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We show that the emeraldine base form of polyaniline (PANI) forms self-organized (mesomorphic) structures upon mixing with an amphiphilic oligomer zinc dodecyl benzenesulfonate, Zn(DBS)2. The number of Zn(DBS)2 molecules vs the number of PhN repeat units of PANI was selected to be x = 0, 0.125, 0.25, 0.5, and 1.0, and the mixtures were denoted as PANI[Zn(DBS)2] x according to their nominal compositions. PANI consists of alternating quinone diimine and benzene diamine groups. FT-IR and UV−vis spectroscopies reveal changes in the quinone diimine moieties upon adding Zn(DBS)2, thus suggesting coordination to the iminic nitrogens to form comb-shaped supramolecules PANI[Zn(DBS)2]0.5. Their structure formation was studied using small-angle X-ray scattering and electron microscopy. The competition between the attraction (coordination) and repulsion (dodecyl tails) leads to a self-organized lamellar phase with a long period of ca. 31 Å. Further increase of Zn(DBS)2 did not reveal clear changes in FT-IR and UV−vis but results in plasticization to render viscous fluid upon heating for x = 1.0, in contrast to the uncomplexed PANI which is infusible.

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A novel cryogenic modulator was constructed for comprehensive two-dimensional gas chromatography (GC x GC). The modulator is based on two-step cryogenic trapping with CO2 and thermal desorption with electric heating. The GC x GC system included a nonpolar first-dimension column and two semipolar second-dimension columns, one connected to a flame ionization detector and the other one to a electron capture detector. A Matlab-based program, which allowed determination of peak heights and volumes, was written for the data analysis. The GC x GC system was applied for the analysis of polyaromatic hydrocarbons and polychlorinated biphenyls. The functioning of the modulator and the quantitativity of the method were studied with both peak volumes and peak heights from a three-dimensional plot. The separate peak areas from the modulated chromatogram were calculated as a comparison. The quantitative results were compared with those obtained with the same system but without the thermal modulation. The method was found to be repeatable and linear with use of peak volumes as well as peak heights. There was also good agreement with the results obtained by integration of separate peak areas. The developed GC x GC method was applied to the analysis of a Soxhlet extract of a certified sediment sample. The results were compared with the certified values.

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