Alkali/Ultrasound Treatment as Alternative to Modify Structural and Thermal Properties of Agave tequilana Fibers

Abstract

This study aims to investigate the effect of alkali and ultrasound treatment on the structural (XRD/FTIR), morphological (SEM), and thermal (TGA) properties of Agave tequilana fibers, which could be useful as reinforcement for biopolymer composites. A decrease in 35% lignin content at 3% NaOH concentration was observed, since the alkali/ultrasound treatment breaks the hydrogen bonds of the structural components in the fiber and contributes to the cellulose fraction’s concentration, increasing the crystallinity percentage without changing its fiber crystal pattern (cellulose Iα). Morphological changes in the fiber, such as high roughness and porosity, were also observed. It can be concluded that fiber treatment with 3% NaOH, immersion time of 12 h and sonication for 60 min was the most effective method to enhance the fiber properties. Furthermore, the modified fibers show high thermal resistance suggesting their application in automotive components manufacturing processes that involve high temperature.

Keywords

• agave tequilana fibers
• alkali treatment
• ultrasound
• lignin
• thermal properties
• cellulose