TY - CONF A1 - Meurer, Maren T1 - Is olypropylene relevant for microplastic analytics? N2 - Nowadays, in every terrestrial and aquatic ecosystem, even in the remotest areas, small residues of plastics, the so called microplastic (MP) can be found. MPs are particles with a size of 1-1000 µm (ISO/TR 21960:2020), mainly containing synthetic polymers like polyethylene (PE), polypropylene (PP), polystyrene (PS) or polyethylene terephthalate (PET). Even styrene-butadiene rubber (SBR) as an indication for tire wear is included due to similar particle formation. To understand the MPs consequences to the environment, it is of high priority to capture its extent of contamination. It is surprising that in the analysis of polymer masses in environmental samples, PE, PS and SBR are often detected, but only small amounts of PP, although this is the second most commonly produced standard plastic and many MP particles originate from carelessly disposed packaging materials. This presentation provides hypotheses about the reasons of rare PP identification and mass quantification in environmental samples. Different investigations of pristine PP and representative environmental samples, including the pre-treatment by Accelerated Solvent Extraction (ASE) or with density separation followed by the thermal extraction / desorption gas chromatography-mass spectrometry (TED-GC/MS) are presented. The results are discussed according to the material properties and a possible degradation mechanism under different weathering conditions which indicate less stability under relevant storage conditions. T2 - Society of Environmental Toxicology and Chemistry CY - Dublin, Ireland DA - 30.04.2023 KW - Sample preparation KW - Polypropylene KW - Microplastic KW - Degradation PY - 2023 AN - OPUS4-57474 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Radunz, Sebastian A1 - Kraus, Werner A1 - Bischoff, F. A. A1 - Emmerling, Franziska A1 - Resch-Genger, Ute A1 - Tschiche, Harald T1 - Temperature- and Structure-Dependent Optical Properties and Photophysics of BODIPY Dyes N2 - We report on the temperature- and structural-dependent optical properties and photophysics of a set of boron dipyrromethene (BODIPY) dyes with different substitution patterns of their meso-aryl subunit. Single-crystal Xray diffraction analysis of the compounds enabled a classification of the dyes into a sterically hindered and a unhindered group. The steric hindrance refers to a blocked rotational motion of the aryl subunit around the bond connecting this moiety to the meso-position of the BODIPY core. The energy barriers related to this rotation were simulated by DFT calculations. As follows from the relatively low rotational barrier calculated to about 17 kcal/mol, a free rotation is only possible for sterically unhindered compounds. Rotational barriers of more than 40 kcal/mol determined for the sterically hindered compounds suggest an effective freezing of the rotational motion in These molecules. With the aid of temperature-dependent spectroscopic measurements, we could show that the ability to rotate directly affects the optical properties of our set of BODIPY dyes. This accounts for the strong temperature dependence of the fluorescence of the sterically unhindered compounds which show a drastic decrease in fluorescence quantum yield and a significant shortening in fluorescence lifetime upon heating. The optical properties of the sterically hindered compounds, however, are barely affected by temperature. Our results suggest a nonradiative deactivation of the first excited singlet state of the sterically unhindered compounds caused by a conical intersection of the potential energy surfaces of the Ground and first excited state which is accessible by rotation of the meso-subunit. This is in good agreement with previously reported deactivation mechanisms. In addition, our results suggest the presence of a second nonradiative depopulation pathway of the first excited singlet state which is particularly relevant for the sterically hindered compounds. KW - Fluorescence KW - Sensor KW - Switch KW - pH KW - BODIPY KW - Dye KW - Probe KW - Synthesis KW - Photophysics KW - Mechanism PY - 2020 DO - https://doi.org/10.1021/acs.jpca.9b11859 SN - 1089-5639 VL - 124 IS - 9 SP - 1787 EP - 1797 PB - American Chemical Society AN - OPUS4-50639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Olivera, Paulo A1 - Michalchuk, Adam A1 - Marquardt, Julien