Stanford University researchers have developed a synthetic wood substitute that may one day save trees, reduce greenhouse gas emissions and shrink landfills.
The faux lumber is made from a new biodegradable plastic that could be used in a variety of building materials and perhaps replace the petrochemical plastics now used in billions of disposable water bottles.
"This is a great opportunity to make products that serve a societal need and respect and protect the natural environment," said lead researcher Sarah Billington, an associate professor of civil and environmental engineering.
In 2004, Billington and her colleagues received a two-year Environmental Venture Projects (EVP) grant from Stanford's Woods Institute for the Environment to develop artificial wood that is both durable and recyclable. The research team focused on a new class of construction material called biodegradable composites, or "biocomposites"-glue-like resins reinforced with natural fibers that are made from plants and recyclable polymers.
Billington's group began by testing a number of promising materials. The best turned out to be natural hemp fibers fused with a biodegradable plastic resin called polyhydroxy-butyrate (PHB). "It's quite attractive looking and very strong," said EVP collaborator Craig Criddle, a professor of civil and environmental engineering. "You can mold it, nail it, hammer it, drill it, a lot like wood. But bioplastic PHB can be produced faster than wood, and hemp can be grown faster than trees."
The hemp-PHB biocomposites are stable enough to use in furniture, floors and a variety of other building materials, he added. To degrade, it must be kept away from air-e.g., buried in a landfill-because its decomposition depends on microorganisms that live in anaerobic environments.
"The ideal is to have nice, stable material when it's being used," Criddle explained. "But when it's out of use, it goes to a landfill, d
|Contact: Mark Shwartz|