Talk:Polycarbonate

message: The chemistry section describes one (transterification synthesis) route (or a set of routes?). The synthesis section describes another process using phosgen. Which route is used for industrial production? If both routes are used, to what extent and for which purposes are the different paths used?  —Preceding unsigned comment added by 150.227.15.253 (talk) 13:47, 20 August 2010 (UTC)
thread_title:  Which synthesis route is used? 

message: The section Polycarbonate#Potential hazards in food contact applications gives as a source the web page http://www.greenhouse-coverings.usgr.com/polycarbonate.html. Unfortunately this source appears to be derived from Wikipedia(!), with many typos and misspellings added -- this external page is obviously not the original source, nor is it very credible. Please, would an expert look into this and either (a) find and credit the primary source, or (b) change the link to say "citation needed". -- 64.106.73.251 (talk) 00:01, 28 February 2009 (UTC)
replies: text: I think it's legit. If you look at the wayback of the weblink, the first time the page was saved was May 10, 2004 (link). Here's the diff of this page before May 10. Obviously the reference existed first. What it might mean is the website was copied, bad spelling and all. Wizard191 (talk) 01:58, 28 February 2009 (UTC)
replies: text: I've deleted the text - the "greenhouse-coverings" page is talking about polycarbonate resistance to cleaning products etc., not about food safety! Being resistant to a chemical is not the same thing as being food safe! 78.105.234.140 (talk) 16:17, 13 March 2009 (UTC)
thread_title:  Improper Source 

message: Lexan is similar to polymethyl methacrylate (Plexiglas/Lucite/Perspex) and is commonly described as acrylic in appearance, but is far more durable, often to the point of being described as "bulletproof", depending on the thickness of the sample and the type of weapon used. 
Lexan may leach bisphenol A, a chemical that some studies linked to cancer. These studies indicate exposure to low levels of BPA causes a range of serious health effects in laboratory animals.Potential hazards in food contact applications: see Polycarbonate for details An expert panel of 12 scientists has found that there is "some concern that exposure to the chemical bisphenol A in utero causes neural and behavioral effects," according to the draft report prepared by The National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction.  For the general adult population, the expert panel found a "negligible concern for adverse reproductive effects following exposures."http://cerhr.niehs.nih.gov/chemicals/bisphenol/draftBPA_MtgSumm080807.pdf
Comment:  In the  it states "In July 2014 the FDA stated that 
BPA in food contact applications is safe at the current levels occurring in foods." ~~~~kwilliam98 <ref Bisphenol A in Wikipedia>   
==Usage==
Lexan is used in the aerospace industry for aircraft canopies, windscreens and other windows, but can be found in household items, such as bottles, compact discs, and DVDs. Perhaps the most visible Lexan consumer products were the previous versions of the Apple iBook and iPod — their white plastic is Lexan. It also is used by Nalgene for their 1-liter wide mouth water bottle, popular with hikers and mountaineers. Lexan is also used by other water bottle manufacturers. 
Lexan is also used in:
* The visors for the helmets on the Apollo space program
* Automotive headlight covers to prevent small rocks and stones from breaking headlights bulbs
* Racing cars to replace heavier (and breakable) glass windshields and windows
* Greenhouses for covering
* The Flexdex skateboards "Clear" models
* Radio-controlled car bodies
* Motorcycle goggles and Visors
* Pseudo-brass knuckles
* Air hockey pucks
* Hockey rink glass
* Nike Bauer Supreme One90 and Supreme One70 ice hockey skates (specifically, the TUUK Lightspeed 2 blade holders)
* Some guitar picks
* An alternative for brass mouthpieces in brass musical instruments.
* All New York City Subway cars, from R110A to newer cars such as R160B feature Lexan as a defense against vandalism.<ref>http://www.nycsubway.org/cars/r110a.html NYCS R110A description
* The jars for Blendtec blenders
* Riot shields and the visors of Riot helmets
* The visor in some fencing masks, and in many industrial safety shields and masks
* Cosmic ray detectors as stacks of 1/4 mil sheets
* Doors for Pods in WWE Elimination Chamber
* A surfacing for features in terrain parks at ski and snowboard resorts
* Headstock coverings on certain acoustic guitars (Taylor Baby as an example)
* The electronics module/housing of the Synchronar digital watch is made from lexan
* Contact Lenses
* Rubik's Cube stickers
* As wall panels in machine guarding and paint booths for assembly lines
* Aerodynamic fairings for bicycles  — Preceding unsigned comment added by 86.161.241.158 (talk) 22:25, 9 November 2013 (UTC)
thread_title: Properties

