Nanofibrillar cellulose

Lou Y-R, Kanninen L, Kuisma T et al (2014) The use of nanofibrillar cellulose hydrogel as a flexible three-dimensional model to culture human pluripotent stem cells. Stem Cells Dev... 

Bhattacharya M, Malinen MM, Lauren P et al (2012) Nanofibrillar cellulose hydrogel promotes three-dimensional liver cell culture. J Cmitrol Release 164 291—298... 

Hoepfher S, Ratke L, Milow B (2008) Synthesis and characterisation of nanofibrillar cellulose aerogels. Cellulose 15 121-129... 

Jin H, Nishiyama Y, Wada M, Kuga S (2004) Nanofibrillar cellulose aerogels. Colloid Surf A Physicochem Eng Asp 240 63-67... 

There are basically two families of nanosized cellulosic particles (1) Nanofibrillar cellulose, which includes mechanically isolated microfibrils, chemically isolated microfibrils (TEMPO-oxidation), bacterial cellulose and can be considered spaghetti-like, and (2) Cellulose nanocrystals - rods of highly crystalline cellulose which are isolated by acid hydrolysis. Cellulose nanocrystals are represented in literature by synonyms like cellulose whiskers, cellulose nanowhiskers, cellulose microfibrils, micro-crystalline cellulose and nanocrystalline cellulose because they are not yet commercially available. These are needle-shaped (100 run to 200 run X 10 nm), highly crystalline, strong (E - 150 GPa) and form liquid crystal suspensions. 

Nanofibrillar cellulose which includes mechanically isolated microfibrils, chemically isolated microfibrils (TEMPO-oxidation), bacterial cellulose and can be considered as spaghetti-like ... 

Two different strength properties of the handsheets are compared in Fig. 5.18. According to the figure, an increased amount of fines significantly enhances the tensile strength of the new composite paper. Nanofibrillar cellulosic fines contribute... 

The formation of the new composite and reference samples is illustrated in Fig. 5.21. It can be concluded that the formation improves with increasing amounts of nanofibrillar cellulose and PCC in the paper. Addition of 10% regenerated cellulose long fibres impairs the formation, while addition of softwood fibres results in a formation comparable to that of the reference handsheets. The handsheets were prepared from a suspension with a consistency of 4.3%. This combination of raw materials might also be suitable for higher consistencies, so the formation of handsheets at higher consistencies needs to be evaluated in detail. 

At nanoscale thickness, fibrils are named as nanofibrillar cellulose (NFC) or nanocellulose [26-28]. Highly crystalline cellulose nanowhiskers, also called cellulose micelles, cellulose nanorods, cellulose nanocrystals, or nanocrystalline cellulose are produced under strong acid hydrolysis (e.g., mineral acids such as hydrochloric acid or sulphuric acid) combined with mechanical shearing [22, 29]. 

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