Cellulose and Other Fibers

Each year photosynthetically produced cellulose (the most common organic compound on Earth) amounts to 1.3 billion tonnes. Cellulose is a polysaccharide 

The natural fiber industries employ worldwide millions of people, especially in developing countries and their products are processed in many small and large industries. The promotion of the use of natural fibers as a CO2 neutral resource could contribute to a reduction of climate-endangering gases, and the year 2009 has been assigned by the UN to be the international year of natural fibers. Production of man-made fiber from cellulose (cellulosics), of which rayon accounts for by far the largest portion, was 3.5 million tormes in 2008. Cotton production has grown steadily. It is estimated to reach 25 million tons in the season 2010/2011. 

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The addition of asbestos fibers at one time provided excellent thixotropic adhesive formulations, especially at elevated temperatures. However, health and environmental regulations have severely limited the use of this material. Today, fumed silica, precipitated calcium carbonate, certain clays, and cellulose and other fibers offer thixotropic properties at relatively low levels of loading. 

FYARESTOR 345 is a highly effective, economical, water-based flame retardant designed for non-woven products made from polyester, cellulose and other fibers. 

Ruminant A mammal that possesses four compartments in the stomach (rumen, reticulum, omasum, abomasum) and is capable of digesting fiber-rich foods. The rumen contains a wide range of anaerobic microorganisms capable of converting cellulose and other fibers—except lignin—into volatile fatty acids that are used as a source of energy. 

Other fibrous and porous materials used for sound-absorbing treatments include wood, cellulose, and metal fibers foamed gypsum or Pordand cement combined with other materials and sintered metals. Wood fibers can be combined with binders and dame-retardent chemicals. Metal fibers and sintered metals can be manufactured with finely controlled physical properties. They usually are made for appHcations involving severe chemical or physical environments, although some sintered metal materials have found their way into architectural appHcations. Prior to concerns regarding its carcinogenic properties, asbestos fiber had been used extensively in spray-on acoustical treatments. 

Nonwovens are widely utilized as separators for several types of batteries. Lightweight, wet laid nonwovens made from cellulose, poly (vinyl alcohol), and other fibers have achieved considerable success as separators for popular primary alkaline cells of various sizes. The key nonwoven attributes include consistently uniform basis weight, thickness, porosity and resistance to degradation by electrolytes. Nonwovens are also successfully employed as separators in NiCd s. 

The Freundlich isotherm, where the dye in fiber D, is directly proportional to (D,)- and a plot of log D against log D, gives a straight line, is generally found with cellulosic and other ionic hydrophobic fibers. 

Vegetable fibers inelude the most important of all textile fibers eotton - together with flax, hemp, jute and other fibers which have produeed by plants. They are base on cellulose, the material used by nature as a stmctural material in the plant world. Animal fibers include wool and other hair-like fibers, and fibers sueh as silk, produced as filaments by cocoonspinning creatures. These animal fibers are based on proteins, the eomplex substanees from which much of the animal body is made [72]. 

Since the 1960 s many researchers have been concerned with the development of feasible and industrially useful methods for the synthesis of cellulose graft copolymers3, 4. Recent investigations have shown that the most efficient approach to this problem involves free radical polymerization initiated by redox systems5. An impressive example is the industrial production of mtilon (cellulose-polyacrylonitrile graft copolymer) and other fibers, particularly those with ion-exchange and acid-resistant properties6"8. ... 

SYNTHETIC RUBBER, CELLULOSIC AND OTHER MANMADE FIBERS, EXCEPT GLASS... 

Since the cellulose and other major constituents of natural fibers are insoluble molecules and are deposited within the cell walls in an intimate physical mixture of great structural complexity, formation of this requisite physical association can be achieved only by diffusion of these enzymes to susceptible sites on the gross surfaces of the fiber or the microfibrillar and molecular surfaces within the fiber wall. Thus, any structural feature... 

One possible explanation for these different modes of cellulose depolymerization in the same species of wood is that the cellulolytic enzyme molecules of Poria monticola are smaller than those of Polyporus versicolor and for that reason would be able to penetrate and act in regions of the fine structure of the fibers that are not accessible to those of the latter fungus. This hypothesis has led to efforts (as yet incomplete) to determine the molecular size of the cellulolytic enzyme proteins of these two organisms. Another possible explanation is that the initial dissolution of cellulose and other cell-wall polysaccharides is accomplished by catalysts that are not enzyme proteins and therefore could be substantially smaller in molecular size. Halliwell (21) has described experiments on the... 

High performance composite materials can be obtained with a good level of dispersion, mainly when the hierarchical structure of cellulose and use of a water soluble polymer to form the matrix are considered. For most materials applications, the main biopolymers of interest are cellixlose and starch. The ease of adhesion that occurs in cellulose has contributed to its use in paper and other fiber-based composite materials. 

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