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I see a red word and I want to paint it black

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Lots of red wording going on. Fairly ambitious to expect every one of those to be linked to given the specialism of the materials involved. Maybe just untag them? As whoever added them is probably one of the only people who knows what they are to an extent that he can write about them.

I suspect a large chunk of this article has been written by a chemist who works with these.

I'm all for the detail and passion, but darn! Even I, as someone who spends most of his free time and money buying chemistry gear and playing around in the garage, am struggling with the none broken blocks of tongue twisters. This is a prime example of where Pedia could learn from Encyclopedia Dramatica, and add compressed sections on the details that can then be expanded by people after the specifics.

Besides, not enough mention of paint for my liking. :D —Preceding unsigned comment added by 82.24.47.178 (talk) 19:21, 19 October 2010 (UTC)[reply]

Carpet underlayment

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165.139.171.10 edited this page by adding the "carpet underlayment" bit. 165.139.171.10 21:27, 6 February 2004 (UTC)[reply]

I will try to get some of my friends in the industry to contribute here. It will be useful to us since we want to consider this form of knowledge capture for our work space also.

How about Linear Polyurethane

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As an avid sailor, I've used LP to paint several boats, but as of 2006-05-30, there is no mention of it in Wikipedia at all. I'd like to know how linear polyurethane differs from polyurethane. Also suggest adding its use as a paint-like coating, whether in a separate article linked from this one, or just in a subsection of this article.

I suspect that linear polyurethane uses a diol with a di-isocyanate to give linear polymer molecules, while other polyurethanes use a triol to give a cross-linked molecular structure. --GCarty 17:37, 30 March 2007 (UTC)[reply]

This article...

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This article is TERRIBLE!!!!. Is anyone monitoring this who knows anything about PU in general? (yes, I am going to start cpc) I guess not. Foam. More Foam, and did I mention Foam? PU foam by CO2. No other way is commercial, {There are many forms other than foam, but foam does dominate the volume of product produced}I guess? Not! Guys and gals, you've got several industries; of which, I'll admit, Foam is the largest (last I heard). I've not seen the breakdown on what categories PU is used in. Help is needed! Here's my take 1) Coatings, Adhesives and Sealants 2) Elastomers 3)Engineering Plastics (rigid to semi-rigid). OR 1) (belts, gaskets, bearings, wheels) 3) Coatings (sealants and adhesives, too) 3) Foam 4) Medical ... To the wise one who thinks that something with a molecular formula of ~80(ether/ester links)+2(urethane links)+1(urea link) should be named poly(urethane-co-urea), I say think again! {It may be unfortunate, but URETHANES has been choosen by the industry for the general class of polymers. We can't change this. Subclasses are called polyether urethanes and another subclass are ... urea-urethanes. The general class is found under urethanes, probably for historical reasons If you're going to get technical, then do it right! To the wise one who claimed urethanes don't penetrate wood, I say hog wash! Urethanes are used on high traffic wood surfaces all the time. They're some of the best field applied wood adhesives that exist. I guess you all are right in not mentioning the word "isocyanate" - since virtually all (but not quite) polyurethanes are made (produced) from them. And for the learned one who mentions not using them on antiques, I say 1) future restoration is made impossible (or very difficult) and 2) they are prone to discoloration and UV degradation (both aliphatic and especially aromatic isocyanate based) - this combination is a no brainer! you AVOID them cuz in 100 years they will need to be redone and you may destroy the antique trying to get them off! Their STRENGTH is their versatility; they range from soft enough to sleep on to hard enough to drive on. Their performance can be easily customized to meet the application. Alcohol, polyester, isocyanate, adhesion, polarity, hard segment-soft segment (block), abrasion, RIM, all are concepts (among others) that this article lacks and should (IMHO) cover. Not to mention the fact that PU's are really misnamed. I'd say start over. 208.230.167.50 16:40, 10 June 2005 (UTC)[reply]

Thanks for acknowledging the problem, and posing some constructive suggestions. I had the same emotional response to the hideous state of martensite when I first saw it, but you'll notice that the talk page of that article is free of my yelling at the prior editors who had contributed similar sophomoric, misleading half-truths to the ones you have enumerated here. Be bold and make some of these much-needed improvements, once you've calmed down a bit. Feel free to use this template:
==Uses==

===Coatings===
Basic overview

{{sect-stub}}

===Adhesives and sealants===

===Elastomers===

===[[Engineering plastic]]s===
Also, sign your rants with tildes (~~~~). Anonymous criticism may be less likely to be taken as constructive. Civility helps sometimes, too.

