Shirakawa polyacetylene

Figure 1 Typical diffraction patterns from undoped CPs (a) frms-polyacetylene, Shirakawa-type, from Ref. 34 (b) polyaniline, emeraldine salt form II, from Ref. 24 (c) polythiophene, from Ref. 22.

Polyacetylenes. The first report of the synthesis of a strong, flexible, free-standing film of the simplest conjugated polymer, polyacetylene [26571-64-2] (CH), was made in 1974 (16). The process, known as the Shirakawa technique, involves polymerization of acetylene on a thin-film coating of a heterogeneous Ziegler-Natta initiator system in a glass reactor, as shown in equation 1. 

Shirakawa, H., The discovery of polyacetylene film the dawning of an era of conducting polymers, Nobel lecture, December 8, 2000. 

Shirakawa polyacetylene, 444 Siloxanes, polymerization, 239 Size exclusion chromatography, 262-263 Solubility, specialty polymers, 256 Spacers, flexible polymer backbones, 97 Specialty polymers, polar/ionic groups, 256 Stability, polymers, 256 Storage moduli, vs. temperature behavior, 270... 

The most commonly used form of polyacetylene is produced by the Shirakawa method, which involves the direct polymerisation of acetylene gas onto a substrate at... 

Shirakawa H, Louis EJ, MacDiarmid AG, Chiang CK, Heeger AJ (1977) Synthesis of electrically conducting organic polymers halogen derivatives of polyacetylene, (CH)X. J Chem Soc Chem Commun 578-580... 

Chiang CK, Fincher CR Jr, Park YW, Fleeger AJ, Shirakawa H, Louis EJ (1977) Electrical conductivity in doped polyacetylene. Phys Rev Lett 39 1098-1101, erratum (1978) Phys Rev Lett 40 1472... 

Electrically insulating films of polyacetylene, doped with iodine and sodium, became semiconductive (Shirakawa, MacDiarmid, Heeger, 1976). 

CK Chiang, CR Fincher, YW Park, AJ Fleeger, FI Shirakawa, EJ Louis, SC Gau, and AG MacDiarmid, Electrical conductivity in doped polyacetylene, Phys. Rev. Lett., 39 1098-1101, 1977. 

Poly acetylene was initially produced using Ziegler-Natta systems, which resulted in the production of what is now known as Shirakawa polyacetylene. These materials are not easily processable and are mainly fibrillar. Recently, other approaches have been taken. In the... 

Acetylene is polymerized to polyacetylene [IUPAC poly(ethene-l,2-diyl)] by Ziegler-Natta initiators such as titanium tetraisobutoxide with triethylaluminum [Ito et al., 1974 Shelburne and Baker, 1987 Shirakawa, 2001 Theophilou and Naarman, 1989]. Polymerization at... 

One of the most interesting alternatives to the Shirakawa catalyst has been the systems disclosed by Luttinger 22-23) and later elaborated by Lieser et al. 24). The tris(2-cyanoethyl)phosphine complex of nickel chloride reacts with sodium boro-hydride to produce a catalyst system capable of polymerizing acetylene in solutions in either alcohol or, quite remarkably, water. A more efficient catalyst is obtained by replacing the nickel complex with cobalt nitrate. Interest in Luttinger polyacetylene seems to have waned in the last few years. 

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