Effect of tung oil and zirconia powder surface treatment on the heat resistance of bamboo

Abstract

The application of bamboo has increased significantly over the years, and it is more than ever being viewed as a promising source of sustainable materials because of many factors, such as its fast growth and good mechanical properties. However, heat resistance is one of the significant drawbacks of bamboo, being a combustible material. With that in mind, this paper provides an insightful and complete investigation of the potential of tung oil and zirconia powder treatment on bamboo. Particularly, it shows the significant thermal stability improvement of the proposed surface treatment. The physicochemical and thermal properties were investigated using colour measurement, Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA). The colour measurement served as a good indicator of the extent of the effect of the heat through charring. The sample treated with 0.6 g/ml of zirconia and tung oil darkened the least from the highest heating indicative of the best resistance. FTIR confirmed the dimensional stability when comparing the absorbance peaks. It also revealed the deterioration of the untreated samples through C-O stretching. XRD was able to confirm the moderate effect of the heat on the treated samples through the absence of large crystallites and also as expected the phase stability of the Zirconia coating. The damage of the heat on the bamboo surfaces was apparent from the SEM micrographs showing surface undulation and crevices. The beneficial effect of the protective coating was also confirmed by examining the micro-level features. Finally, the thermal stability studied using TGA confirmed the efficiency of the tung oil with zirconia by abating the mass loss and rate of degradation.