Example applications, electric

Finally, for practical reasons it is useful to classify polymeric materials according to where and how they are employed. A common subdivision is that into structural polymers and functional polymers. Structural polymers are characterized by - and are used because of - their good mechanical, thermal, and chemical properties. Hence, they are primarily used as construction materials in addition to or in place of metals, ceramics, or wood in applications like plastics, fibers, films, elastomers, foams, paints, and adhesives. Functional polymers, in contrast, have completely different property profiles, for example, special electrical, optical, or biological properties. They can assume specific chemical or physical functions in devices for microelectronic, biomedical applications, analytics, synthesis, cosmetics, or hygiene. 

Electrical Parts. Example applications here are connectors, relays and other electrical and electronic parts. Good electrical... 

For closed-cycle applications, such as for spacecraft, submarines, or transportation vehicles, the combinations of lightweight, reasonable power density, and compact size are favorable features in comparison with equivalent-capacity battery-based systems. In the International Space Station, for example, both electricity and water are provided by fuel cells. Fuel cells have not only been used in space exploration, but also in submarines (because they generate no noise or vibration). They have also been used to recover the energy from methane that is generated by wastewater, by garbage dumps, and more recently in automobiles as an alternative to the IC engine. 

If the generation of heat is concentrated in a small, limited space we speak of local heat sources, which can be idealised as point, line or sheet singularities. For example, an electrically heated thin wire can be treated as a linear heat source. Alongside such technical applications these singularities have significant theoretical importance in the calculation of temperature fields, cf. [2.1]. 

Figure 1 shows an example from electric modulus spectra of the room temperature ionic liquid (an environmental friendly material that have many applications), 1-butyl-1-methylpyrrolidinium bis[oxalato]borate (BMP-BOB) measured over wide temperature (123-300 K) and pressure (0.1-500 MPa) ranges. ... 

Hot-melt adhesives, which belong to thermoplastics (Section 3.3.1), are liquefied by heat supply, for example, in electrically heated nozzles of the application device, and then applied to the adherends. Since the hot-melt cools down very quickly the adherends have to be affixed immediately. The open assembly time of these adhesives, that is, the period of time between the application of the adhesive and the fixing of the adherends, is very short and must not be exceeded. The open assembly time strongly depends on the heat conductivity properties of the adherends the faster they dissipate the heat from the melt, the shorter is the open assembly time. Hot-melt adhesives are available in the form of blocks, rods, films, granulate or even in the form of powder. 

The high electrical resistivity of asbestos fibers is well-known, and has been widely exploited in electrical insulation applications. In general, the resistivity of chrysotile is lower than that of the amphiboles, particularly in high humidity environments (because of the availability of soluble ions). For example, the electrical resistivity of chrysotile decreases from 1 to 2100 MQ/cm in a dry environment to values of 0.01 to 0.4 MQ/cm at 91% relative humidity. Amphiboles, on the other hand, exhibit resistivity between 8,000 and 900,000 MQ/cm... 

Generation of internal energy finds many important applications in engineering. Examples are electric heaters, nuclear reactors, exothermic chemical reactions, etc. In this section we shall consider variable as well as uniform energy generation in flat plates, cylinders, and spheres. Also, the conductivity will be assumed variable in some of these considerations. 

Almost all the coatings applied by this process have a definite function, chiefly electrical insulation, but it can be used for applications that simply require a thick coating with powder. Examples of electrical applications in include small motor stators and rotors, electronic components (capacitors or resistors), transformer casings, covers, laminations, and busbar. Other items coated using fluidized beds include valve bodies used in chemical industries, refinery equipment, and appliance and pump parts. 

---