Xinwei Wang and his research team at Iowa State University have found that spider silk is an outstanding heat conductor, which could lead to new nature-based applications in technology and manufacturing. The stretchy and strong substance was found to conduct heat 800 times better than any other organic material.
Wang, an associate professor of mechanical engineering who studies thermal conductivity, ordered eight spiders known as golden silk orbweavers to find out whether their silk could effectively transfer heat. The team discovered that spider silk (particularly the draglines that anchor webs in place) conducts heat better than most materials, even very good conductors such as silicon, aluminum and pure iron. It conducts heat 1,000 times better than woven silkworm silk and 800 times better than other organic 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," Wang said.
Whereas most materials lose thermal conductivity when they’re stretched, with spider silk it increases even further. Stretching it to its 20% limit was found to increase conductivity by 20%. These findings could lead to spider silk being used to create flexible, heat-dissipating parts for electronics, better clothes for hot weather, bandages that don’t trap heat and lots of other everyday applications.
