Most of the research I’ve seen on spider silk has focused on its strength not its thermal conductivity. From the March 5, 2012 news item on Nanowerk,
Xinwei Wang had a hunch that spider webs were worth a much closer look. So he ordered eight spiders – Nephila clavipes, golden silk orbweavers – and put them to work eating crickets and spinning webs in the cages he set up in an Iowa State University greenhouse.
Wang, an associate professor of mechanical engineering at Iowa State, studies thermal conductivity, the ability of materials to conduct heat. He’s been looking for organic materials that can effectively transfer heat. It’s something diamonds, copper and aluminum are very good at; most materials from living things aren’t very good at all. …
What Wang and his research team found was that spider silks – particularly the draglines that anchor webs in place – conduct heat better than most materials, including very good conductors such as silicon, aluminum and pure iron. Spider silk also conducts heat 1,000 times better than woven silkworm silk and 800 times better than other organic tissues.
The March 5, 2012 news release from Iowa State University provides this detail,
The paper [about the discovery, “New Secrets of Spider Silk: Exceptionally High Thermal Conductivity and its Abnormal Change under Stretching” – has just been published online by the journal Advanced Materials] reports that using laboratory techniques developed by Wang – “this takes time and patience” – spider silk conducts heat at the rate of 416 watts per meter Kelvin. Copper measures 401. And skin tissues measure .6.
“This is very surprising because spider silk is organic material,” Wang said. “For organic material, this is the highest ever. There are only a few materials higher – silver and diamond.”
Even more surprising, he said, is when spider silk is stretched, thermal conductivity also goes up. Wang said stretching spider silk to its 20 percent limit also increases conductivity by 20 percent. Most materials lose thermal conductivity when they’re stretched.
That discovery “opens a door for soft materials to be another option for thermal conductivity tuning,” Wang wrote in the paper.
And that could lead to spider silk helping to create flexible, heat-dissipating parts for electronics, better clothes for hot weather, bandages that don’t trap heat and many other everyday applications.
Here’s a look at one of Wang’s Golden Silk Orbweavers,
Given that global warming is increasingly described as a certainty, (Simon Fraser University [located in Vancouver, Canada] March 4, 2012 news release,
Warming of 2 degrees inevitable over Canada
Even if zero emissions of greenhouse gases were to be achieved, the world’s temperature would continue to rise by about a quarter of a degree over a decade. That’s a best-case scenario, according to a paper co-written by a Simon Fraser University researcher.
New climate change research – Climate response to zeroed emissions of greenhouse gases and aerosols — published in Nature’s online journal, urges the public, governments and industries to wake up to a harsh new reality.
“Let’s be honest, it’s totally unrealistic to believe that we can stop all emissions now,” says Kirsten Zickfeld, an assistant professor of geography at SFU. “Even with aggressive greenhouse gas mitigation, it will be a challenge to keep the projected global rise in temperature under 2 degrees Celsius,” emphasizes Zickfeld.
The geographer wrote the paper with Damon Matthews, a University of Concordia associate professor at the Department of Geography, Planning and Environment.
This discovery about spider silk and its possible applications is very welcome.