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Interest in nanofibrillated cellulose has been increasing exponentially because of its relatively ease of preparation in high yield, high specific surface area, high strength and stiffness, low weight and biodegradability etc. This biobased nanomaterial has been used mainly in nanocomposites due to its outstanding reinforcing potential. Solvent casting, melt mixing, in situ polymerization and electrospinning are important techniques for the fabrication of nanofibrillated cellulose-based nanocomposites. Due to hydrophilic character along with inherent tendency to form strong network held through hydrogen-bonding, nanofibrillated cellulose cannot uniformly be dispersed in most non-polar polymer matrices. Therefore, surface modification based on polymer grafting, coupling agents, acetylation and cationic modification was used in order to improve compatibility and homogeneous dispersion within polymer matrices. Nanofibrillated cellulose opens the way towards intense and promising research with expanding area of potential applications, including nanocomposite materials, paper and paperboard additive, biomedical applications and as adsorbent.

The adsorption of several prehydrolyzed alkoxysilanes onto the surface of cellulosic fibers in ethanol/ water mixtures has been studied quantitatively. The corresponding isotherms show the formation of a monolayer followed by further adsorption. The nature of the fourth substituent on the silane plays a specific role on the features of this association. Whereas at room temperature only dispersive and polar attractive interactions occur, heating above 100 °C produces condensation reactions resulting in covalent bonding between the substrate and the silane forming the monolayer. As a result of this investigation, the possibility of calling upon this surface modification in order to compatibilize cellulosic fibers with polyolefinic matrixes for the elaboration of composite materials seems to be a promising strategy.

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