Organic insulating materials

Tucker DS. Hurley GF, Kennedy JC (1986) Mechanical properties of three candidate organic insulator materials for fusion reactors. In Hartwig G, Evans D (eds) Nonmetallic materials and composites at low temperature, vol 3. Plenum, New York, p 21... 

Organic insulating materials are generally subject to temperature dependent deterioration during their operational lifetime. The relevant chemical processes are complicated and may be described (with a certain simplification) as slow oxidation which introduces acid groups into the polymeric insulation, the loss of plasticizer, oxygen cross-linking of polymer chains and internally catalysed depolymerization of plastic insulation. 

The first main feature of increased safety is the reduction of operational temperatures for (organic) insulating materials in order to achieve a higher lifetime in service and to reduce the probability of an early breakdown of the insulation in the windings of motors, generators, transformers (and inductances). 

Components such as terminal blocks, bushings or busbar insulators with organic insulating materials show maximum service temperatures far below... 

Resinous silicones can be made by polymerizing silicones into cross-linked molecules. These resinous materials are used for electric insulation. They have excellent dielectric properties and are stable at operating temperatures at which the usual organic insulating materials decompose rapidly. The use of these materials permits electric machines to be operated with increased loads. 

Steel Halogenated organic insulation Materials as chlorinated diphenyl 0.1 -2.4% (NH3)2C(,H3NHPh, o-MeH4NH2, or p - N02C(,H4NH2... 

Foams. Sulfur can be foamed into a lightweight insulation that compares favorably with many organic foams and other insulating materials used in constmction. It has been evaluated as thermal insulation for highways and other appHcations to prevent frost damage (63) (see Eoamed plastics Insulation, thermal). 

This includes organic fibrous materials on a cellulose base such as paper, pressboard, cotton, cotton cloth and natural silk etc., impregnated with lacquers or immersed in an insulating liquid. The impregnation or immersion ensures that the oxygen content of the air does not affect... 

This comprises composite materials on mica, glass fibre and asbestos bases, impregnated or glued together with silicone resins or silicone elastomer. These materials must not contain any organic fibrous materials such as paper or cloth backing, which is covered under class B and even F insulation systems. 

SSIMS has been used in the TOP SSIMS imaging mode to study very thin layers of organic materials [3.32-3.36], polymeric insulating materials [3.37], and carbon fiber and composite fracture surfaces [3.38]. In these studies a spatial resolution of ca. 80 nm in mass-resolved images was achieved. 

Insulation that has been impregnated with heavy oil—or any other organic liquid—should be removed as soon as possible before tbe oil ignites. If oil is left in contact with insulation materials, the auto-ignition temperature is lowered by 100-200°C [8] (see Section 7.3.2). 

Fire properties of insulation materials range from the highest to the lowest, from non-combustible to flammable with toxic fume emission. Generally, inorganic materials tend to be non-combustible while organic (or oil-based) materials are combustible, but many have surface treatments to improve their fire-safety rating. 

Depth profiling may be conducted on insulating materials, and XPS can perform thickness measurements on organic films such a lubricants on magnetic media. It is capable of measuring surface contamination by both inorganic and organic materials on a wide variety of substrates. 

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