Fabrication of Specified Risk Material-based Plywood Adhesives

Vadim Y. Kislitsin1, Pooran Appadu2, Birendra Adhikari2, Mike Chae2, David C. Bressler2 and Phillip Y. K. Choi1.
1Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta, Canada.
2Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada.

Increasing demand and cost of materials and chemicals for large-scale production of binders has caused the industry to consider utilization of new resources such as agricultural bio-waste, in particular, Specified Risk Material (SRM). This material refers to the tissues of cattle that could potentially contain misfolded proteins (called prions) that cause Bovine Spongiform Encephalopathy (BSE). Canada completely banned any use of SRM in ruminant and human food chains, pet food, and fertilizer applications in 2007. As a consequence, all the SRM is being disposed of by incineration or landfilling. On average, disposal and transformational costs of SRM vary from $75 to 200$ per tonne, which translates to hundreds of thousands of dollars in expenses for the agriculture industry annually.

The purpose of this research is to add an economical value to SRM by utilizing it for value-added purposes. After being hydrolyzed at specific conditions, all the proteins including prions (if any) are broken down to peptides, which converts SRM into a non-toxic substance that potentially has excellent adhesive properties. However, the inherent hydrophilic nature of hydrolyzed peptides limits the widespread application of SRM peptides as an adhesive. Our research includes the enhancement of SRM-based peptides to improve their water resistivity and to fabricate an adhesive material for plywood manufacture. A variety of characterization methods have been used to ascertain the improvement in water resistivity of the modified proteins. The potential application of SRM-based adhesive materials in wood industries will result in more environmentally friendly and value added utilization of SRM in comparison with the existing disposal methods.