created over 2 years ago | Tagged:
In a real-life "back to the future" story, scientists today reported that the sustainable, environmentally-friendly process that gave birth to plywood a century ago is re-emerging as a "green" alternative to wood adhesives made from petroleum. Speaking at the 240th National Meeting of the American Chemical Society, they described development of new soy-based glues that use a substance in soy milk and tofu and could mean a new generation of more eco-friendly furniture, cabinets, flooring, and other wood products.
The new adhesive contains soy flour and an additive used to make paper towels resist water. It performs as well as conventional wood adhesives for interior products, the scientists said, and does not produce the harmful formaldehyde vapors released from traditional plywood, particleboard, and other composite products.
"Protein adhesives allowed the development of composite wood products such as plywood in the early 20th century," said Charles Frihart, Ph.D., who participated in the research project. "Petrochemical-based adhesives replaced proteins in most applications based upon cost, production efficiencies, and better durability. However, several technologies and environmental factors have led to a resurgence of protein, especially soy flour, as an important adhesive for interior plywood and wood flooring."
The scientists identified a highly promising soy-based glue composed of soy flour, a special water-resistant additive, and other modifiers. Together these ingredients form a polymer glue for interior wood products that performs as well as the existing petroleum adhesives but does not contain formaldehyde, they said.
In the future, Frihart and his colleagues plan to develop soy adhesives that are even stronger than existing ones. Soy-based adhesives currently make up less than five percent of the wood adhesive market, but Frihart expects their use to increase. The Forest Service is developing the adhesives in partnership with Ashland Hercules and Heartland Resource Technologies.