A1 - Feiler, Torvid A1 - Prinz, Carsten A1 - Torresi, R. A1 - Camargo, P. A1 - Emmerling, Franziska T1 - Investigating the role of reducing agents on mechanosynthesis of Au nanoparticles N2 - Control over the bottom up synthesis of metal nanoparticles (NP) depends on many experimental factors, including the choice of stabilising and reducing agents. By selectively manipulating these species, it is possible to control NP characteristics through solution-phase synthesis strategies. It is not known, however, whether NPs produced from mechanochemical syntheses are governed by the same rules. Using the Au NPs mechanosynthesis as a model system, we investigate how a series of common reducing agents affect both the reduction kinetics and size of Au NPs. It is shown that the relative effects of reducing agents on mechanochemical NP synthesis differ significantly from their role in analogous solution-phase reactions. Hence, strategies developed for control over NP growth in solution are not directly transferrable to environmentally benign mechanochemical approaches. This work demonstrates a clear need for dedicated, systematic studies on NP mechanosynthesis. KW - Mechanochemistry KW - Metal nanoparicels PY - 2020 DO - https://doi.org/10.1039/d0ce00826e VL - 22 IS - 38 SP - 6261 EP - 6267 PB - Royal Society of Chemistry AN - OPUS4-51757 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kulla, Hannes A1 - Haferkamp, Sebastian A1 - Akhmetova, Irina A1 - Röllig, Mathias A1 - Maierhofer, Christiane A1 - Rademann, Klaus A1 - Emmerling, Franziska T1 - In situ investigations of mechanochemical one-pot syntheses N2 - We present an in situ triple coupling of synchrotron X-ray diffraction with Raman spectroscopy, and thermography to study milling reactions in real time. This combination of methods allows a correlation of the structural evolution with temperature information. The temperature information is crucial for understanding both the thermodynamics and reaction kinetics. The reaction mechanisms of three prototypical mechanochemical syntheses, a cocrystal formation, a C@C bond formation (Knoevenagel condensation), and the formation of a manganese-phosphonate, were elucidated. Trends in the temperature development during milling are identified. The heat of reaction and latent heat of crystallization of the product contribute to the overall temperature increase. A decrease in temperature occurs via release of, for example, water as a byproduct. Solid and liquid intermediates are detected. The influence of the mechanical impact could be separated from temperature effects caused by the reaction. KW - In situ studies KW - Mechanochemistry KW - Raman spectroscopy KW - Thermography KW - X-ray diffraction PY - 2018 DO - https://doi.org/10.1002/anie.201800147 SN - 1433-7851 SN - 1521-3773 VL - 57 IS - 20 SP - 5930 EP - 5933 PB - Wiley-VCH CY - Weinheim AN - OPUS4-44946 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haferkamp, Sebastian A1 - Emmerling, Franziska T1 - Insights into the mechanochemical Knoevenagel condensation N2 - Mechanochemistry paves the way to simple, fast, and green syntheses, but there is a lack in understanding of the underlying mechanisms. Here, we present a universal strategy for simultaneous real-time in situ analysis, combining X-ray diffraction, Raman spectroscopy, and thermography. T2 - Bessy User Meeting 2019 CY - Berlin, Germany DA - 05.12.2019 KW - Mechanochemistry PY - 2019 AN - OPUS4-50122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - May, Anastasia T1 - Thermomechanochemical Synthesis of Pimelic Acid Cocrystals N2 - Milling temperature is a critical factor in mechanochemistry, affecting the kinetics and outcomes of reactions. In the context of cocrystallization, the influence of milling temperature on the process has been investigated for cocrystal systems pyrazinamide:pimelic acid (PZA:PA) and 4,4'-bipyridine:pimelic acid (BPY:PA). By means of temperature-controlled milling, stabilization of metastable polymorph of PZA:PA was achieved, thereby decelerating the aging process of the polymorph. This was accomplished through controlled heated milling of PZA and PA. Furthermore, we have successfully synthesized all three BPY:PA polymorphs by mechanochemistry involving controlled cooled and heated milling. In previous studies, only the most stable polymorph was obtained by mechanochemistry. T2 - 10th European Crystallography School CY - Ohrid, North