Talk:Conductive polymer

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 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 unteil 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 "conduciitve polymers" are far from being well understood, and that what is "accepted" does by far not explain the experimental facts. —Preceding unsigned comment added by 183.37.155.38 (talk) 08:12, 15 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)

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)

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)

Lead section

The lead section of this article is too big and too complex. I don't know anything about Conductive polymers, so can someone who does move the data into the article body? Josh Parris ✉ 06:19, 28 July 2005 (UTC)

• Not only the lead section but the whole thing is so complex. Can someone please translate this interesting article with more basic concepts. Thank you. --Quinlan Vos 00:15, 18 January 2006 (UTC)

Recent changes

1) Historically, the linear-chain polymer "blacks" have been called melanins. Some fungal melanins are even pure polyacetylene.

2) If this were a "vanity" article, is it for Weiss's group. In 1963, they reported [2] a conductivity as low as 1 S/cm in oxidized, iodine-doped polypyrrole (verses the prize-winners oxidized, iodine-doped polyacetylene). Mcginness was merely the last (and most visible, with papers in Science and and a news article in Nature) person to show high conductivity in this class of organic polymers before the Nobel winners grabbed the credit. And this was only incidental. Pproctor 01:47, 17 October 2006 (UTC)

Well this should not be a vanity article for any group, IMHO. WE is not an effective forum for settling past injustices, real or perceived. A very useful service for readers of WE would be to summarize the science, invite others to contribute..And let the McGinness thing go - he is forgotten. So were lots of scientists.--Smokefoot 02:07, 17 October 2006 (UTC)

I'm just trying to provide a brief history, not give anybody a puff. The fact that Weiss et al anticipated in detail the Nobel winners is an important part of this history. Read the respective papers (link above), if you question this (er) convergence. BTW, the Jan Hendrik Schön science fraud incident also involved conductive polymers. McGinness' work a decade later merely reinforces the point that conductive polymers were discovered several times and that the history is messy. Unfortunatly, you seem to have read other stuff into this. Pproctor 02:46, 17 October 2006 (UTC)

but based on your link in this article (itself a curious inclusion) [3], you are partner and coauthor with McGinness "JOHN MCGINNESS, PETER CORRY, PETER PROCTOR Physics Department, University of Texas Cancer Center, M. D. Anderson Hospital and Tumor Institute, Houston 77025" which implies that you lack NPOV. Also you are editing articles by inserting repeated reference to your own publications. But I can see from your talk page that others have issues with your perspectives.--Smokefoot 04:17, 17 October 2006 (UTC)

It is true that before I figured out how things really work here, I crossed a clique by attempting to add some NPOV to the Raymond Damadian biography. Mostly, because I was there and really knew what went on. Same as this one. Interestingly, my main hassler User:DuncHarris seems to have been banned. Hopefully the fuss I raised contributed. Wikipedia is now actively cultivating experts, possibly because of the pending competiton from Sanger's new startup.

WP:NOR sez:

• Citing oneself== "No original research" does not prohibit experts on a specific topic from adding their knowledge to Wikipedia. It does, however, prohibit expert editors from drawing on their personal and direct knowledge if such knowledge is unverifiable. Wikipedia welcomes the contributions of experts, as long as these contributions come from verifiable (i.e. published) sources. Thus, if an editor has published the results of his or her research elsewhere, in a reputable publication, then the editor may cite that source while writing in the third person and complying with our NPOV policy. We further hope expert editors will draw on their knowledge of other published sources to enrich our articles. While specialists do not occupy a privileged position within Wikipedia, they are often familiar with and have access to a wider range of verifiable sources and can thus be of special assistance in verifying or citing sources...."

As you note, we were the second people to discover high conductivity in a linear backbone polymer. Not contenders at all, at least for high conductivity per se. "Close only counts in horse-shoes and handgrenades"--and our decade later is hardly "close". I fact, it is only matched by the "Prize"- winners 14 years later. But it does give mucho authority to pronounce who really has priority claims, naturally, supported by the literature-- This is Weiss' group. I was a grad student at the time and haven't been involved here for years. Now a physician, thank goodness. All these shenangans are too much.

