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Preparation and properties of cellulose nanocrystals: Rods, spheres, and network

2010; Elsevier BV; Volume: 82; Issue: 2 Linguagem: Inglês

10.1016/j.carbpol.2010.04.073

1879-1344

Ping Lü, You‐Lo Hsieh,

Polysaccharides and Plant Cell Walls

Cellulose nanocrystals with rod, sphere, and network morphologies were prepared by acid hydrolysis of cotton cellulose, followed by freeze-drying. Hydrolysis with sulfuric acid introduced sulfate groups to these nanocrystal surfaces permitting their dispersion in aqueous as well as organic media, including ethanol and N,N-dimethylformamide, in a matter of seconds. Freeze-drying, on the other hand, induced mesoporosity (91.99 ± 2.57 Å average pore width) and significantly improved specific surface (13.362 m2/g) that is about 9 times of the original cellulose (1.547 m2/g). Moreover, the nanocrystals exhibited improved thermal conductivity and considerably higher (nearly 30%) carbonaceous residue, possibly due to direct solid-to-gas decomposition. These results demonstrated that a combination of surface charge introduction and fixation of mesoporosity in cellulose nanocrystals is an efficient route to prepare large quantity of high quality cellulose nanocrystals with quick re-dispersion capability for practical applications.