Nanostructured Poly Pyrrole

PPy-MMT nanocomposites have also been prepared using ammonium persulfate as oxidant [ 111,112]. Similar to the other cases, the FTIR spectrum of PPy-MMT show bands that can be related to both PPy and Clay. Peaks at ca. 1041, 523, and 468 cm corresponding to J/si-o-si. t si-o, and 8si.o, respectively, are characteristic of MMT [113]. The bands at ca. 1554, 1468, 1294, and 1189 cm have been attributed to the PPy chain [ 114,115], displaying small shifts in comparison to the bands of pristine PPy. For example, the band at 1454 cm in the spectrum of pure PPy occurs at 1442 cm for PPy-MMT (1 wt% of MMT) and at 1440 cm for PPy-MMT (10 wt% of MMT) nanocomposites. A higher band situated at 3434 cm (N—H stretching vibration) in the PPy spectrum is shifted to 3440 and 3446 cm for PPy-MMT (1 wt% of MMT) and for PPy-MMT (10 wt% of MMT) nanocomposites, respectively. Thus, the FTIR spectroscopy supplies 

The XPS spectrum of PPy-MMT is dominated by the main MMT features O Is (531 eV), Si 2p (103 eV), and A1 2p (74 eV), a qualitative indication that the nanocomposite surface is MMT-rich. The contributions of the major elements characteristic of PPy, i.e. C and N, increase with PPy loading, and simultaneously those of Si, Al, and O (the major ones in the clay) decrease. PPy is thus gradually loaded at the surface of the nanocomposites as the initial pyrrole concentration increases. However, the surface N/Si ratios 0.04, 0.05, 0.06, and 0.11 determined for PPy mass loadings of 2.8, 10.8, 13.3, and 21.4%, respectively, are lower than those determined for the bulk of the nanocomposites by elemental analysis. 

Coral-hke nanowires and nanowire networks of conducting PPy have been synthesized by chemical oxidation polymerization of pyrrole monomers in a dodecyl-benzene sulfonic acid (DBSA) aqueous solution with FeCla as oxidant and poly(vinyl-alcohol) (PVA) as 

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In the second approach to self-assembly of polymer-silica nanocomposites, polymerizable surfactants are employed both to direct self-assembly into ordered mesophases and to serve as organic monomers which can be subsequently polymerized. For instance, Brinker et al. developed nonionic surfactants incorporating diacy-telene groups which could be polymerized upon irradiation by UV light.68 69 Similarly, poly(thiophene)70 and poly(pyrrole)71 have been successfully integrated into silica nanostructures in this manner. Importantly, this in situ polymerization produces isolated molecular wires, rather than clustered bundles of conductive polymer.70... 

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