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Science Technology

Plastic Made From Fruit Rivals Kevlar In Strength 181

jldailey618 writes "A group of scientists from Sao Paulo State University developed a way to use the nanocellulose fibers from bananas, pineapples, and other fruits to create incredibly strong, lightweight plastics. The plastic is up to four times stronger and 30 percent lighter than petroleum-based plastics, and it rivals Kevlar — the material used in bullet proof vests — in strength."
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Plastic Made From Fruit Rivals Kevlar In Strength

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  • ... Thought that one had my name on it.
  • by cvtan ( 752695 ) on Wednesday March 30, 2011 @07:49PM (#35672878)
    The perp shot me with a gun made of pineapples, but luckily I was saved by my banana. (First or nearly first post is no guarantee of quality.)
  • What else is in it? (Score:4, Interesting)

    by cromar ( 1103585 ) on Wednesday March 30, 2011 @07:53PM (#35672926)
    The article says that one pound of nanocellulose can be used to produce 100 pounds of the plastic. So what else is in it? Maybe it's a journalistic error, but it would seem that that violates physical law...
    • Re: (Score:3, Informative)

      by TubeSteak ( 669689 )

      The article says that one pound of nanocellulose can be used to produce 100 pounds of the plastic. So what else is in it? Maybe it's a journalistic error, but it would seem that that violates physical law...

      Ever heard of an alloy?
      =1% is more than enough to effect a change in metals or plastics.

    • by Thing 1 ( 178996 ) on Wednesday March 30, 2011 @09:51PM (#35673780) Journal

      The article says that one pound of nanocellulose can be used to produce 100 pounds of the plastic. So what else is in it? Maybe it's a journalistic error, but it would seem that that violates physical law...

      I really liked the topical Married With Children response (the other half of the raisins came from Japan?), but I think the simple answer is it's a reading comprehension, or writer overly compressing the message, issue: one pound of nanocellulose is used, but it is not the only ingredient; the important sentence ends the sixth paragraph: "These fibers can be added to other raw materials to produce reinforced plastic."

      I also really liked the linked article in the fourth paragraph, about Ford exploring nanotechnology to get their vehicles' weight down. Competition will get us to the Singularity faster!

    • by mrmeval ( 662166 )

      http://en.wikipedia.org/wiki/Nanocellulose [wikipedia.org]

      Old news. This has been known since the late 70s. It's terribly energy intensive. The material costs 30MWh to produce with some methods getting that down to 1MWh but with more complex processes.

      I don't see anything that indicates an improvement in the process in that article that would make the material more cost effective or live up to the potentials mentioned in the wikipee article. It looks like the typical article meant to gather research money and it's been pi

      • by mldi ( 1598123 ) on Thursday March 31, 2011 @01:01AM (#35674902)

        http://en.wikipedia.org/wiki/Nanocellulose [wikipedia.org]

        Old news. This has been known since the late 70s. It's terribly energy intensive. The material costs 30MWh to produce with some methods getting that down to 1MWh but with more complex processes.

        I don't see anything that indicates an improvement in the process in that article that would make the material more cost effective or live up to the potentials mentioned in the wikipee article. It looks like the typical article meant to gather research money and it's been picked up because of the presentation made at the chemical groups exposition.

        As oil prices keep increasing, alternatives like this (combined with newer tech) become much more cost-effective. My question is: do these plastics degrade faster than petroleum based plastics? I have the giant garbage islands floating in the oceans in mind here.

        • As oil prices keep increasing, alternatives like this (combined with newer tech) become much more cost-effective.

          So, as we exhaust cheap energy, it becomes more cost-effective to turn to production that consumes even more energy?

          • by mrmeval ( 662166 )

            The market for all it's ills is not insane unless directed to be insane by regulation, it's customers or it's megalomaniacal boss. It's difficult to have a whole organization be insane. :(

            Without that insanity it will take prices reaching nsane levels to go to nanocellulosic material for mundane items. Unfortunately they won't be mundane items any longer as people will turn to cheaper materials. Status quo.

            It's one of those remarkable products that it's nice get noticed as there are a lot of hungry entrepre

        • by mrmeval ( 662166 )

          I don't believe any cellulosic fiber degrades faster than petroleum based ones. Even the commercially viable ones have been pretty solid.