Cheers, The wise fool who thought poly(urethane-co-urea) was accurate

Polyparadigm 17:13, 10 June 2005 (UTC)[reply]

Inventor

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Also it must say that it was invented by Otto Bayer in 1937 - Germany. 200.30.252.51 22:21, 9 October 2005 (UTC)[reply]

This article needs to become "well rounded"

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No hazards of polyurethane are listed. This whole article looks like it was borrowed from somewhere on the net! 24.131.5.144 21:36, 16 December 2005 (UTC)[reply]

Hear, hear! Where is the information on health impacts?!

I'm told it's sometimes implanted into the human body. Since there hasn't been a controversy smilar to the one over silicone, perhaps it's not all that hazardous...though I'm sure the free monomers aren't very good for you.--Joel 01:54, 19 August 2007 (UTC)[reply]

You are right. There are several different medical applications of PU like casts for broken bones and it is also used in medical tubing. There are two problems: residual isocyanate groups and leakage of aromaic amines from the polymer matrix. I might have some time to update the article on this subject later this year.--Uvdluriaq (talk) 17:48, 25 May 2008 (UTC)[reply]

Removing wikify template

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I'm removing the wikify template because it doesn't apply here. What the article needs is expansion, restructuring and support from references. Alan Pascoe 23:10, 20 February 2006 (UTC)[reply]

Urethanes versus "urethane"

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The use of the term "urethane" for polyurethane resins has probably lead to mis-reporting of this substance to the USEPA under the Toxics Release Inventory (TRI). Urethane, ethyl carbamate, is a probable human carcinogen - polyurethanes are not. They are not listed as a TRI substance, either. Therefore, this clarification should help those required to submit TRI reports and those that need to interpret them. Oldsci 23:08, 12 May 2006 (UTC)[reply]

aquatic uses

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Somewhere in the back of my head is the thought that PU foam is used to core watercraft because it will not absorb water, unlike balsa. But I could not find an appropriate wiki template to cite "the back of my head". So if someone could confirm that and expand the watercraft section, thanks.--J Clear 02:04, 16 June 2006 (UTC)[reply]

It seems pretty absorbant when I spill coffee on my chair cushions. The reason it's used probably has more to do with manufacturing: you can just build a form, and pour the mix in, rather than trying to carve a big piece of wood and then build something around it.--Joel 01:57, 19 August 2007 (UTC)[reply]

polystyrene composites?

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Does anyone know if canned polyurethane filler can be used on polystyrene, or is it likely to dissolve the polystyrene? T boyd 09:19, 25 March 2007 (UTC)[reply]


Within reason it doesn't dissolve, I use a product called quicksand which is a car body filler on all grades of EPS. I also use a variety of polyurethane foams which are applied directly to EPS. N80krr (talk) 08:49, 24 February 2009 (UTC)[reply]

Chemistry Section

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I am interested to know if someone is putting together a chemistry section for this article. If the importance of this article is high, I feel that it is relevant to discuss the chemistry, the raw materials and the formulating of polyurethane systems separate from the production of finished goods.

P Cottontail 03:07, 16 April 2007 (UTC)[reply]

I've started the section on Chemistry. My intention is to discuss the chemistry, raw materials, and some formulating principles that are used to produce polyurethane polymers. I think some of what is in the Production section should be moved here, and that section revised to focus on the actual manufacturing/production process used to make finished goods.

P Cottontail 04:06, 21 April 2007 (UTC)[reply]

Can somebody please explain "urethane links" to a layperson? I was trying to learn the difference between urethane and polyurethane and I came across this idea of urethane links. Mattsonm 00:28, 19 August 2007 (UTC)[reply]

A urethane group is an entity in organic chemistry that sometimes appears as part of a polymer backbone. If a polymer has urethane groups in its backbone, it's called a polyurethane. --Joel 02:01, 19 August 2007 (UTC)[reply]

Used for high-performance Bushings and Mounts

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I'm surprised to see that this article doesn't mention the use of polyurethane in high-performance bushings and mounts. It's a common material in almost every high-performance automotive aftermarket suspension bushing and motor or transmission mount, and is a very popular upgrade amongst enthusiasts. Does anyone else feel like this should be added?

