Researchers at Louisiana State University (LSU), USA, have received a $791 568 grant from the US Department of Agriculture and the US Department of Energy to examine wood or other agricultural fibres for use in composites.
The grant, awarded to the LSU AgCenter, is for research to find technologically feasible and economically acceptable solutions for using wood and other natural fibres, together with commingled waste plastics, Wu said.
Project Leader at the School of Renewable Natural Resources, Dr Qinglin Wu, said “Because of a continuing proliferation of plastic resin types, the recycling industry cannot sort out all the contaminants – making more plastic waste.”
By combining waste plastics with natural fibres to produce high-quality industrial products, the researchers hope to provide a solution for using biomass resources in composites.
The resulting fibre-reinforced plastic composites could be used to make weather-resistant products such as roofing shingles, patio furniture, decking and other structural materials. Other uses could be for automobile bumpers, dashboards and similar components, the researchers say.
Specifically, the grant will allow the research to move to a larger scale by investing in machines that can make extruded or moulded fiber-plastic materials in larger sizes and quantities. “We want to create a process that can be commercialized,” Wu said.
Wu and his research team have been combining recycled plastics with fibres such as rice straw, wood and bagasse (the fibres remaining after the juice is squeezed out of sugarcane) for several years, and have already created materials on the laboratory-scale.
For instance, the researchers have created co-polymers reinforced with natural fibres to reduce brittleness and increase strength. A new twin-screw extrusion machine in the Forest Products Development Center combines the fibres and plastics and, using a combination of 50% plastics and 50% fibres, the team can produce materials with similar handling properties as wood.
The researchers also are looking at nano particles, such as nanoclays, to improve the bonds between the plastics and the natural fibres. “The polymer molecules can then penetrate into the layered clays to form stronger bonds, leading to enhanced composite properties,” Wu said.
“The bond between wood and plastic is not a true chemical bond but a physical bond. We’re looking at nanotechnology using nanoclays with a new generation of coupling agents to create chemical bridges or bonds between them. The agents attach with chemical bonds to both the plastics and the wood fibres. Then their chemical properties create a stronger composite material,” he continued.
The next step is to acquire an industrial-sized, twin-screw extrusion machine to evaluate different formulations and create testing samples.
For further information, contact: Dr Qinglin Wu, Louisiana Forest Products Development Center, School of Renewable Natural Resources, Room 107, Renewable-Natural-Resources Building, Louisiana State University, BR 70803-6202, USA; tel: +1-225-578-8369; fax: +1-225-578-4251; E-mail: wuqing@lsu.edu; or: qwu@agcenter.lsu.edu; Internet: www.rnr.lsu.edu
Click here to return to the Performance Materials Net website.
