Extraction of Cellulose Nanofillers

Many studies have been done on isolation and characterization of cellulose nanofibers from various sources. Cellulose nanofibers can be extracted from the cell walls by simple mechanical shearing or by a combination of both chemical and mechanical routes [10]. 

Alemdar and Sain [19] have extracted cellulose nanofibers from wheat straw by a chemical treatment followed by a mechanical treatment (cryocrushing, disintegration, and defibrillation steps) to individuahze the nanofibers from the cell walls. 

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. 

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 

Method Raw materials Procedure Extracted nanfiber dimensions 

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Nanocellulose Polymer Nanocomposites 5.2.5 Extraction of Cellulose Nanofillers... 

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