--Ioeth 21:48, 20 June 2007 (UTC)[reply]

As a matter of fact, I just noticed that the bushings article even mentions polyurethane as a material used to make them --Ioeth 21:51, 20 June 2007 (UTC)

I feel that from an encyclopedic article standpoint, it makes more sense to refer to polyurethanes from the bushings article as a material specifically used in their manufacture; and that the polyurethane article refer to bushings in a more general fashion. For example, stating polyurethanes are "used in the manufacture of high performance microcellular and elastomeric materials, such as bushings, dampers, tire compounds, die cutting pads", et cetera. Taking a broader view, the Uses section of the polyurethane article needs to be re-written this way. That is, polyurethane refers to general classes of material such as foams, elastomers, adhesives, sealants, and coatings, which are used to manufacture Items A, B, and C; and that the articles for Items A, B and C refer back to polyurethane as a material specific to their manufacture. Best Regards. P Cottontail 05:06, 27 June 2007 (UTC)[reply]

Polyurethane Rigid Foam

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[[User:Big Swede|15:26, 11 June, 2007 (PDT)

Polyurethane foams are also used extensively in structural and process-related applications. High-density expanded urethane foam products (10-lb per cubic foot up to 50-lb per cubic foot) can be used as tooling substrates, and as materials for visual styling exercises, composite lay-up tools, vacuum-forming tools, and for construction of mold-patterns.

Rigid, high-density polyurethane foam cores (6 lb to 24-lb per cubic-foot density)can be found in various marine applications (boat transoms, bulkheads, decks, stringers, and hatch covers, used in combination with polyester-resins and fiberglass.

Special forms of rigid polyurethane foam having hydro-static pressure resistance have been used to provide flotation or neutral buoyancy for robot submersibles and for International Space Station components in test-assembly at NASA. These foams are capable of withstanding up to 350 psi hydrostatic pressure, making them useful to water depths up to 600 feet.

They are also used (in their 18-20-lb density flame-retardant forms) in aircraft interior stow-bins, class-divider panels, and in sidewall-panel detail parts when processed with aircraft-grade composite prepregs and linings.

Rigid, medium-density polyurethane foams have been used in explosive-blast mitigation, where the cellular-structure of the foam provides a disruption to the propagation of explosive-blast shock waves through air. The energy absorbed by the crushing of these foams under blast-wave pressure, or the gas-pressure wave that follows an explosion, is considerable and has yet to be fully exploited in practice.

Rigid, high-density polyurethane foams with flame-retardant and intumescing additives are used in the construction of containment packages for nuclear and other hazardous-waste transport containers. These vessels are designed to absorb hi-G impacts and then withstand 2300-degree fuel pool-fire conditions while keeping the contents inside at temperatures below the boiling-point of water. Polyurethane foams are the materials of choice for these applications, replacing wood blocks and other more inconsistent and flammable materials.

Flexible, flame-retardant integral-skin expanded polyurethane foams are used in aircraft flight-deck applications for head-strike protection. Similar polyurethane foams have been used as comfort-padding and as part of the man-machine interface in man-portable anti-tank weapons, and military electronic-surveillance devices where a person may be in intimate contact with the instrument for long periods of time.

Molded rigid polyurethane foams are used as packaging materials in submunition-carrying weapons systems. They have also been used to create non-lethal "flash-bang" grenades, as well as stand-off devices for shaped-charge cutting systems for aircraft-ejection egress, and for detaching rocket motor nozzles from Space Shuttle SRBs.

High-density rigid foams (30-lb and higher) have been successfully employed as wood-replacement products in the construction of frozen-food warehouse structures. The foam, in block-form, is placed under roof columns between the column-base and the concrete footing, providing a thermal-break. This practice keeps cold inside the building, preventing freezing the soil around support structures. Wood materials used in these applications in the past were prone to rot and structural collapse, as well as water-uptake, limiting the lifespan of these warehouse structures while allowing the loss of considerable energy through the roof-columns.

Big Swede 22:31, 11 July 2007 (UTC)Big Swede[reply]

Soy Oil polyols

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In regards to the entry in the History section; the manufacture of polyols from soy oil as a "green" or an "environmentally friendly" process has been, in the United States at least, driven by soy bean growers and adjunct processors. Typical of the marketing campaign is the CompositesWorld article cited in the main article. I think the efficacy of soy oil polyols is overstated. A competing vegetable oil polyol is neat castor oil, which has been used to manufacture polyurethane products since at least 1974, see US Patent 3,959,573; or search the USPTO for "polyurethane castor oil" or "polyurethane" AND "castor oil". Castor oil, because of its high ricinoleic acid triglyceride content (about 90%), is a natural triol and requires little or no post processing to be used as a polyol. On the other hand, soybean oil has no hydroxyl content and must be post-processed to be used as a polyol. Poignant is the fact that the US accounts for about 1/3 of the world production of soybeans. India, on the other hand, is the primary global producer of castor oil. See the Wikipedia article on castor oil for comparative US domestic pricing, which is probably the real driving force behind the use of soy oil derived polyols.

