This paper reports a novel supercapacitor electrode design based on poly(3,4-propylenedioxypyrrole) (PProDOP) electropolymerized onto thin films of single walled carbon nanotubes (SWNTs) on glass substrates. This permits the electropolymerization of thicker PProDOP films than can be deposited onto flat gold-coated Kapton electrodes and a correspondingly greater capacitance per unit area. A pyrene functionalized polyfluorene, designated Sticky-PF, was designed and used as an effective monolayer interfacial adhesion modifier between the SWNT films and PProDOP via noncovalent self-assembly onto the SWNT film surfaces before polymer electrodeposition. The thickness of the electrodeposited PProDOP was found to be self-limiting at thicknesses characteristic of each substrate electrode. Optimized areal capacitance values for PProDOP on flat gold and Sticky-PF coated SWNT films were measured to be 8.1 mF/cm 2 and 16.4 mF/cm 2 , respectively, with the twofold enhancement due to the thicker films possible on the SWNT electrode. The specific capacitance of PProDOP on gold and Sticky-PF|SWNT film substrates were found to be similar at 141 F/g and 122 F/g, respectively, indicating the capacitance to be due to the electroactive polymer. The areal capacitance values of the corresponding supercapacitor devices constructed with Au/Kapton substrates was 3.2 mF/cm 2 , whereas a significantly greater value of 8.8 mF/cm 2 was measured for the Sticky-PF|SWNT film substrates. The supercapacitors prepared using the Au/Kapton substrates were highly stable, retaining 80% of their electroactivity after 32 700 nonstop charge/discharge cycles (100% depth of discharge). Supercapacitors made using the Sticky-PF|SWNT substrates showed a steady loss of capacitance to about 57% of the original value (to 5.0 mF/cm 2 ) after 32 700 charge/discharge cycles, which was still 38% larger than the initial capacitance of the gold electrode devices.

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We have developed a novel composite film fabrication process that utilizes the soft lithographic approach, Particle Replication in Nonwetting Templates (PRINT). This process was found to be a very viable approach to the fabrication of well-structured, multifunctional polymer composite thin films. Particle aggregation was completely eliminated as discretely molded particles with specific shape, size and composition were maintained in well-defined arrays determined by the silicon master template. Both all-organic and polymer-ceramic composites have been generated using this technique with particle inclusions ranging in size from 200 nm to 20 μm. The composition of the composite was well-controlled with both cross-linked and thermoplastic polymeric continuous phases, as well as particle compositions ranging from cross-linked polymeric resins to the inorganic oxide, barium titanate.

In this work, characterization of a homopolymer of succinic acid bis(4‐pyrrol‐1‐ylphenyl) ester prepared by galvonastatic polymerization was carried out by direct pyrolysis mass spectrometry. Although decomposition of the monomer yielding mainly butadionic acid and pyrrole occurred under the galvonastatic polymerization conditions, growth of the polymer through the pyrrole moieties was also achieved, yielding a ladder‐type polymer film. The polypyrrole chains contained both quinoid and aromatic units as in the case of polypyrrole, yet the extent of network structure was significantly diminished. A three‐step mechanism is proposed for the thermal decomposition process. The first step involves the cleavage of C4H4NC6H4O end groups. In the second step, decomposition of phenyl ester units and polypyrrole chains having quinoid structure takes place. The final stage of thermal degradation was attributed to decomposition of polypyrrole chains having aromatic structure. Copyright © 2004 Society of Chemical Industry

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