TY - CONF A1 - Just, Ulrich A1 - Weidner, Steffen A1 - Wittke, Wolfgang A1 - Friedrich, Jörg Florian A1 - Rittig, F. A1 - Gruber, F. T1 - 2D-Characterization of Polyamides using Chromatography and MALDI-TOF-MS T2 - Waters International GPC 2003 and ISPAC-16-Symposium CY - Baltimore, MD, USA DA - 2003-06-09 PY - 2003 AN - OPUS4-2631 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidner, Steffen A1 - Just, Ulrich A1 - Wittke, Wolfgang A1 - Rittig, F. A1 - Gruber, F. A1 - Friedrich, Jörg Florian T1 - Analysis of modified polyamide 6.6 using coupled liquid chromatography and MALDI-TOF-mass spectrometry KW - MALDI-TOF-MS KW - Liquid chromatography KW - Coupling methods PY - 2004 SN - 0168-1176 SN - 0020-7381 SN - 1387-3806 SN - 1873-2798 VL - 238 IS - 3 SP - 235 EP - 244 PB - Elsevier CY - Amsterdam AN - OPUS4-6966 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rittig, F. A1 - Gruber, F. A1 - Just, Ulrich A1 - Schrepp, W. A1 - Wittke, Wolfgang A1 - Weidner, Steffen T1 - Characterization of Polyamides using new combined techniques T2 - Vortragstagung der Fachgruppe Makromolekulare Chemie der GDCh CY - Düsseldorf, Germany DA - 2004-03-15 PY - 2004 AN - OPUS4-11142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rittig, F. A1 - Gruber, F. A1 - Schrepp, W. A1 - Just, Ulrich A1 - Wittke, Wolfgang A1 - Weidner, Steffen T1 - Characterization of polyamides using new combined techniques T2 - GDCh - Vortragstagung, Fachgruppe Makromolekulare Chemie CY - Düsseldorf, Germany DA - 2004-03-15 PY - 2004 AN - OPUS4-11137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rittig, F. A1 - Gruber, F. A1 - Schrepp, W. A1 - Just, Ulrich A1 - Weidner, Steffen A1 - Wittke, Wolfgang T1 - Characterization of Polyamides using new combined techniques T2 - Unesco-IUPAC-Polymer Convention CY - Stellenbosch, South Africa DA - 2004-04-05 PY - 2004 AN - OPUS4-11141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rittig, F. A1 - Gruber, F. A1 - Just, Ulrich A1 - Wittke, Wolfgang A1 - Friedrich, Jörg F. A1 - Weidner, Steffen T1 - Characterization of technical polymers using liquid chromatography as well as hyphenated techniques T2 - Waters International GPC 2003 and ISPAC-16 Symposium CY - Baltimore, MD, USA DA - 2003-06-09 PY - 2003 AN - OPUS4-4654 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rittig, F. A1 - Fandrich, N. A1 - Schrepp, W. A1 - Urtel, M. A1 - Weberndörfer, B. A1 - Just, Ulrich A1 - Weidner, Steffen A1 - Wittke, Wolfgang T1 - Characterization of Polyacetals by comprehensive 2D Liquid Chromatography and hyphenated techniques T2 - 2. International Symposium on the Separation and Chracterization of Natural and Synthetic Macromolecules SCM-2 CY - Amsterdam, Netherlands DA - 2005-02-02 PY - 2005 AN - OPUS4-11154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönhals, Andreas A1 - Rittig, F. A1 - Kärger, J. T1 - Self-diffusion of poly(propylene glycol) in nanoporous glasses studied by pulsed field gradient NMR: A study of molecular dynamics and surface interactions N2 - Pulsed field gradient NMR is applied to investigate the self-diffusion of poly(proypylene glycol) in nanoporous glasses (nominal pore sizes of 2.5–7.5 nm). In general, the diffusion is slowed down by the confinement compared to the bulk. For native pore surfaces covered by hydroxyl groups the spin echo attenuation Ψ displays a bimodal behavior versus q2t (q-norm of a generalized scattering vector). This was explained assuming spatial regions of different diffusivities in a two-phase model. The slow component is assigned to segments forming a surface layer close to the pore walls in which the segments have a lower mobility than those located in the center of the pores. By variation of observation time it was concluded that time constant for the dynamic exchange of segments between these two regions is around 100 ms at room temperature. For silanized pores, the bimodal behavior in the spin echo attenuation Ψ shows a stretched exponential decay versus q2t. The estimated diffusion coefficients decrease strongly with decreasing pore size. The temperature dependence of the diffusion coefficient can be approximated by an Arrhenius law where the activation energy increases with decreasing pore size. The observed pore size dependence for the diffusion of poly(propylene glycol) in silanized nanoporous glasses can be discussed assuming interaction and confining size effects. KW - Glass KW - Molecular dynamics method KW - Nanoporous materials KW - Polymers KW - Self-diffusion KW - Spin echo (NMR) PY - 2010 DO - https://doi.org/10.1063/1.3479905 SN - 0021-9606 SN - 1089-7690 VL - 133 IS - 9 SP - 094903-1 - 094903-7 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-22000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -