RESEARCH TRIANGLE PARK — Going outside his field of expertise earned a Japanese professor a scientific discovery and a trip to North Carolina.
Shuhei Nakamura teaches at Mie University near Nagoya, Japan, and studies materials to build ever smaller, more powerful electronics. Usually, he approaches the research as an electrical engineer, not a chemist, Nakamura said, but a project he was working on about four years ago demanded more.
To protect trains from catching fire, he needed a more heat-resistant polymer for paint and electrical insulation.
"So I make it by myself," he explained during Nu-Tech2010, a technology showcase in Research Triangle Park that recently presented research applications from a handful of Japanese universities to interested North Carolina investors.
With some coaching from a chemistry professor with whom he had collaborated on a fuel-cell project, Nakamura said, he and his engineering students at Mie University came up with a new polymer. It not only resists heat as well or better than existing materials, it can also be made at room temperature without using harmful organic tin compounds.
Manmade chemicals with a strong and unpleasant odor, organic tin compounds have long been used to make industrial polymers, including plastics, silicone and polyvinyl chloride, better known as PVC.
They are catalysts - enablers that bind single molecules into long chains. Organic tin compounds don't end up in the products they make, but escape during the manufacturing process or leach into landfills. At certain levels, the compounds can cause liver damage, seizures and skin burns. European Union countries consider them powerful environmental pollutants and restrict their use. Different U.S. regulators also restrict exposures in the workplace and in some products.
Finding replacements has been "a very active research area," said Wenbin Lin, a chemistry professor at the University of North Carolina at Chapel Hill. "If you don't have to use organic tin compounds, that's a huge advantage."
Nakamura's environmentally friendly silicone can be made soft as a gel or hard as rubber, and its inventor sees great potential in commercial applications.He has already had an inquiry from Henkel, a German chemical company that does business in Japan.
"What is your catalyst?" was one of Henkel's first questions, Nakamura said. But until he is granted a patent on his invention, which is expected in about a year, Nakamura won't reveal his secret sauce.