Talk:Conductive polymer

Error in introduction

In the intro, it is stated that "until recently" it was thought that plastics are pure conductors. This is not exactly true. It was known in 1950 or earlier that some plastics can conduct well. See for proof the article in Life magazine, http://books.google.com/books?id=T0EEAAAAMBAJ&lpg=PP1&pg=PA52#v=onepage&q&f=false. —Preceding unsigned comment added by 67.243.140.144 (talk) 05:17, 18 June 2010 (UTC)

Yes, that sentence was not neutral (Ugh, recently ..) and I went bold and removed it. However, it is certainly true that most pure organic materials are insulating. Materialscientist (talk) 05:26, 18 June 2010 (UTC)

Markite

Changed siloxanes and organosilanes to the less specific organosilicon plastics. Because these compounds have military uses, I suspect some of the early work was classified. Very interesting-- this is how wikipedia is supposed to work.Nucleophilic (talk) 14:57, 13 July 2010 (UTC)

There is no clear evidence in the given citations that Markite is in fact an organosilicone plastic or polymer. The two popular scientific articles don't elucidate the composition of Markite. The Army Materials and Mechanics Research Center report describes the material as an inorganic silica/silica composite derived from multiple pyrolyses.

The only patent from Markite Intl. Corp. in respect to conductive polymers is FR1111057A (publ. 1956-02-22) with the title „Matières plastiques conductrices et leur procédé d'obtention“ describing mixtures from conductive metals or e.g. carbon black with plastics.

The article in LIFE from 26th Dec. 1949 mentions Dr. M. A. Coler (New York Univ.); his patents (US2683669A, US2761854A, US3948812A and others) comprise mixtures of organic plastics or ceramics with e.g. metal powders.

So Markite is not at all an intrinsically conducting polymer and should be denoted as a mixture of materials or just a coated plastic. I have revised that in the meanwhile. (Rolf Wallenwein, Germany) 84.171.191.26 (talk) 16:05, 1 October 2010 (UTC)

I am in acccord with this. Contrary to my original impression, markite is apparently not really a conductive polymer per se. Bummer. I may remove the reference myself, unless somebody objects or wants to do it first. Nucleophilic (talk) 18:41, 1 February 2011 (UTC)

recent changes re "structure and morphology"

"Materialscientist", can you explain why you removed the recent changes, and you only shortly commented "self promotion"? what kind of self-promotion was there? anything unreliable? pls explain —Preceding unsigned comment added by 113.112.252.14 (talk) 13:09, 9 January 2011 (UTC)

Promotion (self or not) refers to a few attempts to add a primary source (by Bernhard Wessling from Enthone, Inc.), presenting that source as a review of properties and applications of conducting polymers. As I mentioned to you before, we need reliable, secondary sources (for example, books which you also added to this article). The article you mentioned is published recently, in a minor journal, and claims to present a "new structure model for the organic metal polyaniline" - a well-studied material. In short, we need results which are widely accepted by the scientific community. Wikipedia is not a venue to promote new theories. Materialscientist (talk) 13:34, 9 January 2011 (UTC)

regarding conductive polymer structure / morphology with conductivty relationship, there is no widely accepted conclusion, and the article I am citing is a primary source reviewed by neutral referees as any other primary source Wikipedia is citing in this article. The "conductive polymer" article almost exclusively cites primary sources, except for ref 7, 14, 15. Your statement is not balanced in view of the remaining article and references. If you would take out any other primary source, I would not disagree. But then, what would remain? Therefore I suggest you to restore what I had added before, or you give more objective reasons.183.37.174.143 (talk) 13:44, 9 January 2011 (UTC)

