title: Exploring the nature of cellulose microfibrils.
abstract: Ultrathin cellulose microfibril fractions were extracted from spruce wood powder using combined delignification, TEMPO-catalyzed oxidation, and sonication processes. Small-angle X-ray scattering of these microfibril fractions in a "dilute" aqueous suspension (concentration 0.077 wt %) revealed that their shape was in the form of nanostrip with 4 nm width and only about 0.5 nm thicknesses. These dimensions were further confirmed by TEM and AFM measurements. The 0.5 nm thickness implied that the nanostrip could contain only a single layer of cellulose chains. At a higher concentration (0.15 wt %), SAXS analysis indicated that these nanostrips aggregated into a layered structure. The X-ray diffraction of samples collected at different preparation stages suggested that microfibrils were delaminated along the (11̅0) planes from the Iβ cellulose crystals. The degree of oxidation and solid-state (13)C NMR characterizations indicated that, in addition to the surface molecules, some inner molecules of microfibrils were also oxidized, facilitating the delamination into cellulose nanostrips.
authors: Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States.
authors: Ying
authors: Y
authors: Su
authors: Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States.
authors: Christian
authors: C
authors: Burger
authors: Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States.
authors: Hongyang
authors: H
authors: Ma
authors: Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States.
authors: Benjamin
authors: B
authors: Chu
authors: Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States.
authors: Benjamin S
authors: BS
authors: Hsiao
mesh_terms: D002483:Cellulose, Oxidized / Q000737:chemistry*; D028222:Picea / Q000737:chemistry; D014934:Wood / Q000737:chemistry*
chemical_list: D002483:Cellulose, Oxidized