Microfibrillated Cellulose MFC

In contrast to CNW, microfibrillated cellulose (MFC) was able to improve the mechanical performance of GGM-based films [76]. Two levels of added MFC... 

There are four types of nanocellulose depending on their fabrication method bacterial cellulose, electrospun cellulose, microfibrillated cellulose (MFC) and whiskers of cellulose (nanorods). Bacterial cellulose is a nanomaterial derived from plant material by bacterial action in the presence of oxygen. Various strains of Acetobacter species [82,83] can be used to produce cellulose, although strains of pseudomonas, Achrobacter, Alcaligene, Aerobacter and Azotobacter [84] can also be used. The bacterial cellulose... 

Henriksson M, Henriksson G, Berglund LA, Lindstro m T et al (2007) An environmentally friendly method for enzyme assisted preparation of microfibrillated cellulose (MFC) nanofibres. Eur Polym J 43 3434—3441... 

This chapter discusses the potential and use of microfibrillated cellulose (MFC) and nanofibriUated cellulose (NFC) in papermaking. Cellulosic fibrils have many potential applications due to their structure. 

Different descriptors have been used in the literature to designate the crystalline rod-like nanoparticles. These particles are mainly referred to as whiskers, nanowhiskers, cellulose nanocrystals, NCC (nanocrystalline cellulose), monocrystals, microcrystals, or microcrystallites, despite their nanoscale dimensions. The terms microfibrils, microfibrillated cellulose (MFC), and nanofibrillated cellulose (NFC) are used to designate cellulosic nanoparticles obtained by a simple mechanical shearing disintegration process (Fig. 7.2) as described in the next section. 

The main aim of this contribution is to present various approaches to the preparation of nanocellulosic materials from plant sources. The focus is on the extraction and investigation of microfibrillated cellulose (MFC) in particular however, to put this topic in context, cellulose whiskers and bacterial cellulose are also discussed in particular sections of the text and applications of nanocellu-losics in the animal body for the development of medical devices such as artificial blood vessels, and the application of bacterial nanocellulose as animal woimd dressings and cosmetic tissues. Therefore, this chapter has brought together a variety of areas from chemistry, medicine, and biotechnology. 

Nakagaito AN, Fujimura A, Sakai T et al (2009) Production of microfibrillated cellulose (MFC)-reiirforced polylactic acid (PLA) nanocmnposites from sheets obtained by a paper-making-Uke process. Compos Sci Technol 69 1293—1297... 

Microfibrillated cellulose (MFC) originates from many various botanical sources, as well as algae and tunicate animals. It is also well-known that a certain type of bacterium... 

A new bio-based epoxy resin system has been prepared by curing epoxidized soybean oil with tannic acid under various conditions (Shibata et al., 2011) the authors have found that the most balanced properties were obtained when the system was cured at 210°C for 2 h with an epoxy/hydroxyl ratio of 1/1.4. Moreover, the authors prepared biocomposites starting from the bio-based epoxy resin using as reinforcements microfibrillated cellulose (MFC) with contents of these last from 5% to 11% in weight. 

Since the first announcement cellulose whiskers application as reinforcing phase by Favier et al. in 1995, new nanocomposite materials with original properties were obtained using cellulose nanowhiskers (C-NW) and microfibrillated cellulose (MFC) and led to the development of studies on chitin whiskers. 

Table 1 Comparison between eellulose nanocrystals (CNC) and microfibrillated cellulose (MFC)...

There are basically two families of nanosized cellulosic particles. The first one consists of cellulose nanocrystals and the second one is microfibrillated cellulose (MFC) [17]. However, different terminologies are used to describe these cellulose nanoparticles, leading to some misunderstanding and ambiguities. Currently, the isolation, characterization, and search for applications of novel forms of cellulose, variously termed crystallites, nanocrystals, whiskers, nanofibrils, and nanofibers, is generating... 

Over time, a number of possibilities have been explored to produce cellulose-based nanometric fillers. In particular, microfibrillated cellulose (MFC) (Section 6.2.1) is formed by fibrous cellulose structures with the length of several tens of microns and generally a few tens of nanometers thick, as it consists of aggregates of microfibrils, natmally occurring as an effect of the hierarchical structure of cellulose in plants [3]. In other words, MFC is formed by long, flexible and entangled cellulose nanofibers, where both amorphous and crystalline phases are present [4]. 

Nanocellulose can broadly be defined as a set of particles having at least one dimension in nanoscale obtained by different mechanical/chemical, or only chemical, or acid-hydrolysis methods. According to a survey of the literature, there is no standardized nomenclature for cellulose-based nanoparticles, while various terms have been used to describe a particular set of cellulose nanoparticles. Because of inconsistency in use of these terms, there are some particle types depending on source materials of cellulose and method of extraction. However, depending on their aspect ratio, nanocelluloses have already been characterized with different terms like microfibrillated cellulose (MFC-diameter 10-100 nm) [34], nanofibrillated cellulose (NFC-diameter 4-20 nm) [35], CNCs (CNCs-diameter 3-5 nm) [34, 36], tunicate CNCs (t-CNCs-diameter 20 nm) [34, 37], algae cellulose particles (AC-diameter 20 nm) [38,39], bacterial cellulose particles (BC-diameter 6-50 nm) [40, 41]. It can commonly be called "nanocellulose,"... 

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