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| | Greetings. The writer's name is Phebe and she feels comfy when individuals use the full title. Doing ceramics is what her family members and her enjoy. Hiring is her working day over the counter std test job now but std home test she's usually needed her own company. Her spouse and her live in Puerto Rico but she will have to move one working day or an additional.<br><br>Feel std testing at home free to surf to my [http://Laglc.convio.net/site/PageServer?pagename=YH_STD_Testing_and_Treatment website] [http://formalarmour.com/index.php?do=/blog/2752/valuable-guidance-for-successfully-treating-yeast-infections/add-comment/ std testing at home] |
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| <!-- please see [[Polytetrafluoroethylene (data page)]] for the full transcluded template. -->
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| | Verifiedfields = changed
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| | verifiedrevid = 477171888
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| | ImageFile = Teflon structure.PNG
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| | ImageSize = 130px
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| | ImageFile1 = Perfluorodecyl-chain-from-xtal-Mercury-3D-balls.png
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| | ImageSize1 = 250px
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| | IUPACName = poly(1,1,2,2-tetrafluoroethylene)<ref>{{cite web | url=http://www.ebi.ac.uk/chebi/searchId.do?chebiId=53251 | title=poly(tetrafluoroethylene) (CHEBI:53251) | accessdate=July 12, 2012}}</ref>
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| | SystematicName =
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| | OtherNames = Syncolon, Fluon, Poly(tetrafluoroethene), Poly(difluoromethylene), Poly(tetrafluoroethylene)
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| | Section1 = {{Chembox Identifiers
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| | Abbreviations = PTFE
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| | ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}
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| | ChemSpiderID =
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| | CASNo_Ref = {{cascite|correct|CAS}}
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| | ChEBI_Ref = {{ebicite|changed|EBI}}
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| | ChEBI = 53251
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| | PubChem =
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| | PubChem_Ref =
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| | CASNo = 9002-84-0
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| | KEGG_Ref = {{keggcite|changed|kegg}}=
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| | KEGG = D08974}}
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| | Section2 = {{Chembox Properties
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| | Formula = (C<sub>2</sub>F<sub>4</sub>)<sub>n</sub>
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| | Young's Modulus = 0.5 GPa
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| | Density = 2200 kg/m<sup>3</sup>
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| | MeltingPt = 600 K
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| | ThermalConductivity = 0.25 W/(m·K)
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| }}
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| | Section7 = {{Chembox Hazards
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| | NFPA-H = 1
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| | NFPA-F = 0
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| | NFPA-R = 0
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| }}
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| }}
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| '''Polytetrafluoroethylene''' ('''PTFE''') is a synthetic [[fluoropolymer]] of [[tetrafluoroethylene]] that has numerous applications. The best known brand name of PTFE is '''Teflon''' by [[DuPont]] Co.
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| PTFE is a [[fluorocarbon]] solid, as it is a high-[[molecular weight|molecular-weight]] compound consisting wholly of [[carbon]] and [[fluorine]]. PTFE is [[hydrophobic]]: neither water nor water-containing substances wet PTFE, as fluorocarbons demonstrate mitigated [[London dispersion force]]s due to the high [[electronegativity]] of fluorine. PTFE has one of the lowest coefficients of [[friction]] against any solid.
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| PTFE is used as a [[non-stick]] coating for pans and other [[cookware]]. It is very non-reactive, partly because of the strength of [[carbon–fluorine bond]]s and so it is often used in containers and pipework for reactive and corrosive chemicals. Where used as a [[lubricant]], PTFE reduces friction, wear and energy consumption of machinery. It is also commonly used as a graft material in surgical interventions.
