The effects of the multi-walled carbon nanotube (MWNT)/cellulose nanocompositeson their physical properties

The multi-walled carbon nanotube (MWNT)/ cellulose nanocomposites were prepared using monohydrated N-methylmorpholine-N-oxide (NMMO) as a solvent for dispersing the acid-treated MWNT (A-MWNT) as well as dissolving cellulose. The A-MWNTs were well dispersed in both monohydrated NMMO and the nanocomposite films. The nanocomposite films were prepared by a film-casting method onto a glass plate. The casted films were immersed into distilled water to coagulate, and dried for a day in the sample holder. Tensile strain at break, Young's modulus, and toughness of the nanocomposite films increased ∼ 5, ∼ 2 and ∼12 times, respectively, as compared to those of the pure cellulose film by adding 0.8 wt% A-MWNT. Thermal degradation temperature and electrical conductivity of the nanocomposite film increased from 329 to 339 °C and from 2.09 × 10^-5 to 3.68 × 10^-3 S/cm, respectively by adding 1 wt% A-MWNT. The transmittances were 86, 69 and 55 % at 550 nm for 0.4, 0.8 and 1 wt% nanocomposite films, respectively. Thus the A-MWNT/cellulose nanocomposites (which were prepared by a so-called "Lyocell" process) were a promising material in all properties studied in this paper and can be used for many applications, such as toughened cellulose fibers, transparent electrodes, etc.