Cellulose-based composites

Dufresne A (2008) Cellulose-based composites and nanocomposites. In Belgacem MN, Gandini A (eds) Monomers, polymers and composites from renewable resources. Elsevier, Amsterdam... 

Influence of Polysaccharide Composition on the Structure and Properties of Cellulose-based Composites... 

In summary, based on studies of Acetobacter cellulose-based composites, the following effects of two polymer types have been found ... 

Synthesis and Characterization of Bacterial Cellulose-Based Composites and Their Applications... 

The aim of this paper was to report the results of our studies on the modification of cellulose and cellulose-based composites with urease inhibitors. The obtained data support our suggestion that the new technology is a simple and effective way of controlling ammonia odor caused by the decomposition of urine. Another seemingly important benefit of this approach is the ability of the modified systems to maintain the pH at a level benign to skin. In addition to that, the evidence bas on our lab data suggests that the applied treatment not only retards the emission of ammonia but can also help reduce other odors typically related to menses and sweat. 

A. Dufresne, A. Cellulose-based composites and nanocomposites, in A. Gandini, and M.N. Belgacem, eds.. Monomers, Polymers and Composites from Renewable Resources, 1st ed., Elsevier Oxford, UK, pp. 401-418, 2008. 

A different approach aimed at elaborating composite materials for microwave technology called upon the coating of cellulose fibres with a metal like copper [12]. Finally, magnetically active cellulose-based composites have also been described [13] by the incorporation of barium ferrite into a regenerated fibre structure. 

Compos. Interface, 12, 2005. A special issue devoted to cellulose-based composites. 

Keywords Cellulose-based composites Composite properties cellulose Nanofibrillated cellulose Production methods... 

The expectation placed on cellulose-based composites lies in the Young s modulus of the cellulose crystallite. This was first experimentally studied in 1962 from the crystal deformation of cellulose I using highly oriented fibers of bleached... 

Fig. 15.1 Schematics of competitive chemical bonds promoted by diisocyanates in all-cellulosic based composites. Chemical coupling between fibers and matrix and cross-linking between anhydroglucose units of the matrix are shown. R refers to an aliphatic or aromatic group. The matrix is hydroxypropylcellulose (HPC)...

The designation all-cellulosic based composites is used throughout this chapter that focuses on the production and characterization of these materials. 

The all-cellulosic based composites were prepared in the form of dense films (thickness 20-60 pm). Clear composite films were obtained either from isotropic or liquid crystalline solutions of HPC (chiral nematic) by a casting method. 

Fig. 15.2 POM photographs of isotropic (b) and anisotropic (d) all-cellulosic based composites with 4% w/w HPC of Avicel fibers [birefringent rods in images (b) and (d), respectively]. Images (a) and (c) are the POM photographs of the isotropic (a) and anisotropic (c) HPC matrix. White arrows in images (c) and (d) indicate the shear direction. All images were taken under crossed polars. Images were obtained from references [12] (a and b) and [14] (c and d)...

POM images (taken on an Olympus BH2 microscope) of isotropic and anisotropic all-cellulosic based composites are shown in Fig. 15.2. 

Fiber alignment in short fiber composites (SFCs) is very difficult to achieve, however the results obtained with anisotropic aU-cellulosic based composites point out for a simple and new way of producing fiber aligned SFCs with enhanced mechanical properties, as discussed later on. 

Fig. 15.3 Plot of the order parameter, S, for all-cellulosic based composites (2% w/w HPC of Avicel fibers), as a function of the HPC content Isotropic and anisotropic composites are marked [13]...

Table 15.1 Roughness parameters calculated from the respective AFM images of the uncross-linked isotropic all-cellulosic based composites [12]...

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