Let us be specific. The text I removed was
A recent article by Bernhard Wessling in "Polymers" (http://www.mdpi.com/2073-4360/2/4/786/) is reviewing the experimental and (non-equilibrium thermodynamical) theoretical knowledge about Polyaniline and its dispersions and outlines a new concept for the structure of Polyaniline including a concept for a structure / conductivity relationship ^[1]. Starting from the understanding of Polyaniline (and conductive polymer) dispersions as dissipative structures which can be described by non-equilibrium thermodynamics, the author describes the hitertho unpublished formation of complexes between the Organic Metal Polyaniline and conventional metals like Cu, Fe, In and others (the basis for most of the applications). Furthermore, he shows experimental evidence that advanced dispersion techniques lead to even higher conductivity (in contrast to naive predictions). The higher conductivity is accompanied by changes in morphology and x-ray spectra. These changes are (together with other experimental evidence) interpreted with a new structure model, according to which short helical polyaniline chains are brought into some higher degree of order.
It does read as promotion of that article rather than an attempt to add encyclopedic information (and as I mentioned that article is not a review). Please stay with your edits - other primary sources are to be dealt with in due course. Materialscientist (talk) 14:04, 9 January 2011 (UTC)

I do not agree with your statement, because the article cited is referenced neutrally and objectively. But I do not want to start a edit / undo battle, it is not worth the effort. If Wikipedia prefers to have only a certain selection of primary sources (where secondary sources are not availeble), then be it. Wikipedia can choose to be biased.183.37.174.143 (talk) 14:25, 9 January 2011 (UTC)

I would like to comment to one additional of your comment: "Wikipedia is not a venue to promote new theories" - please be aware that the whole area of conductive polymers is new, and there is no reliable accepted theory at all yet. Everything is still disputed, especially whether condutivity is a 1D phenomenon or in fact more a 3D one, very basic questions. If, then Wikipedia should show this. But right now, it shows just one single aspect of it and pretends this were the truth. That is what I call "biased". So be it. 183.37.174.143 (talk) 15:16, 9 January 2011 (UTC)

effect of crystallinity on conductivity

"materialscientist", you removed the addition of "it is assumed" which I had added to this text: "Generally, conductivity should be higher for the higher degree of crystallinity and better alignment of the chains;"

Please show me one clear and undoubtful experimental evidence for the statement as you prefer to write.183.37.144.55 (talk) 03:15, 10 January 2011 (UTC)

(i) It is a common weasel phrase in English; (ii) it is not assumed, but well known for many systems. On the contrary, it is very, very uncommon to see a decrease in conductivity with increasing disorder. Materialscientist (talk) 04:09, 10 January 2011 (UTC)

I do not say that conductivity decreases with increasing order; what I say is: there is no clear evidence (if at all) that one can see any increase with a "higher degree of crystallinity and better alignment of chains". This is a statement simply not backed up by experimental evidence even though many people believe so.

"increase of order" is something different, there are other types of "order" than only "crystallinity" or "alignment of chains". 183.37.147.165 (talk) 04:43, 10 January 2011 (UTC) show me the evidence for "conductivity should be higher for the higher degree of crystallinity and better alignment of the chains", then I will stop arguing. 183.37.147.165 (talk) 04:51, 10 January 2011 (UTC)

Speaking in general, there is more than enough evidence that higher degree of crystallinity (in organic polymers specifically, see, e.g. doi:10.1088/1468-6996/10/2/024314, doi:10.1088/1468-6996/10/2/024313) increases the conductivity. Although I'm skeptical it was not shown in PANI and PEDOT, I can't give you a reference on the fly, which is why I left this statement in the article. Please re-read it and find that it does not contradict what you're saying. Materialscientist (talk) 04:52, 10 January 2011 (UTC)

sorry, both of these references do not talk at all about conductive polymers; they are dealing with organic (small molecule) semiconductors for the use as field effect transistors. Such materials are a) not polymeric b) not conductive d) neutral (and not doped) but d) highly crystalline. In these materials, with better crystallinity the electron *mobility* (which is needed for FETs) is increased. This has nothing to do with conductivity in conductive polymers.183.37.159.82 (talk) 06:04, 10 January 2011 (UTC)

Actually, this phrase "Generally, conductivity should be higher for the higher degree of crystallinity and better alignment of the chains" is stating something which (upon my view) is wrong, simply not correct. But I had let it stay there with the relativation "it is generally assumed". If you insist that the phrase is correct and there is evidence, show me the evidence and the references! The references you showed me, by the way, had been primary sources. 183.37.159.82 (talk) 06:07, 10 January 2011 (UTC)

