TY - JOUR A1 - Schönhals, Andreas A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner A1 - Schick, Ch. T1 - The molecular dynamics of polymers in random nanometre confined spaces investigated by relaxational and scattering techniques JF - Journal of physics / Condensed matter PY - 2003 SN - 0953-8984 SN - 1361-648X VL - 15 SP - S1139 EP - S1148 PB - IOP Publ. Ltd. CY - Bristol AN - OPUS4-2463 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mach, Reinhard A1 - Klotz, Hans-Dieter A1 - Oleszak, Franz A1 - Maneck, Heinz-Eberhard A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner T1 - Synthesis and characterization of nanoscaled and nanostructured carbon containing materials produced by thermal plasma technology JF - Applied surface science N2 - Single-walled carbon nanotubes (SWNT) and carbon nitride films are synthesized by a direct current (dc) arc discharge at slightly reduced pressure and by an inductively coupled r.f. plasma (ICP) at atmospheric pressure, respectively. By treatment with nitric acid SWNT are purified from by-products and characterized by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. ICP allows the deposition of carbon nitride films on steel substrate. The deposition of the films creates a relatively strong radial symmetric profile. The structure of the films are rather independent of the distance between substrate and plasma. Raman, Fourier transform infrared (FTIR), and energy dispersive X-ray (EDX) spectroscopy are used for analyzing the carbon nitride materials. T2 - 11th Conference on Applied Surface Analysis (AOFA) CY - Leipzig, Germany DA - 2000-09-24 KW - Single-walled carbon nanotubes KW - Carbon nitride films KW - Arc discharge KW - Inductively coupled r.f.plasma PY - 2001 DO - https://doi.org/10.1016/S0169-4332(01)00253-7 SN - 0169-4332 SN - 1873-5584 VL - 179 IS - 1-4 SP - 1 EP - 7 PB - North-Holland CY - Amsterdam AN - OPUS4-1023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönhals, Andreas A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner A1 - Schick, C. T1 - Behaviour of polymers confined to nanoporous glasses studied by dielectric, thermal and vibrational spectroscopy - Cut - off length scale for glass transition? JF - Verhandlungen der Deutschen Physikalischen Gesellschaft T2 - Frühjahrstagung des Arbeitskreises Festkörperphysik bei der DPG CY - Regensburg, Germany DA - 2002-03-11 PY - 2002 SN - 0420-0195 SN - 0372-5448 SN - 0343-9216 IS - CPP 7.2 SP - 428 CY - Bad Honnef AN - OPUS4-2029 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönhals, Andreas A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner A1 - Schick, C. T1 - Molecular dynamics of polymers in random nanometer confinements investigated by relaxational scattering techniques JF - Journal of physics / Condensed matter N2 - Dielectric spectroscopy and temperature-modulated differential scanning calorimetry are employed to study the molecular dynamics of oligomeric poly(propylene glycol) (PPG) melts of different molecular weights confined to nanoporous glasses (pore sizes 2.5, 5.0, 7.5 and 20 nm). Moreover, the results obtained for the polymers are compared with those for the corresponding monomer. The experimental results are discussed in the framework of the interplay of confinement and adsorption effects. For large pore sizes (> 5 nm) a speeding up of the molecular dynamics is observed (the confinement effect), whereas for small pore sizes (< 5 nm) a slowing down of the segmental fluctuations is found (the adsorption effect). In addition, a minimal length scale for the glass transition of 1.6 nm is estimated for PPG confined in nanoporous glasses. This supports the idea that the molecular motions responsible for the glassy dynamics must be describable by a characteristic length scale. Polarized Raman scattering investigations are carried out to investigate the conformations of the macromolecules inside the pores. These experiments show that the confined polymer chains are locally stretched. This effect increases with decreasing pore size. T2 - 3rd Workshop on Non-Equilibrium Phenomena in Supercooled Fluids, Glasses and Amorphous Materials CY - Pisa, Italy DA - 2003-09-22 PY - 2003 DO - https://doi.org/10.1088/0953-8984/15/11/334 SN - 