TY - CONF A1 - Böhning, Martin T1 - Gas transport and molecular mobility in polymer/POSS nanocomposites T2 - Euromembrane 2006 CY - Taormina, Italy DA - 2006-09-24 PY - 2006 AN - OPUS4-11214 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Investigation of swollen polymer/gas-systems: atomistic packing models based on experimental properties T2 - Frühjahrstagung der Deutschen Physikalischen Ges. / AKF Condensed Matter CY - Dresden, Germany DA - 2006-03-26 PY - 2006 AN - OPUS4-11316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Gas Transport and Molecular Mobility in Polymer Based Nanocomposite Systems T2 - 1st International Conference on Advanced Materials and their application, National Research Centre, Physics Division CY - Cairo, Egypt DA - 2005-12-12 PY - 2005 AN - OPUS4-10976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Small Molecules in Polymers and Polymer based Nanocomposites - Molecular Probes for Material Characterization and Design T2 - Polydays 2004 (Berliner Polymerentage); Universität Potsdam, Campus "Am Neuen Palais" CY - Potsdam, Germany DA - 2004-10-04 PY - 2004 AN - OPUS4-7297 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin A1 - Goering, Harald T1 - Preparation and Characterisation of Nanoscaled Nanostructured Materials T2 - Nanofair 2004 CY - Karlsruhe, Germany DA - 2004-11-22 PY - 2004 AN - OPUS4-7296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin A1 - Robertson, Daniela A1 - Schröder, Hartmut T1 - Autoclave testing: a new approach for the evaluation of oxidative long-term resistance of geosynthetics N2 - Oxidative long time resistance is essential for many polyolefin based products, especially if repair or exchange is not possible as encountered in many building and geotechnical applications. Current regulations and recommendations for geosynthetics cover mainly the needs of a maximum lifetime of 25 years, though many applications require longer lifetimes up to 100 years and more. Reliable testing of the long time oxidation resistance is complicated by the complex interplay of physicochemical processes and reactions in combination with the need of relatively short testing durations, usually not exceeding 12 months. Thus for conventional atmospheric oven testing, the use of temperatures higher than 100 °C is inevitable, making conclusive Arrhenius extrapolations often questionable. Practical assessments of oxidative durability consist of exposures under accelerated ageing conditions with subsequent characterization of exposed material samples with respect to their residual stabilization and/or their mechanical properties. The autoclave test combines exposures at elevated temperatures with higher oxygen pressures and is performed with material samples immersed in a well defined aqueous medium representing critical environments in geosynthetic applications and including extraction of additives. Under these conditions meaningful results can be obtained within reasonable testing durations at only moderately elevated temperatures up to 80 °C. Application of different physicochemical methods, such as tensile testing, OIT /HP-OIT and analysis of residual antioxidant content (ICOT), in order to determine the time dependent degradation behaviour, reveal valuable information about mechanisms and effectiveness of the used antioxidants. Corresponding results for exposures at different temperatures and oxygen pressures are the basis for a 3D-extrapolation in order to estimate the expected service life. Different empirical models are presented and discussed with respect to their practical impact. T2 - EuroGeo4, 4th European Geosynthetics Conference CY - Edinburgh, UK DA - 2008-09-07 KW - Ageing KW - Degradation KW - Geotextiles KW - Polyolefin KW - Polypropylene KW - Oxidative resistance KW - Lifetime prediction PY - 2008 IS - Paper 143 SP - 1 EP - 8 AN - OPUS4-18424 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heuchel, M. A1 - Hölck, Ole A1 - Böhning, Martin A1 - Siegert, R. A1 - Hofmann, D. ED - Qi, Y. ED - H.E. Fang, ED - N. Reynolds, ED - Liu, Z.-K. T1 - Knowledge-based approach to gas sorption in glassy polymers by combining experimental and molecular simulation techniques N2 - We present a method which allows to calculate gas sorption in complex polymers where, as slow processes, gas induced plasticization and volume dilation are important factors. Since the relaxational swelling of the polymer matrix that is observed at elevated gas concentrations takes hours or days, the swelling process is orders of magnitudes too slow to simulate the respective molecular dynamics in reasonable time and effort. To address this apparent incompatibility of experiment and simulation, we use single representative reference states from experiment and construct atomistic packing models according to these specifications. Gas sorption of CO2 and CH4 was successfully calculated on polysulfone, a 6FDA-polyimide, and a polymer of intrinsic microporosity, PIM-1, at 308 K and pressures up to 50 bar. T2 - MRS Fall Meeting 2008 - Symposium W - Computational Materials Design via Multiscale Modeling CY - Boston, MA, USA DA - 2008-12-01 KW - Gas sorption KW - Molecular modelling KW - Simulation KW - Glassy polymers PY - 2009 DO - https://doi.org/10.1557/PROC-1130-W06-10 VL - 1130 SP - W06 EP - W10 AN - OPUS4-19106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Gas sorption in glassy polymers - Comparative characterization using experimental and molecular modeling techniques T2 - EUROMEMBRANE 2009 Conference CY - Montpellier, France DA - 2009-09-06 PY - 2009 AN - OPUS4-20018 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Böhning, Martin A1 - Hölck, Ole A1 - Heuchel, M. A1 - Hofmann, D. T1 - Characterization of gas sorption in glassy polymers combining experimental and molecular modeling techniques KW - Glassy Polymers KW - Gas Sorption KW - Molecular Modelling KW - Diffusion PY - 2008 SN - 0743-0515 VL - 98 SP - 875 EP - 876 PB - Division of Polymeric Materials Science and Engineering, American Chemical Society CY - Washington, DC AN - OPUS4-17485 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Autoclave testing - a new approach for the evaluation of oxidative long-term resistance of geosynthetics T2 - 4th European Geosynthetics Conference CY - Edinburgh, Scotland DA - 2008-09-07 PY - 2008 AN - OPUS4-18295 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Gas transport in glassy polymers and PNCs - experiment, analysis, modeling of diffusion, sorption and dilation T2 - Workshop: Polymers, University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture, Laboratory for Non-Metals CY - Zagreb, Croatia DA - 2012-05-23 PY - 2012 AN - OPUS4-25969 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Gas transport in glassy polymers and PNCs - experiment, analysis, modeling of diffusion, sorption and dilation T2 - Workshop: Nanostructured and Nanocomposite Membranes for Gas und Vapour Separation CY - Cetraro, Italy DA - 2012-05-15 PY - 2012 AN - OPUS4-26631 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Correlation of gas diffusivity and local chain mobility in polycarbonate/POSS nanocomposites as determined by broadband dielectric relaxation spectroscopy T2 - Euromembrane 2012 CY - London, England DA - 2012-09-23 PY - 2012 AN - OPUS4-26629 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -