Polytetrafluoroethylene plastic PTFE

Fillers/reinforcements can be used to increase the thermal conductivity of the material such as glass and metal fibers or spheres. The filter can be a material like PTFE (polytetrafluoroethylene) plastic that has a much lower coefficient of fnction and the surface exposed material will reduce the fiiction. 

Dry chlorine has a great affinity for absorbing moisture, and wet chlorine is extremely corrosive, attacking most common materials except HasteUoy C, titanium, and tantalum. These metals are protected from attack by the acids formed by chlorine hydrolysis because of surface oxide films on the metal. Tantalum is the preferred constmction material for service with wet and dry chlorine. Wet chlorine gas is handled under pressure using fiberglass-reinforced plastics. Rubber-lined steel is suitable for wet chlorine gas handling up to 100°C. At low pressures and low temperatures PVC, chlorinated PVC, and reinforced polyester resins are also used. Polytetrafluoroethylene (PTFE), poly(vinyhdene fluoride) (PVDE), and... 

Plastics. Almost all commercial plastics find some use both dry and lubricated for sliding at low speeds and light loads the most commonly used thermoplastics are nylon, acetal resins, and polytetrafluoroethylene (PTFE). Typical thermosetting resins for bearing appHcations are phenoHcs, polyesters, and polyimides. Table 8 compares the characteristics of plastic bearing materials with those of graphite, wood, and mbber which find use in somewhat similar appHcations. 

The high thermal stability of the carbon-fluorine bond has led to considerable interest in fluorine-containing polymers as heat-resistant plastics and rubbers. The first patents, taken out by IG Farben in 1934, related to polychlorotri-fluoroethylene (PCTFE) (Figure 13.1 (a)), these materials being subsequently manufactured in Germany and the United States. PCTFE has been of limited application and it was the discovery of polytetrafluoroethylene (PTFE) (Figure... 

Fig. 11. Effect of polyolefin primers on bond strength of ethyl cyanoacrylate to plastics. All assemblies tested in accordance with ASTM D 4501 (block shear method). ETFE = ethylene tetrafluoroethylene copolymer LDPE = low-density polyethylene PFA = polyper-fluoroalkoxycthylene PBT = polybutylene terephthalate, PMP = polymethylpentene PPS = polyphenylene sulfide PP = polypropylene PS = polystyrene PTFE = polytetrafluoroethylene PU = polyurethane. From ref. [73].

Besides the spontaneous, complete wetting for some areas of application, e.g., washing and dishwashing, the rewetting of a hydrophobic component on a solid surface by an aqueous surfactant solution is of great importance. The oil film is thereby compressed to droplets which are released from the surface. Hydrophobic components on low-energy surfaces (e.g., most plastics) are only re wetted under critical conditions. For a complete re wetting of a hydrophobic oil on polytetrafluoroethylene (PTFE) by an aqueous solution, the aqueous solution-oil interface tension must be less than the PTFE-oil interface tension... 

ISO 8829 1990 Aerospace - Polytetrafluoroethylene (PTFE) hose assemblies - Test methods ISO 8913 1994 Aerospace - Lightweight polytetrafluoroethylene (PTFE) hose assemblies, classification 204 degrees C/21000 kPa - Procurement specification ISO 9528 1994 Aerospace - Standard-weight polytetrafluoroethylene (PTFE) hose assemblies, classification 204 degrees C/21000 kPa - Procurement specification ISO 9938 1994 Aerospace - Polytetrafluoroethylene (PTFE) hose assemblies, classification 204 degrees C/28 000 kPa- Procurement specification ISO 10502 1992 Aerospace - Hose assemblies in polytetrafluoroethylene (PTFE) for use up to 232 degrees C and 10 500 kPa - Procurement specification ISO 13000-1 1997 Plastics - Polytetrafluoroethylene (PTFE) semi-finished products -Part 1 Requirements and designation... 

ISO 13000-2 1997 Plastics - Polytetrafluoroethylene (PTFE) semi-finished products -Part 2 Preparation of test specimens and determination of properties... 

A variety of natural and synthetic materials are used throughout fuel and lubricant systems. Examples include transfer lines, hoses, fan blades, impellers, small gears, housings, and a host of supporting framework. Some plastics can be degraded by fuels, lubricants, additives, and various petroleum-based compounds. The most resistant material is polytetrafluoroethylene (PTFE). Ryton and Viton are less resistant, but are still quite stable in fuel and lubricant systems. Characteristics of PTFE and Ryton are shown below ... 

The opacity of plastic foams, and polymers with scratched surfaces, is also governed by Fresnel s law. The n value of the gas which occupies the scratch indentation is much lower than that of the polymer. Light may be directed through rods of transparent polymers, such as PMMA. This effect may be enhanced when the rod or filament is coated with a polymer with a different refractive index, such as polytetrafluoroethylene (ptfe). Optical fibers utilize this principle. 

Many semicompatible rubbery polymers are added to increase the impact resistance of other polymers, such as PS. Other comminuted resins, such as silicones or polyfluorocarbons, are added to increase the lubricity of other plastics. For example, a hot melt dispersion of polytetrafluoroethylene (ptfe) in polyphenylene sulfide (PPS) is used as a coating for antistick cookware. 

The family of FPs, also called fluorocarbon plastics, is based on polymers made of monomers composed of fluorine and carbon may also include chlorine atoms in their structure. Specific types include polytetrafluoroethylene (PTFE), polytetrafluoroethylene-cohexafluoro-propylene or fluorinated ethylene propylene (FEP), polytrafluoroethylene-coperfluoropropylvinyl ether (PFA), ethylenetetrafluoroethylene (ETFE). polychlorotrifluoroethylene (PCTFE), ethylene-chlorotri-fluoroethylene (ECTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), perfluoromethylvinylether (PFMV), perfluoroalkoxy (PFA), etc. 

Non-polar plastics such as polytetrafluoroethylene (PTFE), polyethylene (PE), polypropylene (PP), and polystyrene (PS) are more difficult to adhere to. 1,3-butylene glycol diacrylate has shown some efficiency in promoting adhesion to these types of substrates. 

Polymers, which include synthetic materials such as plastics, vinyl, Nylon, polyester, and polytetrafluoroethylene (PTFE) and natural materials such as silk, cotton, starch and cellulose, are used in our lives every day. Since scientists began to control and manipulate polymers in the 19th Century, chemists have created hundreds of durable synthetic polymeric materials from just a few simple building blocks. Experimentation continues today with increasing polymer uses for applications in chemical, instrumentation, mechanical, electrical and electronic industries. 

The behavior of plastics in contact with clean metals in exemplified by the findings of Brainard and Buckley [7] for polytetrafluoroethylene (PTFE). Transfer of PTFE to clean aluminum, nickel, tungsten, copper, iron, tantalum, gold and silver was detected by the Auger electron emis-... 

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