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| It is commonly believed that Teflon is a spin-off product from [[NASA]] space projects. Although it has been used by NASA, the assumption is incorrect.<ref name="NASASpinOff">[http://www.sti.nasa.gov/tto/spinfaq.htm NASA Spinoff] under Are Tang, Teflon, and Velcro NASA spinoffs?</ref>
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| == History ==
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| {{external media | width = 210px | align = right | headerimage= | audio1 = [http://www.chemheritage.org/discover/media/distillations/160-teflon.aspx “From stove tops to outer space... Teflon touches every one of us some way almost every day.”], Roy Plunkett, [[Chemical Heritage Foundation]]}}
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| [[File:EL-1994-00019.jpeg|thumb|220px|Teflon thermal cover showing impact craters, from NASA Ultra Heavy Cosmic Ray Experiment (UHCRE)]]
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| PTFE was accidentally discovered in 1938 by [[Roy Plunkett]], in New Jersey while he was working for [[Kinetic Chemicals]]. As Plunkett was attempting to make a new [[chlorofluorocarbon]] refrigerant, the [[tetrafluoroethylene]] gas in its pressure bottle stopped flowing before the bottle's weight had dropped to the point signaling "empty." Since Plunkett was measuring the amount of gas used by weighing the bottle, he became curious as to the source of the weight, and finally resorted to sawing the bottle apart. Inside, he found it coated with a waxy white material which was oddly slippery. Analysis of the material showed that it was polymerized perfluoroethylene, with the iron from the inside of the container having acted as a catalyst at high pressure. Kinetic Chemicals patented the new fluorinated plastic (analogous to the already known [[polyethylene]]) in 1941,<ref>{{Cite patent|inventor-last = Plunkett|inventor-first = Roy J|inventorlink = Roy Plunkett|issue-date = 4 February 1941|title = Tetrafluoroethylene polymers|country-code = US|patent-number = 2230654}}</ref> and registered the Teflon trademark in 1945.<ref name="fluoroboom">{{cite news|title = History Timeline 1930: The Fluorocarbon Boom|url= http://www2.dupont.com/Refrigerants/en_US/sales_support/history_1930.html|accessdate =10 June 2009|publisher=''[[DuPont]]''}}</ref><ref>{{cite news|title = Roy Plunkett: 1938|url = http://www2.dupont.com/Heritage/en_US/1938_dupont/1938_indepth.html|accessdate =10 June 2009}}</ref>
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| DuPont, which founded Kinetic Chemicals in partnership with [[General Motors]], was producing over two million pounds (900 tons) of Teflon brand PTFE per year in [[Parkersburg, West Virginia]], by 1948.<ref>American Heritage's Invention & Technology, Fall 2010, vol. 25, no. 3, p. 42</ref> An early use was in the [[Manhattan Project]] as a material to coat valves and seals in the pipes holding highly reactive [[uranium hexafluoride]] at the vast [[K-25]] [[enriched uranium|uranium enrichment]] plant in [[Oak Ridge, Tennessee]].<ref name = "rhodes">
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| {{Cite book|last = Rhodes|first = Richard|authorlink = Richard Rhodes
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| | title = The Making of the Atomic Bomb|publisher = Simon and Schuster
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| | year = 1986|location = New York, New York|page = 494
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| | url = http://books.google.com/books?id=aSgFMMNQ6G4C&printsec=frontcover
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| | accessdate =31 October 2010|isbn = 0-671-65719-4}}</ref>
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| In 1954, French engineer Marc Grégoire created the first pan coated with Teflon non-stick resin under the brand name of [[Tefal]] after his wife Collete urged him to try the material he had been using on fishing tackle on her cooking pans.<ref name="history">"[http://web.archive.org/web/20080214150646/http://home.nycap.rr.com/useless/teflon/index.html Teflon History ]", ''home.nycap.rr.com'', Retrieved 25 January 2009.</ref> In the United States, [[Marion A. Trozzolo]], who had been using the substance on scientific utensils, marketed the first US-made Teflon coated frying pan, "The Happy Pan", in 1961.<ref name="intofire">Robbins, William (21 December 1986) "[http://www.nytimes.com/1986/12/21/us/teflon-maker-out-of-frying-pan-into-fame.html Teflon Maker: Out Of Frying Pan Into Fame ]", ''[[New York Times]]'', Retrieved 21 December 1986 (Subscription)</ref>
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| In the 1990s, it was found that PTFE can be radiation [[cross-linked]] above its melting point in an oxygen free environment.<ref> [http://dx.doi.org/10.1016/0969-806X(94)90226-7 Modification of PTFE by radiation] J.Z. Sun, Y.F. Zhang, X.G. Zhong, X.L. Zhu, Modification of polytetrafluoroethylene by radiation. 1. Improvement in high-temperature properties and radiation stability, Radiat. Phys. Chem. 44 (1994) 655–679.</ref> [[Electron beam processing]] is one example of radiation processing. Cross-linked PTFE has improved high temperature mechanical properties and radiation stability. This is significant because for many years irradiation at ambient conditions has been used to break down PTFE for recycling. <ref>[http://www.e-beamservices.com/chain.htm Electron Beam Processing of PTFE] E-BEAM Services website. Accessed May 21, 2013</ref> The radiation induced chain scissioning allows it to be more easily reground and reused.
