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We have demonstrated that unsubstituted thiophene can be polymerized by Fe3+‐catalyzed oxidative polymerization inside nanosized thiophene monomer droplets, that is, nanoreactors, dispersed in aqueous medium, which can be performed under acidic solution conditions with anionic surfactant. Besides, we proposed a synthetic mechanism for the formation of the unsubstituted polythiophene nanoparticles in aqueous medium. This facile method includes a FeCl3/H2O2 (catalyst/oxidant) combination system, which guarantees a high conversion (ca. 99%) of thiophene monomers with only a trace of FeCl3. The average particle size was about 30 nm, within a narrow particle‐size distribution (PDI = 1.15), which resulted in a good dispersion state of the unsubstituted polythiophene nanoparticles. Hansen solubility parameters were introduced to interpret the dispersion state of the polythiophene nanoparticles with various organic solvents. The UV–Visible absorption and photoluminescence (PL) spectrum were measured to investigate the light emitting properties of the prepared unsubstituted polythiophene nanoparticle emulsions. According to non‐normalized PL analysis, the reduced total PL intensity of the polythiophene nanoparticle emulsions can be rationalized by self‐absorption in a wavelength range less than 500 nm. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2097–2107, 2008

This process holds great promise for potential applications in 3D chip stacking and all-plastic electronics. Current research is focused on utilizing electropolymerizable precursors other than pyrrole. In particular, tailored monomers could be used to generate micrometer-sized conductive deposits endowed with specific functions, such as recognition properties, for the generation of flexible sensor devices. ExperimentalCommercial polycarbonate filtration membranes (Millipore) with a pore diameter of 1 lm (pore density 8±10 %) were used as substrates. Polypyrrole was obtained by directional electrochemical polymerization (DEP) in aqueous solution from pyrrole monomer (98 %, Aldrich), purified by distillation prior to use, with an EG&G Princeton Research Model 173 potentiostat/galvanostat. An isolating gel produced by immobilizing an appropriate solution in a poly(methyl methacrylate) (PMMA) matrix was deposited by spin-coating on the anode prior to mounting the membrane on the covered electrode. The composition of the gel used was 26 wt.-% PMMA (weight-average molecular weight M w = 120 000), 37 wt.-% propylene carbonate (M w = 102.09), and 37 wt.-% ethylene carbonate (M w = 88.06). The gel components were dissolved in anhydrous tetrahydrofuran (20 mL) by stirring for several hours at room temperature under argon.The structured anodes were fabricated on highly p-doped silicon by first using a mask to etch cavities in the thermally grown isolating oxide layer. Then a lift-off technique was employed to define the chromium±gold electrodes in the etched oxide windows. The metal deposit was a 30 nm thick chromium layer as the adhesion layer, followed by a 300 nm gold layer. Since the silicon oxide was 1 lm thick, the gold electrodes were sunk into the insulating oxide layer by 670 nm.The DEP process was performed at room temperature in a onecompartment cell on a surface of 0.6 cm 2 using a homogeneous platinum counter electrode and a Ag/AgCl reference electrode. The electrolyte solution contained 0.1 M pyrrole and 0.1 M LiClO 4 in water obtained from a Milli-Q Millipore water purification system. The geometry of the electrochemical cell using the patterned electrode has been described previously [20]. A short, high-voltage pulse (2.5 V) was applied during the first 10 s of polymer formation, leading to more homogenous growth of the polymer over the whole surface, followed by potentiostatic growth of the polymer at 1.4 V.Scanning electron microscopy images were obtained with a JEOL Field-Emission Gun Scanning Electron Microscope (JSM 6320F). Conductivity and cross-talk measurements were carried out with a specially built test rig, in which patterned membranes were mounted between the electric contacts of an upper and bottom chip, in combination with a Hewlett±Packard 4140B picoamperemeter±direct-current voltage source. More details are given elsewhere [20±22].

1,4‐Bis[2‐(3,4‐ethylenedioxy)thienyl]‐2,5‐bis[6‐(1′‐butyl‐4,4′‐bipyridyl)hexyloxy]benzene tetrahexafluorophosphate (BEDOTPh‐2V) was synthesized and electropolymerized to form a viologen‐bearing conductive polymer [P(BEDOTPh‐2V)] film on an electrode surface. This polymer exhibits multicolor electrochromic behavior: it is highly transparent light‐blue P(BEDOTPh1.7+‐2V2+) at 1.0 V (vs. Ag/Ag+), pale‐bisque P(BEDOTPh0.6+‐2V2+) at 0.1 V, magenta P(BEDOTPh0‐2V2+) at –0.5 V, purple P(BEDOTPh0‐2V •+) at –0.9 V, and crimson P(BEDOT0‐2V0) at –1.4 V. Since both the viologen pendant and the polymer backbone have cathodic coloring characteristics and their redox‐potential ranges do not overlap each other, the dual electrochromic action provides more plentiful electrochromic colors compared to simple poly{1,4‐bis[2‐(3,4‐ethylenedioxy)thienyl]‐2,5‐dialkoxybenzene}.

[structure: see text] A new liquid crystalline material having an ethylenedioxythiophene-pyridazine-ethylenedioxythiophene (EDOT-PDZ-EDOT) core with two peripheral long alkyl chains was prepared. The designated donor-acceptor-donor (D-A-D)-type core structure induced a distinct smectic liquid crystalline phase due to the strong intermolecular interaction. The photophysical property and the layer structure of the liquid crystal were investigated by differential scanning calorimetry, polarized light microscopy, X-ray diffraction, and cyclic voltammetry.