But I do retain an intellectual interest. So I feel quite qualified to discuss the history dispassionately. As noted above, "Experts" are specifically valued here because we know the literature. We can cite our own publications at arms length. I do so mainly to give historical credit where it really belongs. This is with Weiss and his coworkers, the Australians who discovered high conductivity in a linear backbone polymer 10 years before we did and 13 years before the eventual Nobel winners. All NPOV, NOR, and with appropriate cites. etc. If you object to these cites, which speak for themselves, please tell us all how and why.

Interestingly, the original cite to Weiss et al was provided by an anonymous poster whose IP number traces to the University of Woolagong, which just happens to be a big Australian center of research on conductive polymers. Allegedly, (I cannot provide a printed cite so it is OR) the Aussies were a bit put out by the Nobel. Don't blame them myself. Pproctor 05:33, 17 October 2006 (UTC)

Another early conductive polymer

Just put another cite to a highly-conductive polymer from the late 1960's. I note that this moves us from the second discoverers of a highly conductive organic polymer to the third in line. Also, I cite a review of the early history which makes the point that in this area "There is Nothing New Under the Sun". The history of discovery is important guys...Pproctor (talk) 04:58, 2 June 2009 (UTC)

Restored some of the material deleted. Again, I can back up all muy stuff with citations, etc. . Please do not remove these without having somethng equivalent to substitute. Otherwise, you are committing the sin of NOR.Pproctor (talk) 03:39, 4 June 2009 (UTC)

Just restored the reference to Hush's review of the history of conductive polymers. It also is a chapter in a book on conductive polymers. Why anyone would want to remove such a cite I do not understand.Pproctor (talk) 05:16, 9 June 2009 (UTC)

Recent Revisions

IP # 66.134.161.210 says:

"Despite their early discovery, the synthetic mechanism, appropriate structure, and reasons for conductivity were largely incorrect and not followed up with further work."

Actually, Balto et al published (IIRC) 6-7 papers and the odd patent or two. Their work extended over several years and appears quite substantial to me. Their main scientific sin was publishing too early, before the scientific world was receptive. Nobody picked up on it. Likely, the funding eventually dried up, their department chairman started questioning what they were doing, etc.

By your criteria, Cupernicus or Gregor Medel don't deserve credit for their discoveries either. As for "wrong mechanism", this was 1964. Their work cannot be judged by the standards of 4 decades later.

E.g., Neville Mott's work on conduction in amorphous semiconductors had not been extensively-disseminated. The mechanism for conduction in disorder polymers had to await John McGinness' 1972 paper in Science, applying Mott's model to conductive polymers.

"The reactions required heating several elements and compounds for solid state reaction that make determination of the chemical structures difficult even with todays technology. This extensive work was not recognized."

Arguable, but irrelevant. Balto et al purposefully made an iodine-doped conductive polyactylene derivative 13 years before Heeger et al stumbled upon another one by accident. BTW, Heeger et al used some of the same synthesis techniques, particularly in their patents.

"In retrospect these changes in current are probably the result of changes in the oxidation state of the polymer they were exploring. These characteristics are often seen in measuring cyclic voltammograms of conducting polymers, where they typically have one conductive oxidation state that requires a counterion that acts as a dopant.

True, "doping" in conductive polymers is often (generally?) concerned with changes in the oxidation state of the polymer. This is one reason organic polymers in a protonic solvent are often "self-doping".

"The exact polymer they used is likely unclear."

Compared to what ? Actually, because of its medical relevance, much early work on conductive polyacetylene derivatives was done under the "melanin" rubrick. Later workers reinvinted the wheel without realizing it. The structure of melanins (including DOPA melanin ) was well-characterized in the 1950's and '60's, especially by Roberto Nicolaus and his coworkers in Naples. The same is true of (e.g.) polyacetylene itself, well-known as the "melanin" of certain fungi. Remember, all polyacetylenes are melanins and vice versa.

E.g., R. Nicolaus: "The most simple melanin can be considered the acetylene-black from which it is possible to derive all the others..... Substitution does not qualitatively influence the physical properties like conductivity, colour, EPR, which remain unaltered." from The Nature of Animal Blacks ( "acetylene-black" = polyacetylene).

"Subsequently, Alan J. Heeger, Alan MacDiarmid and Hideki Shirakawa reported high conductivity in iodine-doped polyacetylene. This discovery was the first of several more comprehensive studies that included the structure, doping and understanding of the conduction mechanism. Though they may have not been the first to find conductivity in organic materials, this work was the first that clearly identified the reasons, the true structures and physics behind the conduction.

