The molecular dynamics of a set of polysulfone polymers have been studied with broadband dielectric spectroscopy. The materials comprise main-chain polysulfones attached to semifluorinated (SF) oxydecylperfluorodecyl side chains. Through the analysis of the dielectric data together with information from differential scanning calorimetry and small-angle X-ray scattering, it can be shown that the oxydecylperfluorodecyl side chains are microphase-separated and form nanodomains with an independent dynamic glass-transition (d SF ) relaxation. In addition to the a process (which is the glass transition of the main chain), other relaxation processes can be detected with Arrhenius-type activation energies of 38-90 6 2 kJ/mol. A g SF process, observed only in polysulfone with SF side chains, can be assigned to librational fluctuations of the perpendicular component of the fluoroalkyl group. A g B relaxation reflects fluctuations of the dipole moments (O¼ ¼S¼ ¼O and C¼ ¼O) of the polymer, whereas a b process, with high activation energies (>70 6 2 kJ/mol), is assigned to packaging defects in the material. A detailed description of the processes is provided together with a proposed relaxation scheme.

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The alignment and relaxation dynamics of a polar dye molecule, N,N-dimethyl-4(4-nitrophenylazo)aniline (DNAA), in zeolite L and perhydrotriphenylene (PHTP) channels were investigated by means of a combination of optical, dielectric, and quantum-chemical methods. Both the zeolite L and PHTP channels enable the dye molecules to align along the channel axis. An amplified net dipole moment of DNAA in PHTP is observed and attributed to enhanced 1D close alignment of dye molecules. In zeolite L channels, a concentration gradient is found with aggregation at the channel entrances. The dynamics of the dye in zeolite L channels reveals localized conical rotational fluctuation modes following Arrhenius-type activation with energy of 0.31 eV, which we assign to small noninteracting fluctuating polar units of the dyes being loosely aligned or isolated. Unlike zeolite L, relaxations in PHTP are characterized by cooperative wobbling motions interpreted as increased intermolecular dipole interaction due to a closely packed one-dimensional array. Temperature-dependent activation energies of 0.25 eV below 0 degrees C and 0.37 eV at ambient temperature reflect the role of the soft channel walls in the activation process.