Examination of the Effects of Chemical Treatments on the Mechanical, Chemical, and Physical Characteristics of <i>Hibiscus rosa-sinensis</i> Plant Fiber

Abstract

Natural fibres in recent years have been found to contribute a great share in making composites. Hibiscus rosa-sinensis plant fibres which are natural were used in this work and have not yet been tried to make the composites so far and easily available thus making this study very necessary it aims to perform various chemical treatments and to study the physical and chemical properties of them. The methodology adopted was that literature review, problem identification, extraction of fibres, treatment of fibres, chemical and mechanical testing of fibres, results and discussions and conclusion. Fibre chemical composition tests were also done to determine the constituents of the fibres. Two chemical treatment methods (alkalinization and benzoylation) were proposed in this work. Chemical treatments were found to improve surface roughness. Using Scanning Electron Microscopy (SEM), researchers examined the fibres' structural and morphological alterations and discovered that components like pectin were largely eliminated. The structural properties of fibres were known from X-ray diffractograms, and crystallinity percentages were found for the cellulosic fibres. Fourier Transform Infrared (FTIR) spectroscopy presented the spectra of the fibres which revealed the structure of organic compounds and the presence or the absence of functional groups. It showed the partial removal of hemicellulose and lignin. Axial tensile tests were performed for the fibres to know the maximum tensile force and percentage elongation. Chemical treatments partially removed impurities in the fibres and made morphological changes. The improvements in mean tensile values and percentage elongation were found in 5% alkali-treated and benzoylation-treated fibres, 56% and 63% higher than the untreated fibres respectively.