First ?-- not so. E.g. well before Heeger et al, John McGinness' 1972 paper in the journal Science" applied Mott's et al's work on conduction in disordered materials to explain the unusual semiconductive properties of melanin and similar polyacetylene derivatives. As for "doping" everyone used that and on purpose. Balto et al even used Iodine, the same dopant that Heeger et al used. Likewise, McGinness et al used (e.g.) diethylamine as a dopant. In a fascinating example of convergance, Heeger et al subsequently used (IIRC) dimethylamine.

BTW, McGinness purposefully searched for switching behavior based upon his 1972 model for conduction in such materials. Not surprisingly, he found it.

Again, you should not judge these reports by the state of the art 40 years later or even a decade later. True. Heeger et al figured out the conduction mechanism in the special case of pure polyacetylene. But McGinness' application of Mott's et als' model is the generally-applicable mechanism for this whole class of compounds.

"This along with the vast bodies of work generated by these leaders in their field earned them the 2000 Nobel prize in Chemistry "For the discovery and development of conductive polymers.""

There is now general agreement that Heeger et al did NOT discover conductive organic polymers. In fact, counting high conductivity polymers, they were apparently no better than fourth in line. If we count Blois work showing conductivity (but not high conductivity) in melanins, they were no better than fifth. The Nobel committee blew it. Hopefully one day they will acknowledge this.

Similarly, Nobel's will specifies that "the prize" goes to the person "who shall have discovered", not to later workers who publish scads of papers. The Nobel foundation generally carefully adheres to this rule.

Clearly, the Noble committee did not know the true history of discovery. Otherwise, they would have cited the previous discoverers. They would also have carefully avoided giving Heeger et al credit for the "discovery" of highly-conductive polymers per se and left it at "development" or spun it some other way. Nobel committees are generally very careful about awarding false discovery credit. They generally work the wording to avoid this in ambiguous or controversial cases, such as the prize for MRI.

"Some debate whether this was appropriate since they may not have been the first to identify the existence of conducting polymers.

"May not have been the first" ? Clearly, "were not" the first. Fourth in line at best, arguably even fifth. Even further down if you count photoconductivity. Thus (e.g.) Melanins (e.g.) were shown to be conductive in the 1960's by Marsden Blois and coworkers. In fact, McGinness came up with his 1972 general model to explain such anomalies as a rise in conductivity with voltage, rather the the expected opposite.

"This may be warranted, but had the body of work of these Nobel prize winners not commenced, the development of conducting polymers may have been delayed decades more."

Just the opposite. Had Heeger et al properly acknowledged earlier discoveries, much time and repeat effort would have been saved. By requiring things to be rediscovered, "Citation amnesia" wastes resources.Pproctor (talk) 01:53, 10 August 2009 (UTC)

It is not appropriate to delete the cited reason for the Nobel award just because you happen to disagree with it. --SarekOfVulcan (talk) 14:34, 10 August 2009 (UTC)

The article will remain suspect until PProctor desists from editing

Readers and potential editors should be aware that this article is closely policed by User:Pproctor, embittered student of a John McGinness (Wiki-article and one-time nominee for deletion for non-notability, virtually single-authored by PProctor). McGinness is not mentioned in the three published Nobel presentations by Heeger, by Shirakawa, nor by Alan MacDiarmid.[4]. Proctor also emphasizes the contributions published in Aust J. Chem in an apparent ploy to detract from the contributions from the Nobel Prize winners. These papers by Weiss et al are also not mentioned by Heeger, Shirakawa, or Alan MacDiarmid. So edit at your own risk, but do not expect a modern useful article until an set of objective, knowledgeable editors become involved. What PProctor lacks in objectivity and scientific standards, he makes up for in persistence.--Smokefoot (talk) 20:21, 9 August 2009 (UTC)

Having a bad day, eh ? The shrinks (my daughter is one) tell us that us that When somebody makes claims about another person's motivations on the basis of no evidence, they are often merely projecting their own internal turmoil.

