Fluorine elastomer

Mihtary interest in the development of fuel and thermal resistant elastomers for low temperature service created a need for fluorinated elastomers. In the early 1950s, the M. W. Kellogg Co. in a joint project with the U.S. Army Quartermaster Corps, and 3M in a joint project with the U.S. Air Force, developed two commercial fluorocarbon elastomers. The copolymers of vinyUdene fluoride, CF2=CH2, and chlorotrifluoroethylene, CF2=CFC1, became available from Kellogg in 1955 under the trademark of Kel-F (1-3) (see Fluorine compounds, ORGANic-POLYcm.OROTRiFLUOROETHYLENE Poly(vinylidene) fluoride). In 1956, 3M introduced a polymer based on poly(l,l-dihydroperfluorobutyl acrylate) trademarked 3M Brand Fluorombber 1F4 (4). The poor balance of acid, steam, and heat resistance of the latter elastomer limited its commercial use. 

The technique of passing a gas into a solid which is in the form of tiny granules and thus making the solid behave as if it were a dense, viscous liquid. Fluidised materials may be easily piped from place to place, but a particular application in the rubber industry is the vulcanisation of extruded sections. See Fluid Bed Vulcanisation. Fluorinated Elastomers... 

HFP — Hexafluoropropylene, a monomer used for the production of FEP and other copolymers, such as THY Fluoroplastic and fluorinated elastomers. 

Plazek, 1986 Plazek and Choy, 1989 Plazek and Frund, 1990 Plazek and Chay, 1991) as well as some polybutadienes and fluorinated elastomers (Plazek et al, 1983 Plazek et al., 1988 Plazek and Rosner, 1998). Some nonlinear viscoelastic behavior is discussed. 

In general, elastomer materials are used to seal PEFC, the most prominent being silicones, EPDM rubbers (Ethylene Propylene Diene Monomer class mbber) and fluorinated elastomers [74, 77, 78]. 

Fluorinated elastomers (polymers of hexafluoropropylene or vinylidene fluoride) decompose in the flame but cease to bum after the removal of the igniting source. The thermally stable triazine elastomer is quite inflammable, even in direct flame ... 

Fluorinated elastomers inclnde several types, e.g., fluorocarbons and flnorosilicones. The elastomers can be nsed to 315°C, do not bnm, are unaffected by most chemicals, and have excellent electrical properties. In thermal stability and aging, only the silicones are better. Physical properties are good bnt the cost is high. 

I, Nitrile elastomer (Perbunan) II, fluorinated elastomer (Viton) III, silicone elastomer. 

In the past 10 years fluoroelastomers containing 70-72% fluorine have been introduced. These highly fluorinated elastomers are resistant to the new oxygenated fuels now used in the automobile industry and meet the stringent permeation requirements (33-35) (see Fig. 3). 

Fully fluorinated elastomers Fully fluorinated thermoplastics... 

Since the early stages of their development, a wide range of rubbers has been used as dielectric elastomers. The most commonly used elastomers belong to the silicone, polyurethane, and acrylic families. Other elastomers, such as polyisoprenes, fluorinated elastomers,... 

Desimone and coworkers have developed fluorinated elastomers for a technique coined as pattern replication in nonwetting templates (PRINT), which allows one to fabricate surface-bound or free polymeric structures of virtually any size and shape, with feature sizes reaching well below 100 nm. Figure 5.54 illustrates the PRINT technique, which is analogous to the MIMIC technique, with the use of... 

The behaviour of these polymers when subjected to conditions similar to those encountered below ground in an oil well are compared with a conventional NBR and a fluorinated elastomer in Fig. 2. The... 

The relative speed with which hydrogenated or highly saturated nitriles have appeared on the market commercially has highlighted the need for polymers that fill the performance gap between standard NBRs and the high-performance fluorinated elastomers. This is an area of polymer and technology development that is in a rapid state of change and more candidates for this market, defined by the automobile and oil exploration industries, are sure to appear. 

Fluorinated elastomers are usually looked upon as being best equipped to withstand these conditions. The level of resistance can depend on the degree of fluorination of the backbone of the elastomer and the detaUs of the compounding used. Advances in steam resistance have recently been made with the introduction of high-fluorine peroxide-curable Viton GF and also peroxide-curable TFE/P Aflas 150P. 

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