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| == Production ==
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| PTFE is produced by [[free-radical]] [[polymerization]] of tetrafluoroethylene. The net equation is:
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| : n F<sub>2</sub>C=CF<sub>2</sub> → 1/n —{ F<sub>2</sub>C—CF<sub>2</sub>}<sub>n</sub>—
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| Because tetrafluoroethylene can explosively decompose to tetrafluoromethane and carbon, special apparatus is required for the polymerization to prevent hot spots that might initiate this dangerous side reaction. The process is typically initiated with [[persulfate]], which homolyzes to generate sulfate radials:
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| :[O<sub>3</sub>SO-OSO<sub>3</sub>]<sup>2-</sup> <math>\overrightarrow{\leftarrow}</math> 2 SO<sub>4</sub><sup>-</sup>
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| The resulting polymer is terminated with [[sulfate ester]] groups, which can be hydrolyzed to give OH-[[end-group]]s.<ref name=Ullmann>D. Peter Carlson and Walter Schmiegel "Fluoropolymers, Organic" in Ullmann's Encyclopedia of Industrial Chemistry 2000, Wiley-VCH, Weinheim. {{DOI|10.1002/14356007.a11_393}}</ref>
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| Because PTFE is poorly soluble in almost all solvents, the polymerization is conducted as an emulsion in water. This process gives a suspension of polymer particles. Alternatively, the polymerization is conducted using a surfactant such as [[PFOS]].
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| == Properties ==
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| [[File:100 0783.JPG|thumb|right|PTFE is often used to coat [[non-stick pan]]s as it is [[hydrophobic]] and possesses fairly high heat resistance.]]
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| PTFE is a [[thermoplastic]] [[polymer]], which is a white solid at room temperature, with a density of about 2200 kg/m<sup>3</sup>. According to DuPont, its melting point is {{convert|600|K}}.<ref name=dupont>[http://www2.dupont.com/Teflon_Industrial/en_US/tech_info/techinfo_compare.html Fluoropolymer Comparison – Typical Properties] Retrieved 10 September 2006.</ref> It maintains high strength, toughness and self-lubrication at low temperatures down to {{convert|5|K}}, and good flexibility at temperatures above {{convert|194|K}}.<ref name=ptfe_handbook>[http://www.rjchase.com/ptfe_handbook.pdf Teflon PTFE Properties Handbook] Retrieved 11 October 2012.</ref> PTFE gains its properties from the aggregate effect of [[carbon-fluorine bond]]s, as do all fluorocarbons. The only chemicals known to affect these carbon-fluorine bonds are certain [[alkali metal]]s and most highly reactive [[fluorinating agent]]s.<ref>[http://web.archive.org/web/20080704112712/http://www.plastechcoatings.com/dupont_teflon_coating.html DuPont Teflon® Coatings]. plastechcoatings.com</ref>
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| {| class="wikitable" style="text-align:center;"
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| |-
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| ! Property
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| ! Value
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| |-
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| | Density
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| | 2200 kg/m<sup>3</sup>
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| |-
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| | [[Melting point]]
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| | 600 K
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| |-
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| | [[Thermal expansion]]
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| | 135 · 10<sup>−6</sup> K<sup>−1</sup> <ref>{{cite web|url=http://www.engineershandbook.com/Tables/plasticthermalexp.htm|title=Reference Tables – Thermal Expansion Coefficients – Plastics}}</ref>
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| |-
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| | [[Thermal diffusivity]]
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| | 0.124 mm²/s <ref>{{cite journal |author= J. Blumm, A. Lindemann, M. Meyer, C. Strasser | title= Characterization of PTFE Using Advanced Thermal Analysis Technique |journal= [[International Journal of Thermophysics]]| volume=40 |issue=3–4 |page=311 | year= 2011|doi= 10.1007/s10765-008-0512-z |bibcode = 2010IJT....31.1919B }}</ref>
