TY - JOUR A1 - Unger, R. A1 - Braun, Ulrike A1 - Fankhänel, J. A1 - Daum, B. A1 - Arash, B. A1 - Rolfes, R. T1 - Molecular modelling of epoxy resin crosslinking experimentally validated by near-infrared spectroscopy N2 - Reliable simulation of polymers on an atomistic length scale requires a realistic representation of the cured material. A molecular modelling method for the curing of epoxy systems is presented, which is developed with respect to efficiency while maintaining a well equilibrated system. The main criterion for bond formation is the distance between reactive groups and no specific reaction probability is prescribed. The molecular modelling is studied for three different mixing ratios with respect to the curing evolution of reactive Groups and the final curing stage. For the first time, the evolution of reactive groups during the curing process predicted by the molecular modelling is validated with near-infrared spectroscopy data, showing a good agreement between simulation results and experimental measurements. With the proposed method, deeper insights into the curing mechanism of epoxy systems can be gained and it allows us to provide reliable input data for molecular Dynamics simulations of material properties. KW - Epoxy KW - NIR spectroscopy KW - Modelling PY - 2019 DO - https://doi.org/10.1016/j.commatsci.2019.01.054 SN - 0927-0256 VL - 161 SP - 223 EP - 235 PB - Elsevier AN - OPUS4-47431 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike T1 - Analytik von Mikroplastik mittels Thermoextraktion Desorption Gas Chromatographie Massen Spektrometrie (TED-GC-MS): Nun auch die Luft? N2 - Der Vortrag gibt eine Überblick über die Messung von Mikroplastik mittels TED-GC-MS mit speziellem Fokus auf Luftgetragene Partikel T2 - Odour and Emissions of Plastic Materials CY - Kassel, Germany DA - 19.03.2019 KW - Mikroplastik KW - Standarisierung KW - Analytik PY - 2019 AN - OPUS4-47583 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lörchner, Dominique A1 - Dittmann, Daniel A1 - Braun, Ulrike A1 - Kroh, L. W. A1 - Köppen, Robert T1 - Investigation of two triazine-based heterocyclic brominated flame retardants by coupled thermogravimetry-Fourier transform infrared spectroscopy N2 - In this study, the thermal decomposition of 1,3,5-tris-(2,3-dibromopropyl)-1,3,5-triazine-2,4,6-trione (TDBPTAZTO) and 2,4,6-tris-(2,4,6-tribromo-phenoxy)-1,3,5-triazine (TTBP-TAZ) were investigated for the first time by thermogravimetric analysis. Both compounds were thermal degraded between 225 and 350 °C (TDBP-TAZTO) as well as 300 and 400 °C (TTBP-TAZ). As a result, mass loss (%) of 98.5% for TTBP-TAZ and 95.4% for TDBP-TAZTO at 600 °C under N2 were observed. The major pyrolytic degradation products of TTBP-TAZ were formed in a single step and identified by FTIR analysis as 2,4,6-tribromophenol and further bromine-substituted aromatic compounds. In comparison, TDBP-TAZTO was pyrolytic degraded in two steps, whereby on the first step the release of hydrogen Bromide and 1,3,5-triallyl-1,3,5-triazine-2,4,6-trione could be detected. In the second minor step, isocyanic acid could be additionally identified. Subsequently, the obtained products of the TGA-FTIR measurements were used for a targeted search for mass fragments in mass spectrometry measurements. For TTBP-TAZ, only the degradation product 1,3,5-tribromobenzene could be detected by MS/MS analyzes. No comparable thermal degradation products, except hydrogen bromide, were observed in the MS/MS spectra of TDBP-TAZTO. Therefore, the search of further mass fragments was not possible compared to the findings of the TGA-FTIR measurements. KW - Pyrolysis KW - Thermal decomposition KW - TGA-FTIR KW - Mass spectrometry PY - 2019 DO - https://doi.org/10.1016/j.jaap.2019.104635 VL - 141 SP - 104635-1 EP - 104635-5 PB - Elsevier B.V. AN - OPUS4-48506 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike T1 - Harmonization in microplastics Analysis N2 - The lecture summarizes the current status of hamonization edr microplastics analytics in Germany. T2 - Symposium on Occurrence and Fate of