          That island has all the free energy you could ask for in solar. It has very little weather most of the year. You should build a flotilla to go mine it.

      • And naturally, its being recycled because of the "green" impact. However, its only 1 percent "green".
    • Secret sauce?

    • It just cost a hell of a lot of energy...
      E=mc2 suggests producing a kilogram of it would require 990x(300,000,000^2)=8.9e19 joules or more than the electricity generation in the total of 2005.
  • by zill ( 1690130 ) on Wednesday March 30, 2011 @08:00PM (#35672988)
    Ring ring ring ring ring ring ring, Banana phone. (now made out of REAL bananas)
  • Industrial hemp (Score:5, Interesting)

    by narcc ( 412956 ) on Wednesday March 30, 2011 @08:01PM (#35673002) Journal

    We've been able to make all sorts of materials from plant fibers for years, including plastic.

    As an added bonus, many of those materials are both incredibly strong and bio-degradable. Take a look at hemp plastic -- one of the many reasons to support industrial hemp.

    • by Mashiki ( 184564 )

      Nah. The US doesn't like anything dealing with pot...I mean hemp. But up here in Canada, we don't mind it a single bit. In fact I usually start my day with a couple of tablespoons of hemp hearts on my cereal or oatmeal.

    • Re:Industrial hemp (Score:5, Interesting)

      by theshowmecanuck ( 703852 ) on Wednesday March 30, 2011 @08:12PM (#35673106) Journal
      When I did some work in the Philippines I had to go to a function where the president was going to attend, so went out and bought a high end barong (type of Philippine shirt). These were used in place of tuxedos (yes we wore pants too). The barong was made of banana fibre and was quite expensive (several hundred dollars at the time). I still have it. The interesting thing is that is does feel kid of plasticy and slippery. The fabric is partially see through (you wear a white tee shirt under it) and kind of stiff. Because of this, this article doesn't surprise me one bit.
      • Re:Industrial hemp (Score:4, Interesting)

        by Max Littlemore ( 1001285 ) on Wednesday March 30, 2011 @09:05PM (#35673476)

        I had a shirt made of eucalypt that was very light, plasticy feeling and hard wearing.

        The thing I found most odd about it wasn't that such a synthetic feeling fabric came from a plant, but that I live in Australia where eucalypts originate and the shirt was made in China most probably from Chinese eucalypt plantations, being the largest in the world.

        I would like to see more done with eucalypts for plastics. They are a great source of celulose and other goodies, grow quickly without needing much water and they are not a valuable food source like bananas, corn and pineapple. And there's a reason we call them gum trees.

        • by narcc ( 412956 )

          Neat. I haven't heard about eucalyptus being used this way before. Thanks for that.

        • And there's a reason we call them gum trees.

          It's because they have no teeth. Duh.

        • What about all the little Koalas!?
          • Koalas don't live in Chinese plantations. And they are very selective about which specific trees the eat.

            Oh yeah, and I prefer to call them hairy tree pigs. If you've ever heard them at night you'd know why.

            • Im just kidding. They good to eat?
              • Never tried them but I understand blackfellas wouldn't touch them and given their diet I don't think I would either. Kangaroo, snakes, goanna, croc are all good. Possum and koala not so good.
                • Ive had alligator and ostrich, both were pretty good. Im not sure how close alligator is to croc. Ive also had elk, deer, moose, and bison, but neither are really a big deal where Im from up near Canada since its local. Id actually like to eat alligator more often, but its sort of a swamp-dweller food down here in the south US where I live now so you only get it at some Cajun restaurants. Ive always wanted to try snake. BTW I don't know how you guys eat Vegemite. Tried it once, never again. Cheers buddy.
      • My father has some socks made from bamboo fibre --- they feel like cotton, and apparently also behave like it. Given how easy bamboo is to grow (i.e., it's really hard to stop it), using it for fibre seems like a really good idea.
        • This is totally off-topic, but bamboo socks are awesome. As a clothing material it's porous, sweat-wicking, and anti-microbial (reduces odor).