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| |-
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| | [[Young's modulus]]
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| | 0.5 GPa
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| |-
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| | [[Yield strength]]
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| | 23 MPa
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| |-
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| | Bulk resistivity
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| | 10<sup>16</sup> Ω·m <ref>{{cite web|url=http://www.microwaves101.com/encyclopedia/PTFE.cfm|title=Microwaves101 – Polytetrafluoroethylene}}</ref>
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| |-
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| | Coefficient of friction
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| | 0.05–0.10
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| |-
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| | [[Dielectric constant]]
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| | ε=2.1,tan(δ)<5(-4)
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| |-
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| | Dielectric constant (60 Hz)
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| | ε=2.1,tan(δ)<2(-4)
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| |-
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| | [[Dielectric strength]] (1 MHz)
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| | 60 MV/m
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| |}
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| The [[coefficient of friction]] of plastics is usually measured against polished steel.<ref>[http://www.matweb.com/reference/coefficient-of-friction.asp Coefficient of Friction (COF) Testing of Plastics] MatWeb Material Property Data Retrieved 1 January 2007.</ref> PTFE's coefficient of friction is 0.05 to 0.10,<ref name=dupont/> which is the third-lowest of any known solid material ([[Aluminium magnesium boride|BAM]] being the first, with a coefficient of friction of 0.02; [[diamond-like carbon]] being second-lowest at 0.05). PTFE's resistance to [[van der Waals force]]s means that it is the only known surface to which a [[gecko]] cannot stick.<ref name="gecko">"[http://web.archive.org/web/20071014063923/http://socrates.berkeley.edu/~peattiea/research_main.html Research into Gecko Adhesion ]", ''[[University of California, Berkeley|Berkeley]]'', 2007-10-14, Retrieved 8 April 2010.</ref> In fact, PTFE can be used to prevent insects climbing up surfaces painted with the material. PTFE is so slippery that insects cannot get a grip and tend to fall off. For example, PTFE is used to prevent ants climbing out of [[formicarium|formicaria]].
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| Because of its chemical inertness, PTFE cannot be [[cross-link]]ed like an [[elastomer]]. Therefore, it has no "memory" and is subject to [[creep (deformation)|creep]]. This is advantageous when used as a [[Seal (mechanical)|seal]], because the material creeps a small amount to conform to the mating surface. However, to keep the seal from creeping too much, fillers are used, which can also improve wear resistance and reduce friction. Sometimes, metal springs apply continuous force to PTFE seals to give good contact, while permitting a beneficially low percentage of creep.{{Citation needed|date=August 2010}}
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| == Applications and uses ==
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| The major application of PTFE, consuming about 50% of production, is for wiring in aerospace and computer applications, e.g. hookup wire, coaxial cables. This application exploits the fact that PTFE has excellent [[dielectric]] properties. This is especially true at high [[radio frequency|radio frequencies]], making it suitable for use as an [[Electrical insulation|insulator]] in [[cable]]s and [[electrical connector|connector]] assemblies and as a material for [[printed circuit board]]s used at [[microwave]] frequencies. Combined with its high melting temperature, this makes it the material of choice as a high-performance substitute for the weaker and lower melting point [[polyethylene]] that is commonly used in low-cost applications.