P Cottontail 02:32, 14 August 2007 (UTC)[reply]

Production

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My intention is to reseed the information in the Production section, as intact is possible, into the existing History and Chemistry sections, and to-be-added Raw materials, Formulating, and Products (finished goods) sections. I would like to have the Production section describe the physical process and manufacturing of Polyurethane goods, although I may incorporate that info into the Products section.

Feedback on this is welcome.

Cheers,

P Cottontail 16:02, 19 August 2007 (UTC)[reply]

Structure of Polyurethane article

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I am proposing to structure this article as follows,

I. History
II. Chemistry
III. Raw Materials

A. Isocyanates

B. Polyols
C. Catalysts
D. Surfactants
E. Flame retardants
F. Fillers

G. Other Additives

IV. Applications

A. Flexible Foam

B. Microcellular Foam
C. Integral Skin Foam
D. Rigid Foam
E. Elastomers
F. Adhesives and Sealants

G. Coatings

V. EH&S
VI. Process Equipmment

P Cottontail 17:14, 20 August 2007 (UTC)[reply]


LOL, worthy on mention somewhere later in the article under membranes or coatings, I am sure. Although they go hand in hand with HR bedding, my guess is the absolute poundage is skewed towards the latter. P Cottontail 20:35, 22 August 2007 (UTC)

Subheaders

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Regarding reducing the number of subheaders, I am all for it. In my opinion, the way the subheaders are currently organized is wrong for the article. Things like glue, bookbinding, watercraft, watchband binding, tennis grip wraps, et cetera should be removed completely. I think most of their content belongs in an article titled the subheading. Most warrant incidental mention under subheadings such as flex foam, rigid foam, integral skin foam, adhesives and the like. I'll get around to it; I want to gather better content first before mucking up whats already in the article. P Cottontail 21:44, 27 August 2007 (UTC)[reply]

PU synthesis mechanism

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Hey - I noticed a few mistakes in the "PU reaction mechanism catalyzed by a tertiary amine" scheme, so I took the liberty of uploading a corrected version (its called Polyurethane_mechanism.png). I am new to Wikipedia so I can't figure out how to make it look right on the page - anyone care to help? Groove Champion (talk) 04:37, 18 January 2008 (UTC)[reply]

temperature service range?

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What is the typical temperature service range of the cured adhesive? -69.87.200.177 (talk) 23:34, 29 April 2008 (UTC)[reply]

Replacing clay wheels

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Comment and question removed from article for consideration here:

Skateboard wheels had previously been made of clay, and broke constantly. {Can somebody check this? I believe they were made of a phenolic material, and never knew of one breaking. The problem was that they were sensitive to debris, and every tiny stick or pebble would stop the board dead, while you went flying. (In regards to phenolic, you would go flying, however phenolic will begin breaking if worn then exposed to moisture, the wheel will baloon and chunk.}

--Old Moonraker (talk) 12:35, 8 August 2008 (UTC)[reply]


Degradation

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Does anyone have any data on whether polyurethanes degrade into their component substances over time? I have repeatedly purchased plastic drink mugs whose lids are made of a black plastic (unhelpfully labeled with the "7-Other" SPI recycling code) which I suspect must be polyurethane, because after a few months it starts to develop a smell distinctly reminiscent of urine. This leads me to suspect the polyurethane is breaking down and releasing urea (into my drinking glass!), a disturbing possibility I'm looking to investigate in the hopes of figuring out how to avoid future incidence. This article doesn't appear to address the question of what happens to polyurethanes over time, so my theory remains unproven. —Preceding unsigned comment added by Wpell (talkcontribs) 03:17, 14 October 2008 (UTC)[reply]

Answer: Polyurethane will actually break down to amines, which have "fishy" or urine smell. I would never use polyurethane products for food use, even though some of them are FDA approved. All polyurethanes undergo hydrolysis, sooner or later (even hydrolysis-resistant ones). Especially, if they are in contact with hot water (or vapors). Source. — Preceding unsigned comment added by Melnichek (talkcontribs) 16:49, 7 December 2011 (UTC)[reply]

Flexible Foam

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I used polyurethane foams at my place of work but I always use rigid high density foam. I'd like to know what the diffences are and how to produce/use a flexible foam such as the one used in mattresses or the example of the car seat. N80krr (talk) 08:53, 24 February 2009 (UTC)[reply]

Apart from the obvious physical differences between rigid foam and flexible foam, the main difference is the size of the polyols used to make the polyurethane. Rigid foams use low molecular weight polyols while flexible foams use high molecular weight polyols. If the functionality (average number of reactive groups per molecule) is the same, this means that the rigid foams contain more crosslinks per unit mass than flexible foams. (Polyols for rigid foams often have a higher functionality than those intended for flexible foams, increasing the effect even more.) Imagine a lattice-work tower: as you increase the number of cross-braces the stiffer (more rigid) the tower becomes. The key then to making flexible foams is to use the right polyols, and these are typically trifunctional with molecular weights between 3000 and 6000 Daltons. Contact me on my talk page if you want more details. Silverchemist (talk) 14:41, 24 February 2009 (UTC)[reply]

Role of Nopco?

