High-Quality Natural Fibers from Cotton Stalk Bark via Limited Alkali Penetration and Simultaneous Accelerated Temperature Rise

Abstract

High-quality cotton stalk fibers that are both fine and have a high breakage strength are extracted via limited alkali penetration in the glycerol solvent and simultaneous accelerated temperature rise by means of microwave-assisted heating. Alkali is widely used in the extraction of cotton stalk fibers. However, alkali molecules in the aqueous phase penetrate easily into the fiber bundles, resulting in a simultaneous degumming between the inner and outer layers of the fiber bundles. In previous reports, the fibers treated in the aqueous phase present a coarse fineness (51.0 dtex) under mild conditions or have a poor breakage strength (2.0 cN/dtex) at elevated temperatures. In this study, glycerol is chosen as a solvent to reduce the penetration of alkali. Simultaneously, the microwave-assisted heating form is adopted to increase the temperature to 170 °C within 22 s. The inhibited alkali penetration and accelerated temperature rise limited the delignification to the outer layer, resulting in fibers with both appropriate fineness (23.8 dtex) and high breakage strength (4.4 cN/dtex). Moreover, the fibers also exhibit a clean surface and large contact angle. In this paper, we detail a new strategy to extract high-quality lignocellulosic fibers that will be suitable for potential reinforcing applications.

Ligninolytic characteristics of Pleurotus ostreatus cultivated in cotton stalk media

“…The research on cotton straw delignification is intended for application in industrial production and is mainly related to physical and chemical methods ( Karthyani et al, 2020 ; Cheng et al, 2022 ; Dong Z. et al, 2022 ). With the intensive research on white rot fungi, some strains with high production of lignin degrading enzymes were also applied for delignification production ( Meehnian et al, 2016 ; Wittner et al, 2021 ; Sabogal-Otalora et al, 2022 ).…”

“…The degradation of cotton stalk lignin by a CDs/CuO synergistic emulsion system was investigated by Dong Z. et al, (2022) , and the results showed that H-type monomers were the main products of lignin degradation in this system. However, during lignin degradation by using P. ostreatus , S-type monomers and G-type monomers were the main degradation products, and the S lignin unit was more easily degraded than the G lignin unit, and the G/S ratio exhibited an upward trend.…”

Proximate Chemical Analysis and Effect of Age and Height of Oxytenanthera abyssinica on Fiber Morphology and Chemical Compositions for Pulp and Paper Production Potential

“…Safranine is a common azo dye used for plant microscopy, particularly as a stain for tissues that have been lignified, including the xylem. Safranine fluorescently marks the wood cell wall, causing green/yellow fluorescence in the secondary cell wall and red/orange fluorescence in the area of the middle lamella (ML) [48,49].…”