Clemson researchers turn tree byproduct into foam.

Today's trees maynot only be tomorrow's kitchen tables and plywood.

According to Clemson University researchers, they could also transforminto a sustainable alternative to the foam used in car seats and in the insoles of shoes.

AtClemson University'sCenter for Manufacturing Innovation, researchers met Wednesday to demonstrate how they can reconfigurelignin, a cocoa powder-like wood-processing waste product, into polyurethane foam without the use toxic chemicals.

The process usually takes about three days, according to the researchers, who have developed the method in their Greenville Clemson Composites Center lab.

The powder must be dissolved in carbonate, precipitated with acidified water and then dissolved into another carbonate. In other words, the powder becomes a cake, is then left out to dry and becomes a powder again.

Once poured into a mold with a vegetable-oil curing agent, solvent, catalyst and foaming agent concoction, the substance bubbles and rises into a disk that, once baked for 12 hours at 150 degrees, comes out at about the size of a silver dollar.

"It happens really quickly," James Sternberg, a senior scientist on the Clemson research team, said in a news release. "You've got to get it all together and then take the stir bar out and put it in the oven. There is a little bit of an art to it."

The project began its life as part of Sternberg's dissertation when he left his job as a high school chemistry teacher four years ago to pursue a Ph.D. under Srikanth Pilla, the founding director of the Clemson Composites Center and current leader of the research group.

At the time, Sternberg's cohorts had no idea that they would end up creating the foam, something the team calls invention nonisocyanate polyurethane foam, or NIPU foam for short.

Traditional polyurethane foams contain isocyanates, which can spur eye irritation, nasal congestion, throat soreness, cold-like symptoms, wheezing and severe asthma attacks, according to the National Institute for Occupational Safety and Health.

"The core advantage of NIPU foam is replacing the really toxic part of making polyurethanes," Sternberg said in the release. "When you...