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My father's greatest discovery as a stockbroker was a mid-sized independent chemical company, called Nopco, based in New Jersey — he made a lot of money for himself and all his clients by investing just as they were developing polyurethane, circa 1955-57. I had the impression they'd actually invented the stuff. They must have made some major development. We even had bedtime stories about Polly and Urethane yearning for each other through the glass of their test tubes, until finally their desire became so overwhelming the glass burst open and they merged in bubbling smoking ecstasy on the laboratory floor, and were discovered exhausted but united in the morning, in the form of a sponge.

Nopco had a few other minor successes, but most of the company's value was due to its innovations in polyurethane. Nopco was purchased by Diamond Shamrock in the 1960s. Chelydra (talk) 12:16, 24 May 2009 (UTC)[reply]

A Google search found a cache of http://www.utahfoam.com/aboutus.asp. (snapshot of the page as it appeared on 24 Mar 2009 13:29:41 GMT. No direct access to the web page.) It includes this statement: "Nopco was the first licensee of the Urethane patents provided by the federal government after the Second World War." It also mentions Nopco's relevant patents, manufacturing innovations, etc. So it would seem that Nopco was one of several American companies that got a piece of I.G. Farben when war spoils were passed around. If anyone is overhauling the article, Nopco's role apparently deserves a mention.


As of May 24, 2009, there's a lovely image of a Nopco stock certificate here: http://www.scripophily.net/nopchemcom19.html Chelydra (talk) 12:55, 24 May 2009 (UTC)[reply]

Chem Box

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I think this article could be improved by having an Infobox. I don't know enough about polymers to know if the Chembox Template is appropriate - if it isn't perhaps a specific infobox type for polymers is needed? --Ozhiker (talk) 11:06, 13 August 2009 (UTC)[reply]

A chembox is certainly a good start! --Dirk Beetstra T C 11:43, 13 August 2009 (UTC)[reply]
Polyurethane is a class name. Even then, we can fix the chembox for the simplest/popular one. I tried to gain data and failed. This is all I have got,
{{Chembox
| ImageFile = Polyurethane chemical structure.PNG
|  ImageSize =
|  ImageAlt =
| IUPACName =
| OtherNames = polycarbamate
| Section1 = {{Chembox Identifiers
|  3DMet =
|  Abbreviations = PU, PUR
|  ATCvet =
|  ATCCode_prefix =
|  ATCCode_suffix =
|  ATC_Supplemental =
|  Beilstein =
|  CASNo =
|  CASNo_Ref =
|  CASNos =
|  CASOther =
|  ChEBI = 60737
|  ChemSpiderID =
|  DrugBank =
|  EC-number =
|  EINECS =
|  EINECSCASNO =
|  Gmelin =
|  InChI =
|  KEGG =
|  MeSHName =
|  PubChem =
|  RTECS =
|  SMILES =
|  UNNumber =
}}
| Section2 = {{Chembox Properties
|  Formula =
|  MolarMass =
|  Appearance =
|  Density =
|  MeltingPt =
|  BoilingPt =
|  Solubility = }}
}}
There are no article on it on Pubchem or CAS. Vanischenu mTalk 00:20, 20 July 2012 (UTC)[reply]

Transparent Polyurethane exist?

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I read in a site [[1]] that Transparent polyurethane exists and is used as a better option than polycarbonate. Is this true?Agre22 (talk) 16:27, 13 October 2009 (UTC)agre22[reply]

PUaminemechanism.png is WRONG

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There are a few things chemically wrong with the mechanism as shown. After the second step there is a HYPERVALENT carbon ("texas carbon" or a carbon with 5 bonds). One of the bonds should be transferred to the oxygen. Also after the second step, the arrow points from the proton to the electrons--- by conventions arrows show the movement of ELECTRONS, not of protons. The arrow should point the other way.

