess that larger manufacturers would not want this either. It becomes a lot harder to sell new vehicles when the structural components no longer rust or the body doesn't get dings like steel.

      Still, the manufacturing aspect becomes qui

  • by UnknowingFool ( 672806 ) on Tuesday September 04, 2012 @01:03PM (#41224521)
    So does this mean that Ikea furniture will now be bullet proof too?
  • Wood armor (Score:5, Informative)

    by kwishot ( 453761 ) on Tuesday September 04, 2012 @01:04PM (#41224541)

    Wood armor - we're back to the medieval days!

    As with most (all?) engineered wood products - what about when it gets wet?

    From TFA:

    Swelling introduces a large number of nano-defects in the cellulose structure. Although there is little swelling of a single CNC, water can penetrate into amorphous cellulose with ease, pushing apart the individual cellulose molecules in those regions. In addition, the bonds and interfaces between neighboring CNC will be disrupted, thereby significantly reducing the strength of any material reinforced with CNCs. To make matters worse, water can move easily over the surface/interfaces of the CNCs, thereby allowing water to penetrate far into a composite containing CNCs.

    They suggest painting it. To be honest, I'm a skeptic. We wore body armor during my time in Iraq, and the abuse that our gear received cannot be overstated. Rain, heat, jumping over walls, dealing with mud. No thanks, I'll stick with Kevlar.

    • It sounds like they will be using CNC to armor cars or windows rather than body armor. In such applications, you could paint it, then stick it somewhere it won't be touched on a day-to-day basis, such as between the car's body panels. If the CNC is so much cheaper, you probably could put a lot more of it if weight allows.

      I'll note that Kevlar and Spectra also have problems with high humidity/high temperature conditions. Dragon Skin was supposedly revolutionary body armor that got stopped by the military. Th

    • by jandrese ( 485 )
      I guess you could cover it in a thin layer of epoxy after painting (adding weight), but yeah moisture control is going to be a problem in that situation from the sound of it.
      • I can't see a sealant layer adding any weight of significance.

        • by jandrese ( 485 )
          You might be surprised how much paint can weigh. On a car the paint adds about 8-10lbs or so. On something like bodyarmor you could easily be looking at a pound or more of extra weight for a relatively scratchproof coat of epoxy. Body armor is already designed with a tradeoff of weight versus protection, so anything that adds weight without adding protection is going to be carefully scrutinized.
          • For a great example of paint weighing a lot, look at the space shuttle. Ever wonder why the external fuel tank was orange? well, if you look back at the footage, the first few external tanks where painted white. The orange is the sprayed on insulation on the tank. after the 3rd one, someone at Lockheed (who made the tanks) realized that they could save 600lbs of launch weight by not painting the foam after it was sprayed on.
      • Look up Wood Epoxy Saturation Technique.
    • My (non wood) vest came with a notice to avoid water/moisture.
      Don't know if it as big an issue for military grade vests because special coatings may be applied....
      Too many Google hits to bother listing.

    • by Dinghy ( 2233934 )

      As with most (all?) engineered wood products - what about when it gets wet?

      So it's not really bulletproof against a watergun?

    • by Bigby ( 659157 )

      So logically, if it weighs the same as duck...

  • Comparisons (Score:5, Informative)

    by Sez Zero ( 586611 ) on Tuesday September 04, 2012 @01:04PM (#41224545) Journal
    The chart from TFA is all you really need to know.

    Material, Elastic Modulus, Tensile Strength
    CNC, 150 GPa, 7.5 GPa
    Kevlar 49, 125 GPa, 3.5 GPa
    Carbon fiber, 150 GPa, 3.5 GPa
    Carbon nanotubes, 300 GPa, 20 GPa

    So a great compromise material when you take cost into account, if it comes to fruition.

    • Re: (Score:3, Insightful)

      by crizh ( 257304 )

      It would be nice to know how strong it is in compression as well as under tension.

      Those figures for Carbon fibre are bollocks BTW. Elastic Modulus varies from a third to five times that depending on how it's made. My gut tells me Elastic Modulus ought to be in MPa rather than GPa. Could be wrong but Wikipedia will know the truth of it....

      • Re: (Score:3, Informative)

        by crizh ( 257304 )

        I'll correct myself then.

        Tensile strength should be in MPa. Those figures are all correctly adjusted but the Carbon Fibre ones are again wrong.

        Typical figures are from as low as 0.25 GPa all the way up to 7.1 GPa.

    • Sorry, but elastic modulus usually isn't a big consideration, unless the structure has to be extremely rigid for some reason. Otherwise, you might as well let them flap in the breeze like airplane wings. []

      The best way to compare materials is a plot of density vs. tensile strength. [](Java warning!) In this plot, the materials in the upper left corner are ideal. TFA states the material's density as 1.6g/cc (or 1600kg/m^3) and the tensile strength of 7.5GPa (or 7500 MPa) which would make it the best material
    • The problem I see with that chart is it's comparing macroscopic material properties to microscopic material properties. The stats for kevlar, carbon fiber, and steel (which are in TFA but you omitted) are macroscopic measurements - sizes and lengths you'd use in real-life construction. The stats for CNC and carbon nanotubes are for microscopic samples. The sample crystalline cellulose given in TFA is only 5x300 nm in size.

