title: Cellulose nanofibrils prepared from softwood cellulose by TEMPO/NaClO/NaClO₂ systems in water at pH 4.8 or 6.8.
abstract: Catalytic oxidation of softwood cellulose using NaClO and either 2,2,6,6-tetramethylpiperidine-1-oxyl (4-H-TEMPO) or 4-acetamido-TEMPO (4-AcNH-TEMPO) was applied with NaClO(2) used as a primary oxidant in an aqueous buffer at pH 4.8 or 6.8. When the 4-AcNH-TEMPO-mediated oxidation was applied to softwood cellulose in water at pH 4.8 and 40 °C, the carboxylate content rose to ∼1.3 mmol/g after reaction for 48 h and the DP(v) value was more than 1100. This 4-AcNH-TEMPO-oxidized softwood cellulose was mostly converted to individual nanofibrils by mechanical disintegration in water, with uniform widths of 3-4 nm and lengths greater than 1 μm.
authors.affiliation: Department of Biomaterials Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan.
authors.forename: Reina
authors.initials: R
authors.lastname: Tanaka
authors.forename: Tsuguyuki
authors.initials: T
authors.lastname: Saito
authors.forename: Akira
authors.initials: A
authors.lastname: Isogai
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D002384:Catalysis; D002482:Cellulose / Q000138:chemical synthesis* / Q000648:ultrastructure; D002483:Cellulose, Oxidized / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry*; D003497:Cyclic N-Oxides / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D012973:Sodium Hypochlorite / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D000447:Aldehydes; D002483:Cellulose, Oxidized; D002712:Chlorides; D003497:Cyclic N-Oxides; D014867:Water; D002482:Cellulose; D012973:Sodium Hypochlorite; C003959:TEMPO; C001599:chlorite