Anyway, as I make clear, we were 14 years too late to claim priority for discovering highly conductive polymers. So this is a straw argument. BTW, the reference to Balto et al's early work was provided by someone else. I am merly keeping the likes of you from removing it. The rule of thumb is "don't remove other people references to substitute your personal opinion". Instead, provide your own cites, if you can.

As for your "appeal to authority"-- It is true that Heeger et al did not cite previous publications reporting highly-conductive polymers. As my cites show, this has been pointed out by others. The title of one history is even "Nothing New under the sun.." Bit of a scandal, really. If this omission was on purpose, it constitutes "citation amnesia", aka, "citation plagarism" and is a very serious offense. But all this is a secondary matter. The history I give is the history and all well documented.Pproctor (talk) 04:34, 11 August 2009 (UTC)

If you're going to accuse a Nobel winner of plagiarism, I would suggest there are much better places to do it than Wikipedia. Wikipedia is WP:NOT a forum for "setting the record straight". --SarekOfVulcan (talk) 19:12, 11 August 2009 (UTC)

Note I say "if the omission was purposeful". "Citation amnesia" is not plagarism per se and may be quite inadvertant. In fact, in the links I give many researchers plead guilty to being a little careless about citations sometimes. Done it myself, but correct it ASAP. As for "setting the record straight", my intent is to give the history of this field as accurately and impartially as possible. Note that this often involves minimizing our own role, while maximizing that of other researchers. YMMV, naturally.Pproctor (talk) 20:37, 11 August 2009 (UTC)

Most recent changes

In the interest of NPOV, I have previously carefully-avoided more than a simple list of early researchers and their work. Similarly, I have given cites to book chapters covering the history of conductive polymers. This was without commentary on Heeger et al's Nobel prize, a controversial area. I feel the facts speak for themselves.

But this issue having been raised by other editors, I have replied to it, providing even more cites. Imagine (e.g.) asserting that the discovery of semiconduction in melanins is "recent". Again this is in the interest of NPOV.Pproctor (talk) 15:14, 11 August 2009 (UTC)

Melanins, let's just drop that

PProctor, I realize from the titles of your papers you are citing that you consider melanins to be a member of the class of conducting polymers, but that inclusion is highly unconventional even though it serves your interest in self-citation and your idea of "setting the record straight." The usual definition of an organic metal is of a material prepared by polymerization of well-defined monomers. The materials scientist has control at the monomer level. If you could agree to drop the melanin theme, the article would be significantly advanced and tempers would calm If you look at a modern materials science text or reviews on organic metals, they are focused on polythiophenes and polypyrroles and polyanilines. They cite the early work on perylene and then Shirakawa's polyacetylene. There is a huge emphasis on band gap engineering by selection of appropriate heterocycles. But the melanin theme is, I feel, a ruse as well a head-scratcher to most readers who must be thinking wha? when they read about melanins in an article supposed to be focused on modern materials. The melanin theme reads like attempt to detract from the Nobel-earning work that merged aspects of modern polymerization chemistry and physics.--Smokefoot (talk) 13:43, 12 August 2009 (UTC)

Unconventional to whom ? BTW, do you have a reference for this opinion. Otherwise, it is simply unsubstantiated OR and denialism. You must abide by the rules too, as I carefully have.

The melanins are all conductive polyacetylene derivatives (i.e, composed of polyacetylene, polypyrrole, and polyaniline in various combinations ) and vice versa. I have provided a wide assortment of references to this effect. I suggest you read Roberto Nicolaus' website [5], where he gives an exaustive review of the chemistry, structure, and physics of these compounds. BTW, my friend Dr. Nicolaus was director of the Accademia Pontaniana, the oldest still-existing research institution in the world and ex-officio a sometime nobel nominator.

Further, because of their medical import, much of the earliest work on the structure and physics of acetylene-type conductive and semiconductive polymers was done in their "melanin" guise. E.g., that much of this early work was done in southern Italy is an artifact of the high incidence of Melanoma there.

Interestingly, band gap engineering in conductive polymers originated with John McGinness' 1972 paper [6] in Science, This paper is tellingly-entitled "Mobility gaps, a Mechanism for Band Gaps in Melanin". Look it up. From this model, Dr McGinness "engineered" his bistable switch.

The physics of melanins field was hot while the rest of conductive polymers was essentially moribund. Deny the melanin work, and you cut off a substantial part of the history of conductive polymers.

