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Paper Stronger Than Cast Iron 327

TaeKwonDood writes "All paper is made of cellulose, which at the nanoscale level is quite strong, but paper processing makes large, fragile fibers that break easily. Researchers in Sweden have have come up with a manufacturing process that keeps the fibers small, resulting in 'nanopaper' with over 1.6 times the tensile strength of cast iron (214 megapascals vs. 130 mPa). And since cellulose is the most abundant organic compound on the planet, it's cheap to use compared to other exotic, expensive-to-produce options — such as carbon nanotubes."
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Paper Stronger Than Cast Iron

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  • by camperdave ( 969942 ) on Monday June 09, 2008 @11:23PM (#23719371) Journal
    It's strong enough to build a ship out of... as long as you don't get it wet.
  • by Armon ( 932023 ) on Monday June 09, 2008 @11:24PM (#23719381)
    Coming next summer, the Epic battle between Robert Downy Jr. as Iron Man, and an unknown antagonists who goes by the mysterious PAPER MAN! /attempt at humor
  • by Chas ( 5144 ) on Monday June 09, 2008 @11:25PM (#23719387) Homepage Journal
    Or treatable to be fire-resistant?

    I can see a lot of uses for it even if it isn't. But I can see some fairly awe-inspiring ones if it's possible.
    • Or treatable to be fire-resistant?

      I can see a lot of uses for it even if it isn't. But I can see some fairly awe-inspiring ones if it's possible.
      Guy 1: BWAHAHAHA, BEWARE my super-robot made with nanopaper! It's stronger than steel!
      Guy 2: *lights match*
      Robot: *FWOOOM*
      Guy 1: :(
    • by phantomfive ( 622387 ) on Monday June 09, 2008 @11:40PM (#23719573) Journal
      Could be it doesn't matter for a lot of applications. Houses aren't fireproof, in fact a lot of things arent: clothes, boxes, guitars, plastic, etc. Cast Iron isn't exactly the strongest stuff around, so obviously tensile strength isn't the only important thing in a material. Apparently there is a lot research going on these days about how to make stronger paper. Some links at the bottom of the article.
      • by mazarin5 ( 309432 ) on Monday June 09, 2008 @11:47PM (#23719677) Journal
        I suddenly had an image of Japanese-style paper walls made of this stuff. I wonder how much this would cost after it becomes commonplace? Would it be a viable replacement for drywall or wood? Would it be a good insulator?

        Interesting indeed.
        • by Iamthecheese ( 1264298 ) on Tuesday June 10, 2008 @12:21AM (#23720015)
          If nothing else, it will revolutionize the packaging industry. Strong cardboard boxes are a holy grail of packaging.

          Other uses? Paper airplanes, coat it with plastic and make a really cheap fishing boat, tape that won't break, temporary floor, single-use knife, non-toxic circuit board for cheap toys... This is a breakthrough in the highest meaning of the word.
          • Re: (Score:3, Interesting)

            by DrMrLordX ( 559371 )
            Imagine what the Trabi could have been with nanopaper instead of duroplast.
          • by marxmarv ( 30295 ) on Tuesday June 10, 2008 @02:04AM (#23720763) Homepage
            Copper-laminated paper circuit boards are already cheap and available. Now if this stuff is or can be made as flexible as paper, you may have just replaced thin film in flexible circuit applications.

            I wouldn't sell it on its toxicity benefits though. The chemicals used to mask and etch pc boards are none too friendly and most paper is absorbent.

            I wonder if anyone's tried injection molding short chain cellulose yet... it's better to use carbon we have on the surface already than to mine more and bring it into the surface ecosystem to stay.
      • Re: (Score:3, Insightful)

        by Anonymous Coward

        Houses aren't fireproof

        Correction: Wood houses.

        There are enough houses, particularly in Europe, which are made mostly of bricks, concrete, and steel. (Floors, even on the second/third levels are made of poured concrete and supported by steel beams.)

        They are as close to fireproof as it gets, except perhaps the roof.
        • Re: (Score:3, Informative)

          You'd be surprised...

          In the UK at least half of all domestic construction uses timber frame for the load-bearing structure with simple block and render for the outer skin which provides none of the structural support. Come up to Scotland and practically every building less than 5 storeys high is made using a timber frame.

