Langbahn Team – Weltmeisterschaft

Talk:Perfluorocarbon

Untitled

"PFC is 6000 times more effective than carbon-dioxide"

"effective"? at what? is this some dual-meaning chemistry term?
should mention that it can be used as artificial blood and can be breathed if saturated with oxygen. - Omegatron 14:44, Sep 30, 2004 (UTC)

6000 times?

I think they mean 6000 times more potent than CO2 as a greenhouse gas. Link to Kyoto Protocol I guess.

Needs clarification.


Definition of Perfluorocarbon

Perfluorocarbons can refer to both short-chained fluorocarbons (C3F8, for example) and longer chain ones such as PTFE. In general, under the rubric of PFC, the fluoroindustry recognizes three distinct chemical families in addition to the short-chain fluorocarbons: polyfluorinated small molecules (surfactants, for example), polyfluorinated polymer sidechains with hydrocarbon backbones, and the classic per- or polyfluoropolymers.

The manufacturing processes of the longer chain ones have been plagued by PFOA and PFOA precursor impurities and potential breakdown products (such as the 8:2 FTOH molecule erroneously pictured as a perfluorocarbon in the article) which have only recently and partially been addressed see DuPont's Echelon products, for example. These longer chains impurities are not "non-toxic" as is stated in the article EPA stewardship program, but have been associated with cancer and developmental toxicities.

Fixing this with full info and citations will require several edits. I can't get started on this this week, but could address over the coming weeks.

Kristan 14:51, 23 April 2007 (UTC)[reply]


A perfluorocarbon contains carbon and fluorine only. A perfluorocarbon derivative may contain other atoms. The entry cutrrently says: "PFCs are made up of atoms of carbon, fluorine, and/or sulfur." which suggests a compound containing carbon and sulfur is a perfluorocarbon, which is clearly nonsense. And the image to the right is of a molecule containing hydrogen and oxygen.

I recommend a section on properties before Medicine, mentioning high gas solubility, low solubility with everything else, inert, biocompatible, high density. Then section on manufacture (perhaps with the history, connecting to Manhatten project). Later sections on applications can then build on that.

In the industrial section, mention the biggest source of CF4 in the atmosphere is aluminium production.

I will have a go at this myself if no one objects. F2Andy (talk) 12:13, 8 January 2008 (UTC)[reply]

usage in ransom cases

needs references 213.199.128.147 (talk) —Preceding comment was added at 14:51, 27 February 2008 (UTC)[reply]

usage in doping

i read somewhere it was used as a doping agent (in the 80s). can someone delineate, what that did/how it "helped" increase performance? —Preceding unsigned comment added by 84.129.163.77 (talk) 19:42, 31 July 2008 (UTC)[reply]

Definition of Perfluorocarbon

I think the definition of perfluorocarbons, and thus the page, should encompass not just fluoroalkanes, but also fluoroalkenes, and fluoroalkynes. This means that the whole article needs to be worked over. Right now it just focuses on fluoroalkanes, but what about perfluoroisobutylene??? Very toxic compound. Worth mentioning. Thanks. -Shootbamboo (talk) 17:19, 8 November 2008 (UTC)[reply]

There is a problem here that "perfluorocarbon" means different things to different people, and I an not sure there is a definitive answer. My take is that if hydrocarbons are compounds with only hydrogen and carbon (see http://www.google.com/search?hl=en&q=define%3Ahydrocarbon&btnG=Search), then logically a fluorocarbon should contain only fluorine and carbon, however, it is rarely used in such a restrictive manner. Thus, the "per" prefix is used to indicate that each hydrogen (in the corresponding hydrocarbon) has been replaced by fluorine (see here http://www.acdlabs.com/iupac/nomenclature/79/r79_734.htm).