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| Another major application is for fuel and hydraulic lines, due to its low resistance against flowing liquids. The colder temperatures at high altitudes cause a reduction in flow of these fluids, and coating the interior surfaces of the fuel and hydraulic lines improves flow.<ref name=Ullmann/>
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| In industrial applications, owing to its low friction, PTFE is used for applications where sliding action of parts is needed: [[plain bearing]]s, [[gear]]s, [[slide plate]]s, etc. In these applications, it performs significantly better than [[nylon]] and [[polyoxymethylene|acetal]]; it is comparable to [[ultra-high-molecular-weight polyethylene]] (UHMWPE), although UHMWPE is more resistant to wear than PTFE, for these applications, versions of PTFE with mineral oil or [[molybdenum disulfide]] embedded as additional [[lubricant]]s in its matrix are being manufactured.
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| Its extremely high bulk [[resistivity]] makes it an ideal material for fabricating long-life [[electret]]s, useful devices that are the [[electrostatic]] analogues of [[magnet]]s.
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| [[Gore-Tex]] is a material incorporating a fluoropolymer membrane with micropores. The roof of the [[Hubert H. Humphrey Metrodome]] in [[Minneapolis]], USA, is one of the largest applications of PTFE coatings, using {{convert|20|acre|m2}} of the material in a double-layered white dome, made using fiberglass with a PTFE coating.
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| ===Other===
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| PTFE (Teflon) is best known for its use in coating non-stick [[frying pan]]s and other cookware, as it is [[hydrophobic]] and possesses fairly high heat resistance.
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| [[File:PTFE tapes with pressure-sensitive adhesive backing, rolls of 15 and 25 mm widths.jpg|thumb|right|PTFE tapes with pressure-sensitive adhesive backing]]
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| ===Niche===
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| PTFE is a versatile material that is found in many niche applications.
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| *a film interface patch for sports and medical applications, featuring a pressure-sensitive adhesive backing, which is installed in strategic high friction areas of footwear, insoles, [[ankle-foot orthosis]], and other medical devices to prevent and relieve friction-induced blisters, calluses, and foot ulceration.
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| *Powdered PTFE is used in [[pyrotechnic composition]]s as [[oxidizer]]s together with powdered metals such as [[aluminium]] and [[magnesium]]. Upon ignition, these mixtures form carbonaceous [[soot]] and the corresponding metal [[fluoride]], and release large amounts of heat. Hence they are used as [[infrared decoy flare]]s and [[igniter]]s for [[solid-fuel rocket]] [[propellant]]s.<ref name=koch>{{cite journal|author=E.-C. Koch|title=Metal-Fluorocarbon Pyrolants:III. Development and Application of Magnesium/Teflon/Viton|journal=[[Propellants, Explosives, Pyrotechnics]] |year=2002|volume=27|pages=262–266|doi=10.1002/1521-4087(200211)27:5<262::AID-PREP262>3.0.CO;2-8|issue=5}}</ref>
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| *In optical [[radiometry]], sheets made from PTFE are used as measuring heads in spectroradiometers and broadband radiometers (e.g., [[illuminance]] meters and [[Ultraviolet|UV]] [[radiometer]]s) due to its capability to diffuse a transmitting light nearly perfectly. Moreover, optical properties of PTFE stay constant over a wide range of wavelengths, from UV down to near [[infrared]]. In this region, the relation of its regular transmittance to diffuse transmittance is negligibly small, so light transmitted through a [[diffuser (optics)|diffuser]] (PTFE sheet) radiates like [[Lambert's cosine law]]. Thus, PTFE enables cosinusoidal angular response for a detector measuring the power of optical radiation at a surface, e.g., in solar [[irradiance]] measurements.
