| 초록 |
The process of TEMPO-mediated oxidation was applied that the preparation of carboxyl-functionalized cellulose nanofibrils. TEMPO-oxidized cellulose nanofibrils (TOCNs) measuring 4 to 10 nm in width and several micron in length (aspect ratio is over 100) have been prepared from commercial wood pulp. It was found that the without additives or any surface modification, resulted in homogeneous dispersibility in organic solvent such as DMF or DMAc. The hyperfine and homogeneous cellulose nanofibers in polyurethane matrics leads to superior reinforcing effect of nanocomposites compared to the use of conventional nanocelluloses such as CNC, MFC and bacteria cellulose. The tensile strength and strain-to-failure of the nanocomposites were remarkably improved with low cellulose nanofibrils addition levels and, additionally enhancing the thermal stability of rubbery material, i.e., original polyurethane matrix. |
