Electrogeneration of Conducting Poly(α-tetrathiophene). Effect of Solution Stirring and Detection of Linear Oligomers

[img]PDF - Authorized users only
Language: English
352Kb
Title:Electrogeneration of Conducting Poly(α-tetrathiophene). Effect of Solution Stirring and Detection of Linear Oligomers
Creators:
Estrany, Francesc
Oliver, Ramon
García, Esther
Gualba, Esther
Cabot, Pere-Lluís
Brillas, Enric
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 68, 7, pp. 1326-1344
Uncontrolled Keywords:Conductiong polymers, Conductivity, α-Tetrathiophene, Electropolymerization, Chronoamperometry, Cyclic voltammetry, Electrooxidations, Polythiophenes, Linear oligomers

Abstract

The anodic oxidation of α-tetrathiophene on Pt was studied in a 1.0 mM monomer solution in 0.1 M LiClO<sub>4</sub> in 45:35:20 acetonitrile/ethanol/DMF. Three consecutive oxidation peaks were detected by cyclic voltammetry, along with a cathodic peak related to the reduction of electroactive polarons formed during the first anodic process. Uniform, adherent, insoluble and black polymer films were obtained by chronoamperometry at 1.000 V <i>vs</i> Ag|AgCl corresponding to the first oxidation-polymerization process. Stirring of monomer solution promotes the production of polymer, favoring the oxidation of polymer chains with the incorporation of more doping ClO<sub>4</sub><sup>-</sup> ions and ion pairs of Li<sup>+</sup>ClO<sub>4</sub><sup>-</sup> in their monomeric units. The conductivity of the polymer obtained under stirring was three orders of magnitude higher than that synthesized from a quiescent solution. The scanning electron microscopy images also showed much more uniform films under stirring. This behavior points to the existence of less crosslinking in the polymer and the production of longer linear chains when the solution is stirred. IR analysis of these materials confirmed the formation of crosslinked chains with predominance of β-β linkages. Short linear oligomers such as the dimer, trimer and tetramer were detected in all polymers by MALDI-TOF-MS, thus showing a radical polycondensation as initial electropolymerization mechanism. A larger proportion of linear oligomers is formed under solution stirring. <p>

Title:Electrogeneration of Conducting Poly(α-tetrathiophene). Effect of Solution Stirring and Detection of Linear Oligomers
Creators:
Estrany, Francesc
Oliver, Ramon
García, Esther
Gualba, Esther
Cabot, Pere-Lluís
Brillas, Enric
Uncontrolled Keywords:Conductiong polymers, Conductivity, α-Tetrathiophene, Electropolymerization, Chronoamperometry, Cyclic voltammetry, Electrooxidations, Polythiophenes, Linear oligomers
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:68
Number:7
Page Range:pp. 1326-1344
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc20031326UNSPECIFIED
ID Code:2123
Item Type:Article
Deposited On:06 Feb 2009 17:15
Last Modified:06 Feb 2009 16:15

Citation

Estrany, Francesc; Oliver, Ramon; García, Esther; Gualba, Esther; Cabot, Pere-Lluís; Brillas, Enric (2003) Electrogeneration of Conducting Poly(α-tetrathiophene). Effect of Solution Stirring and Detection of Linear Oligomers. Collection of Czechoslovak Chemical Communications, 68 (7). pp. 1326-1344. ISSN 0010-0765

Repository Staff Only: item control page