Engineering

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Browsing Engineering by Author "Baloyi, R.B."

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    Analysis of the properties of a glass/sisal/polyester composite
    (Springer Nature, 2021-01-11) Baloyi, R.B.; Ncube, S.; Moyo, M.; Nkiwane, L.; Dzingai, P.
    Composites are gradually becoming an integral material for structural and manufacturing processes. Sisal fibre has the potential to be one of the leading reinforcement natural fibres, not only in Zimbabwe, but the world over for use in glass composites. This is mainly due to it being inexpensive, exhibiting a low density, high specifc strength, a high stiffness to weight ratio, non-toxicity, its abundance in Zimbabwe and its renewability. With an aim of coming up with a composite for partition board applications in the construction industry, five samples of sisal-glass composite were prepared with varying sisal fibre content and diferent layering techniques. Sisal fbres were pre-treated with 20% NaOH to enhance their crosslinking with the resin and reduce the chemical impurities such as lignin and waxes. Mechanical (fexural test, hardness, and tensile strength) and physical tests (density and water absorption) were conducted to analyse the properties of the composite. The results showed that treated sisal fibres had a higher breaking tenacity of 33.11 g/tex which is higher than untreated fibres with a breaking tenacity of 25.72 g/tex. The best properties were obtained in the sample with 4 layers of glass and 9 layers of sisal fibres using 200 ml of resin. The composite had a tensile strength of 57.60 MPa, fexural strength of 36 N/mm2, moisture absorption of 10% and a burning rate of 9.82 mm/ min. These results were then compared with those of the current partition boards in the market. It was noted that the composite was suitable for use in partition boards. Again, regarding cost, these composites are cheaper to produce at a rate of $11.33/m2 compared to the timber costing at $16/m2.
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    Microplastics Originating from Paints and Synthetic Textile Materials
    (Springer Nature Singapore, 2024-04) Moyo, M.; Baloyi, R.B.; Sithole, B.B.; Falayi, T.
    There is continued growth in paints and synthetic textile materials production and consumption due to expanded use of paints in different applications, population growth and fast fashion trends. Paints and synthetic textile materials are some of the major sources of microplastics. The major sources of microplastics originating from paints are marine paints, road markings, architectural paints, and spray painting. Major contributing factors in the release of microplastics from paints to the environment are paint production processes, weathering and abrasion, paint spilling, residual paints on paint application tools and storage containers, paint end of life (EoL) disposal, and paint applicator’s expertise. In the context of synthetic textile materials, major emissions of the microplastics occur during the production processes of the synthetic textile materials, during use and laundering, washing conditions and drying. Studying the role and influence of paints and synthetic textile materials in the generation of microplastics is critical. It helps in coming up with mitigatory measures to reduce the generation of microplastics from paints and synthetic textile materials and hence promotion of sustainability. Devising a holistic approach to research and development of green chemistry and green manufacturing processes in the production of paints and synthetic textile materials is one of the mitigatory measures. Also, developing policies and legislation on wastewater treatment systems for all responsible stakeholders and introducing legislation on do-it-yourself (DIY) painting activities could help in reducing the generation of microplastics from paints and synthetic textile materials.