Soy-Based Adhesives Mussel Out Formaldehyde to Meet New Regulations
A decade ago, the International Agency for Cancer Research reclassified formaldehyde from a suspect carcinogen to a known carcinogen. With United Soybean Board (USB) support, Kaichang Li, an associate professor of wood science and engineering at Oregon State University, developed a soy-based formaldehyde-free resin that bonded wood like a mussel to a wet rock.
The technology was commercialized, resulting in the sale of more than 50 million formaldehyde-free plywood panels under the brand PureBond®
New rules proposed by the Environmental Protection Agency (EPA) are giving researchers and manufacturers an even greater incentive to think soy. The proposed EPA rules set limits on how much formaldehyde may be released from engineered woods. The rules cover hardwood plywood, medium-density fiberboard, particleboard and finished goods containing urea-formaldehyde (UF)that are sold, supplied, offered for sale or manufactured in the United States or those imported into the country. This covers products ranging from wood paneling and home furnishings to glues, pastes, antibacterial items, shampoo, paper towels, paper stickers, phenolic resins and urea plastics used to make things like buttons and shoes.
A second proposal establishes the requirement of a third-party certification to ensure manufacturers of composite wood products meet Toxic Substances Control Act (TSCA) formaldehyde-emission standards. The emission standards are identical to those currently in place under the California Air Resources Board Airborne Toxic Control Measure.
The Science of Soybeans
Unlike petrochemical-based wood adhesives,soy-based formulations reduce the release of volatile organic compounds. Soy flour has also proven to be an ideal raw material for making wood adhesives because it is abundant and usually costs less than petrochemicals. The relatively low cost of soy meal/flour versus petrochemical-based products has added value for manufacturers.
Although urea and phenol formaldehyde have not been completely replaced by soy in all wood adhesives, even a partial replacement can represent large cost savings. As concerns about environmental exposure to formaldehyde continue to surface, cost-competitive, versatile soy-based wood adhesives are the natural choice in adhesive formulations. To learn more about new soy-based adhesives for wood, check out the 2014 Soy Products Guide at www.SoyNewUses.org.
Biobased Solutions is the flagship newsletter of USB New Uses, covering advances in soy research and development. Each issue transmits electronically every two months and highlights four stories in soy technology and soy-based product success. To subscribe to Biobased Solutions, contact Deborah Dugan at Deborah.Dugan@osbornbarr.com.