message: * Lexan is often used in the TV show MythBusters to protect the show's hosts and crew from any explosions.
* Many of the clear containers used in the show Good Eats are Lexan containers.
</blockquote>
Anyone who wants to help figure out what of this should be added to this article please go ahead.Ccrrccrr (talk) 00:54, 22 July 2009 (UTC)
thread_title:  Lexan in popular culture 

message: I think this article should "spawn" an article about Bisphenol A polycarbonate. It even has its own CASNo: 25037-45-0 (http://www.commonchemistry.org/ChemicalDetail.aspx?ref=25037-45-0. Albmont (talk) 12:26, 30 December 2009 (UTC)
replies: text: It would be WP:UNDUE since that's the most common form of polycarbonate , maybe you should create an article about non-Bisphenol A polycarbonate.--Nutriveg (talk) 13:16, 30 December 2009 (UTC)
thread_title:  Separate article about Bisphenol A polycarbonate? 

message: This article claims that CR-39 is a polycarbonate that is used primarily in optics.  However, the article on CR-39 specifically states that CR-39 "should not be confused with polycarbonate".  Given that the chemical formulae are different and that PC is a thermoplastic while CR-39 is a thermoset, it seems that the apparent misconception that they are both the same should be removed from this article.  Any polymer or organic chemists care to confirm?   --Michael Daly (talk) 21:29, 16 June 2010 (UTC)
replies: text: You are right that CR-30 is not polycarbonate: . Wizard191 (talk) 12:24, 17 June 2010 (UTC)
thread_title:  Polycarbonate vs CR-39 

message: Why does a search for the term "Macrolon" redirect to this page when there's no mention of the term here at all?  —Preceding unsigned comment added by 84.160.142.106 (talk) 13:14, 16 December 2010 (UTC)
replies: text: Most-likely because its a misspelling of the trade name Makrolon. Wizard191 (talk) 15:31, 16 December 2010 (UTC)
thread_title:  Macrolon 

message: I believe it's incorrect to list coefficient of friction as a standalone mechanical property. Coefficient of friction is a measure of friction between two objects (the CoF article lists it as a "system property"). The only way I think a standalone value would make sense is if it's a polycarb-on-polycarb value (and it should be noted as such if that IS the case).  — Preceding unsigned comment added by 192.189.191.14 (talk) 15:21, 22 July 2011 (UTC)
thread_title:  Coefficient of Friction 

message: Hi, i having a problem that still not resolve up to today. I hope some one can help me. In my production line, i did use polycarbonate as filter body. The problem that i facing is, after assembly with two material (both is PC) with polyurethene (PU) sealing and leave inside oven with 75degree C for 3hours i found there is micro crack on the PC material. 
Hope some one can consult me. You can reach me at this email : tan@applemedicalplastics.com
Many thanks,
Ricky Tan  — Preceding unsigned comment added by 60.52.42.123 (talk) 14:49, 12 October 2011 (UTC)
thread_title:  Micro crack after assembly process. 

message: Hello, I would want the article to touch the following subjects: high temperatures and scratch resistance. I found out just a while ago that there are polycarbonate plastics called high temperature polycarbonate (a recent development?) that withstands higher temperatures. Therefore some information in the article about temperatures is incomplete, the melting temperature for example is somewhat a half-truth if there are polycarbonate plastics that do not melt at the temperature given in the article. Polycarbonate is soft as evidenced by easily scratched CDs and DVDs. In eyeglasses for example, polycarbonate lenses need a scratch-resistant coating to prevent surface scratches. Today's modern scratch-resistant coatings can make the surface of polycarbonate lenses nearly as hard as glass to protect against scratches.ref What are these coatings used in eyeglass lenses? --91.157.12.243 (talk) 13:51, 21 September 2012 (UTC)
replies: text: @91.157.12.243 For posterity, CR-39 used in eyeglass lenses is not actually polycarbonate, even though it's called that by most people. 75.108.252.146 (talk) 14:49, 8 January 2023 (UTC)
thread_title:  Specialty polycarbonate plastics 

message: Ram nareshji (talk) 10:09, 30 November 2012 (UTC)
thread_title:  Niche applications and comments 