0953-8984 SN - 1361-648X VL - 15 IS - 11 SP - S1139 EP - S1148 PB - IOP Publ. Ltd. CY - Bristol AN - OPUS4-2041 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Goering, Harald A1 - Maneck, Heinz-Eberhard A1 - Mach, Reinhard A1 - Knoll, Uta A1 - Oleszak, Franz A1 - Gajewski, Sven A1 - Brzezinka, Klaus-Werner T1 - Synthese von Nano-Materialien - Fullerene, Kohlenstoff-Nanoröhren, Nanopulver und Schichten T2 - Materialica 2002 T2 - Materialica 2002 ; 5. Internationale Fachmesse für Werkstoffanwendungen, Oberflächen und Product Engineering CY - München, Deutschland DA - 2002-09-30 PY - 2002 SP - 1 EP - 2 AN - OPUS4-2059 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Böhning, Martin A1 - Tidjani, Adams A1 - Wald, Oliver A1 - Brzezinka, Klaus-Werner A1 - Turky, Gamal A1 - Goering, Harald A1 - Schartel, Bernhard A1 - Schönhals, Andreas T1 - Dielectric and gas transport properties of polypropylene-clay nanocomposites JF - Verhandlungen der Deutschen Physikalischen Gesellschaft T2 - Frühjahrstagung des Arbeitskreises Festkörperphysik bei der DPG CY - Regensburg, Germany DA - 2002-03-11 PY - 2002 SN - 0420-0195 SN - 0372-5448 SN - 0343-9216 IS - CPP 5.4 SP - 425 CY - Bad Honnef AN - OPUS4-2036 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin A1 - Tidjani, Adams A1 - Wald, Oliver A1 - Turky, Gamal A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner A1 - Schartel, Bernhard A1 - Schönhals, Andreas T1 - Polypropylene/Clay Nanocomposites - Gas Transport Characteristics and Molecular Mobility T2 - Polydays 2002 T2 - Polydays 2002 CY - Berlin, Germany DA - 2002-09-30 PY - 2002 SP - 1(?) EP - 2(?) AN - OPUS4-2038 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin A1 - Wald, Oliver A1 - Turky, Gamal A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner A1 - Schartel, Bernhard A1 - Schönhals, Andreas T1 - Dielectric Relaxation and Gas Transport Properties in Polypropylene Based Nanocomposites T2 - Proceedings of the ACS 2002 Biennial Symposium "Polymeric Nanomaterials" T2 - ACS 2002 Biennial Symposium "Polymeric Nanomaterials" CY - Rohnert Park, CA, USA DA - 2002-11-17 PY - 2002 SP - 1(?) EP - 3(?) AN - OPUS4-2035 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Böhning, Martin A1 - Goering, Harald A1 - Fritz, Andreas A1 - Brzezinka, Klaus-Werner A1 - Turky, Gamal A1 - Schönhals, Andreas A1 - Schartel, Bernhard T1 - Dielectric Study of Molecular Mobility in Poly(propylene-graft-maleic anhydride)/Clay Nanocomposites JF - Macromolecules N2 - Polymer/clay nanocomposite materials based on poly(propylene-graft-maleic anhydride) (PPgMAH) and two different organophilic modified clays were investigated by dielectric relaxation spectroscopy (DRS). In contrast to ungrafted polypropylene (PP), PPgMAH shows a dielectrically active relaxation process which can be assigned to localized fluctuations of the polar maleic anhydride groups. Its relaxation rate exhibits an unusual temperature dependence, which could be attributed to a redistribution of water molecules in the polymeric matrix. This is confirmed by a combination of Raman spectroscopy and thermogravimetric experiments (TGA) with real-time dielectric measurements under controlled atmospheres. In the nanocomposites this relaxation process is shifted to higher frequencies up to 3 orders of magnitude compared to the unfilled polymer. This indicates a significantly enhanced molecular mobility in the interfacial regions. In the nanocomposite materials a separate high-temperature process due to Maxwell-Wagner-Sillars (MWS) polarization was observed. The time constant of this MWS process can be correlated with characteristic length scales in nanocomposites and therefore provides additional information on dispersion and delamination/exfoliation of clay platelets in these materials. These properties also influence the diffusivity of the water molecules as revealed by real-time dielectric investigations. KW - Polymer clay nanocomposites KW - Molecular mobility KW - Dielectric relaxation spectroscopy PY - 2005 DO - https://doi.org/10.1021/ma048315c SN - 0024-9297 SN - 1520-5835 VL - 38 IS - 7 SP - 2764 EP - 2774 PB - American Chemical Society CY - Washington, DC AN - OPUS4-7281 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -