Acid and Alkali Treatment on Natural Fibers for Better Tensile Strength of Epoxy Composites
Nor Azwin AHAD, Rama Murthi A/L Sooria MOORTHI
Abstract. Natural fiber which known are from agricultural waste, fruit skin, stalks, and so on is considered recyclable also creating great demand as they come at a very low cost, are biodegradable, and have low density. However, natural fibers are hydrophilic in nature, so they tend to absorb water. Chemical treatments can usually overcome this problem. Usually, acid and alkali treatments are very popular among researchers. In this study, we focused on seeing the differences in the natural treatment of acidic and alkaline using citric acid (vinegar) and sodium bicarbonate (soda) of certain three types of selected fibers. The 24-hour treatments were studied on coconut coir, banana stem fiber, sugarcane bagasse, and corn stalk fiber. All the fibers acted as fillers in epoxy composites. The tensile strength has been investigated and compared between untreated and treated as well. All fibers were observed highest tensile strength after being treated with alkali compared to acid. Treatment with alkali is more suitable for natural fiber to clean the fiber surface, thus helping to get better fiber-matrix interaction. These are the reasons for the highest tensile strength.
Keywords
Natural Fiber, Acid Treatment, Alkali Treatment, Tensile Strength
Published online 7/15/2026, 5 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Nor Azwin AHAD, Rama Murthi A/L Sooria MOORTHI, Acid and Alkali Treatment on Natural Fibers for Better Tensile Strength of Epoxy Composites, Materials Research Proceedings, Vol. 68, pp 134-138, 2026
DOI: https://doi.org/10.21741/9781644904237-18
The article was published as article 18 of the book Green Materials, Processing & Characterization
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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