Talk:Silicone

I added a paragraph on "Silicon contamination of electrical switch contacts" I used inline citations as there are currently no footnotes and I am still learning how to properly edit articles (this is my first). Can someone please fix the references. Note that the two citations are available at: http://books.google.com/books?id=EkStW7v8VPkC&pg=PA819&lpg=PA819&dq=silicone+%22electrical+contacts%22+arc+forms+carbide&source=web&ots=FogO0hnUrp&sig=3nEWVOP0f7OcPjsWZqtJTr4tA8Q#PPA822,M1 and http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?tp=&arnumber=1135411&isnumber=25247 The contamination problem of electrical switch contacts is quite large, made so much worse by a popular misconception that silicone spray is a good thing to spray onto electrical devices. Thus making the public aware of the problem helps address it. It is not controversial, just not well understood by the public and most electrical engineers. Techguy95 (talk) 06:04, 30 November 2007 (UTC)

I do not agree with your explanation that Silicone has derived from ketone. What i think is that Silicone is based on the "Si" atom on the backbone added with the "one" form ketone structure.

Rgds, Alexandre Pereira - PORTUGAL

I agree with what you say. Like "silane", "silicone" is a modification of an earlier word in organic chemistry to reflect a basis in Si rather than C. The "one", like the "ane", is borrowed from the C based structure. Perhaps this can be worded more clearly in the article? I didn't mean to imply that the chemical itself was derived from a ketone, only the term.--Joel 22:29, 11 October 2005 (UTC)

Silicone in shampoo - how does it work and is it safe?

I'm seeing a lot of shampoos are usuing silicone to make hair manageable and shiny, how does it work and is it safe ? appearances 5/20/05

This is short-chain PDMS, very similar to synthetic motor oil. It's in a lot of pomades etc. as well. It's a "lighter" version of the silicone in aquarium cement and breast implants, the same way that progressively shorter chains of polyethylene become paraffin wax, then vaseline, then mineral oil. It makes hair manageable bacause it's slippery, and is better at this because it sticks to hair more strongly than mineral oil. It adds shine by smoothing out rough spots; it does this better because it has a higher index of refraction than most oils. Silicone oil is quite safe, unless you're injecting it, and even then it seems to be okay in moderate doses. Any method you could think of to harm yourself with the shampoo, the detergents etc. would probably be more harmful than the silicone. I'll work this material into the article eventually. --Joel 30 June 2005 16:06 (UTC)

Joel is right silicone oils are, as far as we know, completely safe. I've heard many indigetion medicines have silicone oils supposedly to line the effected area. I'll do a bit of research on this and see if it can be added to the article. Afn 12:57, 26 August 2005 (UTC)

Update: actually, the medication is simethicone, and it's used as an anti-foaming agent for gas sufferers. It has been added to the article.--Joel 22:31, 11 October 2005 (UTC)

The discussion of toxicity above and in the article seems overly reassuring. Chronic toxicity is rarely as well understood as is implied here. Highly unreactive compounds may have a demonstrably low acute toxicity. However, for any compound it is far more expensive and difficult to do experiments that even begin to reliably measure chronic toxicity, although two-year studies in rats usually involving about 50 animals per group typically satisfy regulators, even though such studies do not have the statistical power to find even a 1% effect. As an example of how the process of determining chronic toxicity can go awry, consider Teflon which is now being removed from the market because a compound used to make it (PFOA) is a likely carcinogen as judged by US EPA.

Some added references on toxicity (both acute and chronic) and links to proponents and opponents of the suitability of silicone compounds as food additives, breast implants and shampoo ingredients would be nice to allow readers to more easily make a decision for themselves.

An individual's decision is based not just on what is specifically known about a particular chemical or class of chemicals, but also on the reader's personal tolerance for chemical risk and confidence in the regulatory system to act with precaution and move quickly when initial toxicological estimates need to be revisited. Some quick Googling on the subject yielded this interesting controvery in Environmental Health Perspectives. --Brian Hill 07:25, 26 February 2006 (UTC)

The headline of that article is extremely misleading. Did you read the whole thing? "As for the acute toxicity effects reported by Lieberman et al. (1), many of the reported findings oppose the conventional wisdom of toxicology. Administration of up to 1 mL of a substance into the peritoneal cavity of a 25-30-g mouse (which is equivalent to 2.4 L injected into the abdominal cavity of a human) basically represents the maximum dose that can be administered to a mouse and far exceeds the dose of CSs that could be encountered by humans under any condition, including women with breast implants." If you can slog through the heavy technical stuff, the bottom line of the article is that the study was flawed and the biological pathway that cancer took in the mice doesn't exist in humans. Unless you have a chance of drowing in the stuff, silicone sounds ok. Anheyla 14:18, 6 August 2007 (UTC)

toothpaste cleans off silicone coatings?

