Rice Board Development for Rice Straw Based Construction Panels, 2014


Project Leader

Joseph P. Greene, professor, Dept. of Mechanical Engineering and Manufacturing Technology, CSU Chico

This project developed composite boards made from rice straw, walnut shells, and PHA, a biobased plastic binder. These composite boards possess properties that rival traditional particleboard without toxic volatile organic compounds (VOCs).
With a compression mold process, rice straw was combined with walnut shells and a biodegradable plastic binder to create sproting pigeons (above) and composite boards (below).

Rice straw obtained from a local farmer was mixed with walnut shells and PHA plastic in a twin-screw extruder to produce plastic pellets. After varying the amount of rice straw in the mixture, successful pellets were made with 10% rice straw, 40% walnut shells, and 50% PHA. A compression mold was then used to successfully produce plastic parts.

Biodegradable plastic sporting pigeons like those used in skeet shooting were also manufactured with the compression mold. This demonstrated how the process could be used to investigate various rice straw-PHA recipes for composite materials. The biodegradable sporting pigeons displayed a similar flight pattern to traditional clay pigeons but were more costly to manufacture.

Laboratory testing also demonstrated that the rice straw, walnut shell, PHA mixture would fully biodegrade in conditions found in nature.

This research demonstrated that producing biocomposites for construction panels is technically feasible with the compression mold process. However, the economic feasibility of construction panels produced with rice straw, walnut shells, and PHA is not favorable because of the high cost of PHA resin.

More research could develop a new type of insulation panel for construction that would include a hollow section with two closeout panels made from PHA and rice straw.