Elastomers electrical properties

Typical RTV silicone elastomer electrical properties are shown in Table 3. 

Table 3. Typical RTV Silicone Elastomer Electrical Properties.

Electrical Properties. Like unfluorinated siHcone counterparts, fluorosihcone elastomers have inherently good electrical insulating properties. The dielectric properties remain relatively unchanged when the elastomer is exposed to severe environments. 

Plasma processing technologies ate used for surface treatments and coatings for plastics, elastomers, glasses, metals, ceramics, etc. Such treatments provide better wear characteristics, thermal stability, color, controlled electrical properties, lubricity, abrasion resistance, barrier properties, adhesion promotion, wettability, blood compatibility, and controlled light transmissivity. 

C. An interesting property of these elastomers is a stable dynamic performance over a wide temperature range however, the electrical properties ate only average. 

Electrical Properties of Generic Classes of Thermoplastic Elastomers... 

The polymer requires compounding with normal fillers to produce useful compounds. Chlorosulfonated polyethylene (CSM) excels in resistance to attack by oxygen, ozone, corrosive chemicals, and oil, and in addition has very good electrical properties. Electrical stability and resistance to corona and arc are good. The physical properties and abrasion resistance are also good. Light-colored goods made from CSM have excellent color-fastness. Due to the presence of chlorine atoms, this elastomer shows excellent flame resistance. 

Electrical properties — dielectric constant (e), representing polarization dissipation factor (tan 8), representing relaxation phenomena dielectric strength (EB), representing breakdown phenomena and resistivity (pv), an inverse of conductivity — are compared with other polymers in Table 5.14.74 The low dielectric loss and high electrical resistivity coupled with low water absorption and retention of these properties in harsh environments are major advantages of fluorosilicone elastomers over other polymeric materials.74... 

An alternating copolymer of TFE and propylene (TEE/P) and a terpolymer TFE/P/VDF are fluorocarbon elastomers commercially available under the trademark APE AS. They are characterized by improved low-temperature and electrical properties and steam resistance when compared with FKM and are comparable to PPKM in chemical resistance at lower cost (details in next section). TFE/P has the ASTM D1418 and the ISO 1629 designations FEPM, and in ASTM D2000/SAE J200 it is classified as Type/Class HK. 

Electrical Properties. The electrical properties of silicone gels are essentially the same as those of most clean, unfilled silicone elastomers and fluids. Typical values for dielectric constant and dissipation factor when tested at 25°C and 100 Hz are 2.7 to 2.9 and 0.001 to 0.002 respectively. Volume resistivity values, usually, fall in the 10 ohm- centimeter range. 

Butyl rubber exhibits unusually low permeabihty to gases and outstanding resistance to attack by oxygen and ozone. It has excellent chemical inertness, due to the very low residual unsaturation, and good electrical properties because of its nonpolar saturated nature. Butyl rubber has good tear resistance. Butyl elastomers can be tailored to have good thermal stability and vibrational damping eharacteristics. 

Silicone elastomers are noted for high temperature and oxidative stabihty, low temperature flexibility, good electrical properties, and high resistance to weathering and oil. They are used in wire and cable insulation and surgical implants and as material for gaskets and seals. 

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