Macedonia DA - 23.06.2025 KW - Mechanochemistry KW - Cocrystal PY - 2025 AN - OPUS4-63797 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Al-Terkawi, Abdal-Azim A1 - Scholz, G. A1 - Emmerling, Franziska A1 - Kemnitz, E. T1 - Strontium-coordination polymers based on tetrafluorophthalic and phthalic acids: mechanochemical synthesis, ab initio structures determination, and spectroscopic characterization N2 - Two strontium-based dicarboxylate systems [Sr(oBDC-F4)(H2O)2] (1) and [{Sr(oBDC)(H2O)2)·H2O] (2) were synthesized mechanochemically via milling of Sr(OH)2·8H2O with tetrafluorophthalic acid (H2oBDC-F4) or phthalic acid (H2oBDC), respectively. The new structures were determined ab initio from the powder X-ray diffraction (PXRD) data. Both compounds 1 and 2 crystallize in the monoclinic space group P21 /c as two-dimensional coordination polymers (2D-CPs). The determined structures were validated by extended X-ray absorption (EXAFS) data. Compounds 1 and 2 show different thermal stabilities. The fluorinated CP 1 is decomposed at 300 °C while the nonfluorinated CP 2 transforms into a new phase after thermal treatment at 400 °C. The two hydrated CPs exhibit small surface areas which increase after the thermal posttreatment for 1 but remains unchanged for the dehydrated sample of 2. Dynamic vapor sorption (DVS) experiments indicate that both the dehydrated and hydrated samples of 2 depict no significant differences in their adsorption isotherms. The DVS of water indicates that the phase transition after thermal posttreatment of 2 is irreversible. KW - Mechanochemistry KW - XRD KW - NMR PY - 2017 DO - https://doi.org/10.1039/c7dt02564e SN - 1477-9226 SN - 1477-9234 VL - 46 IS - 37 SP - 12574 EP - 12587 PB - The Royal Society of Chemistry CY - Cambridge AN - OPUS4-42261 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heilmann, Maria T1 - Synthesis of bimetallic nickel nanoparticles as catalysts for the Sabatier reaction N2 - Nanoparticles (NPs) have become important materials for a variety of chemical technologies. The enhanced surface-area-to-volume ratio of NPs, making them excellent for use as catalyst, in analytical assays, and for antimicrobial applications. Nickel NPs have exhibited immense potential as important catalyst for the Sabatier reaction, i.e. converting waste to energy via transformation of CO2 into CH4, and could replace the rare earth elements such as Ru, PT, or Rh. In this work we describe the solvothermal synthesis of monometallic and bimetallic nickel nanoparticles. Monodisperse monometallic Ni NPs were synthesized using Oleylamin as solvent and reducing agent. The nanoparticles were investigated using small angle scattering (SAXS), scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDX), showing that the NPs are stable while the surface is not entirely covered. However, Ni has a high propensity to undergo oxidation, and becoming deactivated by coke formation. Hence, we further explore the preparation of bimetallic NPs, where a second metal is added to stabilize the Ni. Bimetallic Cu-Ni NPs were synthesized by simultaneous solvothermal reduction. These bimetallic NPs exhibit excellent catalytic properties are promising candidates to be used as catalysts for efficient energy storage. T2 - Adlershofer Forschungsforum 2019 CY - Berlin, Germany DA - 11.11.2019 KW - Nanoparticles KW - Catalysis KW - Synthesis PY - 2019 AN - OPUS4-50173 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tuma, Dirk A1 - Mady, A. H. A1 - Baynosa, M. L. A1 - Saad, M. A1 - Dhakal, G. A1 - Kim, W. K. A1 - Shim, Jae-Jin T1 - Morphology-engineered hollow NiTiO₃/C–Ag/Ag₃PO₄ S-scheme heterojunction photocatalyst: mechanistic insights into sunlight-driven tetracycline degradation N2 - Tetracycline (TCH), a widely used antibiotic, persists in aquatic and terrestrial environments, posing ecological risks and accelerating antibiotic resistance. To address this, we report a hollow-structured NiTiO₃/C–Ag/Ag₃PO₄ (NT/C–AAP) photocatalyst—the first hollow-type nickel titanate—synthesized via a self-template solvothermal route followed by photodeposition. The catalyst integrates key design strategies—hollow architecture, oxygen vacancies, carbon coating, and an S-scheme heterojunction—to optimize photocatalytic performance. The hollow structure enhances light harvesting via internal scattering, oxygen vacancies facilitate O2 adsorption and superoxide (O₂•⁻) generation, and the S-scheme