message: I will be creating an environmental impacts section to the polycarbonate page for a class.
Dmccrimmon (talk) 02:48, 27 November 2014 (UTC)
replies: text: Sounds good.  Please be mindful of Wikipedian preference for WP:SECONDARY sources = reviews and books, not journal references.  And if you cite sources related to human health WP:MEDRS, an absolute requirement for such secondary sources. And  Wikipedia is not a vehicle for US information and US-focused impacts.  --Smokefoot (talk) 02:59, 27 November 2014 (UTC)
replies: text: That last is sort of a snarky comment and template, considering that the 3 biggest global producers of polycarbonate are Germany, Saudi Arabia, and southeast Asia.  SBHarris 04:38, 27 November 2014 (UTC)
replies: text: Well it was not intended to be snarky.  The content that this editor wrote was focused on US and referred to EPA as if it is universally authoritative and recognized.  Anyway, I thought that the content added by Dmccrimmon was such that we should include it incrementally, after discussions (sans snark).  Thanks for keeping us on our toes. --Smokefoot (talk) 14:45, 27 November 2014 (UTC)
thread_title:  Addition of environmental impacts section 

message: Polycarbonate can now be recycled and re-used to create a new type of polycarbonate known as BORG polycarbonateItalic text. It has comparable specifications and properties as the original product, but it is environmentally conscious - Borg polycarbonate  — Preceding unsigned comment added by Steves55 (talk • contribs) 11:24, 11 November 2017 (UTC)
replies: text: Wikipedia is not an advocacy group, so the fact that the material is "is environmentally conscious" is irrelevant to the project.--Smokefoot (talk) 14:40, 11 November 2017 (UTC)
thread_title:  Recycled Polycarbonate 

message: Many plastics can, but can polycarbonate be used for 3D printing ?   If so, this should be mentioned, and if not, why not ?   Would an expert please add this information ? Darkman101 (talk) 04:04, 14 October 2019 (UTC)
thread_title:  3D Printing ? 

message: The last sentence in the paragraph on its productions says: "The diphenyl carbonate was derived in part from carbon monoxide, this route being greener than the phosgene method." But in what respect is it greener? This sentences seems to imply dipehenyl carbonate is greener not just because it is less dangerous and toxic, but because it uses recycled carbon monoxide. But this ignores the fact that Phosgene is also produced from carbon monoxide. 2600:1700:38E0:A040:38C8:36E:659D:95BF (talk) 15:31, 3 November 2021 (UTC)
replies: text: Good catch.  I removed the sentence as it is dubious and not supported by the citation.Sandcherry (talk) 14:42, 4 November 2021 (UTC)
thread_title:  Erroneous implication in the introduction 

message: For some reason, a mention of films is there... despite it not really making sense in that section.
This oddity was introduced during a refactoring of the Applications section by @Smokefoot in edit 380413644 back in 2010, where it was moved from Niche applications.
Also, anyone know of a template to link to a specific, old edit.
--FavoritoHJS (talk) 00:23, 12 May 2023 (UTC)
thread_title:  A small oddity in Applications->Data Storage 

message: I don't have sources at hand for this but I'm an engineer and I know what things are made of so I will just say some stuff:
The section on mobile phones is kind of misleading. It's talking about it as though it was introduced recently and replaces glass phone backs, etc. This is bunk! PC was a very popular material for phones going back years and years; if I recall correctly BlackBerries (and many of the phones of that general type) had their frame made of some sort of ABS/PC alloy. Most cell phones prior to the smartphone age had plastic frames, and a lot of the times that plastic was polycarbonate. If you go back to the early 2000s/90s, that is when you start seeing more ABS. In general it went from ABS to PC to aluminum.
In general, the way polymers used for consumer products tend to work is like this: first they are exotic materials, "engineering polymers", used only in industrial and scientific applications, then in fancy high-end consumer equipment, then they become more commonly used for more things, and then they become commodity polymers. This is what happened with ABS between the 80s and 90s, and with polycarbonate between the 00s to now.
Anyway, someone should fix all these "applications" sections to better reflect what these polymers are used for and what they're good for. Lots of people will be designing good parts if we write our articles well! And lots of people will be designing shitty parts if we don't -- yecch. jp×g🗯️ 22:01, 28 November 2023 (UTC)
thread_title:  Applications