ETFE

Summary

Ethylene tetrafluoroethylene (ETFE) is a fluorine-based plastic. It was designed to have high corrosion resistance and strength over a wide temperature range. ETFE is a polymer and its source-based name is poly(ethene-co-tetrafluoroethene). It is also known under the brand name Tefzel. ETFE has a relatively high melting temperature and excellent chemical, electrical and high-energy radiation resistance properties. When burned, ETFE releases hydrofluoric acid.

ETFE
Ethylen-Tetrafluorethylen.svg
Names
IUPAC name
poly(1,1,2,2-tetrafluorobutane-1,4-diyl)
Other names
poly(ethene-co-tetrafluoroethene)
Identifiers
  • 25038-71-5 checkY
ChemSpider
  • none
  • DTXSID10880370 Edit this at Wikidata
  • InChI=1S/C2F4.C2H4/c3-1(4)2(5)6;1-2/h;1-2H2 checkY
    Key: QHSJIZLJUFMIFP-UHFFFAOYSA-N checkY
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references

PropertiesEdit

Useful comparison tables of PTFE against FEP, PFA and ETFE can be found on DuPont's website, listing the mechanical, thermal, chemical, electrical, and vapour properties of each, side by side.[1]

ETFE is effectively the high-strength version of the other three in this group, often featuring slightly diminished capacities in other fields by comparison.

Combustion of ETFE occurs in the same way as a number of other fluoropolymers, in terms of releasing hydrofluoric acid (HF). HF is extremely corrosive and toxic, and so appropriate caution must be exercised.

ETFE film is self-cleaning (due to its nonstick surface) and recyclable. It is prone to punctures by sharp edges and therefore mostly used for roofs.[2] As a film for roofing it can be stretched and still be taut if some variation in size, such as that caused by thermal expansion, were to occur. Employing heat welding, tears can be repaired with a patch or multiple sheets assembled into larger panels.

ETFE has an approximate tensile strength of 42 MPa (6100 psi), with a working temperature range of 89 K to 423 K (−185 °C to +150 °C or −300 °F to +300 °F).[3]

ETFE resins are resistant to ultraviolet light. An artificial weathering test (comparable to 30 years’ exposure) produced almost no signs of film deterioration.[4]

ETFE systems can control light transmission through the use of frit patterns printed on the foil. Thermal and acoustic insulation can be incorporated into an ETFE structure via the use of multi-layer systems which use low-pressure air pumps to create ETFE "cushions".[5]

ApplicationsEdit

 
The Eden Project, Cornwall, UK. Biomes are constructed with ETFE cushions.
 
ETFE roof at Manchester Piccadilly station, Manchester, UK

ETFE was developed by DuPont in the 1970s initially as a lightweight heat resistant film in the aerospace industry.[6] From its development it was largely used infrequently in agricultural and architectural projects.[6] ETFE's first large-scale use architecturally came in 2001 at the Eden Project where ETFE was selected as it can be printed and layered to control solar conditions and because it was found to have a low friction coefficient, which saves on maintenance as dust and dirt do not stick.[6]

An example of its use is as pneumatic panels to cover the outside of the football stadium Allianz Arena or the Beijing National Aquatics Centre (a.k.a. the Water Cube of the 2008 Olympics) – the world's largest structure made of ETFE film (laminate). The panels of the Eden Project are also made from ETFE, and the Tropical Islands have a 20,000 m2 window made from this translucent material.

Another key use of ETFE is for the covering of electrical and fiber-optic wiring used in high-stress, low-fume-toxicity and high-reliability situations. Aircraft, spacecraft and motorsport wiring are primary examples. Some small cross-section wires like the wire used for the wire-wrap technique are coated with ETFE.

As a dual laminate, ETFE can be bonded with FRP as a thermoplastic liner and used in pipes, tanks, and vessels for additional corrosion protection.

ETFE is commonly used in the nuclear industry for tie or cable wraps and in the aviation and aerospace industries for wire coatings. This is because ETFE has better mechanical toughness than PTFE. In addition, ETFE exhibits a high-energy radiation resistance and can withstand moderately high temperatures for a long period. Commercially deployed brand names of ETFE include Tefzel by DuPont, Fluon by Asahi Glass Company, Neoflon ETFE by Daikin, and Texlon by Vector Foiltec.

Due to its high temperature resistance ETFE is also used in film mode as a mold-release film. ETFE film offered by Guarniflon or Airtech International and Honeywell is used in aerospace applications such as carbon fiber pre-preg curing as a release film for molds or hot high-pressure plates.

 
ETFE cushions roof with integrated photovoltaic cells. Munich's municipal waste management department

Notable buildingsEdit

Notable buildings and designs using ETFE as a significant architectural element:

 
National Space Centre, Leicester UK
 
Detail of Beijing National Aquatics Centre showing ETFE exterior cushions

Under constructionEdit

ReferencesEdit

  1. ^ "Fluoropolymer Comparison - Typical Properties DuPont". Archived from the original on November 16, 2018.
  2. ^ "ETFE". Archived from the original on 2013-03-09. Retrieved 2008-02-06.
  3. ^ "Boedeker Plastics, Inc. > Product". www.boedeker.com.
  4. ^ "ETFE". FlexFacades by Structurflex. Retrieved 2019-10-09.
  5. ^ "10 Benefits of Using ETFE Foil In Architecture".
  6. ^ a b c d Lynch, Patrick (2019-04-06). "What is ETFE and Why Has it Become Architecture's Favorite Polymer?". ArchDaily. Retrieved 18 June 2021.
  7. ^ "LASED – LA Stadium & Entertainment District at Hollywood Park".
  8. ^ "Banc of California Stadium Facts | Los Angeles Football Club".
  9. ^ "The Northern Lights Display". BC Place.
  10. ^ Stoelker, Tom (17 August 2012). "STUDIO V Bets on a Curving Lattice Porte-Cochere in Yonkers". Archpaper.com. Architect’s Newspaper. Archived from the original on 2 February 2014. Retrieved 19 January 2014.
  11. ^ "Archived copy". Archived from the original on 2014-10-23. Retrieved 2014-10-22.{{cite web}}: CS1 maint: archived copy as title (link)
  12. ^ Tim Tucker, The Atlanta Journal-Constitution. "LEADOFF: What's next for Mercedes-Benz Stadium roof?". The Atlanta Journal-Constitution.
  13. ^ "Grimshaw completes roller coaster attraction at shanghai disney resort's tomorrowland". 21 November 2017.
  14. ^ "The Global Change Institute - The University of Queensland, Australia". gci.uq.edu.au.
  15. ^ Gruver, Deb (20 August 2014). "New roof will help save jungle exhibit at Sedgwick County Zoo". Wichita Eagle. Retrieved 20 August 2014.
  16. ^ "BNC Network - The region's largest construction intelligence platform".
  17. ^ "Terminal C Canopy and Upper Deck". Retrieved 5 August 2021.
  18. ^ "Latest look at the ETFE cushion canopy installation at TRON Lightcycle Run in Magic Kingdom".

External linksEdit

  • ETFE Resins - Chemours Teflon
  • Ethylene and TFE - Holscot Fluoroplastics Ltd