Ultra-Strong Nanotube Composites

TheMatt writes "In a story that makes you say "Cool!", Nicholas Kotov and co-workers have created a nanotube composite material six times stronger than carbon-fiber composites. Their final product is a crosslinked material which appears to be just as strong as silicon carbide and tantalum carbide!"

Comments

Dear god!

[Snafoo]

Not...tantalum carbide...?

Re:No big uses soon...

[Charlton Heston]

Hard is relative. For example, glass is quite hard and brittle, but anyone who has handled a very large pane of glass knows that there is some small amount of flexibility there. Fiber optic cables are also famous for this. Glass fibers, yet the cable has to be flexible enough to lay in a trench.

A space elevator would be very long, and over that length it would have a lot of flexibility. I'd say that this stuff is quite promising.

How do you work with it?

[Gerry Gleason]

Obviously this is still at a research stage, but I have to wonder what will be involved in making structures out of it. The alternate dipping process sounds like a bit of a hack, but it probably can be adapted for creating macro structures. There was a time when carbon fibers were so exotic that you weren't allowed to use them in American Cup yachts, and now it's everywhere. I wonder if you could combine the two components by spraying them from seperate nozzles, or something. Then maybe you could coat a mold with the componite much like they spray chopped strand and poly resin into boat molds.

They don't give much detail on anything. They seem to be saying the material is both strong and stiff, but you might be able to play with the properties

Re:No big uses soon...

[Drishmung]

'strong' is a much overused word, and pretty meaningless without significant qualification. Which is stronger: Balsa wood or Teak? OK, so when was the last time you made a model plane out of teak then?

Materials have the following attributes (and others of course):

• brittle/tough (glass vs steel)
• elastic/inelastic (aka stiffness)
• isotropic/anisotrpic
• density
• tempera ture stability
• chemical stability (resistance to corrosion)
• cost of raw material
• cost of manufacture
• hardness

Now, stiffness is one of the important ones. High Young's modulus (stiffness) good, low Young's modulus bad. Stiff and light is better; stiff, light and tough really attracts attention.

For a very readable introduction to this, I recommend The New Science of Strong Materials (or why you don't fall through the floor) by J.E. Gordon, also his Structures.

Ultra strong girls blouses?

[Noodlenose]

Cool! Would that mean you could finally wear the equivalent of a mithril-vest for slashdot: A troll - proof undergarment?

Re:All the data you can't understand

[florescent_beige]

The notation they are using is (resin-type/fiber-type)subscript-number-of-layers so ((PEI/PAA)(PEI/SWNT)5)8 means one layer of polyethyleneimine and polyacrylic acid followed by 5 layers of PEI and Single Wall Nano Tubes with the whole shebang repeated 8 times for a total of 48 layers.

Checking out the stress-strain curves, the peak is around 160 MPa. A typical modern graphite composite might give you 4 or 5 times higher than that. It just goes to show that high fiber properties are just a portion of the final composite strength.

Another thing I notice about the stress strain curves is the non-linearity. It looks like there is some internal damage maybe happening in the material before failure. This is a concern for repeated loading (fatigue).