Microplastics CY - Beijing, China DA - 09.07.2019 KW - Microplastics KW - TED-GC-MS KW - Harmonisation PY - 2019 AN - OPUS4-49063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike T1 - Plastik im Boden, Aktueller Forschungsstand N2 - Der Vortrag gibt einen Überblick über ein laufendes Vorhaben zum Thema Mikroplastik in Böden. T2 - NUA-Veranstaltung "Plastik in Natur und Umwelt" CY - Münster, Germany DA - 08.03.2019 KW - Mikroplastik KW - Böden KW - Analytik PY - 2019 AN - OPUS4-47579 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike T1 - Harmonisierung von Untersuchungsverfahren für (Mikro-)Plastik in der Umwelt N2 - Im Rahmen der Thematik "Recycling von Kunststoffen" wird die Thematik "Mikroplastik" vorgestellt T2 - Berliner Recycling- und Rohstoffkonferenz CY - Berlin, Germany DA - 11.03.2019 KW - Mikroplastik KW - Standarisierung KW - Analytik PY - 2019 AN - OPUS4-47582 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike T1 - About Standardization and Analytics of Microplastics N2 - Presentation about national and international standardization of microplastic analysis, as well as the project RUSEKU T2 - Industrievereinigung Chemiefaser e.V. CY - Frankfurt, Germany DA - 26.02.2019 KW - Standardisation KW - Microplastic KW - Analysis PY - 2019 AN - OPUS4-47577 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike T1 - Mikroplastik in der Umwelt und im Trinkwasser: Einordnung der Relevanz und der Methodik N2 - Überblick zur Thematik Mikroplastik mit speziellem Fokus auf Trinkwasser T2 - 20. Jahrestagung Trinkwasserringversuche Nordrhein-Westfalen – Niedersachsen CY - Osnabrück, Germany DA - 06.03.2019 KW - Trinkwasser KW - Umwelt KW - Mikroplastik PY - 2019 AN - OPUS4-47578 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dittmann, Daniel A1 - Ruhl, A. S. A1 - Jekel, M. A1 - Braun, Ulrike T1 - Spurenstoffadsorption an Aktivkohle – Untersuchungen mit Analysen oberhalb des Siedepunktes N2 - In diesem Beitrag wird gezeigt wie mit Thermogravimetrischen Analysen (TGA) Aktivkohleoberflächen charakterisiert werden können. Außerdem wie TGA mit Zersetzungsgasanalyse zur Untersuchung von Adsorbat-Systemen (Carbamazepin an drei verschiedenen Aktivkohlen) zur Aufklärung von Adsorptionszuständen genutzt werden kann. T2 - Wasser 2019 CY - Erfurt, Germany DA - 27.05.2019 KW - Aktivkohle KW - Adsorption KW - Carbamazepin KW - Thermogravimetrie PY - 2019 SN - 978-3-947197-11-8 SP - 98 EP - 102 AN - OPUS4-48258 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dümichen, Erik A1 - Eisentraut, Paul A1 - Celina, M. A1 - Braun, Ulrike T1 - Automated thermal extraction-desorption gas chromatography mass spectrometry: A multifunctional tool for comprehensive characterization of polymers and their degradation products N2 - The TED-GC-MS analysis is a two-step method. A sample is first decomposed in a thermogravimetric analyzer (TGA) and the gaseous decomposition products are then trapped on a solid-phase adsorber. Subsequently, the solid-phase adsorber is analyzed with thermal desorption gas chromatography mass spectrometry (TDU-GC-MS). This method is ideally suited for the analysis of polymers and their degradation processes. Here, a new entirely automated System is introduced which enables high sample throughput and reproducible automated fractioned collection of decomposition products. Strengths and limitations of the system configuration are elaborated via three examples focused on practical challenges in materials analysis and identification: i) separate analysis of the components of a wood-plastic-composite material, ii) quantitative determination of weight concentration of the constituents of a polymer blend and iii) quantitative analysis of model samples of microplastics in suspended particulate matter. KW - Thermal extraction-desorption gas chromatography mass spectrometry KW - Analysis KW - Polymers KW - Microplastics KW - Automation PY - 2019 DO - https://doi.org/10.1016/j.chroma.2019.01.033 VL - 1592 SP - 133 EP - 142 PB - Elsevier CY - Amsterdam AN - OPUS4-48287 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -