Talk:Polystyrene

Table of data: remove items?
The term polystyrene encompasses a large family of products, with widely different properties. However, the table of data at the beginning of the article seems to give a precise description of only one particular example of polystyrene, probably some GPPS grade.

For example, "elongation at break" is reported to be only 3 - 4% (typical of fragile products like GPPS) whereas many HIPS grades show values as high as 60%.

Similarly, Vicat depends directly on how much white oil is added to the polystyrene and may range from 80 to almost 100ºC. The 90ºC shown in the table is just one of the many possible values.

I propose to remove the items of these table that differ among polystyrene types. Is anybody against? - Hispalois 09:52, 21 May 2006 (UTC)


 * Agree. Properties listed against class should span full range, or else identify as pertaining to subset only, in which case identify subset.
 * DIV (128.250.80.15 (talk) 04:18, 23 December 2007 (UTC))
 * Well its a year later and no one has fixed it. Maybe if I find time I'll try and clean it up. --Wizard191 (talk) 14:03, 21 September 2008 (UTC)

I think removing the table would be an error, infact given its currently half down the page, i actually thing it should be bumped higher up the page. However clearly it does need to be started that this is an example of a performance of a non-foamed general purpose PS rather than a cover-all for any polymer containing PS! If you removed all the data that can vary between different PS types you would have an empty table Perhaps a second table could be added containing similar data for expanded or foamed PS? See also my comments about ABS/SBR comments. dhutch 18:16, 3 January 2010 (UTC) Preceding unsigned comment added by Dhutch (talk  contribs)

I would prefer to keep the data but qualify it according to PS type. Will Mengarini (talk) 00:08, 21 December 2017 (UTC)

Inclusion of HIPS
I realised as always its a case of 'where do you draw the line' however is there any real reason why both ABS and SBR have there own page while HIPS does not? dhutch (talk) 18:29, 3 January 2010 (UTC)

Burning/Melting
Does anyone have information on the health/environmental effects of burning/melting polystyrene in a fire, and if disposing of it in that way is environmentally acceptable? 68.230.161.164 (talk) 04:49, 22 January 2008 (UTC)

Fahrenheit
If polystyrene's melting point is 100 degrees C., then the main article could be improved by giving its equivalent in Fahrenheit. Can this temperature be sourced somewhere? 216.99.219.234 (talk) 06:40, 22 September 2011 (UTC)

Unclear sentance
This sentance is unclear and could use some clarification. "In the United States, environmental protection regulations prohibit the use of solvents on polystyrene (which would dissolve the polystyrene and de-foam most of foams anyway)." —Preceding unsigned comment added by 71.100.28.83 (talk) 23:17, 7 November 2008 (UTC)

Possible Bogus Reference ([6], "behind aluminum")
I noticed a problem with the section citing reference [6], in the "Environmental concerns and bans" section. Namely, the report cited simply alludes to another report which, in turn, does not properly reference a source that can be verified. Here's the lifted text: 'Despite these commendable improvements, the CIWMB Report finds that “in the categories of energy consumption, greenhouse gas effect, and total environmental effect, EPS’s environmental impacts were second highest, behind aluminum.” The CIWMB Report continues with the recommendation that because there is little, if any, likely avenue of further source reduction, single-use products that cannot be effectively recycled should be replaced with recyclable or compostable materials.' This is troubling because the claim that aluminium is even worse than styrofoam is controversial, at least where common-sense knowledge is concerned. Aluminium is easily recycled and, as far as I know, even earns revenue for recycling programs as valuable scrap. What should we do to fix this dubious claim? I have no idea what to do about a bogus citation. --InformationalAnarchist (talk) 17:36, 26 January 2008 (UTC)


 * I just deleted the whole, dubious claim (and its dubious reference, too). --InformationalAnarchist (talk) 19:46, 2 July 2008 (UTC)
 * There is no reason to disbelieve this statement which is about lifecycle effect, not recycling profits as IA seems to think. I would have returned it except I could find no high quality source - Google just found a couple of wiki clones and a couple of blog type entries. Rmhermen (talk) 00:09, 5 January 2009 (UTC)
 * Yes, and I mentioned the scrap value as a side-benefit. I should have made that more clear. What I mean is that it is very bad news indeed if such a highly recyclable material has such a high environmental impact. I had been advising people that aluminum is better, recycle-wise, than plastic (but that re-use always trumps recycling), so I was really dismayed that my advice might have been causing more harm than good. That's why I went looking for a source to verify the statement.
 * On a side-note, "there is no reason to disbelieve" may be true, but there is no reason to believe, either, without some evidence. If you have it, I would definitely like to see it (and I mean that sincerely). --InformationalAnarchist (talk) 01:51, 16 June 2009 (UTC)

What, if any, is the difference?
Peter Horn 00:57, 14 February 2008 (UTC)
 * polystyrene
 * polysterene


 * "Polysterene" is almost certainly just an incorrect spelling of polystyrene. There are molecules called sterenes, but they are dehydrated versions of sterols, and not used as monomers for polymer formation. I will delete the references to polysterene unless some one can provide a real reference (not misspelled) for polysterene. Silverchemist (talk) 21:08, 14 February 2008 (UTC)

"Styrofoam" Peanuts
Regarding the following edits: Just because foam peanuts were originally made by Dow Chemical does not mean they are made out of "styrofoam" (tm). Styrofoam, still made by Dow Chemical, is typically blue and it is put on the sides of houses for insulation purposed. It should not be confused with generic foam products such as cups of peanuts. If the article states peanuts are made of "styrofoam" then a credible reference should be provided. For more information about Styrofoam see: Dow's WebsitePlhofmei (talk) 04:51, 22 September 2008 (UTC)
 * 00:44, 22 September 2008 (hist) (diff) Polystyrene ‎ (Undid revision 239842733 by Wizard191 (talk) -- See talk page) (top)
 * 15:41, 20 September 2008 Wizard191 (Talk | contribs) (23,991 bytes) (→Extruded polystyrene foam: rmv fact temp because the packing peanut article states that they were originally made by dow) (undo)
 * 14:19, 20 September 2008 (hist) (diff) m Polystyrene ‎ (→Extruded polystyrene foam: - COrrecting previous edit.)
 * 14:18, 20 September 2008 (hist) (diff) Polystyrene ‎ (→Extruded polystyrene foam: - Reference for Foam peanuts being made out of "Styrofoam" needed. "Styrofoam" is a special form of polystyrene trademarked by the Dow Chemical Company.)


 * Upon rereading the section, I think your point is moot. The way the section reads is as follows:

Extruded polystyrene foam
Extruded polystyrene foam (XPS), which is different from EPS, is commonly known by the trade name Styrofoam. The voids filled with trapped air give it moderate flexibility, a low density, and a low thermal conductivity. Familiar uses include packing "peanuts" and molded packing material for cushioning fragile items inside boxes[citation needed].


 * The whole section is about XPS, not styrofoam. It just notes in the first sentence that XPS is often referred to as styrofoam (mistakenly or not). Therefore the sentence in dispute is actually just saying that packing peanuts are an example of a use of XPS. --Wizard191 (talk) 13:10, 22 September 2008 (UTC)
 * Yes, it can read that way, The entire section probably could use a reword, "Styrofoam" is a specific kind of XPS.  Dow Chemical still actively uses and protects their Styrofoam trademark.  Perhaps the first sentence should be completely whacked or at least the part "is commonly known by the trade name Styrofoam"?Plhofmei (talk) 16:04, 22 September 2008 (UTC)


 * Perhaps it can be reworded slightly to not confuse readers that they are interchangeable, however, I think that it needs to be noted that XPS is often called styrofoam (usually incorrectly). --Wizard191 (talk) 19:12, 22 September 2008 (UTC)
 * I concede the point that the trademark has come into some generic use, but Dow Chemical still actively uses the name and has education campaigns about the Trademark (at least they did 5 years ago). I'll work on a rewording.Plhofmei (talk) 23:31, 22 September 2008 (UTC)


 * I'm glad that we are working on reaching a compromise here. However, I do think that first sentence of the section should note the styrofoam name, just because it is such a commonly used term. Here's my attempt:


 * "Extruded polystyrene foam (XPS), which is often incorrectly called by the trademarked name Styrofoam, has air inclusions which gives it moderate flexibility, a low density, and a low thermal conductivity."


 * BTW, the "TM" symbol shouldn't be used per WP:Trademarks. --Wizard191 (talk) 02:32, 23 September 2008 (UTC)
 * Agreed on the edit. Thank you for the policy note.  Chalk up another edit war avoided, EWO-man. ;) Plhofmei (talk) 11:56, 23 September 2008 (UTC)

Consumption of polystyrene by animals
We keep chickens and geese and they seem to find polystyrene foam pretty tasty. Since we eat their eggs, should we be concerned about this unusual dietary component? Is it harmful to the animals? You'd think it would be easy to stop them eating it but we have quite a bit of it around for propagating plants, etc. 121.218.62.245 (talk) 12:42, 3 November 2008 (UTC)

Clean Air Act - citation?
The statement:
 * "By January 1994 use of all chlorofluorocarbons (CFCs) for foodservice polystyrene foam was prohibited per the Clean Air Act."

Is tagged as needing a citation. Why is that? It links to the Clean Air Act, which does indeed address CFCs. If nothing else, it should just be clarified that the Act is limited to the US. What possible citation is there? A direct link to the Act - like on the very page it's linked to? --208.97.121.178 (talk) 20:10, 25 September 2009 (UTC)


 * I've removed the statement because it is partially dubious. The exact text is:
 * Effective January 1, 1994, it shall be unlawful for any person to sell or distribute, or offer for sale or distribution-- (1) any aerosol product or other pressurized dispenser (other than a medical devise or diagnostic product, including drugs, as defined in the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 321) or a drug delivery system) which contains a substance listed under subsection (b) of section 504; or (2) any plastic foam product (other than a foam insulation product) which contains or is manufactured with a substance listed under subsection (b) of section 504.


 * As you can see it's not just for polystyrene nor just foodstuffs; its for any "foam" product other than insulation. If someone finds this interesting enough to add to Wikipedia please don't add it back here; perhaps in the Clean Air Act (1990) article. Wizard191 (talk) 00:39, 26 September 2009 (UTC)

Claim without Citation
I have removed the statement:

"According to the California Coastal Commission, it is now a principal component of marine debris."

until it can be backed up with a valid citation. —Preceding unsigned comment added by User7984 (talk • contribs) 10:14, 6 November 2009 (UTC)

Common name
How do you call this in everyday life? is it the same for Americans and for the British?--camr nag 19:49, 6 November 2009 (UTC)


 * As far as I know in the UK its mainly called polystyrene or expanded polystyrene. Or in engineering/materials/polymer circles often abbreviated to PS (along with HIPS, ABS, PP, HDPE, etc) dhutch 18:20, 3 January 2010 (UTC)


 * Same goes for American usage as well. Wizard191 (talk) 04:14, 4 January 2010 (UTC)


 * Of course, it is often not differentiated, just "plastic", a much broader term including several other materials. Gene Nygaard (talk) 04:32, 4 January 2010 (UTC)
 * And, of course, in the opposite direction of specificity for the expanded stuff, the brand name Styrofoam gets generalized even if the owners of the trademark like to pretend otherwise. Gene Nygaard (talk) 04:36, 4 January 2010 (UTC)

Consumer awareness
The article said "Currently, the majority of polystyrene products are not recycled because of a lack of consumer awareness regarding suitable recycling facilities and collection methods." This claim is far too strong and probably not true. One thing is that there is not very much to be aware of. Many plastics can be recycled, but in most parts of the world there is not much a consumer can do to help it. Even if every consumer had that opportunity, many of them wouldn't do it anyway. Not because of not being "aware", but just not feeling like it. Please feel free to put back the awareness part if you can find a reliable source (which is NOT an organisation heavily subsidized for "raising awareness"). Joepnl (talk) 20:10, 27 November 2009 (UTC)

Costing and Calculation
There is a need for sub-section wherein an Expert can share how do you commercially calculate the cost of Thermocol, what is the formula. For example: If a person 'Y' needs to buy cut pieces of rectangular thermocol with L-2in, B-1in, H-6in (100 pieces) how should he/ she calculate the rate?

59.184.18.105 (talk) 07:39, 13 April 2010 (UTC)Best regards, Ypschita


 * Unfortunately that's scope creep for Wikipedia. See WP:NOTHOWTO for more information. Wizard191 (talk) 12:37, 13 April 2010 (UTC)

Unclear
I was looking for information on the common housing material known as foil-backed polystyrene. At what temperature does it ignite? I went to my local Home Depot outlet, and recognized what I wanted:  foil-backed polystyrene. Styrofoam is a lot less expensive, and a lot easier to ignite. But foil-backed polystyrene looks like it is a lot safer, inasmuch as it is a big block of fiberglass wool that has been dipped in a bath of foamy polystyrene prior to being squeezed (rather loosely) between two sheets of aluminum foil.

Somewhere in Wikipedia there should be an article on foil-backed polystyrene. But I don't know where to find it. Can anybody help? Dexter Nextnumber (talk) 03:53, 5 May 2010 (UTC)


 * Foil-backed polystyrene would probably be found here, but I don't think there is any info about it in the article. Note that the ignition temperature it going to be dependent to each manufacturer, so I don't think you'd ever find it in a Wikipedia article. Wizard191 (talk) 12:26, 5 May 2010 (UTC)

This should be included in the recycling section.
http://ourworld.unu.edu/en/plastic-to-oil-fantastic/ —Preceding unsigned comment added by 98.238.129.133 (talk) 20:04, 25 August 2010 (UTC)


 * For those who are curious, this seems to be a small-scale application of the well-known process of thermal depolymerization. So I'd caution against getting too wild about it. --Wascally wabbit (talk) 04:43, 9 June 2011 (UTC)

'Plastic Padding'
In the UK there is a product range called 'Plastic Padding' produced by Henkel Loctite Adhesives Ltd. I have bought 'Chemical Metal' and 'Leak Fix' (which appear identical). It consists of two tubes of chemicals which you mix together to produce a thick paste which sets rock hard in 10 minutes. It is meant to seal or repair metal, stone, wood, china and glass, and can be sanded, machined, drilled, tapped and polished, and is resistant to water, oil, petrol, weak acids, and temperatures up to 160 celsius. It is widely sold in car (automobile) accessory shops for repairing car parts (including cracked cylinder blocks!). Nowhere in the documentation does it explain what exactly it is, but examination of the small print regulatory information reveals that its two components contain styrene monomer and dibenzoyl peroxide. It is therefore merely a way of making polystyrene.

109.144.253.112 (talk) 21:09, 27 October 2010 (UTC)

Biased tone of article
Large sections of the article are written in a non-neutral tone to diminish or downplay the environmental, health-related and other criticisms of the product. Much of the article reads as thought it is a response to or defence against such criticisms. —Preceding unsigned comment added by 86.177.108.81 (talk) 23:54, 26 April 2011 (UTC)


 * I concur. These sections in particular were noteworthy:


 * "When it is not used to make more EPS, foam scrap can be turned into clothes hangers, park benches, flower pots, toys, rulers, stapler bodies, seedling containers, picture frames, and architectural molding from recycled PS."


 * and


 * "Foam cups and other polystyrene products can be safely buried in landfills, since it is as stable as concrete or brick."


 * and this, which does not explain that it's getting to styrene from polystyrene that is the concern:


 * "Furthermore, styrene is quickly broken down in the air, evaporates quickly in shallow soil and water, and what remains in soil and water can be further broken down by bacteria and microorganisms."