I bought a mask for scuba diving and the guy said "clean the lenses with white toothpaste before you go in the water - it will remove any silicone "stuff" still on the lens which could make it fog up more than ever" I did as i was told and I had no trouble with the mask training in the pool this week, but then I did not try the mask before the toothpaste treatment. I think the mask is largly made of "silicone rubber".

What "silicone stuff" might have been on the lenses and why? What is in toothpaste that would remove it? And how does that work?

>>> Is the lens glass, plastic or rubber? Whatever, I suspect the toothpaste is used because it is mildly abrasive.--borborygmus 18:09, 2005 Jun 2 (UTC)

Thanks for reply - lenses are glass i think - and I am sure you are right, its because toothpaste is a mild abrasive. Tempting to think that there might be a more interestinf conclusion though! Soleil - UK

No problems

Advertising?

The last two items on the externals links section read like advertisments rather than bona fide info. Any strong objections to removal? MarcoTolo 01:06, 24 February 2006 (UTC)

Bakeware?

I'd like to see some mention of silicone bakeware (cake/muffin pans). Packaging I've seen claims that the FDA's approved it for oven use, but what about silicone as a cooking container in a microwave? It's listed as being microwave-safe, but have there been any external tests on this? -- Kala, 2006 April 23

Is there any data on the safety of silicone bakeware. I did a bit of research and found very little. What I did find said that silicone bakeware is chemically inert, and therefore quite safe, but the sources were not anything particularly reliable... Anyone? Porlob 14:24, 18 September 2006 (UTC)

Silicone is identical to siloxane

The two articles should be merged because they discuss identical materials with differint names.--Smokefoot 20:58, 24 June 2006 (UTC) Actually, I am beginning to think that they are not identical. Siloxanes have the formula R3Si-O-SiR3 or are similarly low MW.--Smokefoot 01:11, 25 June 2006 (UTC)

The two articles should be merged into one and the title should be changed to Polysiloxanes. Silicone is not a correct chemical term. It originates from the early days of silicon chemistry when a chemist named Kippling surmised that since silicon and carbon are neighbors on the periodic table they should form similar molecules. Kippling was aware of the formation of ketones by dehydrating hydrocarbon diols and believed he could form silicone by dehydrating silicone diols (R2Si(OH)2). However, when silicon diols are dehydrated they polymerize to form polysiloxanes rather than forming the double bond to oxygen. Kippling found his products had too high a molecular weight to be the expected silicone (R2-Si=O). Polysiloxanes became known as silicones outside of chemistry and are still referred to in this manner today. "Silicones" is often used to describe polysiloxanes (-[-R2Si-O-]n-; R=methyl, ethyl, phenyl, and trifluoropropyl) as well as silanes (R4Si). Silicone.chemist (talk) 03:54, 12 December 2007 (UTC)silicone.chemist

Silicones are polymers

This article, as it currently stands, is very inconsistant about dealing with the central fact that silicones are polymers. The second sentence includes "rubbery" as a "typical" property, but this applies only to silicone rubbers. It does not apply to liquid silicones (aka silicone oils), to solid, non-elastomeric silicones, or to bonded thin films of silicone. Another example of the confusion is in the Automotive section. It jumps from silicone greases to silicone rubber (the insulation on (some but certainly not all) ignition cables, to "silicones" that must be avoided in automotive body shops. The silicones that must be avoided in body shops are probably the liquid and grease forms. Silicone rubber is probably just fine in body shops.7802mark (talk) 18:04, 7 January 2008 (UTC)