Hell, I'll be happy to post a copy of the Smithsonian Institution "Deed of Gift" where they list Dr. McGinness' bistable switch as "an early organic semiconductor". Can't get any more authoritative than that. This is all getting very tiresome. Everytime I come over here and run into this kind of arbitrary behavior. I understand why experts tend to stay away. See Larry Sanger.Pproctor (talk) 18:13, 12 August 2009 (UTC)

Accusing other editors of "denying reality" is not following the rules, so you just lost the right to claim that. Also, posting the "Deed of Gift" proves nothing, considering the document is submitted with the gift, not given by the SI in receipt for one. Nice try. --SarekOfVulcan (talk) 19:00, 12 August 2009 (UTC)

Lets see, My copy of the Smithsonian Deed of Gift says # 27625, indicating that the Smithsonian has not taken a lot of stuff, considering. Then it says "Donor's Copy", followed by a bunch of "By these presents...' boilerplate. Then the Deed of Gift describes the item in bold as "Organic Semiconductor (I/O) 1973". I suppose I ought to post it somewhere.

The "gadget" is now in the "Smithsonian chips" collection of early electronic devices. As I note, this is arguably the first example of purposeful "bandgap engineering" in conductive polymers, since to get it to really switch well, ya gotta dope it with (IIRC) diethylamine, not a very physiological substance. BTW, Dr McGinness is a real honest-to-god solid state physicist, with a PhD from Rice, no less.

By denialism I mean that you seem prepared to deny the majority of the well-documented early history of the physics of conductive polymers. And don't forget I also asserted "Original research", since you seem unprepared to back up your opinion with any references or whatever. I also notice that you do not deign to reply to my other points.

Actually, that much early research on conductive polyacetylenes bears the "melanin" rubrick is purely an artifact. Because of its medical importance, funding agencies would pay for reseach on the physics of "melanin", when they wouldn't pay anything for the same research on "conductive polyacetylenes". Fellas gotta eat. Pproctor (talk) 19:52, 12 August 2009 (UTC)

Addendum: Until recently, it was much easier to get papers into the likes of Science or Nature if they had "melanin" and not "conductive polyacetylene" in the title. Pproctor (talk) 20:17, 12 August 2009 (UTC)

http://smithsonianchips.si.edu/proctor/index.htm - it credits the "organic semiconductor" text pretty clearly to you. --SarekOfVulcan (talk) 19:58, 12 August 2009 (UTC)

Actually, I submitted it under "a melanin (polyacetylenes) bistable switch." The Smithsonian added the "Organic Semiconductor (I/O) 1973" bit as part of their induction (I/O) process. But the point is that nobody seems to have objected to either of these characterizations. Pproctor (talk) 20:24, 12 August 2009 (UTC)

Melanin count

As of Aug 14, We're up to seven mentions of melanins. This term remains very, very obscure term, and one that is absent in the vocabulary of organic materials as indicated by the search of major reviews and text books. PProctor apparently seeks to emphasize melanins to validate his contributions, which are so under-recognized as not to be mentioned in the Nobel citations or modern reviews and texts. This response is understandable and is largely tolerated within Wikipedia, but an emphasis on melanins is a disservice to readers. In fact the melanin aspect highlights the triumph of Nobelists Heeger, Shirakawa, and MacDiarmid, who used well defined monomers and well defeined polymerization stategies (electropolymerization, cross coupling, and Ziegler Natta polymerization). I will try to reedit to more strongly emphasize this aspect. I am sorry to see such a strong conflict between the vain needs of Proctor et al trumping what any scholar can see in the modern literature. --Smokefoot (talk) 13:20, 14 August 2009 (UTC)

"vain needs" -- easy on the personal attacks there, please. --SarekOfVulcan (talk) 14:55, 14 August 2009 (UTC)

I apologize for this offensive term.--Smokefoot (talk) 17:15, 14 August 2009 (UTC)

Melanin and McGinness

Again, my aim is to rebalance the article by placing the emphasis on mainstream concepts. My continuing concern has been the undue emphasis on melanin and this person John McGinness. I consulted what appears to be a major monograph on conducting polymers, “Conducting Polymers, A New Era in Electrochemistry” Springer, 2008, Berlin, Heidelberg. doi:10.1007/978-3-540-75930-0. Here are my findings.

