Mr university of witwatersrand johanesburg, Gauteng, South Africa
Abstract: The canola meal (the remnant after oil extraction from the canola seed) contains about 36 – 39% (8.5% moisture basis) and can be used as a low-value feed for the animals. Moreover, its protein content is currently exploring other applications such as in adhesive technology and it can be used as an alternative to the widely used formaldehyde-based adhesives. Canola proteins isolates (CPI) as adhesives have many unique properties such as ease of handling, low cost, low pressing temperatures, and the ability to bind wood with relatively high moisture content. On the other hand, it has relatively low adhesion strength and low water resistance which are the major drawbacks. This study will address these issues by modifying CPI adhesive with carbon nanotubes (CNT). CNTs are one of the most encouraging strengthening nanofillers with extraordinary tensile modulus and strength, it has been proven to significantly improve the physical and mechanical properties of the nanocomposites. Generally, this study will intend to improve the water resistance and adhesive strength of the CPI adhesive by incorporating different concentrations of the CNT into the protein matrix.
This study comprises two parts: incorporation of CNT and functionalized CNT (FCNT) into the CPI matrix. Incorporation of CNT at 1% (w/w) enhanced the adhesive strength from 5.98, 1.80, and 5.42 to 9.20, 5.64, and 7.44 at percentage increments of 53.85, 213.33, and 37.27% for dry, wet, and soaked strength respectively. The presence of the carbonyl group in the CNT after purification as well as the polyvinylpyrrolidone (PVP) helped to attain this improvement in water resistance and adhesion. functionalization of the CNT greatly improved the shear strength at 1% FCNT concentration to 10.62, 8.10, and 8.13 at 77.59, 350, and 50% increase for dry, wet, and soaked strength respectively.