 * --Wascally wabbit (talk) 04:32, 9 June 2011 (UTC)

Biased tone, evidence of styrene from polystyrene?
"Polystyrene foam is a major component of plastic debris in the ocean, where it becomes toxic to marine life. Foamed polystyrene blows in the wind and floats on water, and is abundant in the outdoor environment. Weathering by wind, sun, rain, and wave action degrade polystyrene to known and suspected carcinogens, including styrene monomer (SM), styrene dimer (SD) and styrene trimer (ST).  However, styrene is an organic, naturally occurring substance [balony: not in any substantial amounts] in our environment and to date, no regulatory body anywhere in the world has classified styrene as a known human carcinogen...." The above is semi-alarming given the likely amount of polystyrene in the environment, but we need to be truthful/factual in our reporting. Where are the publications showing degradation, esp large scale degradation of styrene polymers into the monomer? I see a minor Japanese group gave a lecture at an American Chemical Society meeting (these meetings accept all lectures and cannot be considered as any form of validation), and I see that the US magazine National Geographic says something about the same theme. National Geographic is hardly a technical source (no protocols provided, no refereeing, newsy-glitzy (but nice!)) but tends to report on reports. So is there any substantial literature on reversion of polystyrene to styrne. That depolymerization is hugely "uphill". My suspicision is that the literature is very thin and mainly reports about other reports. And the content in this section is driven by environmentally concerned editors who lack the sources. Not that I think pollution by polystyrene is a good thing...--Smokefoot (talk) 14:14, 11 June 2011 (UTC)


 * I decided to search for more by the researcher (Katsuhiko Saido) mentioned in the Science Daily article. I found this web site, which lists a number of his publications (all of them?).  I lack the expertise to understand or criticize them, however.  I also lack the background in the subject to judge how well-received the idea is among the scientific community.  There doesn't seem to be much reference to it in a Google Scholar search, though.  --Wascally wabbit (talk) 17:18, 17 June 2011 (UTC)

Glue / Bond from EPS
RECENTLY THERE WAS AN OPINION CAME UP THAT THE EPS CAN BE RECYCLED TO PRODUCE BONDING MATERIALS WHICH IS AS GOOD AS PATTEX & CAN BE USED IN WOOD ETC., NEED CITATION AND AUTHENTIC VERSION. THANKS. — Preceding unsigned comment added by 117.202.115.229 (talk) 09:20, 12 January 2012 (UTC)

Thermal resistivity and conductivity
There is something slightly wrong in the sections "Expanded polystyrene" and "Extruded polystyrene foam". The values given for the thermal resistivity and conductivity should be exactly each other's reciprocal, but they aren't, except very roughly, with errors up to about 40%. No source is given for any of those numbers and I'm unable to guess which of them is verifiable, if any. Judging form what sources generally say, I'm more inclined to distrust the resistivity values of 36 m·K/W and 35 m·K/W given in those sections. These values should be lower, around 30 m·K/W. — Adi  Japan  06:17, 23 August 2012 (UTC)

Biodegradable
Added references to biodegradation of polystyrene. — Preceding unsigned comment added by GGIwin (talk • contribs) 14:23, 5 November 2012 (UTC)
 * Would someone add that polystyrene can be digested by mealworms? Wcbpolish (talk) 13:32, 4 February 2016 (UTC)
 * , done. SageRad (talk) 14:07, 4 February 2016 (UTC)
 * Earlier I was hearing a strange chewing sound and I spotted an American cockroach munching on the edge of a small EPS tray. The tray is quite clean and it is clear from the missing bit that it was eating the material itself. A forum notes how cockroaches of another species eat it, too. I don't know how much they digest it, but it shows that not only mealworms eat this stuff! Who is like God? (talk) 01:25, 16 April 2018 (UTC)

What about the section Non-biodegradable? --Leyo 10:32, 7 March 2016 (UTC) PS. There is also a second part of the above study: 10.1021/acs.est.5b02663.

