Facile synthesis of sulfonated cellulose derived from sugarcane bagasse via solution plasma process toward bio-filler separator membrane for lithium-ion battery

Sulfonated cellulose (SC) is a water-soluble derivative cellulose with sulfonic acid groups (SO₃^2-) bound to carbon atom in the glucopyranose monomers of cellulose backbone. First, cellulose was extracted from sugarcane bagasse, and then hydrolyzed to small particles in term of microcrystalline cellulose (MCC). After that, the MCC was modified by the oxidation reaction with NaIO₄ to provide cleavage of the C-C bonds to form 2,3-dialdehyde cellulose (DAC). Subsequently, these activated aldehyde groups were significantly substituted with sulfonic acid groups in the sulfonation reaction via the solution plasma (SP) reaction with 0.05 mmol of K₂S₂O₅. With the increasing of SP processing time could increase the content of the sulfonic acid groups in the SC (154 - 720 µmol/g). Due to the increase of sulfonic acid group content, the plasma-treated SC were more dissolved in water and showed the transmittance of higher than 90% in the 400 - 800 nm range, leading to water solubility improvement up to 86.69%. The SP provided the advanced benefits to the synthesis of SC by using a low concentration of K₂S₂O₅, which were the increased sulfonic acid group contents. The obtained plasma-treated SC were further evaluated for use as a bio-filler in bio-membranes for lithium-ion applications.