heterojunction effectively suppresses electron–hole recombination while preserving strong redox potential. NT/C–AAP achieved 96% TCH degradation within 1 h and 82% mineralization in 3 h under solar light, far exceeding core–shell (18%) and aggregated (47%) NiTiO₃-based catalysts. Complete removal was realized within 40 min under 400 W visible light. The catalyst maintained 96% activity after five cycles, confirming excellent durability. Compared with previously reported NiTiO₃ photocatalysts, NT/C–AAP delivered a 50–400% performance enhancement arising from its engineered hollow structure and improved electronic properties. Mechanistic studies identified O₂•⁻ and •OH radicals as dominant species, validating the role of morphology and interface engineering in directing charge separation and redox activity. Additionally, a catalyst performance index was proposed to facilitate comparison across diverse conditions. Overall, this work introduces a novel, durable photocatalyst that links structural design to functional performance and demonstrates strong potential for practical environmental remediation. KW - Heterojunction photocatalyst KW - Photodegradation KW - Tetracycline PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655946 DO - https://doi.org/10.1007/s42114-025-01600-x SN - 2522-0128 VL - 9 IS - 2 SP - 1 EP - 19 PB - Springer Nature CY - London AN - OPUS4-65594 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwibbert, Karin A1 - de Eulate Pérez, Elisa García A1 - Wen, Keqing A1 - Voss, Heike A1 - Thiele, Dorothea A1 - Richter, Anja M. A1 - Bonse, Jörn T1 - Escherichia coli repellence via laser-induced periodic surface structures (LIPSS) on titanium: Critical role of biofilm-associated gene expression N2 - The inconsistency in the observed bacteria-repellent effects of laser-induced surface textures remains a subject of scientific debates. With E. coli TG1 as test strain, we performed biofilm formation assays on ultrashort pulse laser textured titanium. Samples covered with low spatial frequency LIPSS (LSFL) of periods around 750 nm or with high spatial frequency LIPSS (HSFL) featuring smaller periods around 100 nm were processed on polished samples. While LSFL significantly reduce the number of adhering bacteria compared to the polished reference, HSFL do not. Simultaneously, we concentrate our study on bacterial strategies employed for biofilm formation, that is the transcription of the biofilm-associated genes csgB, involved in primary adhesion to a surface, and wza, participating in biofilm maturation. Promoter regions of these genes were cloned into a promotor probe plasmid with the green fluorescent protein GFP+ as reporter and transferred into the test strain. As indicated by the fluorescence intensity of the reporter protein, among the bacteria colonizing LSFL-covered areas, a markedly higher proportion of cells transcribing csgB or wza were detected, compared to the bacterial populations colonizing the polished or HSFL-covered areas. To our knowledge, this is the first study indicating that the antifouling effect of LSFL topographies can be counteracted when bacteria activate biofilm-associated genes. KW - Laser-induced periodic surface structures (LIPSS) KW - Titanium KW - Biofilm KW - Antifouling KW - Gene expression KW - Fluorescence microscopy PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655572 DO - https://doi.org/10.1016/j.apsusc.2026.166363 SN - 0169-4332 VL - 730 SP - 1 EP - 9 PB - Elsevier B.V. AN - OPUS4-65557 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gugin, Nikita A1 - Villajos Collado, José Antonio A1 - Dautain, O. A1 - Maiwald, Michael A1 - Emmerling, Franziska T1 - Optimizing the Green Synthesis of ZIF-8 by Reactive Extrusion Using In Situ Raman Spectroscopy N2 - We report the scale-up of a batch solid synthesis of zeolitic imidazolate framework-8 (ZIF-8) for reactive extrusion. The crystalline product forms in the extruder directly under the mixture of solid 2-methylimidazole and basic zinc carbonate in the presence of a catalytic amount of liquid. The process parameters such as temperature, liquid type, feeding rate, and linker excess were optimized using the setup specifically designed for in situ Raman spectroscopy. Highly crystalline ZIF-8 with a Brunauer–Emmett–Teller (BET) surface area of 1816 m2 g–1 was quantitatively prepared at mild temperature using a catalytic amount of ethanol and a small excess of the