Chitin whiskers

Wei X, Wang K, Chen J (2011) The functional inorganic composites. Prog Chem 23 42-52 Rinki K, Shipra T, Dutta PK et al (2009) Direct chitosan scaffold formation via chitin whiskers by a supercritical carbon dioxide method a green approach. J Mater Chem 19 8651-8655... 

Morin, A., Dufresne, A., Nanocomposites of chitin whiskers from riftia tubes and poly(caprolactone). Macromolecules. 6, 2190-2199 (2002), DOI 10.1021/ma011493a. 

Ahmed Jalal, U., Masahiro, F., Shinichiro, S., Yasuo, G. Outstanding reinforcing effect of highly oriented chitin whiskers in PVA nanocomposites. Carbohydr. Polym. 87, 799-805 (2012)... 

Gopalan, N.K., Dufresne, A., Gandini, A., Belgacem, M.N. Crab shell chitin whisker reinforced natural rubber nanocomposites. 3. Effect of chemical modification of chitin whiskers. Biomacromolecules 4, 1835-1842 (2003)... 

Table 3.1 Sizes of chitin whiskers prepared from different origins...

Chitin (nigin Hydrolytie time (hr) Chitin whisker Length size Width (nm) References... 

Fig. 3.6 TEM (a) [39] and AFM (b) [38] images of a dilute suspension of chitin whiskers and TEM images of individual chitin whiskers obtained by TEMPO method (c) [51] and surface cationization (d) [53]...

Fig. 3.7 Schematic representations for the preparation of raw chitin and chitosan and chitin whiskers...

Recently a microwave technique for efhcient deacetylation of chitin nanowhiskers to a chitosan nanoscaffold has also been reported [65]. A chitosan nanoscaffold in the form of a colloidal solution was obtained from the deacetylation of chitin whiskers under alkaline conditions by using a microwave technique in only 1/7 of the treatment time of the conventional method (Fig. 3.8). Fourier-... 

For the purpose of chitosan nanoparticles preparation, 20 mg chitosan is dissolved in 40 ml of 2.0 % (v/v) acetic acid and 20 ml of 0.75 mg/ml tripolyphosphate TPP is dropped into a beaker at room temperature. After that chitosan solution was sonicated for 5 min and centrifuged for 15 min at 6000 rpm in order to obtain chitosan nanoparticles. These chitosan nanoparticles could be stored in distilled water however, sonication for 10 s should be applied before a further immobilization step. The morphological characterization of the chitin whisker and chitosan nanoparticles can be evaluated by a Transmission Electron Microscopy (TEM) and Nanosizer. 

Fig. 3.11 TEM image of chitin whiskers from crab shell [70]...

In another study Feng et al. [86] presented the stmcture and properties of new thermoforming bionanocomposites based on chitin whiskers-graft-polycaprolac-tone. The synthesized material was characterized by FTIR, SEM, TEM and XRD. The surface and mechanical properties were also determined and discussed. Ha-riraksapitak et al. [87] prepared a neat hyaluronan-gelatin scaffolds and chitin-whisker-reinforced hyaluronan-gelatin scaffolds. The obtained cylindrical scaffolds obtained were about 10 mm in diameter and 2 mm in height, whereas the disc-shaped scaffolds were about 1 mm in thickness these were later cut into a desired shape and size for the mechanical property assessment. 

Thereafter, CWs have been increasingly used in many other polymer matrices. Following processing steps are involved in the manufacturing of polymer/chitin whisker bio nanocomposites. 

Fig. 3.28 Transmission electron micrographs of a dilute suspension of a unmodified, b ASA modified, and c Pl-modified chitin whiskers [141]...

The overall processing for the polymer chitin whiskers nanocomposites is outlined in Fig. 3.29. 

Tensile testing of single crystalline metallic microwhiskers can also be studied following the experimental tensile testing constructed by Brenner and (b) results of whisker fracture strength as a function of whisker size, showed the clear size dependence (Fig. 3.34). The chitin whiskers are usually incorporated into polymer matrix to prepare CWs reinforced polymer nanocomposite. Thus, the mechanical... 

Paillet, M., Dufresne, A. Chitin whiskers reinforced thermoplastic nanocomposites. Macromolecules. 34, 6527-6530 (2001)... 

Lu, Y.S., Weng, L.H., Zhang, L.N. Morphology and properties of soy protein isolate thermoplastics reinforced with chitin whiskers. Biomacromolecules. 5, 1046-1051 (2004)... 

Wu, X., Torres, F.G., Vilaseca, F., Peijs, T. Influence of the processing conditions on the mechanical properties of chitin whisker reinforced poly(caprolactone) nanocomposites. J. Biobased Mater. Bio. 1, 341-350 (2007)... 

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