          The trick in making a building fireproof isn't in making the structure fireproof, but in stopping the fire from getting to the structure in the first place. That's the why every wall and ce
      • I got all my clothes before the whole "Anti-carcinogen" fad, I only wear fire retardant pajamas.
    • Re: (Score:3, Funny)

      by Ilan Volow ( 539597 )
      I understand where you're going with this, but I'd doubt that Martha Stewart would take a paper frying pan seriously.
    • by zappepcs ( 820751 ) on Tuesday June 10, 2008 @12:47AM (#23720237) Journal
      Actually, you are probably right. More porous and stronger? Sounds like a new paper towel to me. Hmmm what other paper products do we use that might benefit?

      Saturated paper products: Tar paper, sheetrock, and other products that are basically using paper to contain some other product, etc.

      Non-saturated: string spindles et al, books, food and product packaging materials, shipping materials...

      If it turns out that thicker pieces constructed with pressure or other methods, perhaps we'll finally get a throwaway computer or dvr case? Perhaps we'll find that a lot of carbon based plastics might be better created with nanopaper processes? How much oil would that save? How much cleaner could commercial enterprises become?

      There are a lot of things that paper is only just a bit less suitable than some other product that creates pollution or distributes toxins either during creation or after it's use.

      Obviously, I'm not the expert, but if this can make some of that come true it will be a very good thing.
    • Re: (Score:3, Interesting)

      by SamSim ( 630795 )

      That would make for superb irony when we reach the future of Fahrenheit 451. All the houses are fireproof, on account of being made of the very paper Montag is paid to burn...

    • by starglider29a ( 719559 ) on Tuesday June 10, 2008 @09:57AM (#23724977)
      Wrapping candy bars, USB drives and CD's to make them UTTERLY un-openable.
  • Milli-pascal? (Score:5, Informative)

    by dascandy ( 869781 ) <> on Monday June 09, 2008 @11:26PM (#23719397)
    > 214 megapascals vs. 130 mPa

    214 megapascal (singular, it's a unit) is about 1.6*10^9 more than 130 millipascal. Use your units properly.
    • The intended units were megapascals.

    • Re:Milli-pascal? (Score:5, Informative)

      by Anonymous Coward on Monday June 09, 2008 @11:40PM (#23719579)
      What's he trying to say is that those units should be MPa (capital M and capital P) for both.

      Also most steels are above 400 MPa (some as high as 1800) so this isn't that strong, in fact Aluminum alloys can reach into the 400 MPa range.

      Cast Iron (in its 2 major forms grey & white cast) is very brittle and therefore does not have good tensile strength. However compressive strength and its good vibration tolerance is why a lot of large machining equipment uses a cast iron base.
      • Re: (Score:3, Informative)

        by smchris ( 464899 )
        I can testify that cast iron is brittle from experience. I had a summer job many, many years ago drilling and tapping cast iron foot pedals for industrial equipment. We weren't allowed to toss them into the finished bin. They had to be _laid_ in the bin (a very significant fraction of the time of a unit cycle) because it was quite common for them to shatter if you tossed them four or five feet. Nonetheless, there would be many uses for this product. Perhaps cast iron wasn't the best comparison the PR g
    • by pablomme ( 1270790 ) on Monday June 09, 2008 @11:57PM (#23719793)

      Use your units properly.
      AND they should be using MebiPascals: "204 MiPa vs. 124 MiPa".

      IEC 60027-2 : making life easier for everyone since 1999.
    • Re: (Score:3, Informative)

      Also, why would they use the tensile strength of CAST iron? The tensile strength of rolled red steel is 350 MPa, and that's what is used for tensile applications, like.... almost everything. Cast iron is used for compressive purposes, because of it's ease of manufacture, and strength in compression only.
    • by pclminion ( 145572 ) on Tuesday June 10, 2008 @02:20AM (#23720855)

      214 megapascal (singular, it's a unit)

      Is that really a rule? Not one I was taught.

      After I ran 6.2 kilometer yesterday, I was feeling thirsty. So I drank 1.6 liter of water. It took 37 minute to walk back to my car. I fired it up, and saw that the engine was already 52 degree from sitting in the hot sun. I got home, and collapsed from exhaustion. I slept an entire 9 hour.

      Maybe it's a rule. I'd rather not sound like a fool though.

      • Re:Milli-pascal? (Score:4, Interesting)

        by Wyck ( 254936 ) on Tuesday June 10, 2008 @08:42AM (#23723751)

        After I ran 6.2 kilometer yesterday, I was feeling thirsty. So I drank 1.6 liter of water. It took 37 minute to walk back to my car. I fired it up, and saw that the engine was already 52 degree from sitting in the hot sun. I got home, and collapsed from exhaustion. I slept an entire 9 hour.

