Electrical insulation Encapsulants

Engineering Uses Now very limited, electrically insulating encapsulated tool grips. Rayon fibres for textiles. 

In addition to aerospace uses, sihca fibers can be twisted into sewing threads and yams for weaving into fabrics. These fabrics are used extensively for heat-resistant clothing, flame curtains for furnace openings, thermocouple protection, and electrical insulation. The cloth can also be used to encapsulate other fibers to produce flexible sheets. 

The polysulphides are frequently used in casting mixes and to a less extent in coating, laminating and adhesive applications. Their value in casting and encapsulation lies mainly with their low curing shrinkage and flexibility in the cured state. Their tendency to corrode copper and the somewhat inferior electric insulation properties of the blends does lead to certain limitations. 

The basic electrical properties of polyurethanes are good, but the polymer s tendency to absorb moisture can change the properties considerably. Polyurethanes are therefore not normally used as electrical insulators. They can be used in potting and encapsulating applications. Any applications involving mains power must be evaluated and approved by the relevant local electrical authority before use in the application. 

Polycarbonates are already commercially produced and have excellent properties including electrical insulation, transparency and heat resistance they have been applied in the manufacture of a range of products, from adhesives to compact disks, encapsulation of electrical and electronic parts, optical lenses and in packaging. Most of these polycarbonates have a poly(oxycarbonyloxy-l,4-phenylene... 

A transistor-based chemical sensor used in aqueous environment must be electrically insulated. An ordinary FET sensor produced with a silicon wafer as starting material has four bare lateral edges, which are made when scribing a processed silicon wafer into FET chips. It has bonding pads on its surface for wires that are connected for the electrical operation of a FET (see Fig. la). It is necessary to insulate the bare lateral sides and bonding pad region, and this is usually done by polymer encapsulation. Because a FET chip is very small and the areas to be insulated are closely located to its ion-sensitive gates, which must... 

JL olymers are increasingly being used in a wide variety of applications in electronics and photonics, most of which use polymers in their traditional role as engineering materials (e.g., circuit boards, molded products, wire and cable insulation, encapsulants, and adhesives). In addition, many other unique applications require material properties that only polymers can provide. Examples include resist materials for the lithographic fabrication of integrated circuits (1C) and polymers for optical recording. These types of applications may be considered passive in the sense that the polymer does not play an active role in the operation of the device or circuit. Rather, it serves some other function such as mechanical support, electrical insulation, or in the case of resists, some intermediate function in the fabrication of the device. 

Use Tire carcasses and linings, especially for tractors and other outsize vehicles electric wire insulation encapsulating compounds steam hose and other mechanical rubber goods pond and reservoir sealant. Latex is used for paper coating, textile and leather finishing, adhesive formulations, air bags, tire vulcanization, self-curing cements, pressure-sensitive adhesives, tire-cord dips, sealants. 

Addition of a filler such as AKO s an alternate method to reduce creep. As shown in Table 3 this filler also increases mechanical strength as well as lowering the coefficient of thermal expansion. The latter aspect can be an important consideration when trying to match material coefficients of expansion in an encapsulating situation. It should also be noted that volume resistivity measurements of unfilled material (see Table 3) indicate these formulations provide satisfactory electrical insulation for encapsulating purposes. 

Polybutadiene diols and hydrogenated polybutadiene diols are used for producing thermoplastic polyurethane elastomers, hydrolytically stable PU elastomers, adhesives, sealants, coatings, encapsulation and electrical insulation polyurethanic products. 

Salensky, G. "Epoxy Resin Systems for Electrical/Electronic Encapsulation Insulation/Circuits" Lake Publishing Corp. Libertyville, IL, 1962, May. 

Important areas of use of epoxy resin powders include the interior and exterior coating of pipes, fittings, fixtures, filter plates, and steel bars for reinforced concrete, as well as the electrical insulation and the encapsulation of electronic components. 

Composites have replaced finished metals in many products. They typically consist of fibrous reinforcement such as glass and carbon or other materials that are encapsulated in a hardened matrix of a resin system. Carbon composite is used in launch vehicles and heat shields for the re-entry phase of spacecraft. Composites have advantages over finished metals. They can be stronger and stiffer than metals per unit weight, highly corrosion resistant, electrically insulating, and much more. 

Dechthummarong, C., Wiengmoon, B., Chenvidhya, D., Jivacate, C., Kirtikara, K. Physical deterioration of encapsulation and electrical insulation properties of PV modules after longterm operation in Thailand. Sol. Energy Mater. Sol. Cells 94(9), 1437-1440 (2010)... 

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