Study of the Physical Properties of Braided Sisal Fibers Treated with Sodium Hydroxide Solution and Treated with Softening Finishing Agent

Abstract

This study aimed to investigate the effects of treating braided sisal fibers with sodium hydroxide solution at varying concentrations (5, 10, 15, 20, and 25 g/L) in combination with softening agents (5 and 20 g/L), incorporating a fixed amount of silicone (5 g/L). The treated fibers were tested for their physical properties, including size, tensile strength, elongation percentage, color values, and softness. The fibers underwent an alkaline boiling process followed by immersion in the softening agent before being analyzed using standard instruments and evaluated for softness by a group of 25 participants from the Hub Kha Phong community in Phetchaburi Province. The experimental results indicated that treatment with sodium hydroxide alone significantly reduced fiber size at a concentration of 15 g/L, which then began to increase again when the concentration exceeded 20 g/L. This trend aligned with the initial decline in tensile strength and elongation, which slightly improved as the alkaline concentration increased. Meanwhile, the L* color value decreased and then rose again at the highest concentration level, reflecting structural changes within the fibers. When combined with the softening treatment, it was found that fibers treated with a softening agent at 20 g/L along with sodium hydroxide at 20 g/L received the highest softness rating at 72.06% and achieved the highest K/S color intensity value at an alkaline concentration of 15 g/L. The use of a softening agent effectively reduced fiber coarseness, resulting in a softer surface texture, slightly deeper color, and acceptable elasticity, despite a slight reduction in mechanical strength. This experiment demonstrates that sisal fibers can be suitably modified for use in textile products that require a soft hand feel and desirable color properties, without relying on synthetic materials. Furthermore, it adds economic value to agricultural waste and promotes the sustainable use of environmentally friendly materials within the fashion industry.