linker. Finally, we developed a simple and comprehensive approach to evaluating the environmental friendliness and scalability of metal–organic framework (MOF) syntheses in view of their large-scale production. KW - Mechanochemistry KW - In situ Raman KW - Large-scale processing KW - Metal−organic frameworks KW - Twin-screw extrusion (TSE) PY - 2023 DO - https://doi.org/10.1021/acssuschemeng.2c07509 SN - 2168-0485 VL - 11 IS - 13 SP - 5175 EP - 5183 PB - ACS Publications AN - OPUS4-57366 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Božičević, Lucija A1 - Altmann, Korinna A1 - Hildebrandt, Jana A1 - Knigge, Xenia A1 - Vrček, Valerije A1 - Peranić, Nikolina A1 - Kalcec, Nikolina A1 - Vinkovic Vrcek, Ivana T1 - Estrogenic activity of plastic nanoparticles mixture under in vitro settings N2 - The plastic value chain, central part of modern living, caused environmental pollution and bioaccumulation of plastic nanoparticles (PNPs). Their ubiquitous presence in different environmental and biological compartments has become a serious threat to human health and ecosystems. Frequently used plastic materials such as polypropylene (PP), polystyrene (PS) and polyethylene (PE) have been detected in the form of PNPs in the food chain, soil, water and air, as well as in human feces and blood. In this study, we aimed to provide novel insights in endocrine disrupting properties of PNPs using in vitro estrogen receptor (ER) transactivation assay. The effects of PP-NPs, PE-NPs and PS-NPs and their mixture on T47D-KBluc cell line stably transfected with luciferase as reporter enzyme was evaluated by means of cytotoxicity, cellular uptake and ER activation. Tested dose range for PNPs was 0.001 – 10 mg/L. Both cellular uptake and cytotoxicity for all PNPs was found to be dose-dependent. Only the highest dose of PP-NPs and PE-NPs induced apoptosis and cell death, while PS-NPs were not cytotoxic in tested dose range. For tested concentrations, PP-NPs and PE-NPs showed significant agonistic activity on ER, while PS-NPs cannot be considered ER active. When, applied as mixture, PNP demonstrated additive toxicity effects compared to the effect of each individual PNPs. Additivity was also observed for ER agonistic effect of PNPs mixture according to the benchmark dose-addition modelling approach. This study provides missing science-based evidence on endocrine disrupting effects of PE-NPs, PP-NPs, PS-NPs and their mixtures and highlights the importance of considering unintentional, aggregate and combined exposure to different PNPs in risk management. KW - Risk assessment KW - Nanoplastics KW - Estrogenic activity of plastic nanoparticles PY - 2024 DO - https://doi.org/10.1039/D3EN00883E SN - 2051-8153 VL - 11 IS - 5 SP - 2112 EP - 2126 PB - Royal Society of Chemistry (RSC) AN - OPUS4-59724 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lee, P.-W. A1 - Kaynak, T. A1 - Al-Sabbagh, Dominik A1 - Emmerling, Franziska A1 - Schalley, C. T1 - Effect of Perfluorinated Side-Chain Length on the Morphology, Hydrophobicity, and Stability of Xerogel Coatings N2 - Superhydrophobic surfaces can be quickly formed with supramolecular materials. Incorporating low-molecular-weight gelators (LMWGs) with perfluorinated chains generates xerogel coatings with low surface energies and high roughness. Here, we examine and compare the properties of the xerogel coatings formed with eight different LMWGs. These LMWGs all have a trans-1,2-diamidocyclohexane core and two perfluorinated ponytails, whose lengths vary from three to ten carbon atoms (CF3 to CF10). Investigation of the xerogels aims to provide in-depth information on the chain length effect. LMWGs with a higher degree of fluorination (CF7 to CF10) form superhydrophobic xerogel coatings with very low surface energies. Scanning electron microscopy images of the coatings show that the aggregates of CF5 and CF7 are fibrous, while the others are crystal-like. Aggregates of CF10 are particularly small and further assemble into a porous structure on the micrometer scale. To test their stabilities, the xerogel coatings were flushed multiple times with a standardized water flush test. The removal of material from the surface in these flushes was monitored by a combination of the water contact angle, contact angle hysteresis, and coating thickness measurements. A new method based on image processing techniques was developed to reliably determine the change of the