title: Cellulose nanofibrils improve the properties of all-cellulose composites by the nano-reinforcement mechanism and nanofibril-induced crystallization.
abstract: All-cellulose nanocomposite films containing crystalline TEMPO-oxidized cellulose nanofibrils (TOCNs) of 0-1 wt% were fabricated by mixing aqueous TOCN dispersions with alkali/urea/cellulose (AUC) solutions at room temperature. The mixtures were cast on glass plates, soaked in an acid solution, and the regenerated gel-like films were washed with water and then dried. The TOCN did not form agglomerates in the composites, and had the structure of TOCN-COOH, forming hydrogen bonds with the hydroxyl groups of the regenerated cellulose molecules. X-ray diffraction analysis revealed that the matrix cellulose molecules increased the cellulose II crystal size upon incorporation of TOCN. As a result, the TOCN/AUC composite films had high Young's modulus, tensile strength, thermal stability and oxygen-barrier properties. The TOCN/AUC composite films are promising all-cellulose nanocomposites for versatile applications as new bio-based materials.
authors.affiliation: Department of Biomaterials Science, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. aisogai@mail.ecc.u-tokyo.ac.jp.
authors.forename: Quanling
authors.initials: Q
authors.lastname: Yang
authors.forename: Tsuguyuki
authors.initials: T
authors.lastname: Saito
authors.forename: Lars A
authors.initials: LA
authors.lastname: Berglund
authors.forename: Akira
authors.initials: A
authors.lastname: Isogai