Micro/nanofibrillated cellulose

Cellulose nanofibers, also called micro/nanofibrillated cellulose (MFC/NFC), are obtained by mechanical disintegration after the raw cellulosic materials were chemically or enzymatically pretreated to get pure cellulose. Thus, the MFC has a high aspect ratio with a length over 1000 nm including crystalline and amorphous cellulose (Siro and Plackett, 2010). Microfibrillar cellulose (MFC) shows more commercial production availability than hydrolyzed CNC (Brinchi et al., 2013). 

Potential Use of Micro- and Nanofibrillated Cellulose Composites Exemplified by Paper... 

Keywords Biopolymers Calcium carbonate Cellulosic fibrils Composites Coprecipitation Micro- and Nanofibrillated cellulose Morphology Pigments Properties... 

In some cases the isolation of cellulose micro/nanofibrils involves enzymatic pretreatment followed by mechanical treatments [22,23]. The morphology and aspect ratio of the extracted nanofibers may vary depending upon the raw materials and extraction techniques [24]. Examples of various cellulose nanofiber extraction methods, including microfibrillar cellulose (MFC) are shown in Table 5.1. 

Cai ILL, Sharma S, Liu WY, Mu W, Liu W, Zhang XD, Deng YL (2014) Aerogel micro-spheres from natural cellulose nanofibrils and their application as cell culture scaffold. Biomacromolecules 15 2540-2547... 

Figure 17-5. Ultrafine net of microbial cellulose (a) has a very smooth network of micro- and nanofibrils and (b) the cross-section of MC membrane with multilayer architecture...

The dominating S2-layer contains the cellulose micro fibrils orientated under an acute angle toward the fiber axis. Such orientation of the microfibrils imparts to natural cellulose fibers increased mechanical properties. The microfibrils of the cell wall consist of elementary nanofibrils, and each such fibril is built of ordered nanocrystallites and low ordered non-crystalline (amorphous] domains statistically alternated along the fibril. The early investigations supposed the presence in various cellulose samples of elementary nanofibrils having a constant lateral size of 3.5 nm (Manley, 1964 Muhlenthaler, 1969]. However, recent... 

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