The AEWC Center’s  state-of the-art, 68-foot-long extrusion system combines fibers with polymers (plastics) and can be used to make many useful components for products, such as doors, flooring, walls, decking, fencing, and moldings. Its acquisition will enable the Center’s researchers to commercially develop the next generation of fiber/polymer-composite construction materials, and it is available to assist manufacturers in researching/developing new products or enhancing existing product lines. 

 

The Woodtruder™ can process fibers from sawdust, wood (both hard- and softwoods), sisal, rice husks, coffee shells, flax, peanut shells, recycled car tires, and many other materials.  These are combined with such plastics as polypropylene, High-Density Poly Ethylene (HDPE), and Poly Vinyl Chloride (PVC), which are variously found in many consumer goods such as milk jugs, house siding and plumbing materials. Work is also underway examining the processing of wood fiber with engineering thermoplastics.

 

AEWC researchers have the expertise and facilities to investigate and determine the best combinations of fibers and polymers for a given application. Among the Center’s nine discrete laboratories are two dedicated to polymer/interface science and microscopy. These areas are equipped to lay the theoretical foundation for prototype development.  Each new material then produced by the Woodtruder™  will face strenuous evaluation in the Center, like being repeatedly stressed to evaluate durability and being exposed to the equivalent of years of ultraviolet radiation, moisture and freeze-thaw cycles.

 

The Woodtruder™ includes twin- and single-screw extruders, a blending unit, a computerized blender-control system, a die tooling system, a spray cooling tank with driven rollers, a traveling cut-off saw, and a run-off table. As processing begins, fiber is placed into the unit’s fiber feeder and dried within. Meanwhile, separate from the fiber, the plastics are melted.  This separation ensures that fibers will not be burned during plastics melting and that the melted plastic will encapsulate the fibers completely.  These materials are then mixed, and any remaining moisture or volatiles are removed by vacuum venting. Next, the materials are shaped in one of three available dies, cooled in the conveyor spray tank (which allows the new composite product to be cooled and pulled without stress), cut to the desired length and collected on the run-off table. 

 

Purchase of the Woodtruder™ was enabled in part by grants from the National Science Foundation, US Department of Agriculture and the Maine Technology Institute.  If your organization is interested in researching a new product or enhancing an existing product line, contact us at (207) 581-2846 or contactaewc@umit.maine.edu. 

Material Property Testing Capabilities at UMaine-AEWC for Wood Plastic Composites

 

The AEWC Center performs a variety of ASTM Standard tests, as well as custom tests. The staff consists of full-time, dedicated personnel supported by supervised graduate/undergraduate students. This flexible staffing arrangement enables the Center to provide quick turnarounds on routine testing. Frequently, one-week service is available for common tests. Examples of ASTM Standard tests performed at the AEWC Center are listed below.