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Even Better Than Superior To Nature?

  1. Nov 22, 2005 #1
    A few months ago I linked to this development in the creation of synthetic setae far better than those of geckos: http://www.wired.com/news/medtech/0,1286,68639,00.html [Broken]

    In the time since, I've done some research, corresponded with the team leader involved with the linked research and then came up with a new idea.
    Ok, picture a rubber sheet, or eventually a flexible diamond-like carbon compound, on this sheet are setae, on the ends of the setae are spatulae, on the ends of the spatulae are carbon nanotubes, sizes ranging from 50nm or so in diameter down to 0.4nm(Allowing the majority of the spatulae's tips to be covered in nanotubes, without wasted space in between them.) Now for my idea, the carbon nanotubes end in C=C=C string hairs.
    My question is, since I can't find anything on them, are there such things as C=C=C strings? Picture carbon atoms linked together like a pearl necklace. One atom in diameter, and of any required length.
    Second question, if they exist, are C=C=C strings hydrophobic?
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Nov 22, 2005 #2


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    I doubt there would be strings of =C=C=C=C= . . . C=C=.

    There certainly is propadiene H2C=C=CH2, but there is no butatriene H2C=C=C=CH2, though there is butadiene, H2C=CH-CH=CH2.

    I would expect the chains of =C=C= are rather chemically unstable, and either form the common graphite or diamond allotropes, or perhaps fullerenes.

    See also - http://en.wikipedia.org/wiki/Allotropes_of_carbon (very limited discussion)

    Some information about carbon allotropes included - http://en.wikipedia.org/wiki/Allotropy
  4. Nov 22, 2005 #3


    Perhaps strings of Carbon[tri-bond]Carbon[tri-bond]Carbon[tri-bond]Carbon......?

    Any other way you can think of to get hydrophobic hairs smaller than 0.4nm in diameter? How much smaller?
  5. Nov 25, 2005 #4


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    One cannot do C(tribond)C(tribond)C . . . since each carbon would have 6 bonds - and that would be extremely reactive.

    Nature always tries to get to least energy, and long chains of C=C=C . . . would be unstable with respect to graphite which more easily obtained than diamond. If it were possible and easy, many folks would already be doing it.


    The carbon atom has a radius of approximately 0.22 nm, so that is the theoretical limit of a fiber - but that is one atomic diameter - and I do not see a manufacturing technique building fibers of 1 or 2 atomic diameters.
  6. Nov 26, 2005 #5
    Hmmm, ok. Thanks for the help.

    4 angstroms, or 0.4 nanometers, is the smallest known, and smallest theoretical as well, diameter of a carbon nanotube. So that's probably the smallest, stable carbon-only wire that can be done.
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