Therefore, I would agree with shootbamboo; yes, I agree this page needs to discuss perfluoroalkenes and alkynes, or better still, rename this page to perfluoroalkanes, and have a new page for perfluorocarbons, with links to perfluoroalkanes page and a new perfluoroalenes page (and perhaps a perfluoroalkynes page, or just one perhaps unsaturated perfluorocarbons page). Chemicals, perfluoroalkanes are quite unlike perfluoroalkenes, and it does not make much sense lumping them together on one page.F2Andy (talk) 13:43, 11 March 2009 (UTC)[reply]

Neutrality and Factual Accuracy

This page mentions that perfluorocarbons are made of only carbon and fluorine, and then goes on to talk about how wonderful and non-toxic they are. Unfortunately, for the dignity of this article, perfluoroisobutylene is very toxic. This article is written in such a fashion that perfluorocarbons are the safest things ever, and conveniently omits facts on other toxic perfluorocarbons. -Shootbamboo (talk) 23:27, 11 November 2008 (UTC)[reply]

You are right; maybe the author was only thinking about perfluoroalkanes. --Itub (talk) 14:25, 12 November 2008 (UTC)[reply]

New article on medical applications?

per the consensus on violations of NPOV, I want to say that while some of this article has good content, it is dominant towards describing medical applications, along the lines of this webpage."Perfluorocarbon Emulsions" i think the intent of authors were probably chemists that overvalued the applications of perfluorocarbons to defend against editors who might be motivated by the global warming potential of perfluorocarbons. this "overvaluing of applications" (IMHO) led to a fundamentally flawed article (IMHO). i think the more chemistry based content like the fowler process should be at the fluorocarbon page. i might add it there, and seek to rename this page Medical Applications of Perfluorocarbons. -Shootbamboo (talk) 21:27, 23 November 2008 (UTC)[reply]

I reckon you could possibly fork of an article on that topic, but we need to keep the main article, and it is not yet so big it needs to be split. Just add in your extra content. Graeme Bartlett (talk) 04:03, 24 November 2008 (UTC)[reply]
i am raising issue with the name of the title itself. -Shootbamboo (talk) 04:24, 24 November 2008 (UTC)[reply]
I don't think the article is non-neutral; it is just incomplete and should be expanded. The previous authors presumably wrote only about the perfluorocarbons that they knew are actually useful, which is why the toxic perfluoroalkenes were neglected. But I don't see it as a conspiracy of the chemical industry. As for the global warming potential, it is already there, and in my opinion it is sometimes blown out of proportion. Yes, some perfluorocarbons absorb 10,000 times more IR light than CO2. But CO2 is found in the atmosphere in concentrations that are what, millions of times larger than the perfluorocarbons? Sure, let's avoid dumping them into the atmosphere when possible, but let's focus more on the CO2 which is already there in much more significant amounts. --Itub (talk) 10:32, 24 November 2008 (UTC)[reply]

Title dispute

What is the definition of a perfluorocarbon? -Shootbamboo (talk) 00:00, 25 November 2008 (UTC)[reply]

Health and Safety

I have removed this section, but want to explain why. Here is the original text:

"There is skepticism on the safety of PFC's regarding health. Some reports and studies testify of the links of PFC's in the human body and infertility."

This is referenced to here: www.naturalnews.com/025544.html [unreliable fringe source?]

From the cited article: "They took blood samples when the women were between four and 14 weeks into their pregnancies to check for concentrations of two kinds of PFCs -- perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS)."

So the article is not talking about perfluorocarbons at all, but other fluorochemicals. The two chemicals in the report already have Wiki entries (and the word "perfluorocarbon" appears on neither page): http://en.wikipedia.org/wiki/Perfluorooctanoate http://en.wikipedia.org/wiki/Perfluorooctane_sulfonate —Preceding unsigned comment added by F2Andy (talk • contribs) 13:48, 11 March 2009 (UTC)[reply]

Wrong reference

I don't know how to change the references, but in ref 28 there is a mistake, it is not "Aslam M, Khalil K" as two different persons but Mohammad Aslam Khan Khalil. Khalil being the familly name. —Preceding unsigned comment added by Akry39 (talk • contribs) 14:42, 9 June 2009 (UTC)[reply]

Really? Follow the link to PubMed, and they have them listed as two separate people, and you can click on either to see a separate lists of articles by either person.

Treatment of decompression sickness section

This edit added small section (Treatment of decompression sickness) with a dense load of sources to the article. The url's to the articles correspond to an organization affiliated with the person who added them, and the journals sound very specialized. -Shootbamboo (talk) 22:23, 16 November 2009 (UTC)[reply]