      For comparison, the crystalline grains of steel are a few to a hundred micromete
  • So when can I buy a "wooden" bike frame? Extra bonus points if it can be composted (along with me) when it gets totaled by a hit-n-run driver.

  • Stronger burn rate too, I assume.
  • So when can I order my super-light, super-stiff CNC composite racing bicycle? Please? Is there a pre-order process? Can I put it on lay-away?
  • by Ukab the Great ( 87152 ) on Tuesday September 04, 2012 @01:30PM (#41224879)

    Goes to show that Pykrete [] was ahead of it's time.

  • by N0Man74 ( 1620447 ) on Tuesday September 04, 2012 @01:30PM (#41224881)

    In the future, there will be a Legend of Zelda game where the Wooden Shield will be the best shield, rather than the starting shield.

  • Yes, but how long will it be before I can run it through my reprap? You see, I need all my projects to be completly 'bullet proof concepts' before commiting them to physical models.

    Ok, a little more searious question, how well does it hold up to long term water exposure? Will it rot from sustained moisture or degrade out in the environment, and more or less than kevlar? A super fiber material is only super if it lasts a long time out in the environment.

  • by ace37 ( 2302468 ) on Tuesday September 04, 2012 @03:10PM (#41226229) Homepage

    This will require some years of development, but it certainly shows promise.

    The strength and stiffness of a fiber are not the performance we'll directly obtain from the materials. It's more like a potential number. Typical 'carbon fiber' products have on the order of 60%-75% fiber and 40%-30% plastic by volume, where epoxy is one of the most common plastics. The carbon fibers contribute strength and stiffness, but it would fracture easily with a rigid binder. The softer plastic binder acts to share and redistribute loading efficiently (after some fibers break) to keep the carbon fibers more or less all carrying load effectively.

    They'll have to go experiment until they find which plastics work well with this. That took a long time for composites since if the plastic binds too strongly to the fibers, the resulting composite is very brittle and loses a lot of potential strength. Also, to optimize the bond strength, carbon/kevlar/glass/etc fibers are typically treated with a 'sizing' that help the fibers bind optimally to a targeted plastic or set of plastics. Hopefully this new material can leapfrog off of the progress and work of the composites industry. Humidity will also be a concern that requires some testing and may cause some compromise on binder selection.

    Also, 'typical' fiber properties really depend on the application. A typical aerospace carbon fiber is Hexcel IM7, which shows considerable improvement over the properties they reported in the article, and others can be a fair bit better or worse. The IM7 6k tow fiber is reported to have:
    Ultimate Tensile Strength: 5.15 GPa
    Elastic Modulus: 276 GPa []

    Sample properties of one finished product provide:
    Ultimate Tensile Strength: 2.5 GPa
    Elastic Modulus: 163 GPa []

    A few years ago the least expensive carbon fiber would sell for ~$15/lb raw material with the epoxy typically around $9/lb, and the IM7 fiber above is probably an order of magnitude more costly. I don't know what figures they used for their cost comparison, but they can't really have the whole cradle to grave process figured out at this stage anyway, so we'll see what happens when they get some material fabricated.

    There's a lot of work ahead, but this seems promising!

  • Seems to me a bacteria could be genetically engineered to eat this stuff, just like Duroplast. Could make its use in warfare untenable.
    • I disagree. The Mosquito was one of the best twin engine planes made during WWII. It was made almost entirely of wood. Wood is subject to rot, insects and other problems but for it's purpose it was the best material for the job: Non-strategic, easy to work with--they had cabinet makers making the aircraft. Sure, you don't see many Mossies remaining today but they lasted as long as the needed to.

      I think that even if a CNC-eating bacteria were to be developed, reasonable precautions could be made. I
  • by bdwoolman ( 561635 ) on Tuesday September 04, 2012 @05:11PM (#41227663) Homepage

    Paper demand is very sluggish in the developed world. The slow death (or metamorphosis) of the newspaper industry that is directly related to the digital publishing revolution is clearly responsible. The less-paper world is coming. It's coming later than many thought it would, but the paper companies are really feeling it. A friend who follows the paper industry told me that projected paper demand is a full thirty percent lower now than expected in the developed world. Not that demand is actually shrinking, it is just growing slower -- a lot slower -- than earlier trends projected. The developing world is more robust. Corporate investments in forests are by nature long-term. And there is a glut due to demand not growing as projected. Hence intensive research -- as seen in this FA -- into other ways to use pulp in quantity.

    I briefly looked for something comprehensive to make my point and found this article from Paper Age. [] It is pretty general, but the writing is on the wall-mounted tablet display.

Time to take stock. Go home with some office supplies.