Hideki Shirakawa

When silvery films of the semiconducting polymer, trans‘polyacetylene’, (CH)x, are exposed to chlorine, bromine, or iodine vapour, uptake of halogen occurs, and the conductivity increases markedly (over seven orders of magnitude in the case of iodine) to give, depending on the extent of halogenation, silvery or silvery-black films, some of which have a remarkably high conductivity at room temperature.

Doped polyacetylene forms a new class of conducting polymers in which the electrical conductivity can be systematically and continuously varied over a range of eleven orders of magnitude. Transport studies and far-infrared transmission measurements imply a metal-to-insulator transition at dopant concentrations near 1%.

Abstract A direct method of simultaneously polymerizing and forming acetylene monomer to produce uniformly thin films of polyacetylene was investigated in terms of catalyst system, catalyst concentration, and polymerization temperature. The best catalyst was a Ti(OC 4 H 9 ) 4 –Al(C 2 H 5 ) 3 system (Al/Ti = 3–4) and the critical concentration was 3 mmole/l. of Ti(OC 4 H 9 ) 4 . Below the critical concentration, only a solid or a powder was obtained. The configuration of the polymers obtained depends strongly upon the polymerization temperature. Thus an all‐ cis polymer was obtained at temperatures lower than −78°C, whereas an all‐ trans polymer resulted at temperatures higher than 150°C. Observations either in an electron microscope by direct transmission or in a scanning electron microscope showed that the film is composed of an accumulation of fibrils about 200–300 Å in width and of indefinite length.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of highly conducting films of derivatives of polyacetylene, (CH)xC. K. Chiang, M. A. Druy, S. C. Gau, A. J. Heeger, E. J. Louis, A. G. MacDiarmid, Y. W. Park, and H. ShirakawaCite this: J. Am. Chem. Soc. 1978, 100, 3, 1013–1015Publication Date (Print):February 1, 1978Publication History Published online1 May 2002Published inissue 1 February 1978https://pubs.acs.org/doi/10.1021/ja00471a081https://doi.org/10.1021/ja00471a081research-articleACS PublicationsRequest reuse permissionsArticle Views3558Altmetric-Citations671LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts