Vikash Ghildiyal
PhD Student, University of Canterbury
Vikash Ghildiyal is currently a PhD student in the School of Forestry at the University of Canterbury in New Zealand. He enrolled as a doctoral student in April 2020. His PhD research attempts to eliminate or reduce the drying defects of wood and by that industries can use such timber for high-value products. This is crucial because utilising plantation-grown timber is often restricted to low-value pulpwood as the drying of timber without defects is challenging. He chose to study at the University of Canterbury to broaden his research experience in wood science, explore technologies and options to improve drying of fast grown timbers.
Vikash’s research interest to date has mainly focused on quality enhancement of wood and finding appropriate technology for adding value to non-durable plantation timbers. Vikash specializes in wood technology and has a broad knowledge of wood science, including timber drying technologies, wood composites, wood anatomy and thermal modification of wood.
Vikash completed his Master's degree in Wood Science and Technology in 2019 at the Forest Research Institute (FRI) Dehradun, India. His master’s dissertation was entitled Effect of chemical pre-treatment on physical and mechanical properties of thermally modified wood. Prior to that, he got his Bachelor degree in Forestry (Honours) in 2017 at the College of Forestry, India.
Effect of Chemical Pre-treatment on Physical & Mechanical Properties of Thermally Modified Wood
Tues 10 Nov, 14:25 – 14:45
Chemical pre-treatment and thermal modification (TM) were combined in order to improve the physical properties of Melia dubia and Hevea brasiliensis. The objective of the study was to investigate the effect of different chemical pre-treatments on dimensional stability, equilibrium moisture content (EMC), water repellent efficiency, colour, pH and the mechanical properties of thermally modified wood. For this purpose, three chemical combinations, maleic anhydride (MA), citric acid (CA) + maleic anhydride and boric acid (BA) + NaOH + maleic anhydride, were used to pre-treat wood samples, followed by subsequent heat treatment under a vacuum at 180oC for 3 hrs. The physical and mechanical properties of treated wood samples were evaluated.
Thermal modification of wood with chemical pre-treatment (the combined treatment) improved the dimensional stability and reduced the degree of strength loss as compared to thermal treatment without chemical pre-treatment. The equilibrium moisture content (EMC) of the thermally modified wood was lower than the unmodified wood; however, the percentage of reduction in EMC was greater in thermally modified (TM) wood with chemical pre-treatment than TM Wood without pre-treatment. Among chemical combinations, TM wood samples pre-impregnated by MA and CA+MA had more improved properties than wood samples pre-treated with BA+NaOH+MA. The colour of specimens changed from light yellowish brown to dark brown. No defects due to thermal modification were observed. No appreciable change in density was observed in the TM samples pre-treated with chemicals due to reduction in mass loss during thermal treatment. The findings suggest a synergetic effect of MA and CA+MA treatment with thermal modification and may provide an opportunity to achieve a maximum benefit of thermal modification even at less severe conditions (low temperature and less residency time).