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| *coating for certain types of hardened, [[Armour-piercing bullet|armor-piercing bullet]]s, so as to prevent the increased wear on the firearm's rifling that would result from the harder projectile; however, it is not the PTFE itself that gives the bullet its armor-piercing property.<ref>[http://www.guncite.com/ktwint.html].</ref>
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| *High corrosion resistance favors the use of PTFE in laboratory environments as containers, as magnetic stirrer coatings, and as tubing for highly corrosive chemicals such as [[hydrofluoric acid]], which will dissolve glass containers. It is used in containers for storing [[fluoroantimonic acid]], a [[superacid]].{{Citation needed|date=November 2012}}
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| *PTFE tubes are used in gas-gas heat exchangers in gas cleaning of waste incinerators. Unit power capacity is typically several megawatts.
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| * PTFE is also widely used as a [[thread seal tape]] in plumbing applications, largely replacing paste thread dope.
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| *PTFE membrane filters are among the most efficient used in industrial air filtration applications. Filter coated with a PTFE membrane are often used within a [[dust collection system]] to collect [[aerosol|particulate matter]] from air streams in applications involving high temperatures and high particulate loads such as coal-fired power plants, cement production, and steel foundries.
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| *PTFE grafts can be used to bypass [[stenosis|stenotic]] [[artery|arteries]] in peripheral vascular disease, if a suitable autologous [[vein]] graft is not available.
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| == Safety ==
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| The [[pyrolysis]] of PTFE is detectable at {{convert|200|C}}, and it evolves several [[fluorocarbon]] gases<ref name="ewg.org">[http://www.ewg.org/node/8305 Teflon offgas studies|Environmental Working Group]. Ewg.org. Retrieved on 2013-01-01.</ref> and a [[Sublimation (phase transition)|sublimate]]. An animal study conducted in 1955 concluded that it is unlikely that these products would be generated in amounts significant to health at temperatures below {{convert|250|C}}.<ref>{{cite journal |author= Zapp JA, Limperos G, Brinker KC |title= Toxicity of pyrolysis products of 'Teflon' tetrafluoroethylene resin |journal= Proceedings of the American Industrial Hygiene Association Annual Meeting |date=26 April 1955}}</ref> More recently, however, a study documented birds having been killed by these decomposition products at {{convert|202|C}}, with unconfirmed reports of bird deaths as a result of non-stick cookware heated to as little as {{convert|163|C}}.<ref name="ewg.org"/><ref name="abcnews">[http://abcnews.go.com/2020/story?id=124363 Can Nonstick Make You Sick?]. ABC News. 14 November 2003</ref>
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| While PTFE is stable and nontoxic at lower temperatures, it begins to deteriorate after the temperature of cookware reaches about {{convert|260|C}}, and decomposes above {{convert|350|C}}.<ref name=kqat>DuPont, [http://web.archive.org/web/20080117234907/http://www.teflon.com/Teflon/teflonissafe/keyquestions.html#q3 Key Questions About Teflon], accessed on 3 December 2007.</ref> These degradation by-products can be lethal to [[bird]]s, and can cause [[flu-like symptoms]] in humans.<ref name=kqat/> In May, 2003, the environmental research and advocacy organization [[Environmental Working Group]] filed a 14-page brief with the [[U.S. Consumer Product Safety Commission]] petitioning for a rule requiring that cookware and heated appliances bearing non-stick coatings carry a label warning of hazards to people and to birds.<ref name="ewg.orgPetition">[http://www.ewg.org/files/CPSCbirds.pdf Petition to Require Warning Labels|Environmental Working Group]. (PDF) . Retrieved on 2013-01-01.</ref>
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| Meat is usually fried between {{convert|204| and |232|C|F}}, and most oils will start to smoke before a temperature of {{convert|260|C|F}} is reached, but there are at least two cooking oils (refined [[safflower oil]] and [[avocado oil]]) that have a higher [[smoke point]] than {{convert|260|C|F}}. Empty cookware can also exceed this temperature upon heating.
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| === PFOA ===
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| {{Main|Perfluorooctanoic acid}}
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| Perfluorooctanoic acid (PFOA, or C8) is used as a [[surfactant]] in the [[emulsion polymerization]] of PTFE. Overall, PTFE cookware is considered an insignificant exposure pathway to PFOA.<ref>{{cite journal
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| |author=Trudel D, Horowitz L, Wormuth M, Scheringer M, Cousins IT, Hungerbühler K
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| |title=Estimating consumer exposure to PFOS and PFOA
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| |journal=Risk Anal.
