Cellulose fibers definition

Simply put, paper is manufactured by applying a watery suspension of cellulose fibers to a screen that allows the water to drain and leaves the fibrous particles behind in a web. Most modem paper products contain nonfibrous additives, but otherwise they fall within this general definition. Only a few paper products for specialized uses are created without the use of water, using dry forming techniques. The production of pulp is the major source of environmental impacts from the pulp and paper industry. 

It is difficult to find any definitive information that indicates ozone damage as extensive as that suggested in the mri report. The latter identified cotton, nylon, and rayon as particularly susceptible to ozone. The oxidation of cellulose fibers by ozone was the subject of a study in 1952 that showed that dry cotton was not seriously degraded by ambient ozone. In more recent studies, these conclusions were confirmed. The only information available on fibers other than cotton addressed the effect of ozone on modacrylic, acrylic. Nylon 66, and polyester fabrics.The results indicated minimal effects on these fibers. 

In addition to cellulosic and synthetic resins, the present scope of the industry includes vulcanized fiber, casein pla dcs, and regenerated cellulose. This definition has evolved over a period of years. 

Wood-plastic composite (WPC) deck boards are extruded or molded products of a specified shape and, by definition, represent plastic filled with cellulose fiber and other ingredients. In this context wood is a proxy for fibrous materials of plant origin. These materials will be considered in the next chapter. This chapter deals with a plastic component of composite deck boards, with an understanding that the plastic is thermoplastic. 

In native cellulose, the structure develops under conditions of thermodynamic equilibrium and occurs very slowly. For regenerated cellulose, however, not only must the structure be formed rapidly, but also the organization of the macromolecules by crystallization is constrained by the extent of tangling present in the solution. It was suggested by Baker [261] that the structure of cellulose derivatives could be represented by a continuous range of states of local molecular order rather than by definite polymorphic forms of cellulose. This view is supported by the observation that the x-ray diffraction pattern of rayon often reveals both cellulose II and IV components to an extent, depending on the conditions used to make the fiber. Hindeleh and Johnson [262] have described an x-ray diffraction procedure to measure crystallinity and crystallite size in cellulose fibers by which the relative proportions of cellulose II and IV in rayon can be determined. 

Definition Isolated, colloidal crystalline portion of cellulose fibers partially depolymerized acid hydrolysis prod, of purified wood cellulose... 

Classification Cellulosic material Definition Fibers obtained from stems of Corchorus spp., esp. C. capularis Properties Soft, lustrous fibers loses str. when wet Precaution Combustible not self-extinguishing flamm. as dust, may ignite spontaneously when wet... 

Classification Cellulosic material Definition Fibers obtained from leaves of Agave Properties Lt. yel. to reddish hard, strong fibers fineness 300-500 denier sp.gr. 1.3 Toxicology Toxic by inh. dust is irritating to respiratory tract... 

In contrast to conventional cellulosic chemical fibers, lyocell fibers are manufactured without production of a cellulose derivate in either the dissolution or the actual spinning of the cellulose. The name lyocell fibers comprises all fibers that are solvent-spun cellulosics. By definition, an organic solvent applied in the sol-vent-spinning production process consists of a mix of chemicals in water. 

Originally, the word rayon was appHed to any ceUulose-based man-made fiber, and therefore included the cellulose acetate fibers. However, the definition of rayon was clarified in 1951 and includes textiles fibers and filaments composed of regenerated cellulose and excludes acetate. In Europe the fibers are now generally known as viscose the term viscose rayon is used whenever confusion between the fiber and the cellulose xanthate solution (also called viscose) is possible. 

Historically, dietary fiber referred to iasoluble plant cell wall material, primarily polysaccharides, not digested by the endogenous enzymes of the human digestive tract. This definition has been extended to iaclude other nondigestible polysaccharides, from plants and other sources, that are iacorporated iato processed foods. Cellulose [9004-34-6] (qv) is fibrous however, lignin [9005-53-2] (qv) and many other polysaccharides ia food do not have fiberlike stmctures (see also Carbohydrates). 

Rejection Rejection is defined in Background and Definitions. The highest-rejection membranes are those designed for single-pass production of potable water from the sea. The generally accepted criterion is 99.4 percent rejection of NaCl. Some membranes, notably cellulose triacetate fibers are rated even higher. A whole range of membranes is available as rejection requirements ease, and membranes with excellent chlorine resistance and hydrolytic stability can be made with salt rejection over 90 percent. 

Sisson has traced the evolution of current concepts of the crystalline part of cellulose structures. The fiber diagram obtained by X-ray diffraction is now known to be produced by a series of elementary crystals, called crystallites, which have a definite arrangement with respect to the fiber axis. It is also known that the crystallites in regenerated cellulose may be oriented to varying degrees with respect to the fiber axis and that the crystallites in regenerated cellulose and mercerized cotton differ from those in native fibers. These hydrate type crystallites appear to be more reactive chemically than the native type. 

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