Dr. Janaki R.R. Alavalapati, Dean
School of Forestry & Wildlife Sciences
3301 Forestry and Wildlife Building
602 Duncan Drive
Auburn, Alabama 36849-3418
Armando G. McDonald, Professor of Renewable Materials, Department of Forest, Rangeland and Fire Science, University of Idaho
“The effect of biochar as reinforcing filler on the properties of wood plastic composites.”
Seminar is held at 11 a.m. in Conference Room 1101 in the SFWS Building, 602 Duncan Drive, Auburn, AL.
Abstract: The focus of this study was to observe the effect of biochar as reinforcing filler substitute for high density polyethylene (HDPE) based wood plastic composites. Four fibers types: Douglas-fir (DF), Western Renewable Technologies (WRT) biochar, Amaron (AM) biochar, and Norit activated (NA) carbon were evaluated. The composites were evaluated for their mechanical properties, water absorptions, thermal and viscoelastic properties, rheological behavior, and weatherability. The NA composite melts showed the higher modulus and viscosity, indicating better melt strength. In addition, the NA composites performed the best in tensile strength (28.6 MPa) and tensile modulus (3.4 GPa). The NA composites showed lower tan δ and adhesion factor, indicating the strong interfacial interaction between carbon particles and the matrix. The softening temperature (Ts) of the composites were improved upon addition of fillers. The degree of HDPE crystallinity in the biochar and carbon composites decreased relative to the DF composites, while the thermal properties of the composites improved compared with DF composites. For the water resistance, the DF composites displayed the highest water absorption (3.7%) and thickness swell (2.9%). During accelerated weathering tests, longer exposure time increased the degree of color change and lightness, especially for the DF composite. NA and biochar composites resulted in improved photostability.
Biography: Armando McDonald is a Professor of Renewable Materials in the Department of Forest, Rangeland and Fire Science, University of Idaho (UI) with over 33 years’ experience in bioproducts and biomaterials research and development and has presented and published numerous articles. Armando came to UI in 2001 from New Zealand Forest Research, where he was a Group Leader of the Materials Discovery group. His time at UI is devoted to mainly research and teaching with some extension/service activities. He teaches classes in Biocomposites, Biomass chemistry, and Bioproducts and Bioprocess Development. Dr. McDonald has graduated eight Ph.D. students and 15 M.S. students and hosted 15 International visiting scholars in his Renewable Materials Laboratory. Dr. McDonalds’ group is currently investigating: (i) bioplastics from lignin and other waste streams, (ii) biofuels from pyrolysis of biomass, (iii) development of nanostructured Fischer-Tropsch catalysts for production of fuels, (iv) biocomposites, (v) algae conversion to fuels, (vi) biomass conversion into chemicals, (vii) torrefaction of biomass and waste, and (viii) natural products chemistry. Furthermore, Dr. McDonald also works with industry from service work to product development projects.