New materials versus conservative viewpoints
"What is the modulus of elasticity of a carbon nanotube?" That's the question I was confronted with today in a presentation I made to some university faculty about future applications of nanomaterials.
I explained that the elasticity is determined by the configuration of the nanotubes. The questioner insisted that materials have well-defined elastic properties that can't be altered. I said that's true of conventional materials like wood, steel and glass, but nanotechnology enables us to design materials in new ways and define properties like elasticity (and strength, conductivity, absorption, and much more).
But this faculty member just couldn't get beyond the conventional wisdom that materials have inherent, unalterable properties we have no control over. Conservative, conventional viewpoints like his will make life interesting for anyone looking to implement new nanomaterials with unconventional properties in the marketplace. Nanomaterials just don't do what we're used to. And no matter how remarkable their properties may be, their application will face resistance from those who say, "It can't be done!"
I’m going to side with the fossilised faculty member on this one… the elastic modulus of a material doesn’t actually depend much on configuration, because it’s basically set by the density of bond energy of the material. Strength, though, is a different issue. That’s why the modulus of carbon nanotubes isn’t so different to the modulus of ordinary carbon fibre (carbon fibre typical modulus is 230 GPa, nanotubes maybe a bit more than 1000 GPa) – the number of SP2 carbon-carbon bonds per unit volume is pretty similar. They can in principle be very much stronger, though, (200 GPa against 3.5 GPa), because strength really comes from how perfect the structure is. On the other hand, this also means that the strength deduced from a single nanotube in a microscopic experiment is likely to be very different (much bigger) from the strength you’d achieve in a nanotube rope. Nanomaterials are very exciting, but they don’t rewrite the rules of materials science.
November 8th, 2006 at 8:16 amBut, despite my last comment, your general point – that there’s a lot of conservatism about about materials choice, is certainly true.
November 8th, 2006 at 8:27 amThanks, this is one of the best things about a blog – the opportunity to learn and discuss. No one in our faculty meeting had the expertise to debate the details of nanotube elasticity, but when you reach out through the internet, you instantly get global debate and global learning.
November 8th, 2006 at 11:49 amWell my opinion is that faculty member just couldn’t get beyond the conventional wisdom that materials have inherent, unalterable properties we have no control over. Conservative, conventional viewpoints like his will make life interesting for anyone looking to implement new nanomaterlals with unconventional properties in the marketplace.
November 10th, 2006 at 4:07 pmNew materials aren’t always the best solution. Some times this is a hoax and it doesn’t work like the old remedies. Newer is not always better!
June 21st, 2007 at 8:45 amConservatory stuff is a way of living too. It’s a viewpoint that some people do not want to change. Mostly they do not like any change in their life and do not apreciate technology. cheap online pharmacy
June 29th, 2007 at 12:03 pm