Ethylene-tetrafluoroethylene copolymer

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Structural formula
Structure of ethylene tetrafluoroethylene
General
Surname Ethylene-tetrafluoroethylene copolymer
other names
  • Poly (ethene- co- tetrafluoroethene)
  • Ethylene tetrafluoroethylene
CAS number 25038-71-5
Monomers / partial structures
Type of polymer

Copolymer

properties
Physical state

firmly

density

1700 kg / m 3

hardness

50-58 (Rockwell R, ASTM D 785)

Elongation at break

250-350%

Thermal conductivity

0.24 W / (m K)

safety instructions
GHS labeling of hazardous substances
no classification available
H and P phrases H: see above
P: see above
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Ethylene-tetrafluoroethylene copolymer ( abbreviation ETFE ) is a fluorinated copolymer consisting of the monomers tetrafluoroethylene and ethylene . Trade names are Dyneon ETFE ( Dyneon ), Tefzel ( DuPont ), Fluon ETFE ( Asahi Glass ) and F-Clear for films.

When ETFE is a derivative of the as Teflon known plastic PTFE . ETFE foils have a low weight and high light and ultraviolet permeability (at 200 nm it is 91.5% for a 25 µm thick foil, while window glass is impermeable at this wavelength).

ETFE is more resistant to beta and gamma radiation than PTFE, especially when exposed to oxygen. However, at 0.03 mass%, it has a water absorption similar to that of PTFE.

use

The roof and facade of the Allianz Arena were made from 2,760 ETFE foil cushions.

Because of their properties, ETFE foils with a thickness of 50 to 250 µm are mainly used in architecture for membrane constructions. The foils are used as roofing for swimming pools such as the National Swimming Center Beijing and greenhouses or other buildings such as Tropical Islands and Gondwanaland in Germany, Eden Project in England, the Beijing National Stadium ( bird's nest ), the Mercedes-Benz Stadium in Atlanta (USA) and the 150 m high tent construction of Khan Shatyr used in Kazakhstan. It is also important for football stadiums such as Allianz Arena , HDI-Arena , PGE Narodowy in Warsaw or the Kiev Olympic Stadium .

Due to its good resistance to many aggressive chemicals (e.g. acids, aromatic hydrocarbons), ETFE is used as a coating material for chemical devices and containers and as a material for valves, fittings and hoses. The temperature resistance (max. 150 ° C) is lower than that of PTFE.

Because of the low dielectric constant (2.3 at 10 GHz to 2.6 below 100 kHz), combined with an acceptable dielectric loss factor (max.0.023 at 100 MHz) and the high dielectric strength (up to 80 kV / mm) and ultraviolet resistance (influence of Pre-discharges ) it is well suited as an insulating material for wire and cable insulation in electrical engineering / electronics, also for aerospace.

ETFE is processed into protective coatings for fiber optic cables. Another application is the protection of thin-film solar cells by lamination with ETFE foil.

Individual evidence

  1. a b c d Revista TA 40 - ETFE ( Memento from March 9, 2013 in the Internet Archive ).
  2. Data sheet Poly (ethylene-co-tetrafluoroethylene) from Sigma-Aldrich , accessed on October 15, 2013 ( PDF ).
  3. This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
  4. DuPont Tefzel Fluoropolymer: Properties Handbook ( Memento of November 28, 2010 in the Internet Archive ) (PDF; 475 kB), p. 25.
  5. DuPont® Tefzel® fluoropolymer: Properties Handbook ( Memento of November 28, 2010 in the Internet Archive ) (PDF; 475 kB), p. 17
  6. Super Bowl 2019 under an ETFE film roof from Bavaria. Retrieved May 6, 2020 .
  7. Frank Molter: Technically and aesthetically at its best . In: VDI-Nachrichten . No. 23 , June 8, 2012, p. 4 ( vdi-nachrichten.com ).
  8. DuPont Tefzel Fluoropolymer: Properties Handbook ( Memento of November 28, 2010 in the Internet Archive ) (PDF; 475 kB), p. 18.
  9. Frank Konrad: Planning of photovoltaic systems: Basics and project planning . 2nd Edition. Vieweg + Teubner, 2008, ISBN 978-3-8348-0586-7 , pp. 49 ( limited preview in Google Book search).