Evaluation and comparison of the behavioral properties of raw, alkali-treated, and triethoxy silane–treated cellulosic fibers derived from Rottboellia cochinchinensis plant as a substantial material for polymer composites

Abstract

This investigation involved isolating a unique cellulosic fiber from the Raoul grass plant (Rotboellia cochinchinensis) and compared the behavioral effects of raw fiber with various chemical treatments, specifically 5 % NaOH and a 70: 30 mixture of (3-aminopropyl) triethoxy silane, on Raoul grass fiber. The treatments were conducted for 45 min, after which the fiber properties were evaluated. The cellulose percentages of the alkalized and silane-treated fibers increased to 72.29 % and 75.07 %, respectively, whereas the raw fiber contained 65.23 %. The X-ray diffraction study revealed a significant increase in the crystallinity index of the alkalized and silane-treated fibers, with an increase of 41.8 % and 43.89 %, compared to the 33.6 % found in the raw fiber. Thermogravimetric analysis established that both the alkalized and silane-treated fibers exhibited a maximum degradation peak at 366.27 °C. The kinetic activation energies for the alkalized and silane-treated fibers were 60.63 and 64.52 kJ/mol, respectively. The energy-dispersive spectroscopy spectrum of the alkalized and silane-treated Raoul grass fiber showed no impurity elements, indicating the successful elimination of impurities from the fiber's surface. These findings conclude that silane treatment is the most suitable method, and Raoul grass is a promising material for reinforcement in fiber-reinforced plastics.