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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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  • by TubeSteak ( 669689 ) on Wednesday March 30, 2011 @08:08PM (#35673056) 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...

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

  • 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.
  • Re:Better quiet down (Score:5, Informative)

    by Ambassador Kosh ( 18352 ) on Wednesday March 30, 2011 @08:52PM (#35673386)

    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.

  • Re:Better quiet down (Score:2, Informative)

    by Anonymous Coward on Wednesday March 30, 2011 @09:53PM (#35673794)

    Not only does it have an extremely low THC content, but it also contains another cannabinol (I can't remember the name) that actually prevents you from getting high from THC.

    Another big argument is that if industrial hemp were to be legalized, farmers could easily conceal marijuana within industrial hemp fields. This is very far from the truth. Industrial hemp and marijuana plants will cross pollinate (even if the fields are miles apart). The cross pollination renders the marijuana completely useless as a drug. You would end up with a field of industrial hemp, and a field of marijuana that has no value on the drug market and is less useful than industrial hemp for practical purposes.

  • 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: []

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