Glassy dynamics and charge transport are studied for the polymeric Ionic Liquid (PIL) poly[tris(2-(2-methoxyethoxy)ethyl)ammonium acryloxypropyl-sulfonate] (PAAPS) with varying molecular weight (9700, 44200, 51600 and 99500 g/mol) by Broadband Dielectric Spectroscopy (BDS) in a wide frequency (10 −2 -10 7 Hz) and temperature range (100 -400 K) and by DSC-and AC-chip calorimetry. The dielectric spectra are characterized by a superposition of (i) relaxation processes, (ii) charge transport and (iii) electrode polarization. The relaxation processes (i) are assigned to the dynamic glass transition and a secondary relaxation. Charge transport (ii) can be described by the random free-energy barrier model as worked out by Dyre et al.; the Barton-Namikawa-Nakajima (BNN) relationship is well fulfilled over more than 8 decades. Electrode polarization (iii) follows the characteristics as analyzed by Serghei et al.; 2 with deviations on the low frequency side. The proportionality between the relaxation rate of the dynamic glass transition and the charge carrier hopping rate reflects the nature of charge transport as glass transition assisted hopping. Hereby, the PIL under study exposes the highest dc-conductivity values observed for this class of materials below 100 • C, so far; and for the first time a conductivity increase by rising degree of polymerization. The comparison of the polymeric Ionic Liquids under study with others implies conclusions on the design of novel highly conductive PILs. ExperimentalFourier-transform infrared (FTIR) spectroscopy measurements are accomplished in transmission mode on a Bio-Rad FTS 6000 spectrometer equipped with a UMA-500 microscope. The liquid samples (9700 g/mol and 99500 g/mol) are squeezed between two BaF 2 IR windows, while the intensity is recorded by means of a mercury-cadmium-telluride (MCT) detector (Kolmar Technologies) with a frequency resolution of 2 cm −1 .

Polymeric ionic liquids (PILs) form a novel class of materials in which the extraordinary properties of ionic liquids (ILs) are combined with the mechanical stability of polymeric systems qualifying them for multifold applications. In the present study broadband dielectric spectroscopy (BDS), Fourier transform infrared spectroscopy (FTIR), AC-chip calorimetry (ACC) and differential scanning calorimetry (DSC) are combined in order to unravel the interplay between charge transport and glassy dynamics. Three low molecular weight ILs and their polymeric correspondents are studied with systematic variations of anions and cations. For all examined samples charge transport takes place by glassy dynamics assisted hopping conduction. In contrast to low molecular weight ILs the thermal activation of DC conductivity for the polymeric systems changes from a Vogel-Fulcher-Tammann-to an Arrhenius-dependence at a (sample specific) temperature T s 0 . This temperature has been widely discussed to coincide with the glass transition temperature T g , a refined analysis, instead, reveals T s 0 of all PILs under study at up to 80 K higher values. In effect, below the T s 0 charge transport in PILs becomes more efficient -albeit on a much lower level compared to the low molecular weight pendants -indicating conduction paths along the polymer chain. This is corroborated by analysing the temperature dependence of specific IR-active vibrations showing at T s 0 distinct changes in the spectral position and the oscillator strength, whereas other molecular units are not affected. This leads to the identification of charge transport responsive (CTR) as well as charge transport irresponsive (CTI) moieties and paves the way to a refined molecular understanding of electrical conduction in PILs.platinum sensor to determine the water content of the P(ILs) after synthesis. HYDRANAL Coulomat AG water standards from Riedel-de Haën were used for calibration.

Poly(ionic liquid)s with different topologies are investigated towards the gating effects for the first time.

A homologous series of 16 polymeric ionic liquids (PIL) are investigated based on monovalent and bivalent telechelic polyisobutylene (PIB) carrying the ionic liquid (IL)-like cationic headgroup (N,N,N-triethyl­ammonium or 1-methyl­pyrrolidinium) and Br, NTf2, OTf, or pTOS as anions. Molecular dynamics, charge transport, and polarization at mesoscopic scales are analyzed over a wide frequency (10–2–107 Hz) and temperature (200–400 K) range by means of broadband dielectric spectroscopy (BDS); additionally, differential scanning calorimetry (DSC) is employed. In detail, (i) three molecular relaxation processes are observed including the dynamic glass transition of the polymeric matrix, (ii) a conductivity relaxation originating from charge transport in the IL-like moieties, and (iii) a weak electrode polarization caused by the accumulation of mobile charge carriers at the metal interfaces. The net conductivity of the PIL as a whole is quantitatively described by an effective-medium approximation (EMA) reflecting the microphase-separated character of the PIL under study.

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