Synthetic fibers inorganic

In Chapter 2 we introduce some basic concepts from mineralogy and materials sicence before describing several mineral and synthetic fibrous inorganic materials. In Chapter 3 we outline the physiology of the human lung, cellular biology and the diseases associated with asbestos exposure—the pertinent information for discussions of the health effects of asbestos and other inorganic fibers. 

The entire spectrum of inorganic fibers can be divided into two classes, based on differences in the crystallinity of the solids (Ray, 1978). Synthetic fibers have been known as man-made mineral fibers (MMMF) and manmade vitreous fibers (MMVF). But fibrous materials can be approached or divided in other ways. For example, in the Concise Encyclopedia of Chemical Technology (1985) the entry for chemical fibers includes both manmade and natural polymers, with the discussion centering on carbon-based compounds such as acetates, acrylics, and cellulose. Fibers of other inorganic compounds were not mentioned in the encyclopedia under this entry, but silica glass fibers were described under the heading Optical Fibers. ... 

A division based on crystallinity facilitates our discussions of both mineral and synthetic fibers by accentuating the morphology of the fibrous object rather than its source or composition. Further, although both amorphous and crystalline mineral fibers are known, most of these used in commerce—and certainly the best known—are crystalline. The opposite is true for synthetic or man-made inorganic fibers (MMIF). The fibers used in commerce are predominantly amorphous. 

MMMF are synthetics that have crystalline rather than amorphous structures. Not surprizingly, early examples are reminiscent of the naturally occurring fibers synthetic chrysotile (lander and Wuhrer, 1938) and needles of amphibolelike composition and crystal structure (Shell et al., 1958). However, the bulk of the crystalline synthetic fibers, both in use and under investigation, do not have mineral equivalents therefore, we chose to use the term whiskers to distinguish crystalline man-made inorganic fibers from their natural relatives. 

Manufacture of inorganic materials as fibers is now common. Industry has developed fibers to respond to a range of technological demands. In the process the new fibrous materials have often provided impetus for innovation and development of new uses. The study of synthetic fibers is a rapidly expanding area of research. A variety of sources such as the Journal of... 

The single largest use of ammonia is its direct apphcation as fertdizer, and in the manufacture of ammonium fertilizers that have increased world food production dramatically. Such ammonia-based fertilizers are now the primary source of nitrogen in farm soils. Ammonia also is used in the manufacture of nitric acid, synthetic fibers, plastics, explosives and miscellaneous ammonium salts. Liquid ammonia is used as a solvent for many inorganic reactions in non-aqueous phase. Other apphcations include synthesis of amines and imines as a fluid for supercritical fluid extraction and chromatography and as a reference standard in i N-NMR. 

Commodities 40% ( 720 million) Petrochemicals Plastics and synthetic rubber Synthetic fibers Fertilizers Other inorganic chemicals ... 

The chemistry of ammonia and the ammonium ion is vast ammonia is of immense industrial importance and is produced in larger molar quantities than any other chemical. More than 80% of the ammonia produced is used in fertilizers, with additional uses including the synthesis of explosives, the manufacture of synthetic fibers (such as rayon, nylon, and polyurethanes), and the synthesis of a wide variety of organic and inorganic compounds. As described in Chapter 6, liquid ammonia is used extensively as a nonaqueous ionizing solvent. 

Worldwide production of fibers was c t. 45 10 t/a in 1993, of which ca. 20% was inorganic fibers. Whereas at the turn of the twentieth century the fibers utilized were almost exclusively natural fibers (organic fibers cotton, sheep s wool and silk inorganic fibers asbestos), by 1993 the proportion of synthetic fibers had grown to ca. 50%. This trend appears to parallel the increasing world population and the consumer behavior coupled therewith. 

Paints, varnishes, colors, and fillers Other chemicals and allied products Industrial inorganic chemicals Industrial organic chemicals Vegetable and animal oils and fats Synthetic rubber Synthetic fibers... 

Raw material used Wool synthetic fibers, chemicals for treating Iron ore, limestone, recycled scrap Inorganic and organic chemicals Chemical substances, e.g., solvents and acids ... 

Inorganic dremicals manufacture Plastics and synthetic fiber manufacture... 

Nitric acid is one of the most widely used industrial chemicals. It is employed in the production of fertilizers, explosives, dyes, synthetic fibers, and many inorganic and organic nitrates and as a common laboratory reagent. 

Polyvinyl chloride fiber has a strong resistance to inorganic chemicals, and it swells or dissolves only in a limited number of organic liquids. Weather resistance is also high when it is compared with that of other synthetic fibers such as nylon 6 and vinylon. 

Brunauer et al. [155] classified the sorption isotherms into five different types (see Figure 4.12). The sorption isotherms of the hydrophilic polymers, such as natural fibers and foods, are of type II. The isotherms of the less hydrophilic rubbers, plastics, synthetic fibers, and foods rich in soluble components are of type III. The isotherms of certain inorganic materials (such as aluminum oxides) are of type IV. For many materials, however, the sorption isotherms cannot be properly classified since they belong to more than one type. 

A large volume of data of equilibrium moisture content appears in the literature. Data for more than 35 polymeric materials, such as natural fibers, proteins, plastics, and synthetic fibers, are given in Ref. [8]. Isotherms for 32 materials (organic and inorganic) are also given in Ref. [92]. The literature is especially rich in sorption isotherms of foods due to the fact that the value of water activity is a critical parameter for food preservation safety and quality. 

The solubility of synthetic fibers in different inorganic or organic solvents depends, as most other properties, on the crystallinity and the chemical constitution of fibers. These differences in solubility can be used to distinguish between synthetic fibers in a simple way. The scheme in Figure 3 shows the way... 

---