New Products From Field and Forest

by John Youngquist, Roger Rowell, and Debra Dietzman, Forest Products Laboratory, Forest Service, USDA, Madison, WI, and Stan Bean, Forest Products and Harvesting Research, Forest Service, Washington, DC (retired).

Each year, the sun creates abundant supplies of an inexpensive raw material biomass. One particular class of biomass called lignocellulosics is drawing increasing interest as a potential source of new materials and an alternative, renewable source of familiar products.

Lignocellulosics are any substances that contain both cellulose and lignin. Common examples are wood, agricultural crops and residues, and grasses. When broken down into particles or fibers, lignocellulosics provide the raw material for a wide array of products.

Potential Products

Composites. Researchers are currently studying the formation of new types of composites that combine lignocellulosics with glass, metals, plastics, or synthetic fibers. The resulting products are strong, durable, and uniform. Wood-plastic composites are currently being developed for use in building materials, such as for doors, windows, walls, and floors; reuseable packaging; and other products.

In making composites from lignocellulosics, the biobased fibers or particles can be chemically modified to produce consistent properties not achievable from the raw material alone. A major goal of this research and development is to make new materials solely from renewable resources that rival or exceed the performance of products made from nonrenewable materials.

Wood chips are the source material used to manufacture building materials from recycled wood.

Steve Schmeiding/FS M84-0128

Nowoven Mat Products. Incorporating lignocellulosics into nonwoven mats permits the creation of complex, molded shapes (such as car doors) and simple products (such as mulching material for seedlings). The technology that permits this transformation is similar to that used to make disposable diapers and other nonwoven textiles. The process starts with a mat composed of short and long fibers, such as short wood fibers and long polyester fibers. (Long-fiber agricultural plants such as kenaf can replace the polyester fiber.) The mat is drawn between two rollers and then through a needle board. The needles go into the material smoothly, but barbs on the needles catch the long fibers on the way out and pull them back through the rest of the mat. The result is a flexible fiber mat that can be combined with an adhesive, put into a press, and molded into any desired size or shape. Left into a loosely compacted form, it can be used as air or oil filters and as mulch or seeding material.

Samples of structural materials, including structural web "I" beams and wall panels, made of pulp composites. Steve Schmeiding/FS M91-0248-6

Anthony Conner, Forest Service chemist and project leader in the adhesives lab, Forest Products Laboratory, Madison, WI, views the molecular structure of adhesives.

Steve Schmeiding/FS M90-0084-17

Chemicals. Biomass is also being used to produce chemicals fora variety of industrial uses. Fast pyrolysis of wood and bark wastes, followed by chemical fractionation, produces mixtures of phenolic compounds that could replace phenol in some thermosetting resins that are used, for example, in bonding-oriented strandboard, plywood, and some particle boards.

Tom Custer, a researcher at the Forest Products Laboratory in Madison, WI, using an electron microscope to view the fiber structure of a wood sample. Steve Schmeiding/FS M90-0088-15