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Sol−gel polymerization of organotrialkoxysilanes RSi(OR‘)3 and formation of silsesquioxane (SSQO) structures was followed using SEC, 29Si NMR, and both small- and wide-angle X-ray scattering. Evolution of the SSQO structure is controlled by the competition between intermolecular polycondensation and cyclization. A strong tendency to buildup of polyhedral cyclic oligomersmainly octamer “cages” and larger cagelike structureswas found to grow with increasing size of substituent R. As a result, long substituents prevent gelation of the trifunctional system and increase stability of the SSQO. Because of incompatibility of the polyhedral SSQO framework and pendant organic chains, microphase separation takes place and spontaneous self-organization occurs. A micellar arrangement of compact SSQO domains with a correlation distance corresponding to the size of the substituent is formed, and the ordering is promoted by increasing length of the organic chain. The most organized arrangement was observed with the trialkoxysilanes substituted with long PEO chains which crystallize and force the SSQO cages to align in the lamellar structure.

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Polyaniline (PANI) was prepared by the oxidation of aniline in the presence of various inorganic and organic acids at 20 • C and −50 • C. When strong acids were used, the conductivity of the protonated PANI was typically 1-10 S cm −1 . The results indicate that the protonation of PANI in media containing carboxylic acids was achieved with the help of sulfuric acid produced during the reaction with ammonium peroxydisulfate. The conductivity of PANI prepared under such conditions was reduced. Partial benzene-ring sulfonation has been proposed to explain the wide range in conductivity of PANI bases, 10 −11 -10 −7 S cm −1 . The densities of the samples reflect the nature of the acid used. The densities of the corresponding PANI bases exhibit much less variation. Molecular weight and degree of crystallinity of PANI are higher when the polymerization is carried out at −50 • C. The conductivity of the PANI is determined mainly by way of protonation. The effects of molecular weight and of crystallinity on PANI conductivity are marginal.

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