• Chapter 1: "Introduction" (3 pages): no mention: melanin, John McGinness
• Chapter 2: "Classification of Electrochemically Active Polymers" (57 pages): no mention: melanin, John McGinness
• Chapter 8 “Historical Background (Or: There Is Nothing New Under the Sun)” (2.5 pages): no mention: melanin, John McGinness

--Smokefoot (talk) 17:56, 14 August 2009 (UTC)

Here is what Hush says about the McGinness paper: "Also in 1974 came the first experimental demonstration of an operating molecular electronic device that functions along the lines of the biopolymer conduction ideas of Szent-Gyorgi. This advance was made by McGinness, Corry, and Proctor who examined conduction through artificial and biological melanin oligomers. They observed semiconductor properties of the organic material and demonstrated strong negative differential resistance, a hallmark of modern advances in molecular electronics {emphasis-added).58 Like many early advances, the significance of the results obtained was not fully appreciated until decades later... emphasis-added. ".

BTW, Dr Inselt, the author of the "Nothing New Under the Sun" article, tells me his purpose was to give proper discovery credit for highly-conductive polymers. Read the article and it will become obvious that he doesn't think it was Heeger et al.

Also see www.organicsemiconductors.com and the smithsonian chips list of significant discoveries in semiconductor physics. This states: "The Chip Collection is a continuing collection work-in-progress concerning a small part of the permanent collection of the Division of Information Technology & Society's Electricity Collections." This includes items like the original SCSI interface, germanium and silicon crystals from TI in 1950, etc. About half way down is the gadget in question. There is not a single other organic polymer-based device in this rather select assortment. Go argue with them whether it is significant or not.

I have deliberately refrained from citing these previously. A quick reading should show that my effort here is concentrated on work that anteceded ours. All this has done is move us down the priority list. This is hardly a thing to do if "vain needs" are involved, other than the satisfaction of doing a workman-like job of recounting the history and not learning from the devil. Besides, I gave up all of this decades ago for greener pastures. History of discovery is now my interest.

As for Heeger et al's work, there were uncited antecedents for most else they did, e.g., the importance of "mobility gaps", electron-phonon-coupling, tunnelling, and and hopping with respct to conductive polymers had already been published. Mostly likely, they did first work out the details of conduction in pure polyacetylene. This is a special case because it has long-range order, pretty much absent from other conductive polymners. In one or two of their patents (but not their papers) they cited DeSurville et al. Otherwise, nothing.

Anyway, Whatever the merits of the "development" part of the Nobel award, the "discovery" part was clearly misplaced. Because Nobel's will specifies that the award goes for a "discovery" and to the person who "shall have discovered", The Noble committees generally avoid such gross mistakes. From which we can reasonably conclude that the Chemistry committee did not know of the prior art.

As for "melanins". these are hardly obscure in the real world. Just ask anybody with melanoma or Parkinson's disease. This is why the physics of conductive polymers in their melanin guise was researched early and well. Similarly, ever seen a deaf white Kitty or someone with Waardenbergs syndrome.Pproctor (talk) 18:44, 14 August 2009 (UTC)

Melanin and Parkinson's disease

For an example of how the physical properties of melanins were early connected with (e.g.) Parkinsons disease, See: . and . This work led Dr Cotzias and his co-workers to develop Levodopa treatment , still the most important treatment for Parkinson's disease.Pproctor (talk) 19:42, 14 August 2009 (UTC)

Now we are getting somewhere. Agreed: melanins are not obscure materials per se. But in articles about electronic materials, melanins are so obscure that they go unmentions in three Nobel lectures and the monograph on Conducting Polymers. Emphasizing melanins is a form of original research. --Smokefoot (talk) 22:36, 14 August 2009 (UTC)

Uh, the Nobel lectures not only avoided melanins, they avoided mentioning the other relevant prior art too. This includes two previous discoveries of highly-conductive polymers. One of these at least (Balto et al) used a rather similar material (polypyrrole) and an identical dopant (Iodine). What were they going to do, say "Uh, we didn't really discover conductive polymers ? Remember, the prize was for "discovery and development". See "citation amnesia".