Controversy

Some added references on toxicity (both acute and chronic) and links to proponents and opponents of the suitability of silicone compounds as food additives, breast implants and shampoo ingredients would be nice to allow readers to more easily make a decision for themselves....An individual's decision is based not just on what is specifically known about a particular chemical or class of chemicals, but also on the reader's personal tolerance for chemical risk and confidence in the regulatory system to act with precaution and move quickly when initial toxicological estimates need to be revisited. Some quick Googling on the subject yielded this interesting controvery in Environmental Health Perspectives.--Brian Hill 07:25, 26 February 2006 (UTC)

That is exactly why we do not need a statement from one person pushing a POV that breast implants, for example, have been 'cleared' as far as risks/dangers. This is not the case, as numerous article point out. IN fact, even the studies Oliver cites express the need for further study, particularly looking at what subsets of women might be more susceptible to adverse effects. Oliver has simply ignored all of this, and has gone all over Wikipedia spreading his POV. No it isn't science, when he selectively picks what supports his POV, and ignores all the controversy that still exists. He has called political an international (and Yale trained) expert epidemiologist on the subject , and completely dismissed the doctor's comments, deleting them whenever he can. This is not collaboration and it will not be tolerated as long as I and others who care about WIkipedia are here.MollyBloom 17:23, 29 June 2006 (UTC)

please refer to these links [1] [2] from the British health ministry summarizing the studies on this. These are their summations, not mineDroliver 17:53, 1 July 2006 (UTC)

Oliver's summations are distorted, as usual. IT is sufficient to have one article on breast implants with a reference to it. That article discusses all the issue.Gfwesq 14:00, 3 July 2006 (UTC)

This summary is verbatim from the UK equivalent of the FDA. If you find that distrorted, take it up with them. It is both relevent here as well as the BI articleDroliver 22:03, 22 July 2006 (UTC)

I agree with Gfwesq. The most recent studies show there is still a controversy. Also, neither the United States nor Canada have approved silicone implants for unrestricted use. Oliver also changed "consumer groups" to "class action lawsuit". Talk about political! Consumer groups were the first to begin raising the problems with silicone implants. This article already discusses the lawsuits, so to repeat it because YOU dont like them is ridiculous and inappropriate.jgwlaw 22:11, 22 July 2006 (UTC)

Double Bond to Oxygen

In the article, there is a recursive definition. If you look at the theoretical diagram of R(Si=O)R', it says it doesn't exist and apparently directs the reader to the text to find out why. The text then says it doesn't exist and directs the reader to the digram. No where does it explain why Si cannot actually double bond to O in the same way C does to form ketones.

    I was looking for this too.

• • I noticed this as well. =( Dept of Alchemy 20:38, 19 March 2007 (UTC)

How is silicone made?

Question not answered in text as far as I can see?

81.86.108.181 21:43, 14 December 2006 (UTC)

Silicon dioxide (beach sand) is reduced to silicon metal with the evolution of carbon dioxide. The silicon metal is powdered and reacted with methylene chloride and a copper catalyst in a fluidized bed reactor. The reaction primarily forms three silanes: trimethylchlorosilane, dimethyldichlorosilane, and methyltrichlorosilane. These silanes have different boiling points and are separated by fractional distillation. The dimethyldichlorosilane is reacted with water to form hydrochloric acid and dimethyldihydrosiloxane which condenses to octamethylcyclotetrasiloxane (D4). The cyclotetrasiloxane is opened by ring-opening polymerization and polymerized into longer linear molecules. The trimethylchlorosilane is used as a chain-stopper to control the molecular weight of the linear molecules. The polymer is purified by vacuum stripping off the remaining low molecular weight siloxanes.

Hope this answers your question.

Silicone.chemist (talk) 03:09, 12 December 2007 (UTC)silicone.chemist

Sex toys

If the article is going to have a list of applications and products, clearly sex toys belong there - this application has been around a lot longer than bakeware, which is relatively recent. --200.6.247.40 22:39, 2 January 2007 (UTC)

I agree

I agree 194.100.215.1 (talk) 12:06, 24 January 2008 (UTC)

I agree. Has someone added it before and someone else deleted it? I'm going to add it back; please watch this page so that people do not censor it. Cazort (talk) 02:39, 4 February 2008 (UTC)

Silicone for scar treatment - does it work?