Incomplete reference
The ´Haynes` reference is not completely described - does anybody know what this is? — Preceding unsigned comment added by 129.129.113.82 (talk) 09:23, 28 November 2012 (UTC)

Entanglement - Misrepresented Reference
I've partially reverted the edit made by 108.7.171.137 on 20:30, 3 January 2013, citing the following:



It is a news story about how a bird used man-made materials (without harm)in building its nest. Although it does mention "Styrofoam", and mentions the perceived potential for entanglement from the items that the bird used (mentioning fishing line, rope, and electrician's tape), it is difficult to see how a lump of "Styrofoam" could cause entanglement. In fact, expanded polystyrene is quoted by some sources (e.g., ) as a suggested nesting material.

Its use in supporting the claim that expanded polystyrene is an entanglement hazard is adding emphasis that is not present in the source, and so is and misrepresenting the source.

Interestingly, the article mentions that the bird (an osprey) had also used a bicycle pedal (complete with reflectors) as part of the nest. I don't expect anyone to suggest that we ban bicycles to protect wildlife...86.7.23.116 (talk) 13:43, 11 January 2013 (UTC)

Maybe the different kinds of PS needs to be split into separate articles
The current article covers a family of related but very different materials, resulting in much confusion and vagueness as to which statements apply to which material. Especially in the impressions on lay people without prior knowledge of these things, dangerous misunderstandings are likely to result, as can even be seen in some other comments on this page.

I would like to suggest that the article is split into multiple inter-linked articles on the different Polystyrene-derived materials. Suggested article titles (some of them currently redirects) would be Solid Polystyrene, Polystyrene foam (the kind that is directly blown or sprayed), Expanded Polystyrene (EPS, the kind made by fusing gas-filled beads), Extruded Polystyrene (XPS) and High Impact Polystyrene (HIPS, the kind that has an elastic polymer mixed in for strength).

It would take expert assistance to correctly untangle the various statements in the current article as to which of the split articles they should go into (some will obviously need to appear in more than one, some not).

(Sorry, not logged in at this computer)2001:16D8:DD73:F0:250:56FF:FE00:5A (talk) 21:02, 26 April 2013 (UTC)
 * Great idea but we have few editors who know sufficient about these classes of PS. I would be glad to help but a real expert would need to lead the effort.--Smokefoot (talk) 00:23, 27 April 2013 (UTC)

Paintability of expanded polystyrene
I'd just like to know if "beadboard" (as used in this Article) can be successfully painted with anything. Perhaps other searchers would like to know this, too, as this material is readily available in 4' x 8' sheets and as various sized beams to hobbyists and home owners in American home improvement centers. Perhaps including this information seems far-fetched, but I feel it's important to always keep the most likely reasons why people do searches in mind. Mykstor (talk) 19:13, 26 May 2013 (UTC)

Melting / Softening
I thought polystyrene was an amorphous polymer? If it has no crystal structure it cannot 'melt' and therefore has no melting point. It does flow like a liquid above its Tg but a melt and a glass transition arr two different physical processes. Any objection to me altering this article? Phil the (talk) 10:59, 10 June 2014 (UTC)
 * If you are an expert polymer engineer or chemist, add content, otherwise dont. Depending on the tacticity and MW, the melting temp of PS varies.  --Smokefoot (talk) 12:38, 10 June 2014 (UTC)

Possible ref
http://m.huffpost.com/us/entry/6439410  Bananasoldier  (talk) 07:57, 10 January 2015 (UTC)

Adhesive / Cement
Please would someone knowledgeable add information on exactly what solvent is used as an adhesive or cement for polystyrene ? (The article only generalises on "organic solvents") Many thanks ! Darkman101 (talk) 23:56, 25 August 2015 (UTC)
 * For polystyrene (compared to acrylic or ABS) a great many solvents can be used. Methyl ethyl ketone is one widely used amongst modellers. Most commercial solvent glues are mixtures though. Andy Dingley (talk) 00:32, 26 August 2015 (UTC)

