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The kinetics of the electrosynthesis of this polyconjugated material was followed by ex situ ultramicrogravimetry. The electrochemical reduction of the film in aqueous solution gives an insoluble film of the reduced material. On this way both, oxidized and reduced states of the material, are available as solid films. The flow of an anodic current through a solution of reduced material gives a faradaic electrodeposition of the oxidized state. The process was also followed by microgravimetric determination of the deposited dry films. Checking different electrolyte productivities similar to those obtained during electrodissolution were obtained. The resulting films were also soluble in organic solvents. The influence of the different chemical and electrical variables in the electrogeneration, electrodissolution and electrodeposition processes were studied. The final aim of this paper is to find new ways of processability for conducting polymers, which can be applied to manufacture new actuators and artificial muscles.

EXPERIMENTAL The availability of important quantities of monomer was possible by improving the method of synthesis described by Wynberg and Matselaar14. The intermediate 1,4-di-(2thienyl)-1,4-butanedione was kept under reflux with ammonium acetate, glacial acetic acid and acetic anhidric overnight under nitrogen atmosphere. The reaction mixture was then poured into 250 ml of distilled water and the resulting dark-green solid was chromatographed through silica gel columns using a mixture of dichloromethane and hexane (3:2) for elution. A 75% of SNS, as pale yellow crystals, was obtained. The synthesized monomer, several grams can be obtained every time, was stored under nitrogen. Acetonitrile (Lab Scan, HPLC grade) was used as solvent in the electrochemical experiments. Lithium perchlorate (Aldrich, A.C.S. reagent), tetraethyl-ammonium perchlorate (TEAC10 4 ), tetrabutyl-ammonium perchlorate (TBACIO4) and thetrahexyl-ammonium perchlorate (THAClO 4) (Fluka purum reagent) were dried in an oven at 80 'C before use. All the electrochemical studies were performed in a one-compartment thermostat threeelectrode cell. The working and counter electrodes were two platinum sheets of 1 and 2 cm 2 of surface area, respectively. Both electrodes were immersed in sulfochromic mixture and rinsed with water and acetonitrile before each electrogeneration or electrodeposition. The reference electrode was an Ag/AgCl (3MKCI) electrode. Chronoamperometric, chonopotentiometric and voltammetric measurements were carried out using a PAR 273 potentiostat-galvanostat connected to a personal computer and controlled through a PAR M270 program. Each solution was deoxygenated by nitrogen bubbling, presaturated with acetonitrile, for 20 min before each experiment. The polymer weight was obtained by "ex situ" microgravimetry. Each film was dried in hot air, rinsed several times in acetonitrile, dried again and weighed until constant weight. Weights of electrodes or polymer films were determined using a Sartorious 4504 MPS ultramicrobalan