  • That small weight makes a big difference for swoop racers, but will it stop a slug from a tusken cycler rifle?
  • Better quiet down (Score:5, Insightful)

    by Anonymous Coward on Wednesday March 30, 2011 @08:11PM (#35673084)

    The last time someone tried to compete with DuPont with a cheap and available material, they lobbied congress to ban the material, which they did.

    I for one do not wish to have bananas, pineapples, or any other fruit be classified as a schedule I controlled substance.

    • by CBravo ( 35450 )

      Can you give a reference to this 'fact'?

    • I for one do not wish to have bananas, pineapples, or any other fruit be classified as a schedule I controlled substance.

      Hey, didn't you know, you can get high from smoking banana peals [lycaeum.org]...

      • Hey, didn't you know, you can get high from smoking banana peals

        I've never known a banana to ring out with a mellifluous tone, and even if one did I doubt it would get me high.

  • I, for one, welcome our new nano-nana overlords!

  • by macraig ( 621737 ) <mark@a@craig.gmail@com> on Wednesday March 30, 2011 @08:27PM (#35673218)

    Petroleum was once (partly) fruits, too, eh? It's not a bad thing if we can sidestep the tens of millions of years in between and do it without massive energies or pressures. Same thing goes for fuel, of course, but I'm not holding my breath for biofuels, yet....

  • by MrEricSir ( 398214 ) on Wednesday March 30, 2011 @08:34PM (#35673274) Homepage

    We already have fruit made from plastic. So why not make plastic from fruit? That way the circle of life continues indefinitely.

  • Strong or tough? (Score:5, Insightful)

    by wagnerrp ( 1305589 ) on Wednesday March 30, 2011 @08:44PM (#35673332)
    Is strong really the correct term to use here? People think of kevlar being strong because it's used to stop bullets, but they're really completely wrong. Sure, it's stronger than steel, but not as strong as fiberglass or carbon fiber. You use kevlar in armor because it is tough, toughness being defined by the area under the stress/strain curve. It can absorb more energy than any other material. If it's as strong as kevlar, well then there are plenty of other natural and synthetic fibers that are just as capable, and this is nothing impressive. If it's as tough as kevlar, well then there is something of significant interest here.
    • by toQDuj ( 806112 )

      indeed, one of the reasons to use it is the low elongation at break, and the relatively high stress at breakage. Some have suggested using spider silk for bulletproof vests, and indeed it would stop the bullet... just several meters on the other side of your body. more in the introduction of my thesis http://bit.ly/gfPdDN [bit.ly]

      • Your link looks awfully close to an attempt at trojan injection.
        • by toQDuj ( 806112 )

          this (more direct) link any better? http://orbit.dtu.dk/getResource?recordId=253339&objectId=1&versionId=1 [orbit.dtu.dk]

          • Look, the only reason I know the tricks is because of my rampant porn viewing. A strange link like that tends to lead to some download or infected image that maliciously affects your computer. Its easily removed often enough or avoided by not clicking "open", but you begin to filter links like that out from experience. Since most of / . users view porn as much or more often than I do, you should consider what I said as an attempt to help you be credibly heard. Any other view of what I said would be wrong.
  • by dbIII ( 701233 ) on Wednesday March 30, 2011 @08:47PM (#35673360)
    Kevlar is a very useful nylon-like polymer because it's tough. What the means is that it can absorb a lot of energy before it breaks. It can't hold up a lot of weight (so not strong) but if you hit it very hard it flexes instead of breaking. That is why it is useful in bullet proof vests because you want to spread the impact and absorb the energy before it gets to your body. Toughness is a function of how much things can stretch together with strength -eg. rubber with low strength and a lot of elongation can absorb a lot more energy than glass with high strength and nearly no elongation.
    By volume Kevlar is nowhere near as strong as mild steel so a 10mm diameter rod of the stuff is not going to be able to suspend anywhere near as much weight as a 10mm diameter rod of mild steel. It doesn't weigh much though so you might be able to make something out of 1kg of Kevlar that can take as much load as 1kg of mild steel.
    It's very strong for a plastic (think of nylon fishing line - it's like that but stronger) but plastics are not very strong materials unless you reinforce them with something that is such as glass or graphite fibre.
    • by toQDuj ( 806112 ) on Wednesday March 30, 2011 @10:17PM (#35673948) Homepage Journal

      Except that kevlar and other aramid fibres are almost entirely unlike nylon or dyneema. The structure is completely different, the aramid fibres can withstand high temperatures whereas the nylon fibres cannot (different chemistry), and the manufacturing process is completely different.

