Efficient depolymerization of cotton cellulose achieved by dielectric barrier discharge: Structural evolution mechanisms

High-polymer biomass is reactively inert due to its large molecular weight and stable structure, and the depolymerization is an effective strategy to enhance its utilization. Herein, a typical dielectric barrier discharge (DBD) system was established to realize efficient depolymerization of cotton cellulose, where the degree of polymerization declined from 2329 to 430, decreased by 81.5%. H 2 O 2 , O 3 , •OH, O 2 • − and 1 O 2 dominated the depolymerization process by attacking the β -(1,4) glycosidic bonds and hydrogen bonds in cellulose molecules. In addition, the treated cotton cellulose displayed smaller blocks, rougher surface and poor thermal stability, and the crystallinity of cellulose decreased by 15.4% after DBD pretreatment. Interestingly, there were no obvious chemical changes in the main structure of cellulose, only with slight release of substances such as monosaccharides and alcohols. Therefore, these indicated that DBD process achieved the reduction of polymerization and crystallinity while ensuring that the original cellulose structure was not damaged, and was an efficient and alternative pretreatment method for high-polymer biomass.