/pdf/aryl-aryl-bond-formation-one-century-after-the-discovery-of-1jdyxlkwix.pdf

Aryl-aryl bond formation one century after the discovery of the Ullmann reaction.

Synthetic Principles for Bandgap Control in Linear pi-Conjugated Systems.

Electrochemical energy storage systems (batteries) have a tremendous role in technical applications In this review the authors examine the prospects of electroactive polymers in view of the properties required for such batteries Conducting organic polymers are considered here in the light of their rugged chemical environment: organic solvents, acids, and alkalis The goal of the present article is to provide, first of all in tabular form, a survey of electroactive polymers in view of potential applications in rechargeable batteries It reviews the preparative methods and the electrochemical performance of polymers as rechargeable battery electrodes The theoretical values of specific charge of the polymers are comparable to those of metal oxide electrodes, but are not as high as those of most of the metal electrodes normally used in batteries Therefore, it is an advantage in conventional battery designs to use the conducting polymer as a positive electrode material in combination with a negative electrode such as Li, Na, Mg, Zn, MeH{sub x}, etc 504 refs

Electrochemically Active Polymers for Rechargeable Batteries.

Polyaniline: a polymer with many interesting intrinsic redox states

This article summarises the industrial applications of poly-(3,4-ethylenedioxythiophene)
				(PEDT, PEDOT). The basic chemical and physical properties of PEDT are discussed to outline the fundamentals which lead to PEDT as a highly valuable electric and electronic material. PEDT applications are reviewed depending on the two different ways of preparation: in situ polymerisation of the monomer, usually carried out by the user, and applying the prefabricated polymer in the form of its water-based complex with poly(styrene sulfonic acid). Several applications like antistatic coatings, cathodes in capacitors, through-hole plating, OLED's, OFET's, photovoltaics, and electrochromic applications are discussed in detail.

Scientific importance, properties and growing applications of poly(3,4-ethylenedioxythiophene)

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(OC4H9)4–Al(C2H5)3 system (Al/Ti = 3–4) and the critical concentration was 3 mmole/l. of Ti(OC4H9)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 A in width and of indefinite length.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/pola.1996.854

Simultaneous polymerization and formation of polyacetylene film on the surface of concentrated soluble Ziegler-type catalyst solution

The infrared spectra of poly(acetylene), poly(acetylene-d2), copoly(acety+acetylene-d2), and copoly(acetylene+acetylene-d1+acetylene-d2) prepared by the Ti(OC4H9)4–Al(C2H5)3 system over a wide temperature range (ca. −100 to 180°C) are reported. A tentative assignment of the observed spectra is made on the basis of model structures in which infinite planar chains of all trans, all trans–cisoid, and all cis–transoid configurations are assumed. The spectral data are best interpreted on the basis of an all cis-transoid (or an all trans-cisoid) structure for the polymers prepared at temperatures lower than −78°C, and an all trans structure for the polymers prepared at temperatures higher than 150°C.Simplified calculations of the C-H and C-D out-of-plane deformation frequencies are made for various model chains. It has been concluded from a comparison of the observed and calculated frequencies that the cis-opening of the triple bond occurs in a polymerization reaction with the Ti(OC4H9)4–Al(C2H5)3 catalyst system at low temperatures.

/pdf/infrared-spectra-of-poly-acetylene-483bfmefnm.pdf

Infrared Spectra of Poly(acetylene)

Thermal cis-trans isomerization and decomposition of polyacetylene film prepared with a Ti(OC4H9)4–Al(C2H5)3 (Al/Ti = 4) system were investigated under inert gas or in vacuum by means of thermal analysis and infrared spectroscopy. Thermograms of differential thermal analysis of cis-polyacetylene revealed the existence of two exothermic peaks at 145 and 325°C and one endothermic peak at 420°C which were assigned to cis-trans isomerization, hydrogen migration accompanied with crosslinking reaction, and thermal decomposition, respectively. The isomerization was followed by infrared spectroscopy over the temperature range 75–115°C. The reaction did not obey simple kinetics. The apparent activation energy for the cis-trans isomerization was 17.0 kcal/mole for the polymer containing 88% cis configuration and increased with increasing trans content up to 38.8 kcal/mole for 80% trans content.

Thermal cis–trans isomerization and decomposition of polyacetylene

/pdf/raman-scattering-and-electronic-spectra-of-poly-acetylene-ruazfv9ztt.pdf

Raman Scattering and Electronic Spectra of Poly(acetylene)

The electrical conductivity of crystalline polyacetylene films having various cis-trans compositions was measured. The resistivity and the energy gap of a 92,5% trans polymer were 1,01·104Ω·cm and 0,56 eV, respectively, whereas the values of a 20,0% trans polymer were 2,35·108Ω·cm and 0,93 eV, respectively. These differences are discussed in terms of the effective conjugation length estimated from visible spectra and ESR measurements, and the spacing between molecular planes obtained by x-ray diffraction measurements.

Hideki Shirakawa

Papers

Simultaneous polymerization and formation of polyacetylene film on the surface of concentrated soluble Ziegler-type catalyst solution

Infrared Spectra of Poly(acetylene)

Thermal cis–trans isomerization and decomposition of polyacetylene

Raman Scattering and Electronic Spectra of Poly(acetylene)

Electrical properties of polyacetylene with various cis‐trans compositions