Quick note: no, those are not primary, but secondary sources - they are reviews summarizing work by other authors rather than presenting their own original research (as the ref you add). They are not ideal, just what I had under my hand right away. They do speak of polymers too. They are conductive, but not as much as those described in the article. Physically, carrier mobility must decrease with decreasing crystallinity. Alignment is less crucial. Materialscientist (talk) 06:12, 10 January 2011 (UTC)

ok, I overlooked that these were review articles. But definitely: they are not talking about *conductive polymers*, and not about *conductivity*. They are talking about neutral semiconducting materials, most of them small (non-polymeric) molecules, only a few oligomeric ones, but these also neutral, not doped, not conductive. All the materials discussed in these references are semiconductors, and the topic being discussed is the carrier mobility which has nothing to do with the conductivity phenomenon in doped organic conductive polymers. 183.37.159.82 (talk) 06:28, 10 January 2011 (UTC)

How comes? The behavior of conductivity is actually more complex in semiconducting polymers because both concentration and mobility change. In conductors, the concentration is already high and it is the mobility which determines the conductivity, and this is what those papers are talking about. Please try checking Google books - the answer is there, for your polymers as well. I will too, but not right now. Materialscientist (talk) 06:39, 10 January 2011 (UTC)

The conductivity mechanism for semiconductors is completely different than for conductors. In semiconductors, you have a band gap, in conductors, you don't have. You can not deduct what influences the conductivity of conductive polymers by looking at what influences the charge carrier mobility in semiconductors. 183.37.159.82 (talk) 06:50, 10 January 2011 (UTC)

The most interesting conductive polymers (those having a high conductivity) are either close to be metals or even already are true metals. If your above statement would be correct, then you could learn something about the electron transport and conductivity of Copper by looking at a Silicon or GaAs semiconductor, which is not possible. In semiconductors, the electrons are located and need to one by one become excited to cross the band gap, in metals, you have an electron cloud moving through the metallic lattice (and the electrons are never located but delocalised). You simply can not put semiconductors and metals into the same pot. 183.37.159.82 (talk) 06:58, 10 January 2011 (UTC)

I do understand the difference between transport in semiconductors and metals. Note that grain boundary scattering works in both as a mechanism reducing mobility in nano/polycrystals - which is a major reason of conductivity increase with crystalline quality. Carrier excitation is a separate matter. Materialscientist (talk) 08:37, 15 January 2011 (UTC)

relationship between structure and conductivity

hello "materialscientist", noted your changes and appreciate you at least took some portions of my changes. However, I still can not accept your biased deletion of the link to Wessling's article in "Polymers", http://www.mdpi.com/2073-4360/2/4/786/, which describes a new proposed structure / conductivity relationship model.

The article "Conductive Polymers" is full of unconfirmed or only partially accepted theories, and even some very questionable statement like this one

"Thus, Inzelt notes that,[1] while the Nobelists deserve credit for publicising and popularizing the field, conductive polymers were " ..produced, studied and even applied " well before their work.[33]"

is included. Where were "conductive polymers" really applied *before* the noble prize winners have published their first doping of Polyacetylene? Even until mid of the 90s, there was almost no real application!

Moreover, the majority of the references are primary ones, so this article should correctly reference the fact that "conductive polymers" are far from being well understood, and that what is "accepted" does by far not explain the experimental facts. 183.37.138.129 (talk) 14:50, 15 January 2011 (UTC)

Inzelt is apparently well-known in conductive polymers and his textbook is part of an invited review series. Tracing it back, the exact quote is from a review of his textbook, at [2]. The cites need to be made clearer as to which says this, which I will do unless someone else wants to. These are quite high on the secondary/tertiary source scale, see WP:RS. BTW, I don't know enough about this area to know about the "applied". But that is what the source says. However, there does seem to have been a lot of "lost" work in this area. I suggest perusing the other early citations. And yes, this does seem a very complicated situation, with multiple discoveries and rediscoveries spread out over decades.Nucleophilic (talk) 05:32, 4 February 2011 (UTC)

Oops. Link above directly to review does not work. The correct one is [3]. Again, I do not know what "applied" means here. Maybe somebody was using conductive polymers as electrodes, or whatever. Exact quote:

