CORREA, A. A.

MATTOSO, L. H. C.

PEREIRA, E. C.

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probe technique. A remarkable low percolation conductivity of = 10-2 S.cm1 for2.5% of the doped conducting polymer in the blend. SAXS measurements were per-formed at the small-angle scattering workstation of the Synchrotron Light NationalLaboratory (LNLS), Campinas, Brazil. Spectra were taken for ali samples for 1 hourusing a wavelength of À. = 1.7433 A, at a sample-detector distance of 885.5 mm.The SAXS curves were obtained using a dimensional position-sensitive gas detec-tor. NMR experiments were performed using a VARIAN INOVA spectrometer at 1Hfrequency of 400.0 MHz at 20 ± 2°C. A VARIAN 7-mm variable temperature probehead was used. n/2 pulse length of 4.0 ms. recycle delays of 10 s, and spin-diffusionmixing times from 0.1 to 4000 ms were used. It was observed from SAXS resultsthat the incorporation of the PANI-CSA in matrix of the SEBS, decrease its lamellarthickness morphology and broadens the interface. In addition, it was concluded di-rectly from the 1H-NMR spin-diffusion curves that the parameters not only broadensthe interface between rigid and mobile components but also decreases the mobilephase fraction.[lj Schmidt-Rohr,K.andSpiess.H.W,MultidimensionalSolid-StateNMRandPolymers.AcademicPress,London,19n~[2JMantovani,G.L.;MacOiarmid,A.G.,Mattoso,L.H.C.SyntheticMet 1997,HlINFLUENCE OF THE SUPPORTING ELECTROLYTE CONCENTRATIONON THE FORMATION OF NANOWIRES OF POLY(3-METHYL THIOPHENE) SYNTHESIZEO BY AN ELECTROCHEMICALTEMPLATE-FREE METHOO [PTu15]Nanostructures fabricated from conducting polymers have attracted an increase in theinterest in research due their physical, chemical and electronic properties, togetherwith the wide range of potential applications in nanoscience. Templating techniques,such as those employing organic ternplates, ionic surfactants, silicates, polyelectro-lvtes. are commonly employed in the synthesis of nanostructured polvrners. but suchtechniques can have the disadvantage of having to remove the template to obtainthe nanostructured polymer. The electrochemical synthesis of conducting polymeris a technique that avoid the use of a template. In the literature it have been reportedthat polypyrrole microtubule [1J and polyaniline nanowires [2J could be synthesizedby electrochemical polymerization. Compared to the template-synthesis method, thetemplate-free method is simple and cheap because no micro or nano porous mem-branes are used as templates. The electrochemical synthesis provides easy control ofthe film thickness and allows an in situ characterization of the growing film and thefilms properties depends on of the electrochemical conditions used. In this work, thesynthesis of nanowires of poly(3-methylthiohene) by an electrochemical template-freemethod is reported. The influence of the polymerization condition, such concentrationof LiClO., on the nanowires morphology was investigated. The monomer 3-methyl-thiophene was obtained from Aldrich. The electrolyte used was lithium perclorate (AI-drich) in acetonitrile in two different concentrations: 0.1 and 0.3 moIL-1.Electrochemi-cal experiments were carried out with a cell glass with an Ag wire used as quasi-refer-ence electrode. Platinum foils were used as working electrode and counter electrode.The electropolymerization of poly(3-methylthiophene) was carried in solution contain-ing 0.1 moll,:' monomer. The polymerization potential was 1.5 V. The morphology ofpoly(3-methylthiophene) depended strongly on the concentration of dopant used. AsFigure 1 shows. an increase in the concentration of LiClO. favours the formation offibrillar morphology. The SEM clearly shows that using LiCIO. at the concentration of0.1 M no poly(3-methylthiophene) nanowires were observed and a cauliflower rnor-phology was obtained. However, using LiClO. at the concentration of 0.3 M the poly(3-methylthiophene) nanowires were formed. The highest concentration of the support-ing electrolyte implies in higher conductivity [3J.The increase of the conductivity mustprovoke an increase in the accurence of nanowires and this is in agreement with thebehavior observed in the literature for polyaniline nanowires [2J.Acknowledgements:CNPq,CAPES,FAPESPFERROELECTRICITY IN SYNTHETIC METALS: REALlTY ANOHYPOTHESES, [GMA3]The ferroelectricity is one of demanded effects in fundamental and applied solid statephysics. The most recent rise of R&D includes active gate materiais and electric RAMin microelectronics, super-capacitors in portable communicators, sensors in medicalimaging, etc. Till now, the ferroelectrics were available in the inorganic world, some-times in more complex strongly insulating materiais. The recent breakthrough [1]. seereviews [2]. was an unexpected discovery of the ferroelectricity, related to the chargeordering, in typical quasi-l D organic conductors (TMTIF)2X, as well as and in somelayered compounds like d-(EDT-TIFCONMe2)2Br [3J. The dielectric susceptibility,reaching the values - 106, coexists with an unusually high conductivity, which givesrise to the material classified as the "ferroelectric narrow gap semiconductor". TheAlessandra Alves Correa (Embrapa/Bréliil'Ernesto Chaves Pereira (UFSCar/Brazil), 11/1Henrique Capparelli Mattoso (Embrapa/lll.1[1JY.Yanq,M.Wan.J. Mater.Chell1.11(2001)2022-2027.[2JV.Gupta,N.MIIIJ~Electrochem.Commun.. 7 (2005)9% QI)',[3JM. Kabasakaloglu.T Kiyaki.H.T0l1111M.L.Aksu.Appl.SurtoScience.152(I'1'1'1115-125.Serguei Brazovskii (LPTMS-CNRS. Unn/llParis-Sud. Orsay. France). Natasha KJiI"(LPS-CNRS. Université Paris-Sud. OIS:lfFrance)

Influence of the supporting electrolyte concentration on the formation of nanowires of poly(3-methylthiophene) synthesized by an electrochemical template-free method [PTu15].

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http://www.alice.cnptia.embrapa.br/alice/bitstream/doc/27341/1/Proci08.00114.pdf

Influence of the supporting electrolyte concentration on the formation of nanowires of poly(3-methylthiophene) synthesized by an electrochemical template-free method [PTu15].

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