Applications silicones

Where employed for BW applications, silicone emulsion strengths, emulsion stability, spreading coefficients, and effectiveness rates may vary considerably and the preferred product should be identified by comparative evaluation. 

Current market trends indicate a gaining momentum of corrosion and temperature-resistant MEMS devices for the use in mass market applications. Silicon-on-insulator material properties make way for a whole new range of uses and applications while being available in sufficiently large quantities to satisfy large volume production requirements. A breakthrough of these devices can be expected through automotive applications, if they can meet the price pressure. 

Electrical applications silicon carbide in, 22 539 silver in, 22 658 Electrical behavior... 

The unusual properties of silicones make them useful for some special applications as lubricants (20). They are relatively resistant to deterioration by heat or oxidation, and have the desirable properties of high viscosity index, low pour point, and low volatility. They may promote wear in steel-to-steel bearing surfaces under conditions of sliding friction, and are not generally useful for such applications. Silicones are satisfactory lubricants in antifriction bearings and in some bearing combinations other than steel sliding on steel. 

The silicon used for making solid-state semiconductor devices such as transistors, computer chips, and solar cells must be ultrapure, with impurities at a level of less than 10 7% (1 ppb). For electronic applications, silicon is purified by converting it to SiCl4, a volatile liquid (bp 58°C) that can be separated from impurities by fractional distillation and then converted back to elemental silicon by reduction with hydrogen ... 

Applications. Silicon nitride is die leading material for components in advanced automotive, diesel, and gas turbine engines. The range of potentially useful ceramic parts includes both static structural components and dynamic ones such as turbocharger rotors, gasifier turbine rotors, valves, valve guides, valve seats, piston components, cam followers, fuel injector links, and bearings. Some of these parts have been commercialized, others are... 

In other useful applications, silicon nitride bearings have been found to offer excellent performance silicon nitride cutting tool inserts are a commercial product wear parts such as sand blast nozzles, seals, and die liners are also commercially produced the superior performance of heat exchangers has been demonstrated and there are also military applications. 

Substrates The substrates in microelectronics are mainly Si wafers. For mobile applications, silicon-on-insulator (SOI) wafers increasingly replace bulk Si wafers and for very specific high-frequency applications, III-V compound semiconductors (e.g., GaAs) are used. The majority of substrates in microfabrication are Si wafers, but metal, glass, and ceramic substrates are also common. Particularly when using glass, quartz, and ceramic wafers in CMP processes, it has to be taken into account that they are brittle and easy to break. The situation is worse when the material is also under stress induced by deposited layers. For applications where the backside of the wafer has to be structured (e.g., in bulk micromachining), double-side polished substrates are employed. 

MAJOR POLYMER APPLICATIONS silicone, polyurethanes, epoxy, PE, PP... 

Major polymer applications silicon wafer carriers, pump, pipes, fittings, filtration, tubing, column packing, marine coatings, wear resistant products, coating for hostile environments, automotive weather seals for doors and windows... 

Starting with the silicone elastomer hydrocephalus shunt in 1955, silicone elastomer has become widely used as a soft, flexible, elastomeric material of construction for artificial organs and implants for the human body. When prepared with controls to assure its duplication and freedom from contamination, specific formulations have excellent biocompatibility, biodurability, and a long history of clinical safety. Properties can be varied to meet the needs in many different implant applications. Silicone elastomer can be fabricated in a wide variety of forms and shapes by most all of the techniques used to fabricate thermosetting elastomers. Radiopacity can be increased by fillers such as barium sulfate or powdered metals. It can be sterilized by ethylene oxide, steam autoclave, dry heat, or radiation. Shelf-life at ambient conditions is indefinite. When implanted the host reaction is typically limited to encapsulation of... 

Superhard compounds are obviously formed by a combination of the low atomic number elements boron, carbon, silicon, and nitrogen. Carbon-carbon as diamond, boron-nitrogen as cubic boron nitride, boron-carbon as boron carbide, and silicon-carbon as silicon carbide, belong to the hardest materials hitherto known. Because of their extreme properties and the variety of present and potential commercial applications, silicon carbide (SiC) and boron carbide (B4C) are, besides tungsten carbide-based hard metals, considered by many as the most important carbide materials. 

Applications requiring low adhesion take advantage of the surface properties of the methyl groups (see Mould adhesion and fouling). They include liquid silicone rubber (LSR) used in moulding applications, silicone Release coatings to dispense organic Pressure-sensitive adhesives (PSA) and silicone PSAs. 

H. Maruyama, M. Dogawa and H. Sano ed.. Silicone and its Applications Silicone to sono Ooyo), Toshiba Silicone Co. Ltd., 1988. 

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