There are very expensive silicone scar "sheets" that claim to used by burn centers and plastic surgeons. Has silicone been proven to improve the appearance of scars? yokyle 16:08, 9 June 2007 (UTC)

As I have suffered a car accident with the result of a burnt scar in my left leg, I have used the silicone patches. It's true that they are expensive and that they have to be used during a long period (6 months or more), but they did notably well the job -I still have the scar but it has significatively reduced, so for me it seems better than laser or surgery-. To reduce the cost, I cutted the original patch to the size actually required, and used it continued during 7-10 days with the aid of adhesive bands. The silicone seems to work creating an area where the skin is able to exfoliate the damaged epitelium as it receives oxygen, whithout the need to quick remplace it to face bacteriae (the last couldn't trapasse the silicone). For me, but is only a personal case and oppinion, they are useful. Andrés AO Barcelona Spain —Preceding unsigned comment added by 80.37.232.54 (talk) 13:10, 9 November 2007 (UTC)

Not to be confused with

I approve of the "not to be confused with silicon" part but I don't like the clarification beneath it that "silicones are rubbery and silicon is a strong element." It's an oversimplification, as not all silicones are rubbery and I don't really think the word "strong" is good classification for an element. I would rather see something like "Silicone is a compound and silicon is one of its elements" but if nobody comments then I will remove it altogether. - Pharaonic 20:51, 20 June 2007 (UTC)

I agree - the extra text is excessive. I decided to be bold and make the change. -- MarcoTolo 22:26, 20 June 2007 (UTC)

Injections?

Similar to breast implants, silicone has been used by transgender people who are unable to afford doctor-prescribed hormone therapy and/or surgery. I think this should be mentioned here. -- Miscellanium 16:44, 2 August 2007 (UTC)

Not only transgendered people, but also cisgendered women and men as well. Hormones are available on the street; silicone is used to further augment what hormones do and also to fill out the face, lips, etc. It is always used by those who can afford other fillers but want something permanent, silicone being the "best" filler (Restylane, Juvéderm, etc are not permanent). There's a saying; "The body ages but silicone never does". Charles 01:10, 30 October 2007 (UTC)

re use by cisgendered people: I hadn't heard of that. Why, I don't know...but it makes complete sense. Additionally, there are safety issues because silicone can shift in the body, so the "enhancements" no longer look ideal, and I believe that if one has too many injections, they can become toxic. I need to double-check that last bit, though. If nobody has any objections, though, I think I'll add this into the article. Miscellanium 17:40, 3 November 2007 (UTC)

It's obviously more prevalent in women, both transgendered and cisgendered, but men have it to augment pectoral muscles, to fill out hollow cheeks and to augment thin lips (but usually not to the extent a woman might). It's a filler of choice in that it is permanent and the risks are still being investigated as some think it was prematurely banned. The riskier uses are the applications where it is injected in very large quantities, such as to create breasts or to fill out thighs, hips and buttocks. The former is rarer these days with the price of breast augmentation going down but the latter two are still prevalent among those who are getting injections. The quality or grade of silicone is very important as well. The more marginalized groups, such as transgendered women, may find themselves getting injected with industrial grade silicone rather than medical grade, which is touted as being more safe. A friend of mine who is also a friend of a very famous transsexual woman from New York jokes that the down and out transsexuals of New York have enough silicone in them to lubricate the machines of all of industrial America. More often than not though, you'll find silicone in lips and cheeks than anywhere else. Charles 19:32, 3 November 2007 (UTC)

You're clearly more familiar with this topic than I am--maybe you should be the one to edit the article, unless there's another place more appropriate for this information that I'm not thinking of. Miscellanium 22:09, 3 November 2007 (UTC)

I have come across several sources regarding injections in the past and if I do find them again, I will surely augment the article (no pun intended) to include more information on injections. Charles 22:38, 3 November 2007 (UTC)

"Caulking"...

Silicone Caulk is actually not the correct technical term. The "caulking" industry now refers to such advance materials as "elastomeric sealants", with "caulk" being relagated to older lower performance materials. You can confirm this terminology change at the mfgrs sites for most of the sealants. Techguy95 (talk) 05:28, 30 November 2007 (UTC)

Caulking (verb) is the act of applying the product known as caulk (noun). So I changed it in the article. It's a big pet peeve of mine. —The preceding unsigned comment was added by 68.209.87.158 (talk) 03:41, August 22, 2007 (UTC)

