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Fiber-shaped aggregates were obtained from aqueous solutions of 5-octadecyloxyisophthalic acid neutralized with 1.5 equiv of KOH. The structure of the aggregates in the resulting suspensions was investigated by X-ray and electron diffraction (ED) studies; the morphological observations reported here stem from atomic force microscopy (AFM) studies and from polarized optical microscopy (OM). The aggregate formation was examined as a function of the concentration and temperature of the isophthalate solutions or suspensions. The structure elucidation shows that the aggregates consist of crystals as the smallest subunits. Their structure was determined, and the cell parameters of the unit cell could be established. Furthermore, it is demonstrated that the material obtained from the aqueous suspensions, by pulling fiber-shaped species mechanically, is a continuous sequence of crystals.

The emission at 669 nm of metal free phthalocyanine in toluene and 1-bromonaphthalene solutions

The fluorescence decay of pyrene quenched by benzophenone in cetyltrimethyl ammonium chloride solutions has been studied. On addition of chlorate ions to the solution, a transition to long rod-like micelles are known to occur. The fluorescence decay pattern changes in the transition region, from a typical micellar quenching behaviour, following the equation suggested by Infelta, Thomas and Gratzel [22] via the type of decay suggested for polydisperse micelles (Almgren and Lofroth [18]) to a decay pattern which is independent of the chlorate concentration at high concentrations and follows an equation derived for quenching in infinite rods. The weight average aggregation numbers and the widths of the micelle size distributions were determined in the transition region.