        After a 6.2 kilometer run yesterday, I was feeling thirsty. So I had a 1.6 liter drink of water. It was a 37 minute walk back to my car. I fired it up, and saw it already had a 52 degree engine temperature from sitting in the hot sun. I got home, and collapsed from exhaustion. I had a 9 hour sleep.

        Adjective vs. noun usage?
  • Papery (Score:5, Funny)

    by Deltaspectre ( 796409 ) on Monday June 09, 2008 @11:27PM (#23719413)
    It's just like irony but stronger
  • by Tumbleweed ( 3706 ) * on Monday June 09, 2008 @11:28PM (#23719421)
    Perfect for government documents and voting machine audit results. :)
  • 1.6 times (Score:5, Insightful)

    by Anonymous Coward on Monday June 09, 2008 @11:30PM (#23719449)

    over 1.6 times the tensile strength of cast iron
    Considering that cast iron isn't particularly renown for its tensile strength, being 1.6 times stronger isn't that impressive.
  • by Garridan ( 597129 ) on Monday June 09, 2008 @11:30PM (#23719461)
    But... cast iron has the tensile strength on the order of concrete. Which is to say, not much at all. Good job guys, you've shown that paper is about as strong as... paper! How did this get published?
  • by professorfalcon ( 713985 ) on Monday June 09, 2008 @11:32PM (#23719473)
    This is going to mess up so many games of Paper, Rock, and Scissors.
  • hang on! (Score:5, Funny)

    by H0D_G ( 894033 ) on Monday June 09, 2008 @11:36PM (#23719521)
    Wait, so paper beats scissors now?
  • Cast iron does not have much tensile strength. Looks like they cherry-picked something to compare it to that sounded impressive.
  • by dbIII ( 701233 ) on Monday June 09, 2008 @11:37PM (#23719531)
    The tensile strength of grey cast iron is fairly low because the carbon comes out in the form of graphite. That's right - the same thing that is in pencils. When you have large flakes of graphite, say a few millimetres in size, you have a fairly low tensile strength (stretch it and it breaks) and low toughness (drop it and it cracks). The compressive strength isn't so bad and cast iron is a lot easier to make than steel which is why it is still used.

    With the paper there is the advantage that small particle sizes dramaticly increase strength.

    • The tensile strength of grey cast iron is fairly low because the carbon comes out in the form of graphite.

      This all reminds me of Gibson's Virtual Light

      Nigel did work for some of the other riders at Allied, ones who still rode metal. He hadn't liked it when Chevette had gone for a paper frame. Now she bent to run her thumb along a specially smooth braise. 'Good one,' she agreed.

      'That Jap shit delaminate on you yet?' 'No way.'

      'S gonna. Bunny down too hard, it's glass.'

      'Come see you when it does.'
      The frames looked as though they'd been carved from slabs of graphite. Maybe they had, she thought; there was graphite around the paper cores in her bike's frame, and it was Asahi Engineering.

      There are already bike frames made out of graphite & epoxy, why not throw in some paper?

    • A well seasoned cast iron implement also has the advantage of being relatively non-stick without the use of teflon or anything else which tends to flake off into food or otherwise degrade, which is, in my opinion, useful.
      • Re: (Score:3, Interesting)

        by value_added ( 719364 )
        A well seasoned cast iron implement also has the advantage of being relatively non-stick ...

        Well-seasoned cast iron also has other advantages other than being non-stick (not relatively, but most definitely) that include more even and higher temperatures (for superiour browning), requiring no soap and water to clean, and being oven-safe (oven-friendly, actually) so you can cook using using any method or methods you choose.

        Then again, cast iron went out of fashion years ago when women started working in prof
    • boxes (Score:3, Insightful)

      by Quadraginta ( 902985 )
      I would guess the application of interest is shipping boxes and so forth. If you want things well-protected, increasingly important in a shipping industry that uses more robots and conveyor belts and fewer human hands every day, you need strong boxes. Probably even a modest increase in the strength of cardboard would be quite helpful, as it would reduce the fraction of the weight of a shipment that is boxing.

      It all depends, really, on whether the processing needed to create "super" paper doesn't cost mor
  • by TRAyres ( 1294206 ) on Monday June 09, 2008 @11:37PM (#23719539) Homepage
    But now it will be INDESTRUCTABLE as well!