I will gladly redraw the mechanism if no one has objections. --Narkissos (talk) 22:15, 27 January 2010 (UTC)[reply]

I can't tell you if you are right or wrong, but you'll probably have a better bet of getting your question answered at Wikipedia talk:WikiProject Chemistry. Also, you might want to check out Wikipedia:Manual of Style (chemistry)/Structure drawing. Wizard191 (talk) 19:04, 28 January 2010 (UTC)[reply]

Chemistry

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Isocyanates will react with any molecule that contains an active hydrogen.

What's an "active hydrogen"? It is the hydroxyl oxygen that reacts with the isocyanate, not the hydrogen. And isocyanates are anyway likely to react with any nucleophile, not only those with a hydrogen bound. —Preceding unsigned comment added by 130.233.243.229 (talk) 23:22, 13 May 2010 (UTC)[reply]

Why elastomeric?

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The introduction should have a (very) few well chosen words on why these polymers can be more elastomeric than others. It might help if some of the words used are later used in the chemistry secion by way of explanation.173.73.46.26 (talk) 20:26, 20 November 2010 (UTC)[reply]

Too specific, but also too vague

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I'm an organic chemist, and I don't think this was written by a chemist at all. The references seem to suggest it was by people in the polyurethane industry. It sounds just slightly too general to be 'written like an advertisement', but it is more a listing of what the industry is capable of doing than a Five Ws discussion of what polyurethane is.

The chemical content is minimal. The generalized reaction and mechanism do not make it clear that R2 has more than one hydroxyl group, and so one cannot easily see how the polymerization would continue. Why is the reaction with water important? It can be misleading even if it has applications in making foams, as this is not the polymerization reaction. (Also, bismuth octanoate is not organometallic; it contains only Bi-O bonds and no metal-carbon bonds.)

For an article that seems so specialized, there is a distinct lack of specificity where it really counts. "The choice of initiator, extender, and molecular weight of the polyol greatly affect its physical state, and the physical properties of the polyurethane polymer." How? Some examples should be given, probably in table form. There are too many sentences that essentially allude to the complexity of making polyurethanes and the diversity of possible products without giving detail as to how they are made.

I think the article does not suit the audience; it might be appropriate for a wiki on polymers, but not for a general audience. What is polyurethane? How is it made? What are the two parts? What makes it hard, soft, or foamy? I think that most readers are more interested in that than on the effects of the Montreal Protocol on the PU industry (that may merit an article of its own, however.)

I read the article after it was suggested to a high school student interested in skateboard wheels. That's not mentioned, and it represents a missed opportunity to demonstrate chemistry in everyday life. I do not think the content should be obliterated, but it requires substantial reorganization if it is to be useful to general audiences with varying levels of technical knowledge. I don't feel bold enough to make these changes, nor do I have all the specific knowledge, but I think a polymer chemist and/or a specialist in the industry could do so.

Roches (talk) 05:51, 12 May 2011 (UTC)[reply]

I agree. A table of physical properties, eg each row for a general (or specific) type of PU (incl. foams) with columns for safe temperature ranges, ignition point, etc would be of practical benefit to people selecting materials (the next level of detail would be to obtain datasheets for specific products). FreeFlow99 (talk) 18:02, 19 July 2021 (UTC)[reply]
These comments are helpful. Articles on polymers are difficult for editors here because we are mainly academic and the few industrially trained editors tend to be specialized in certain technologies. Urethane is a huge specialized industry, so we are stuck. All you can do is identify some of the most serious problems so that editors can at least remove misinformation. My guess is that few readers are looking for niceties of chemistry, but instead they want to get a grip on what is in some broad sense and how urethane compares with other materials. --Smokefoot (talk) 02:28, 21 July 2021 (UTC)[reply]
Thanks Smokefoot. Perhaps it would help if there was one page for Polyurethane, the chemical, and separate pages for each material form, eg open celled foam, closed cell foam, adhesive, rigid hard plastic, etc that describe the material's properties?
OK, let me try that idea.--Smokefoot (talk) 14:56, 21 July 2021 (UTC)[reply]