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| |volume=28 |issue=2 |pages=251–69 |date=April 2008
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| |pmid=18419647 |doi=10.1111/j.1539-6924.2008.01017.x}}</ref><ref>{{cite web
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| |url=http://www.consumerreports.org/cro/home-garden/kitchen/cookware-bakeware-cutlery/nonstick-pans-6-07/overview/0607_pans_ov_1.htm
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| |title=Nonstick pans: Nonstick coating risks |work=Consumer Reports |accessdate=4 July 2009}}</ref>
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| == Similar polymers ==
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| [[File:PFA structure.PNG|thumb|Teflon is also used as the trade name for a polymer with similar properties, perfluoroalkoxy polymer resin (PFA).]]
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| Other polymers with similar composition are also known by the Teflon trade name:
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| *[[Perfluoroalkoxy]] (PFA)
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| *[[Fluorinated ethylene propylene]] (FEP)
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| These retain the useful PTFE properties of low friction and nonreactivity, but are more easily formable. For example, FEP is softer than PTFE and melts at {{convert|533|K}}; it is also highly transparent and resistant to sunlight.<ref>[http://web.archive.org/web/20100724195156/http://www.texloc.com/closet/cl_fep_properties.htm FEP Detailed Properties], Parker-TexLoc, 13 April 2006. Retrieved 10 September 2006.</ref>
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| == See also ==
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| * [[Magnesium/Teflon/Viton]]
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| * [[Polymer adsorption]]
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| * [[Polymer fume fever]]
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| * [[BS 4994]] PTFE as a thermoplastic lining for dual laminate chemical process plant equipment
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| == References ==
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| {{Reflist|colwidth=30em}}
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| == Further reading ==
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| *{{Cite journal
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| | last = Ellis
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| | first = D.A.
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| | last2 = Mabury
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| | first2 = S.A.
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| | last3 = Martin
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| | first3 = J.W.
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| | last4 = Muir
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| | first4 = D.C.G.
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| | coauthors = Mabury, S.A.; Martin, J.W.; Muir, D.C.G.
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| | year = 2001
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| | title = Thermolysis of fluoropolymers as a potential source of halogenated organic acids in the environment
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| | journal = Nature
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| | volume = 412
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| | issue = 6844
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| | pages = 321–324
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| | doi = 10.1038/35085548
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| | pmid = 11460160
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| }}
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| == External links ==
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| * [http://www.msnbc.msn.com/id/8408729/ EPA: Compound in Teflon may cause cancer] [http://www.msnbc.msn.com/id/8404384], Tom Costello, NBC News, 29 June 2005. (Flash video required)
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| * [http://www.plasmatechsystems.com/about/pubs/Plasma%20Processes%20Polytetrafluoroethylene.pdf Plasma Processes and Adhesive Bonding of Polytetrafluoroethylene]
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| * [http://www.discovery.com/area/skinnyon/skinnyon970606/skinny1.html The Skinny On... Why Teflon Sticks to the Pan] by Hannah Holmes at ''discovery.com''.
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| {{HealthIssuesOfPlastics}}
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| {{DuPont}}
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| {{Plastics}}
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| {{use dmy dates|date=January 2012}}
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| {{DEFAULTSORT:Polytetrafluoroethylene}}
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| [[Category:American inventions]]
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| [[Category:Fluorocarbons]]
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| [[Category:Plastics]]
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| [[Category:Fluoropolymers]]
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| [[Category:Dry lubricants]]
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| [[Category:DuPont]]
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| [[Category:Dielectrics]]
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| [[Category:Pyrotechnic oxidizers]]
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| [[Category:DuPont products]]
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| [[ko:폴리테트라플루오르에틸렌]]
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| [[ml:ടെഫ്ലോണ്]]
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| [[sv:Polytetrafluoreten]]
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