  • cast iron? (Score:5, Informative)

    by Tmack ( 593755 ) on Monday June 09, 2008 @11:41PM (#23719583) Homepage Journal
    Really, cast iron is weak in comparison to a lot of metals. 130mPa is also the ultimate strength of human bone [], which would have made a much more interesting comparison. Cast iron isnt really used as much for anything anymore since steel is much stronger and is almost as cheap. The article's claim to replacing carbon nano tubes is a bit of an exaderation, as they have a strength of 62GPa


    • Re:cast iron? (Score:5, Informative)

      by plover ( 150551 ) * on Tuesday June 10, 2008 @01:07AM (#23720373) Homepage Journal
      Cast iron's not exactly dead. It's still good for producing relatively intricate parts cheaply. As long as you don't require high accuracy on every surface, you can have a really complex part that's only somewhat more expensive than the scrap iron that goes into it.

      Think of a thin stationary engine housing with fins to dissipate heat -- you usually don't care if the fins are within 0.25" of where they're supposed to be; as long as air can pass over them they can do their job. As far as the important surfaces, such as the ones that hold the bearings or that mate with another housing, sure, you'll have to machine those. But if you had to machine all those fins from a solid steel block, or cut a bunch and weld them all on, you'd easily spend three times the money on labor and tooling and have a part that doesn't last as long as a casting.

      There are many different alloys of cast iron, and they each have their own set of properties. All are much harder than ordinary steels, and usually have excellent wear resistance. Some alloys allow for more intricate castings. Some are easier to machine. And some, such as white iron, are extremely brittle and almost worthless in tensile strength, but can be treated to crazy levels of hardness. It all depends on your application, and in which properties you require. Steel can't simply be "dropped-in" as a replacement material. Hell, sometimes you can't even substitute ductile cast iron for malleable cast iron.

      And I wouldn't count on being able to substitute paper for cast iron, either!

  • There's already health concerns and risk with other nano technologies, what about paper? I'm around printers all day long and see a great deal of paper dust. What if there were made up of nano particles and got into the respiratory system of people?
  • ...a space elevator we can wrap fish in!
  • Do they leave shields instead of scrolls?
  • by master5o1 ( 1068594 ) on Tuesday June 10, 2008 @12:31AM (#23720125) Homepage
    Like Paper Construction Cranes?
  • Prior art (Score:3, Interesting)

    by Deadstick ( 535032 ) on Tuesday June 10, 2008 @12:57AM (#23720311)
    Jules Verne wrote of a paper-constructed aircraft in Robur the Conqueror...


  • So it isn't actually the pen that's mightier than the sword, it's what you use it on.

    • Given climatic changes I think we may want to think this one over.

      I can see someone building a skyscraper, only for the whole thing to fall over because someone has an aiming problem in an urinoir midlevel. And God help you if you want to redo the wallpaper :-).

      No! Don't us a steame .. aaaagh!

      Joking aside, interesting development. Puts the final nail into the paperless office.

      No! Aaargh! I'll stop making bad jokes now! :-)
  • by gweihir ( 88907 ) on Tuesday June 10, 2008 @03:41AM (#23721343)
    This comparison is highly suspicuous. You do not use cast iron for anything that needs tensile strenght, as it breaks too easily. Wrought iron is a whole different matter and is what is used in construction of cars, ships, girders, and the like. Cast iron in the shape of a pice of paper could easily broken by hand without tools.

    It seems aluminum alloy has about twice the tensile strength of cast iron. Ever tried to rip tinfoil? Not that difficult.

    Side note: mPA is milipascals, not megapascals.
    • Re: (Score:3, Informative)

      On the other hand, aluminum foil is basically pure aluminum, while aluminum alloys contain up to around 10% of either copper, zinc, tin, etc. Some special 7000-series alloys have tensile strengths surpassing some of the softer steels; they are however shockingly expensive and brittle (and they ring like glass when struck).

      The aluminum found in aluminum foil would never be used in aircraft construction or anything else requiring strength. While I love materials science, TFA or the researchers (whoever chose
  • Cancer. (Score:3, Interesting)

    by leuk_he ( 194174 ) on Tuesday June 10, 2008 @04:42AM (#23721769) Homepage Journal
    Note that carbon nanotubes might cause cancer []. I wonder how this paper fibers that are threated will be in the health department. Paper sounds fine, but that is the same what they thought of asbestos.
  • by Attila ( 23211 ) on Tuesday June 10, 2008 @07:26AM (#23722989)
    Anyone who has ever used a public toilet in Sweden would know that this has been in development for some time.

I've noticed several design suggestions in your code.