Mechanical effect, cotton fiber properties

E.T.N. Bisanda, and M.P. Ansell, The effect of silane treatment on the mechanical and physical properties of sisal-epoxy composites. Compos. Sci. Technol. 41,165-178(1991). S.H. Zeronian, H. Kawabata, and K.W. Alger, Factors affecting the tensile properties of nonmercerized and mercerized cotton fibers. Text. Res. Inst. 60,179-183 (1990). 

Zeng, Z., Ren, W., Xu, C., Lu, W., Zhang, Y., and Zhang, Y. (2009) Effect of bis(3-triethoxysilylpropyl) tetrasulfide on the crosslink structure interfacial adhesion, and mechanical properties of natural rubber/cotton fiber composites. J. Appl. Polym. Sci., Ill, 437-443. 

Investigations of variation in fiber began some years ago. Using polymeric isocyanate treatment, Maldas, Kokta, and Daneault reported the differences in mechanical properties between aspen, spruce, and birch, and between sawdust, cotton fiber, and fiber from paper pulp processing." Typically, aspen and birch provided better properties than softwood spruce. At 30 percent loading, the highest modulus at 1 percent strain was found with two types of treated pulp, followed by cotton fiber, and then treated sawdust. The effects of isocyanate treatment were more dramatic with sawdust. 

Gel-permeation chromatography" is used to compare the pore structure of jute, scoured jute and purified cotton cellulose. Both native and scoured jute have shown greater pore volumes than cotton. The effects of alkali and acid treatment on the mechanical properties of coir fibers are reported." Scanning electron micrographs of the fractured surfaces of the fibers have revealed extensive fibrillation. Tenacity and extension-at-break decrease with chemical treatment and ultraviolet radiation, whereas an increase in initial modulus and crystallinity is observed with alkali treatment. FTIR spectroscopy shows that the major structural changes that occur when coir fibers are heated isothermally in an air oven (at 100, 150 and 200 °C for 1 h) are attributable to oxidation, dehydration and depolymerization of the cellulose component. 

This also holds for natural fibers such as cotton, wool, hairs, etc. [2]. These fibers are not as small in fiber diameter as the ones discussed above yet they are constructed in a highly complex hierarchical way which provides them not only with unique mechanical properties but also with another set functions which make them of interest for various types of appUcations. The diameter of such natural fibers may well be in the 10-20 p,m range and above hiunan hair, for example, typically has a diameter around 50 (xm. Strong correlations exist between a variety of functions displayed by natural fibers and their molecular and supermolecular structure devised by nature. Natural fibers composed of silk, wool, or cotton are used predominantly for textile applications providing functions such as thermal insulation, wind resistance, exchange of water vapor, etc., but they also contribute in imique ways in fashion design which frequently rehes on the optical effects of silk produced by the prism-shaped fibers. 

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