Friday, March 09, 2012
Spider silk a superb heat conductor
TG Daily reports: [edited]
Spider silk conduct heat as well as metals do, an Iowa State University professor has discovered.
Indeed, spider silk - especially the draglines that anchor webs in place - is a better thermal conductor than silicon, aluminum and pure iron, and 800 times better than other organic tissues. It conducts heat at the rate of 416 watts per meter Kelvin, compared with 401 for copper and 0.6 for skin tissues.
"This is very surprising because spider silk is organic material. For organic material, this is the highest ever. There are only a few materials higher - silver and diamond."
The reason for spider silk's unusual heat-carrying properties, says Wang, is its defect-free molecular structure, including proteins that contain nanocrystals and the spring-shaped structures connecting the proteins.
Spider silk could be used to help create flexible, heat-dissipating parts for electronics, better clothes for hot weather, bandages that don't trap heat and many other everyday applications.