Review articles
Some more recent review articles would be useful: These are a few i found with PubMed that could be useful for updating this article. SageRad (talk) 16:03, 7 January 2016 (UTC)
 * Modeling the effect of nano-sized polymer particles on the properties of lipid membranes.
 * Value of phagocyte function screening for immunotoxicity of nanoparticles in vivo. (Free)
 * Green polymer chemistry: enzyme catalysis for polymer functionalization. (Free)
 * Current trends in using polymer coated gold nanoparticles for cancer therapy.
 * Functionalized polystyrene nanoparticles as a platform for studying bio-nano interactions. (Free)
 * In vitro and in vivo interactions of selected nanoparticles with rodent serum proteins and their consequences in biokinetics. (Free)
 * PS is a huge topic, and relative to the real world themes of interest to readers, these reviews seem narrowly focused. Would be a good starting point for an article in a technical journal though. --Smokefoot (talk) 19:12, 7 January 2016 (UTC)
 * Well I bet some readers are interested in more up to date research on health effects and uses. And nano particles have received lots of coverage lately.  Wikipedia is great in that it can help readers to access research by work of editors like us. SageRad (talk) 19:15, 7 January 2016 (UTC)
 * Well if readers are interested in up to date research, they should go somewhere else because Wikipedia is not a news source, per WP:NOTNEWS. If one wants reviews on PS, 50 appeared in 2015. Prior to that 3547 reviews appeared, summarizing 256,342 reports.  Data from Chemical Abstracts from today.   --Smokefoot (talk) 23:04, 7 January 2016 (UTC)

Rastra - Trade name for ICF
The inclusion of "Rastra" in the page appears to be for commercial (advertising) purpose. — Preceding unsigned comment added by 192.243.88.182 (talk) 23:35, 8 March 2016 (UTC)

depron
I search on depron and end up redirected here and there is no reference anywhere in the article to depron. I suspect that there was one but someone removed it. Why can't we just have an article on each thing so people can look things up without a battle through a bunch of stuff they don't want only to find out it isn't even included? — Preceding unsigned comment added by 71.212.23.127 (talk) 22:26, 20 September 2016 (UTC)
 * Wikipedia is written by volunteers. We have difficulty attracting contributors who are expert in the polymer area, as well as many other technical topics.  That's just the way it is.--Smokefoot (talk) 00:34, 21 September 2016 (UTC)

IP edit which changed the words and meaning of a direct quote
Hi! This edit was made two years ago by an anonymous IP editor. In it, the editor changed the words and meaning of a direct quote, and made some other changes. What are your thoughts regarding the edit? Kind regards, —Unforgettableid (talk) 15:19, 17 June 2020 (UTC)
 * Four years ago, not two! Good job spotting this. Direct quotes should be fixed immediately. The changes outside quotes are less concerning (they verge on POV but are relatively minor). Wikiacc (¶) 18:07, 17 June 2020 (UTC)
 * Fixed. The first quote just needed to be restored (though I'm a bit concerned the source is not impartial). The second quote wasn't a quote at all, but a paraphrase of the lay summary of the paper. Wikiacc (¶) 18:15, 17 June 2020 (UTC)

Density of Styrofoam shown is wrong
Shown at 1 gram per Cc This would imply same Wright as water 70.67.169.225 (talk) 16:31, 27 January 2022 (UTC)
 * That's for solid polystyrene, the foam is a lot lighter (0.01-0.04 g/cm3). --Project Osprey (talk) 20:29, 27 January 2022 (UTC)

Citation for Safety study cannot be verified
The safety section refers to the Harvard Center for Risk Assessment. Is this a separate organization to the Harvard Center for Risk Analysis? More importantly, the citation 108 for "Harvard Center for Risk Assessment" is for an article by The McLaughlin Centre for Population Health Risk Assessment, with no mention of Harvard University. Beep4BoingEE1 (talk) 04:00, 22 March 2023 (UTC)