BTW, as have others, I once confronted Dr. Heeger on this at a meeting. His defense was "Well, they ignored the "charge-transfer complex workers too". Which rather begs the question.

Anyway, this omission has been corrected in subsequent reviews of the history of conductive organic polymers, such as by Hush and Inselt and on the Smithsonian Chips website. .Pproctor (talk) 14 August 2009 (UTC)

I am sympathetic about the lack of acknowledgement of prior art by Heeger and others. The practice is rampant, unjust, and hypocritical, but Wikipedia is not the place to redress these concerns (except for Nobel Prize controversies, where you have contributed). Getting back to my gripe, melanins are not mentioned in any mainstream books and reviews, so they ought to be less emphasized in the article. The omissions of melanin work by mainstream reviews and books is probably not intended as slights or suppression, but reflects a focus on molecularly well defined precursors. As you indicate, the oversight may reflect a narrow appreciation of scope by workers in the field. Agreed, but the area is what it is, and you and I are not here to set the record straight or redefine the field. --Smokefoot (talk) 19:33, 15 August 2009 (UTC)

All this happened nine years ago and has since been amply corrected in the literature. See, e.g. Hush and Inselt. Not to mention the Smithsonian. So "redress" is not an issue. BTW, Dr. Inselt tells me he did not know of us and only vaguely knew of Balto.

A rule of thumb in science is that the grunt literature searches generally are done by some post-doc with only a vague knowledge or concern about the history and usually only go back five years or so. Further, most publications have limitations on citations. so older work often does not get cited. See this article [7] in "The Scientist" on the commmon causes of citation amnesia. It is very common. A sample quote:

"Indeed, the vast majority of the survey's roughly 550 respondents -- 85% -- said that citation amnesia in the life sciences literature is an already-serious or potentially serious problem. A full 72% of respondents said their own work had been regularly or frequently ignored in the citations list of subsequent publications. Respondents' explanations of the causes range from maliciousness to laziness."

Anyway, a lack of knowledge of some workers in this field of its past history produced partially by the citation amnesia of certain major players is no reason for dismissing that history, particularly when it is abundantly documented. Historically, most work on the physics of conductive polyacetylenes was done under the "melanin" rubrick. Because of its medical applications, such work was both fundable and publishable in major journals such as Science and Nature. Dr. McGinness' 1974 Science paper (the one now in the Smithsonian) was also the subject of a 'Nature' "News and views" article. He similarly published several papers in the latter journal. This was hot stuff in the 1970's. E.g., see the letter to Dr. Mcginness from Neville Mott.

In contrast, in "non-medical" research on conductive polyacetylenes, there were a few researchers such as Bolto et al (who really first reported highly-conductive polymers), but nobody was much interested. so, after a brief flurry of papers, such work repeatedly died out.

Heeger 'et al' were lucky in their timing in that people who were aware of the real history had pretty much dropped out. Einstein (?) allegedly once said that "The secret of genius is hiding your sources". BTW, because his organic polymer battery patents overlapped theirs, Dr. Mcginness sent Heeger 'et al' a copy of his papers in about 1981. I did so again in 1986, when one of them published an article in Scientific American. No answer..Pproctor (talk) 22:14, 15 August 2009 (UTC)

Smithsonian chips

I refer everyone to the homepage of the National Museum of American History's "Smithsonian chips" page [8].

This states: "The Chip Collection is a continuing collection work-in-progress concerning a small part of the permanent collection of the Division of Information Technology & Society's Electricity Collections."

This includes items like the original SCSI interface, germanium and silicon crystals from TI in 1950, etc. About half way down is the gadget in question. There is not a single other organic polymer-based device in this rather select assortment. Go argue with them whether Melanin is significant or not in the history of conductive polymers.Pproctor (talk) 20:13, 13 August 2009 (UTC)

Addendum: drjem3 put a link to the "Smithsonian Chips" page that contains the gadget in question. This got removed on the basis that it was redundant with the Smithsonian link. No big deal. For various reasons, I had refrained from this myself.

But someone who has not been there might not realize that the Smithsonian is a very big place, incorporating numerous museums, research institutes, etc... Any one of these can be a big as a major musuem in (say) Europe. So, a link directly to the "Smithsonian Chips" (technically part of the American Museum of History) site might be appropriate.Pproctor (talk) 20:30, 13 August 2009 (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)