Mechanical effect, cotton fiber

Cotton, effect of oxidants on, 462,687 Cotton fiber, ozone damage to, 665 Coulombmetry. See Amperometric analyzers <>i ee mechanism, for liquid-phase ozone-olefin reaction, 72-74, 76 Cydic olefins, 4,60,76 aerosols from, 70-72,83,88 importance of, 104... 

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). 

The reduction of can be explained by the reaction mechanisms of DMDHEU (Chang and Chen, 1996 Han and Chen, 1998 Jang et ai, 1993) and LA (Greenwood, 1987 Yanai, 2001). LA treatment had destroyed some of the cotton crystal stracture, which mmed into apseudo-stable state in the hotwet enviroiunenf The DMDHEU, meanwhile, cross-linked with the cellulose stracture within the destroyed crystal structure and prevented the transformation of cellulose chains from the pseudo-stable state to a crystal structure. As a result, the crystal stracture of the fabric was fixed at the lowest X state. Nevertheless, the SMPU can form a polymer layer on the cotton fibers. It provides good protection to the LA treated cotton, and reduces the effect of the hot-moisture transformation of the crystal stracture from cellulose III to cellulose I. 

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. 

Of particular relevance is the study of dye photodegradation, either on wet or dry cellulose, due to the importance of this effect in the textile industry [89]. Today we know that an increase of the humidity content in the fiber promotes a decrease in the lightfasmess of many dyes. This effect exists both for cotton and other polymers where the dye may be adsorbed or covalently bound [89-91]. It also occurs for wool, although to a smaller extent, since in this substrate the mechanism is essentially reductive, while in cellulose it is an oxidative one [89]. 

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