Fibers silicon containing compounds

A survey of the Hterature [28, 55-62, 66, 67, 69-74] indicates that the most frequent exposure to silicon involves exposure to silica and siUcates mainly in their crystalline forms. Health risks associated with the exposure to other silicon containing compounds were reported in the mortality study of 16.661 man-made mineral fiber workers employed during 1945 to 1963 at one of 17 U.S. manufacturing plants [70]. Fiber exposure... 

For the preparation of technically important metal carbide and metal nitride materials the application of organosilicon compounds as preceramic precursors is advantageous under certain conditions [1-5]. Compared with the conventional metallurgical powder process, one benefit is the utilization of very low process temperatures for the preparation of individual ceramic materials. Another improvement is the high purity of the ceramics obtained from tailor-made preceramic precursors. Usually, after pyrolysis organosilicon compounds afford silicon-containing ceramic powders Likewise, they can also be used under certain conditions for the production of silicon carbide or silicon nitride fibers. 

The supplanting of germanium-based semiconductor devices by silicon devices has almost eliminated the use of indium in the related alloy junction (see Semiconductors). Indium, however, is finding increased use in III—V compound semiconductors such as indium phosphide [22398-80-7] for laser diodes used in fiber optic communication systems (see Electronic materials Fiber optics Light generation). Other important indium-containing semiconductors include indium arsenide [1303-11-3], indium antimonide [1312 -1-0], and copper—indium—diselenide [12018-95-0]. 

Another major source of contamination in an analysis can be the analyst. It depends on what kinds of analytes are being measured, but when trace or ultratrace levels of elements or molecules are being determined, the analyst can be a part of the analytical problem. Many personal care items, such as hand creams, shampoos, powders, and cosmetics, contain significant amounts of chemicals that may be analytes. The problem can be severe for volatile organic compounds in aftershave, perfume, and many other scented products and for silicone polymers, used in many health and beauty products. Powdered gloves may contain a variety of trace elements and should not be used by analysts performing trace element determinations. Hair, skin, and clothing can shed cells or fibers that can contaminate a sample. 

Recently, a new series of fluoro-containing silicone fluids have been introduced. In addition to being nonyellowing softeners, these materials have been found to provide outstanding fiber to metal lubrication and good spreadability on surfaces. These compounds conform to the following structure ... 

The major products containing Si are siliconesf which are polymeric compounds having Si—O bonds. Silicones are used in various industrial fields such as the electric and electronic industries, business machinery and tools, constructions, foods, medical treatments, fibers, plastics, papers, pulps, paints, rubbers, etc. The kind of goods manufactured are three thousand or more, and increasing all the time [2]. Therefore, the number of patent applications for silicones and silanes are many and there are 4000-5000 per year in Japan. The field of organosilicon compounds is the most active of the organometallic compounds [2]. 

Commercial chemical fibers are combustible in nature, and improved FR properties must be considered in actual application. Most FR additives contain bromine (Br), chlorine (Cl), phosphorus (P), antimony, or aluminum. Among them, commonly used additives are additive brominated hydrocarbons and reactive brominated hydrocarbons, nonhalogenated phosphate esters, halogenated phosphate esters, trioxide antimony oxide, pentoxide antimony oxide and sodium derivatives, chlorinated hydrocarbons like chlorinated paraffin, and chlorinated cycloaUphatics. Others include chlorinated or brominated compounds, fluorinated compounds, magnesium carbonate, magnesium hydroxide, melamine, molybdenum compounds, silicone polymer, and zinc borate. Sometimes, polymers are chemically modified, and N, P, Cl, fluorine (F), silicon (Si), and Br elements can be introduced into the polymer main chain [49]. 

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