Tetrafluoroethylene-hexafluoropropylene copolymer
Structural formula | |||||||
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General | |||||||
Surname | Fluoroethylene propylene | ||||||
other names |
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CAS number | 25067-11-2 | ||||||
Brief description |
white to transparent, also yellowish / brownish, odorless solid |
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properties | |||||||
Physical state |
firmly |
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density |
2.1-2.3 g / cm 3 (DIN 53479) |
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Melting point |
253–282 ° C (ISO 11357-1 / 3) |
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solubility |
practically insoluble in water |
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Chemical resistance |
> 420 ° C |
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safety instructions | |||||||
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Tetrafluoroethylene-hexafluoropropylene copolymer ( abbreviated FEP , perfluoro (ethylene-propylene) , and fluorinated ethylene-propylene called) is a copolymer of the monomers tetrafluoroethylene , and hexafluoropropene . It is used when resistance to extreme temperatures or chemicals is required.
history
FEP was made ready for production by DuPont as part of its product developments in the 1950s, in order to bring a fluorocarbon plastic with more favorable thermal molding and processing properties than those of Teflon (PTFE) onto the market. The unprotected abbreviation FEP soon became a synonym for this plastic , which DuPont added to its range of perfluorinated hydrocarbon polymers around 1960 . Since the patent protection rights for DuPont expired, FEP has also been produced by other manufacturers worldwide. In recent literature, instead of FEP, the abbreviation PFEP is used as a synonym for perfluoro (ethylene-propylene), which corresponds better to its chemical structure.
properties
The thermoplastic is not flammable, but decomposes at higher temperatures, such as in the event of a fire, releasing caustic and highly toxic combustion gases.
FEP is stable against almost all chemicals, and the plastic is also extremely weather-resistant and radiation-resistant.
Thermal conductivity | 0.21-0.25 W / Km |
Melting temperature | 257-263 ° C |
Processing temperature | around 370 ° C |
Decomposition temperature | ≥ 420 ° C |
spec. Heat capacity | 1.12-1.17 kJ / K · kg |
min. Operating temperature | −200 ° C |
Max. Operating temperature | 205 ° C |
Areas of application
Fluoroplastics like FEP and PFA are made because of them
- Flexibility,
- good weldability,
- high temperature resistance,
- excellent chemical resistance,
- Usability in the low temperature range,
- Can be used in high-purity applications,
- long service life,
- electrical resistance and
- simple thermoplastic processing
In the chemical processing industry, pharmaceutical industry as well as in semiconductor construction and for exhaust gas purification diverse and proven. They are used as media-resistant liners for lining steel containers and for the construction of dual-laminate containers and tanks, in pipeline construction and for sealing systems. Semi-finished products and plates made of FEP are also used in a variety of ways to protect system components ( valves , heat exchangers , pipelines, etc.) from corrosion .
Individual evidence
- ↑ a b c d e Bola: Safety data sheet FEP dated August 12, 2016
- ↑ a b c d e f g h i j k Reichelt Chemietechnik GmbH & Co. KG .
- ↑ KP Lee, WC Seidel: Pulmonary Response of Rats Exposed to Polytetrafluoroethylene and Tetrafluoroethylene Hexafluoropropylene Copolymer Fume and Isolated Particles . In: Inhalation Toxicology . tape 3 , no. 3 , January 1, 1991, pp. 237-264 , doi : 10.3109 / 08958379109145287 .
- ↑ Sina Ebnesajjad, Pradip R. Khaladkar "Fluoropolymers Applications in Chemical Processing Industries" PDL - Plastics Design Library.
- ↑ a b c AGRU Kunststofftechnik GmbH; http://www.agru.at/de/produkte/halbzeuge/ .
- ^ Thyssen Krupp Plastics; http://www.tkpa.at/technische-kunststoffe/fluorkunststoffe/ .