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Plastic Made From Fruit Rivals Kevlar In Strength

Posted by samzenpus on from the protecting-yourself-with-fresh-fruit dept.

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."

12 of 181 comments (clear)

  1. What else is in it? by cromar · · Score: 4, Interesting

    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...

    1. Re:What else is in it? by mldi · · Score: 4, Interesting

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

      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.

      --
      If you aren't suspicious of your government's actions, you aren't doing your job as a responsible citizen.
  2. Re:Officer! by Mister+Transistor · · Score: 4, Funny

    But what if he comes at you with a Pointed Stick?

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    -- You are in a maze of little, twisty passages, all different... --
  3. Banana phone by zill · · Score: 4, Funny

    Ring ring ring ring ring ring ring, Banana phone. (now made out of REAL bananas)

  4. Industrial hemp by narcc · · Score: 5, Interesting

    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.

    --
    Required reading for internet skeptics
    1. Re:Industrial hemp by theshowmecanuck · · Score: 5, Interesting

      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.

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      -- I ignore anonymous replies to my comments and postings.
  5. Better quiet down by Anonymous Coward · · Score: 5, Insightful

    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.

    1. Re:Better quiet down by Ambassador+Kosh · · Score: 5, Informative

      The material they banned was industrial hemp. They made it illegal to grow it under the guise of going after marijuana. Even though you could set an entire field of industrial hemp on fire and not get high they still managed to get it and marijuana covered under the same law and banned.

      --
      Computer modeling for biotech drug manufacturing is HARD! :)
    2. Re:Better quiet down by Nyder · · Score: 5, Insightful

      The material they banned was industrial hemp.

      Technically, no. Your pothead buddy claimed that DuPont got hemp banned - a favorite lie of hippies and other assorted idiots. Also, industrial hemp isn't technically banned, even in the US - you can get a permit to grow it (it's just really hard to get one).

      They made it illegal to grow it under the guise of going after marijuana. Even though you could set an entire field of industrial hemp on fire and not get high they still managed to get it and marijuana covered under the same law and banned.

      That's a bit of a red-herring. Nobody ever suggested you could smoke hemp - the issue was that hemp fields made the ideal hiding spot for pot cultivation. Right now they get hidden in corn-fields and such, but tend to be relatively easy to spot from the air; you could grow millions of dollars worth of marijuana in a hemp field, and nobody would know unless they did a detailed ground-level inspection.

      Note that I'm generally in favor of legalizing marijuana - I'm just apposed to lies and distortions.

      Not sure what planet your from, but nothing is banned.

      It's a controlled substance, hence you can get a license to grow it. Industrial hemp, or medicial marijuana. I repeat for you, a non stoner, who don't know exactly what you are talking about, NOTHING GOT BANNED.

      When they got "industrial hemp" and "medical marijuana" changed into a controlled substance, they (being the corporation who just got the chemical formula's from germany, as part of WWI reparitians.), because plastic would NOT compete with the low cost and usuablility of hemp at the time. They purposely made it seem that it was marijuana they were trying to get contolled, when it was actually hemp they wanted out of the picture.

      You an find all the info, include actual copies of official documents on how this happened here: http://www.jackherer.com/thebook/

      Here's online hosting of the book: http://www.onlinepot.org/grow/jackherer.htm

      I have nothing to do with those sites or the book. I'm just an american who's tired of the lies and bullshit. And corporation being treated like they are the rich, since they rarely, and i mean, rarely get in trouble for the shit they do.

      Oh, and i like to point out, yes, it was Dupont. So those hippies and other idiots who you think lie (probably because they are stoners), aren't. In fact, your the idiot now, but then, we knew that from your post. thanks for letting me share the real story.

      --
      Be seeing you...
  6. Strong or tough? by wagnerrp · · Score: 5, Insightful

    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.

  7. Kevlar is not really very strong - it's tough by dbIII · · Score: 5, Informative

    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.

    1. Re:Kevlar is not really very strong - it's tough by toQDuj · · Score: 4, Informative

      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

      --
      Every experiment which ends in a big bang is a good experiment.