      Second point: the aramid fibres have a very small elongation (strain) at break, and can hold a large amount of stress. Indeed, on a per weight basis, they are "stronger" than steel, by volume, it is not so good. However, they do not exhibit much creep (but nylon does!) and do not suffer from effects of prolonged loading.

      Lastly, they do not bend well, and they cannot handle sharp edges so well because of that. Interestingly, you can get two kinds of protective vests with different weaves: one bulletproof type and one knifeproof type. the knifeproof vest is not bulletproof and vice versa.

      You may want to consider reading the introduction to my Ph.D. thesis (or its references) on this material as it appears you may be slightly misinformed. You can get it here: http://bit.ly/gfPdDN [bit.ly]

      • by dbIII ( 701233 )

        on a per weight basis, they are "stronger" than steel, by volume

        See my post above for exactly the same thing.

      • by epine ( 68316 )

        Second point: the aramid fibres have a very small elongation (strain) at break, and can hold a large amount of stress. Indeed, on a per weight basis, they are "stronger" than steel, by volume, it is not so good.

        Try a Nylon semicolon instead of the Kevlar comma. You'd already used a carborundum colon in the preceding sentence, so I know you have it in your bit kit.

        Indeed, on a per weight basis, they are "stronger" than steel; by volume, it is not so good.

    • by strack ( 1051390 )
      you talk about volume to strength ratio. no one cares about that. people care about weight to strength ratio. kevlar has a specific strength 10 times higher than that of steel. so yeah. a kg of kevlar is a hell of a lot stronger than a kg of steel.
      • I talk about strength in terms of cross sectional area because that's what strength MEANS - maximum force per unit of cross sectional area. Many people make the mistake you just did and think that kevlar, polyester, PVC, balsa wood, foam packaging etc is stronger than steel when it is not. That's why I wrote what I wrote above to try to clear up confusion like yours above.
        As an example in an aircraft they use high strength steels for landing gear parts because actual strength is more important there than
  • Bullet Proof Banana Hammocks Made Out of Bananas.

    On a serious note, a lot of 'projects' seem to come out like this one, but very few ever seem to make it to commercial scale and distribution, let alone success and continued survival. "Alternative" tech never seems to sell, quite possibly because it's 'alternative', and the big boys have enough cash to make most things go away that would cut into their profits, like that pesky cold fusion.

    • enough cash to make most things go away that would cut into their profits

      I'm not going to say that's never happened, but if it's cheaper and/or better than the existing products, why wouldn't the big boys take the huge PR benefit of being "renewable", save a ton on industrial-scale production, and leverage the advantages of their existing product distribution networks to make more money?

  • As if a trip to the electronics store wasn't frustrating enough. Once they start making clamshell packaging out of this, no one will ever be able to get anything open.
  • Now I'll need a cutting torch to get a USB thumbdrive out of its packaging.

  • Or if not, can you make a blender out of it?

  • by Animats ( 122034 ) on Thursday March 31, 2011 @12:49AM (#35674846) Homepage

    These frequent "big materials breakthrough" articles really should wait until they've been reviewed in some publication that knows something about the subject, like Chemical Engineering News. The paper, "Agro-waste nanocomposites for automotive applications" [acs.org], presented at the American Chemical Society is available. The claims there aren't as strong as the ones in the press release. Last year, the same author presented "Agro-Wastes Nanocomposites for Medical Application". Wonder what happened to that.

    The trouble with many of these "new materials" is that they have some awful flaw. This one, for example, is "biodegradable". That means it rots. That's OK for packaging, but not for parts. Then there are basic questions, like will it tolerate water? Can it be made into thread, sheet, or film? Made at a reasonable cost?

    There's been interest in finding useful things to make out of cellulose for the last century. There's so much agricultural waste around, and it would be nice to use it for something. Most of the ideas don't work out, but people keep trying.

I have hardly ever known a mathematician who was capable of reasoning. -- Plato

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