Carbon nanotube (CNT) composite fibers are readily available as a substitute for fiberglass, offering added strength and reduced weight over non-CNT fiberglass. The most common application at present is in the manufacture of lighter, stronger and longer wind turbine blades. CNT infused fiber composites allow for blade startup in lower wind speeds and extended life of turbine blades and components.
Until recently, commercially available CNT fiber composites were created by mixing CNTs with the resin and fiber. Lockheed Martin via their wholly owned subsidiary Applied Nanostructure Solutions LLC. has developed a method of growing carbon nanotubes directly on the composite fibers, increasing the density of CNTs in the composite, thus increasing the strength and electrical shielding properties of the composite. Additionally, this advanced composite has demonstrated weight savings over traditional CNT composites, and the production method is continuous and scalable. Applications for this composite include Electromagnetic interference (EMI) shielding, ballistic paneling and wind turbine blades among others.
- Nanotechnology: Composites. [Internet]. 2012 . Available from: http://www.lockheedmartin.com/us/products/composites.html
CNTs have the potential for the secondary release of hazardous materials into and in reaction with the human environment via the creation of hazardous waste in the recycling process. The recycling process for repurposing requires the use of acetone, deionized water, hydrochloric acid and nitric acid. Additionally, SWCNTs have potentially harmful pulmonary toxicology profiles similar to other Ultra-Fine Particles (UFP). Additionally, research is emerging that suggests CNTs produce mitochondrial DNA damage and increased cardiovascular plaque buildup in mice. This will likely drive more research into the effects of CNT exposure in CNT workplace environments.