Nanocelluloses occur under various crystalline forms that are being selectively used for a wide variety of high performance materials. In the present work, cellulose fibers (CF-I) were mercerized by alkaline treatment (CF-II) without molar mass variation (560 000 g/mol) and both were acid hydrolyzed, forming cellulose nanocrystals in native (CNC-I) and mercerized (CNC-II) forms. This work establishes detailed characterization of these two nanoparticles morphology (light and neutron scattering, TEM, AFM), surface chemistry (zetametry and surface charge), crystallinity (XRD, 13 C NMR), and average molar mass coupled to chromatographic technics (SEC-MALLS-RI, A4F-MALLS-RI), evidencing variations in packing of the crystalline domains. The crystal size of CNC-II is reduced by half compared to CNC-I, with molar masses of individual chains of 41 000 g/mol and 22 000 g/mol for CNC-I and CNC-II respectively, whereas the same charged surface chemistry is measured. This fundamental analysis may give insight to new applicative development.

Ultrasonic irradiation of cellulose at a high frequency induces its selective depolymerization to glucose at room temperature and atmospheric pressure within only a few minutes.