On a blogger roundtable conference call with Dr John Parmentola, he mentioned that the MIT Institute for Soldier Nanotechnologies is able to grow single strands of carbon nanotubes to a length of one foot (30 centimeters) and that they believe that 1 meter lengths will be possible shortly This is longer than the length reported by others:
In 2004, University of California scientists working at Los Alamos National Laboratory in collaboration with chemists from Duke University have recently grown a world record-length four-centimeter-long, single-wall carbon nanotube.
The Conference agenda will focus on the following seven areas:
-Quantum Information Science
As previously noted millimeter and 2 centimeter long carbon nanotubes were already starting to show that a lot of the molecular strength of carbon nanotubes was being created in larger rope. The new army/MIT results should show even better strength at large scales. Hopefully data and details will be published soon.
The longer carbon nanotubes should definitely bring space elevators and other applications closer to reality. The longer strands should keep the strength of the carbon nanotube better and be easier to form into the thousands of kilometers of a space elevator. Still need to wait until about 2015 for the thousands ton/year carbon nanotube factories. The optimistic path for this is 2020 at the earliest and there are non-trivial climber and other system issues.
A space elevator site is tracking the progress of carbon nanotubes toward the creation of suitable space elevator tethers.
In recent documents by other researchers:
In 2008, 40 GPa g/cc from Sparse (Carbon nanotubes) CNT Composite was made.
“The extraordinary reinforcing efficiency of single-walled carbon nanotubes in oriented poly(vinyl alcohol) tapes”, Wang et al. IOP Nanotechnology vol. 18 –
inferred strength of SWNTs from a 1% CNT reinforced plastic tape.
“High-Performance Carbon Nanotube Fiber”, Krzysztof Koziolet al, Science Magazine, 2007 – Measurement of the strongest of a sample of mm-long pure aggregated carbon nanotube fibers.
Goal 2010, 35 GPa g/cc for 1000 km x mm
Minimal value for Space Elevator ribbon, Taper Ratio=6.3 with 33% safety factor.
Comparative Ribbon Mass = 4.6 – May require more efficient power system.
Goal 2011, 50 GPa g/cc for 1000 km x mm
Basic value for Space Elevator ribbon, Taper Ratio=3.5 with 33% safety factor.
Comparative Ribbon Mass = 2.0
Goal 2012, 80 GPa g/cc for 1000 km x mm
Desirable value for Space Elevator ribbon, Taper Ratio=2.5 with 50% safety factor.
Comparative Ribbon Mass = 1.0