• " Chapter 8 (of Inzelts textbook), Historical Background (Or: There Is Nothing New Under the Sun) reminds us that even before the great trio (Shirakawa, McDiarmid and Heeger), who earned Nobel Prize for the discovery of conductive polymers, certain conductive polymers were produced, studied and even applied. So, is there really anything new under the Sun? No, there is not, but we have not been aware of CPs, as of the materials that offer a variety of new possibilities. So the real era of conductive polymers chemistry/electrochemistry has started actually thanks to a student mistake, and clever scientists wholearn on/from mistakes." Nucleophilic (talk) 17:25, 5 February 2011 (UTC)

Discussion on talk:polyacetylene

We are having an interesting discussion over on talk:polyacetylene, if anyone is interested. Nucleophilic (talk) 13:31, 12 February 2011 (UTC)

There is more relevant discussion evolving on Talk:Nobel Prize. Nucleophilic (talk) 21:20, 24 February 2011 (UTC)

"Well-studied classes"

I'm not a huge fan of that phrase, since it seems like what is and isn't 'well-studied' is both debatable and time-sensitive. I'm not an expert on the subject, but I would argue that poly(fluorene) seems quite well-studied. I can't think of an alternative phrasing that I like better, so my inclination is just to do away with the bold and italic altogether, and to not make a distinction between 'well-studied' and 'less well-studied.' Thoughts? Anneagain (talk) 08:29, 27 April 2011 (UTC)

Archived

I've archived the discussions from before 2010. Antony–22 (^talk⁄_contribs) 19:26, 18 March 2011 (UTC)

Processability - article is contradictory

Hello - newbie here. :)

This article appears to contradict itself on the subject of the processability of conductive polymers. The introduction states:

The biggest advantage of conductive polymers is their processability, mainly by dispersion.

(Incidentally: advantage over what?)

The section "Properties and applications" begins:

Conductive polymers enjoy few large-scale applications due to their poor processability.

I am not a subject-matter expert, but it seems to me that these assertions are at odds. (Reading the rest of the article, I am more inclined to believe the latter account.)

Benjjuk (talk) 12:10, 19 January 2012 (UTC)

Proposed changes to the history section

There must be more reviews that discuss the history and development of conducting polymers than the two currently cited:

• Hush, Noel S. (2003). "An Overview of the First Half-Century of Molecular Electronics". Annals of the New York Academy of Sciences. 1006: 1. Bibcode:2003NYASA1006....1H. doi:10.1196/annals.1292.016. PMID 14976006. {{cite journal}}: More than one of |pages= and |page= specified (help)

• György Inzelt (2008). Conducting Polymers A New Era in Electrochemistry. Springer. pp. 265–269. doi:10.1007/978-3-540-75930-0_8. ISBN 978-3-540-75930-0.

I performed a quick Web of Knowledge search for reviews on the topic "conducting polymer" and found the following highly-cited articles:

• 2186 citations: Heeger, A. J.; Kivelson, S.; Schrieffer, J. R.; Su, W. -P. (1988). "Solitons in conducting polymers". Rev. Mod. Phys. 60: 781–850. doi:10.1103/RevModPhys.60.781.
• 1808 citations: Roncali, J. (1992). "Conjugated poly(thiophenes): synthesis, functionalization, and applications". Chem. Rev. 92: 711–738. doi:10.1021/cr00012a009.
  • "The modern era of CPs began at the end of the 1970s when Heeger and MacDiarmid discovered that polyacetylene, ((CH)_x), synthesized by Shirakawa's method, could undergo a 12 order of magnitude increase of conductivity upon charge-transfer oxidative doping."

There are probably more good ones out there. I will keep looking. --Ben (talk) 19:03, 21 May 2012 (UTC)

New (?) Field-Induced Polymer Electroluminescence Lighting Technology

I think WIkipedia may need an article on "field-induced polymer electroluminescence" lighting technology, somehow distinct from OLEDs:

http://www.bbc.co.uk/news/science-environment-20553143

And some people lurking around this article seem to be the sorts who could figure it what it should say.

There are almost no Google results for "field-induced polymer electroluminescence", more for "polymer electroluminescence".

What I'm wondering in particular is whether it produces a continuous spectrum (like the Sun, fire, incandescents) or specific R-G-B wavelengths to form a simulated composite white.

All yours -- I'm a "creative type".

Thanks.