title: Extraction of cellulose nanofibrils from dry softwood pulp using high shear homogenization.
abstract: The objective of this study was to extract cellulose nanofibrils (CNFs) from dry softwood pulp through a simple and environmentally friendly physical method of refining pretreatment coupled with high shear homogenization. An optical microscopy (OM) clearly showed the morphological development from the cellulose fibers to CNFs under repeated shear forces. The morphology, structure and properties of the obtained CNFs were comprehensively investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformed infrared (FTIR) spectra, X-ray diffraction (XRD) and thermogravimetric (TG) analysis. The results indicated that the CNFs had diameters mainly ranged from 16 to 28nm. Compared with the pulp fibers, the CNFs exhibited a slightly higher crystallinity and a lower thermal stability. Moreover, a novel nanopaper with high optical transparency was prepared from the obtained CNFs, and a possible mechanism for the high optical transparency was discussed.
authors.affiliation: State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute at Sichuan University, Chengdu 610065, China.
authors.forename: Jiangqi
authors.initials: J
authors.lastname: Zhao
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Zhang
authors.forename: Xinxing
authors.initials: X
authors.lastname: Zhang
authors.forename: Canhui
authors.initials: C
authors.lastname: Lu
authors.forename: Yulin
authors.initials: Y
authors.lastname: Deng
mesh_terms: D001671:Biochemistry / Q000379:methods*; D002482:Cellulose / Q000302:isolation & purification* / Q000648:ultrastructure; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D010209:Paper; D033081:Shear Strength; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry; D014934:Wood / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D002482:Cellulose
keywords: Cellulose nanofibrils; Crystallinity; High shear homogenization; Refining; Thermal properties