Cleanup

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The article IS lengthy, and as such, tends to lose direction, and it does need editing. There are a number of errors, or misleading statements, that need to be expanded on or corrected. For example,under isocyanates: "For example, light stable coatings and elastoemrs can only be obtained with aliphatic isocyanates." The writer either is not aware of diisocyanates like TMXDI, where the isocyanate functional group is hindered by the addition of 2 methyl groups on the C attached to the aromatic ring, which eliminates resonance with the aromatic ring and the aromatic sextet, or didn't bother to add that feature. I world dearly love to re-write the entire article, but I don't have the time. I have been in polyurethane research and development since 1960, and am still working full time in that arena, currently as senior scientist in a corporation. I also taught advanced chemistry courses at U Mass, in the Continuing Ed division, for 30 + years. Polyurethane chemistry is a wonderful and can be quite technical arena. There are so many reactions and usable monomers, so many manufacturing techniques, that even today, new formulas and new patents are constantly being issues. Polyols where one end functional group is replaced by a reactive acrylic functional group, etc. Hydromeds, TPUs, microcellular foams, fibers, adhesives, coatings and so many other areas. ````HEG2011 — Preceding unsigned comment added by HEG2011 (talkcontribs) 16:05, 3 June 2011 (UTC)[reply]

Sounds like you are well versed on this topic. As such, make edits as you see fit. If others disagree they will voice their opinion and it can be discussed on the talk page. Wizard191 (talk) 13:28, 6 June 2011 (UTC)[reply]
Knowing a bit about chemistry myself, I agree with shortcomings mentioned above.

I believe a lot of people might search Polyurethane to find out what it's soluble in. Many do-it-yourselfers want to know how best to clean up spills and residue on hands, clothing, projects, etc. This seems like a glaring omission to me; it was in fact the reason I came here in the first place.

Secondly, Quite some tonnage of polyurethane variants are manufactured annually for the agricultural industry for use as a slowly degrading coating for time released fertilizers, namely urea crystals. This should be included in industrial uses section.Mykstor (talk) —Preceding undated comment added 17:46, 24 August 2011 (UTC).[reply]

Way too technical

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As a layman, with no chemical background whatsoever, I looked to this article for a layman's explanation of the subject. What I found, however, seems more suited for an advanced textbook, but not very helpful to me, at least. I suggest the article be revised into a general summary of the subject, and not try to duplicate technical information that can be found in a Chemistry textbook.66.108.5.20 (talk) 07:10, 21 July 2012 (UTC)[reply]

This is still an issue :-( Aviad.rubinstein (talk) 18:40, 3 October 2020 (UTC)[reply]

Yes, please make the introduction much more layman-friendly, as per WP:TECHNICAL. -- SimonEast (talk) 06:10, 17 May 2021 (UTC)[reply]

urethane rubber

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I can't find an article on Urethane Rubber; this is the nearest article. Does anyone know enough about Urethane Rubber to at least create a stub? FreeFlow99 (talk) 21:02, 28 April 2015 (UTC)[reply]

Assessment comment

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The comment(s) below were originally left at Talk:Polyurethane/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Comment(s)Press [show] to view →
Recommendations, generated by the peer-review script, for further improving the article. These are straightforward WP compliance issues, mostly easily correctable. Typically, these recommendations should be dealt with for an A-Class article in WP:Chem.
  • Please expand the lead to conform with guidelines at Wikipedia:Lead. The article should have an appropriate number of paragraphs as is shown on WP:LEAD, and should adequately summarize the article.[?]
  • There may be an applicable infobox for this article. For example, see Template:Infobox Person, Template:Infobox School, or Template:Infobox City.[?] (Note that there might not be an applicable infobox; remember that these suggestions are not generated manually)
  • Per Wikipedia:Manual of Style (numbers), there should be a non-breaking space -   between a number and the unit of measurement. For example, instead of 03 mm, use 03 mm, which when you are editing the page, should look like: 03 mm.[?]
  • This article may need to undergo summary style, where a series of appropriate subpages are used. For example, if the article is United States, then an appropriate subpage would be History of the United States, such that a summary of the subpage exists on the mother article, while the subpage goes into more detail.[?]
  • Please make the spelling of English words consistent with either American or British spelling, depending upon the subject of the article. Examples include: fiber (A) (British: fibre), fibre (B) (American: fiber), recognize (A) (British: recognise), ization (A) (British: isation), isation (B) (American: ization), catalyze (A) (British: catalyse), mold (A) (British: mould), mould (B) (American: mold), molt (A) (British: moult).
  • As done in WP:FOOTNOTE, footnotes usually are located right after a punctuation mark (as recommended by the CMS, but not mandatory), such that there is no space in between. For example, the sun is larger than the moon [2]. is usually written as the sun is larger than the moon.[2][?]
  • The article will need references. See WP:CITE and WP:V for more information.[?]
  • Please ensure that the article has gone through a thorough copyediting so that it exemplifies some of Wikipedia's best work. See also User:Tony1/How to satisfy Criterion 1a.[?]
You may wish to browse through User:AndyZ/Suggestions for further ideas. Thanks, Wim van Dorst (Talk) 20:10, 24 October 2007 (UTC)[reply]

Last edited at 20:10, 24 October 2007 (UTC). Substituted at 03:13, 30 April 2016 (UTC)

Is this the fire hazard you're looking for?

