Research Publications (Engineering and Built Environment)
Permanent URI for this collectionhttp://ir-dev.dut.ac.za/handle/10321/215
Browse
Search Results
Item A review of the implications of polyethylene plastics when utilized as chemical storage tanks(Journal of Aeronautical Materials, 2024-05-01) Khanyi, Nhlanhla F.; Tabakov, Pavel Y.; Inambao, Freddie L.Many studies have been conducted to investigate the impact or influence of polyethylene (PE) plastic when used as chemical liquid storage. Herein, this literature addresses the factors that contribute to the degradation of chemical storage tanks as a result of PE plastics and how they can be mitigated. This is achieved by reviewing and discussing the significant properties of High-density polyethylene (HDPE), which have been reported to degrade the chemicals stored in these storage tanks. The method of cross-linking the PE was reviewed with its preceding processes that involve chemical and physical processes. The influence of each agent on the resulting properties is discussed in detail including the effect of cross-linking degree. These methods were found to be significant in improving some of the properties of HDPE to better store chemical substances. Nonetheless, it was established that the main concern of PE plastics is environmental stress cracking (ESC), which causes unexpected cracks within the HDPE storage tanks, thus degrading the substance contained. The currently used method or test (bentstrip) to determine the resistance of PE to ESC and techniques used to monitor it were reviewed and discussed in detail. Consequently, the literature suggests that the relationship between the density of PE and its ESC susceptibility has been found to be significant. However, research has shown that relying solely on density as a predictor of ESC in PE when exposed to chemical substances is insufficient, and further studies should be conducted to investigate other parameters that contribute to ESC in PE. In addition, the review suggests that future research should focus on studying ESC resistance of newly developed Nano-filled PE composites or biodegradable PE variants, as these are future materials for storing chemical substances conveniently.Item The impact of mild steel, stainless steel, and high-density polyethylene on the foaming ability and foam stability of aqueous film forming foam in aviation(Journal of Aeronautical Materials, 2024-05-01) Khanyi, Nhlanhla F.; Tabakov, Pavel Yaroslavovich; Inambao, Freddie L.Aqueous Film Forming Foam (AFFF) has become a critical component within the aviation industry. However, relatively few reports address the causes of the poor performance of AFFF during fire conditions due to the rarity of air crashes. Herein, the impact of mild steel, stainless steel, and high-density polyethylene on the foaming ability and foam stability of AFFF was experimentally investigated. The functional groups, particle shape, size, size distribution, and elementary analysis were conducted using the Fourier transform infrared spectroscopy, transmission electron microscopy, dynamic light scattering, and inductively coupled plasma atomic emission spectroscopy. The results showed that all three materials affect the foam ability and foam stability of AFFF in some manner, with mild steel having the most severe impact. The recommendations to use cross-linked polyethylene and fiberglass materials for better storing AFFF concentrate were thoroughly discussed.