Functionalized nanocellulose

Due to the amorphous structure, ANP acquires such specific features as increased content of functional groups, high accessibility, and sorption ability (loelovich, 2013a, 2014a). Freeze-dried amorphous nanocellulose has an enhanced wetting enthalpy (—125 to — 130J/g), absorbs up to 35—40% water vapor, and completely decomposes under action of cellulolytic enzymes. Moreover, the chemical modification of ANP is carried out faster and deeper than other kinds of nanocellulose. 

Klemm, D., Schumann, D., Kramer, F., HeBler, N., Koth, D., Sultanova, B., 2009. Nanocellulose materials—different cellulose, different functionality. Macromol. Symp. 280 (1), 60-71. 

Changing the surface functionality of the cellulose nanoparticle can also affect the permeability of nanocellulose films. Films constituted of negatively charged cellulose nanowhiskers could effectively reduce permeation of negatively charged ions, while leaving neutral ions virtually unaffected. Positively charged ions were found to accumulate in the membrane [70]. 

Recent advances in the field of biomaterials and their medical applications indicate the significance and potential of various nanoceUulose in the development of novel classes of medical devices and applications in healthcare and veterinary medicine. The physical and mechanical properties of nanocellulose are attributes that enable nanocellulose membranes to function as effective temporary wound dressings. On the other hand, because implantable biomaterials (i.e., scaffolds) are also needed, a new approach has been undertaken to apply cellulose as a material entirely integrated into the body, either as a bone or skin graft. 

Based on the above concept, we developed a new supramolecular associated form of glucan chains, nematic ordered cellulose (NOC), which is highly ordered, but not crystalline (Kondo et al. 2001). NOC has unique characteristics in particular, its surface properties provide with a function of tracks or scaffolds for regulated movements due to the inverse force in production of nanocellulose fibers of Acetobacter xylinum (Kondo et al. 2002). When the... 

Klemm D, Schumann D, Kramer F, Hesler N, Koth D, Sultanova B (2009) Nanocellulose materials—different cellulose, different functionality. Macromol Symp 280 60-71 Lande S, Hoibo OA, Larnoy E (2010) Variation in treatability of Scots pine (Pinussylvestris) by the chemical modification agent furfuryl alcohol dissolved in water. Wood Sci Technol 44 105-118... 

There has been Intense ongoing research to avoid the complex surface functionalization techniques. One of the new techniques is to combine the synthesis and functionalization of nanocellulose in a single step (see reference [47]). 

A similar approach was also considered by Valentini et at [171] that successfully prepared homogeneous and conductive cellulose nanocrystals/graphene oxide (GO) composite films. The authors proved how the application of an electric current through the composite leads to the formation of a conductive NCC/GO film highlighting many exciting functional properties of graphene-based nanocellulose composites. 

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