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Having just added a paragraph based upon an article in The Sun about the Grenfell Building fire in London, I am officially uncertain. The article in The Sun points the finger at polyurethane in external insulation as causing the fire. When I look at the Wikipedia page that discusses the fire, though (Grenfell Tower fire), it refers to polyethylene. This is a bit of a surprise, if I am correct in understanding how polyethylene burns (and if Wikipedia is correct about it).

Is anyone able to confirm which material is correct? Given discussions I have heard about 'the proper material' vs. 'a cheap knock-off', it may be too early to be confident in this, unless there is some information I haven't seen about the Dubai fire; the correct information may only be available once the inquest hears relevant evidence. At that time, presumably, it will be possible to ensure that this article, the (Grenfell Tower fire) article, and if necessary Wikipedia's polyethylene article can be updated as appropriate. Thanks. Ambiguosity (talk) 10:00, 18 June 2017 (UTC)[reply]

Given that the Sun article does not (any longer?) mention polyurethane, while the BBC mentions polyethylene, I've gone ahead and removed the paragraph in question. goffrie (talk) 01:43, 5 August 2017 (UTC)[reply]

Removal of info on banning of blowing agents

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Does anyone know why this edit was done? editor is not around or I'd ask. Teanks! HLHJ (talk) 05:01, 9 May 2020 (UTC)[reply]

@HLHJ: Appeares to have been a promotional account attempting to censor. I have restored the content. The {{expert needed}} tag was unnecessary. –LaundryPizza03 (d) 01:41, 3 June 2021 (UTC)[reply]
Sorry, LaundryPizza03, I didn't know that account was promotional, so I thought there might be a better reason which I didn't understand. Sometimes it would be helpful to have possible-promotion flags in edit histories. Thank you for fixing. HLHJ (talk) 01:25, 4 June 2021 (UTC)[reply]

Split proposal

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As discussed somewhere above, some readers and editors find this article too broad. So the idea is to carve out a shorter article on polyurethanes mentioning precurors and general properties. Most of the current content would end up in a more applied article focused on production and physical properties of commercial products.--Smokefoot (talk) 15:07, 21 July 2021 (UTC)[reply]

I'm not sure if a split alone will help here. Splits work well when the content is good, but there's too much of it. A lot of the content here is poor, the 'chemistry' section being an obvious example.--Project Osprey (talk) 18:50, 22 July 2021 (UTC)[reply]
Good point. I guess my thinking was that we could write something small and decent focused on basic chem & properties and move (ok, dump) all the rest of the content into a more amorphous article about commercial and engineering aspects. In fact I was wondering if such a strategy might work for other major polymers such as PE, PS, and terephthalate. I worry that some person wants a thumbnail sketch of the material they have, but dont want to wade through these large articles. --Smokefoot (talk) 03:39, 23 July 2021 (UTC)[reply]
Long articles are definitely a turn-off and I agree that many (most?) of our plastics pages have become so disorganised that they're uninformative. I feel that this page could be a lot shorter if it were better written. Pie charts showing a breakdown of applications and chemical make-ups might shown dominant examples, which could then be focused on. Long and tortuous descriptions of its many possible indigents and their structure-property-relationships could be greatly aided with example images, perhaps with one of the final structure showing the presence and significance of the incorporated groups. In fact, we don't kneed all that information in one section, we're not writing Chem Rev here. If we organise the page by applications we can explain the chemistries much more simply: "these ethoxylates coil up like springs but can be pulled straight, making the foam elastic" or "when the glue is heated the oxime–carbamate bonds break, but when it cools they reform and it sets hard". This could help lay-readers by keeping the chemistry simple and anchoring it to something they know.

Reaction polymers

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The chemistry section currently describes these as being 'reaction polymers' - but that's not a term I'm familiar with and the google results for it are weak. It seems to originate from a book title rather than any technical usage. I think condensation polymer probably more appropriate. --Project Osprey (talk) 09:29, 3 August 2021 (UTC)[reply]

Small error in scheme in "chemistry"

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The bond depicted in the scheme says "polyurethane" bond. This is not the case, or is a urethane. 82.174.79.67 (talk) 23:33, 29 December 2021 (UTC)[reply]

In this scheme File:Polyurethane_synthesis.tif... we'll have to make an new image to fix that, which is annoying. --Project Osprey (talk) 00:45, 30 December 2021 (UTC)[reply]