"Glass joints made with silicone sealant can withstand hundreds of metric tons of pressure" - a metric ton is not a measurement of pressure, it's a measurement of mass or maybe force. Can this be qualified with an area such as yottagrams/attometer^2? 206.124.146.40 (talk) 02:21, 27 June 2008 (UTC)

Trade talk

I have manufactured the stuff before and I have contracted it in commercial, residential and industrial applications and I don't see the big fat hairy deal. The trade in construction is known as caulking. It is an unorganised profession with unsure union affiliations, because everybody does it even though caulkers are best at it and can make it look nice. But it's still caulking and you won't change that anytime soon. If it walks like a duck and it quacks like a duck, it's still a duck. You could call a toilet a "waste removal device" and the user a "sanitation engineer", but its still a toilet and what goes in it is pee and poop and it comes from your rear end. Some terms just stick - and so what? It's also fireproofing but that does not by any means mean that it's fireproof (as in immune to fire). If there's ever a building trades union called Sealanters or Sealers or something, then perhaps it's worth taking seriously but until then it's caulking, even though it's smarter technology today than 40 years ago. --Achim (talk) 23:00, 11 December 2007 (UTC)

Anonymous user edits

To identify the plethora of anonymous contributions, check http://wikiscanner.virgil.gr/f.php?pagetitle=Silicone

• Quite a trip. --Achim (talk) 23:00, 11 December 2007 (UTC)

Gobbledygook

I have revised to move technical data downward. Wikipedia is an encyclopedia, not a chemical manual, and what's needed first is a basic definition easy for nonscientists to understand, even if it's oversimplified. Lots of work still needed on this article, though; I note that several uses mentioned above are not yet included.75.57.139.67 (talk) 21:48, 27 December 2007 (UTC)

Silicone rubber merge

Whoever suggested this merge hasn't commented on it here, but the amount of detail in the current silicone rubber article is too much too be included here, and the discussion above implies that the science types would be outraged by less. Better to add a "Forms of silicone" section here and and link to it.75.57.139.67 (talk) 22:24, 27 December 2007 (UTC)

I just added the merge tag to the silicone rubber page, which the originator did not. I think both articles could use a general overhaul, possibly along the guidelines above, but, really, both pieces contain too much detail. There's room to cut loads of minutia, in which case they could be condensed into a single piece. Contributors need to be reminded that encyclopedia articles need not, themselves, be encyclopedic in scope. Fijagdh (talk) 17:49, 4 April 2008 (UTC)

I agree to the merge. —Preceding unsigned comment added by 201.255.144.247 (talk) 00:10, 13 May 2008 (UTC)

History?

I was looking for who invented the stuff or how it was discovered. I don't know but someone who does could add. —Preceding unsigned comment added by Lkleinow (talk • contribs) 15:14, 2 April 2008 (UTC)

Merge proposal

I am against the proposed merger because there is enough information to make this a separate article. It is a material which is well represented among elastomers and quite distinct fro oligomeric silicones. Peterlewis (talk) 09:04, 2 May 2008 (UTC)

http://en.wikipedia.org/w/index.php?title=Talk:Silicone/Comments&action=edit

Please keep the user in mind. Throwing everything into a silicone page would be unwieldly thus unuseable, surely not Wikipedia's purpose. I recommend separate pages for specific types of silicone and/or applications that are common or otherwise important.

For example, "silicone rubber" is a common application. Topics for the page might include: - what molecular aspect is common to flexible compounds (type of atoms, bonds, whatever is the essence.). - essentials of properties - common terms of importance, such as addition-cure versus condensation cure of two-part compounds and the various common types of one-part - essentials of fabrication (heat-cure, injection molding, two-part, release cure or whatever you call the common process of curing of one-part, etc.)

An example of an essential is that commonly available one-part RTV compounds need water vapour in the air to cure. Very important if the user is in a high desert location (where both warmth and moisture are inherently lacking).

Along the way there are detail choices to be made. That is life. For example, safety of silicone compounds will be covered in both the generic silicone sections and very specific subjects such as the breast-implant page of Wikipedia (silicones being one type of material used for those). Examples of safety aspects for generic silicone rubber are its general inertness once fully cured, that condensation cure compounds often cause skin reactions, that one-part compounds release vapours, and that prolonged intimate contact requires higher standards such as USPS Class VI or VII. —Preceding unsigned comment added by RationalKeith (talk • contribs) 18:37, 16 May 2008 (UTC)