coating thickness. The CF7, CF9, and CF10 surfaces show consistent hydrophobicity and coating durability after repetitive flushing tests. The length of the perfluorinated side chains thus has a significant effect on the morphology of the deposited xerogel coatings, their roughness, and, in consequence, their hydrophobicity and mechanical durability. KW - Coating materials KW - Amorphous materials KW - Hydrophobicity KW - Materials Stability PY - 2021 DO - https://doi.org/10.1021/acs.langmuir.1c02341 SN - 1520-5827 VL - 37 IS - 49 SP - 14390 EP - 14397 PB - ACS Publications AN - OPUS4-54071 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmitt, M. A1 - Altmann, Korinna A1 - Fengler, Petra A1 - Gehde, M. T1 - Air-based polyethylene fragmentation with high yield to form microplastic particles as reference material candidates N2 - Microplastic particles with sizes between 1 to 1000 μm are widely distributed worldwide. Origin, transport pathways and fate are poorly known, as sampling, sample preparation and detection methods are major challenges. In addition, reference materials that mimic environmental particles are lacking. Most challenging is the yield of MP particle production and the need for resource-intensive grinding with liquid nitrogen. In this paper, a machine is designed to produce aged microplastic particles as reference material candidates with high yield. The machine is based on ultraviolet aging of a thin foil and mechanical fragmentation using clean air. An example of aging and fragmentation of high density polyethylene with additional physical and chemical characterization of shape, size, aging state by carbonyl index and density is presented. KW - Microplastics KW - Degradation of polyethylene KW - Air fragmentation KW - Microplastics reference material PY - 2023 DO - https://doi.org/10.1002/appl.202200121 SP - 1 EP - 18 PB - Wiley online library AN - OPUS4-57203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weber, Simone T1 - Influence of the pH Value to the Degradation of Ester-Based Thermoplastic Polyurethanes N2 - Microplastics are solid polymeric particles with a size of 1-1000 μm (ISO/TR21960:2020), which can be emitted from mismanaged waste into the environment, where microplastic is now ubiquitous. What happens to the microplastics after ending up in the environment, which risks entail and what effects it has are not sufficiently clarified up to now. The most certain issue is that the plastic particles in the environment are exposed to natural ageing, are fragmenting and degrading, such that the potential risk to ecosystems and humans is increasing due to the formation of smaller and smaller particles, potentially even including nanoplastics, if these are ingested before their further degradation. Therefore, and in view of a possible registration of polymers under REACH in the future, it is necessary to investigate the degradation of thermoplastic polyurethanes (TPU) regarding hydrolysis stability to evaluate possible risks and effects to the environment. In the present studies, one thermoplastic polyurethane – with and without hydrolysis stabilizer – is exposed to different pH buffers at 50°C for 14 days to investigate hydrolysis depending to different pH values (acid, alkali and neutral) based on OECD guideline TG111. The hydrolysis behavior of the TPUs is characterized by surface sensitive techniques and on bulk properties. First degradation effects can be detected by SEC. Hydrolysis, especially under acidic and basic conditions, leads to chain scissions to lower molecular masses. Furthermore, the degradation products which indicate the structure of the bulk material were detected by thermo-analytical methods like TGA-FTIR for the small degradation products and the thermo extraction/desorption-gaschromatography/mass spectrometry (TED-GC/MS) for bigger degradation products. Acidic and basic hydrolysis shows the same degradation behavior which is caused by a preferred scission of the ester and urethane functionalities. Surface-sensitive techniques such as XPS demonstrate less carboxylic acid formation at acidic than at alkaline pH value in the TPU without stabilator, where as the TPU with stabilator ages to the same extent in both pH ranges. Altogether, the hydrolysis of TPUs – independently of added stabilizer or not – in acid and alkali environment is accelerated compared to the neutral hydrolysis. T2 - SETAC CY - Dubin, Ireland DA - 30.04.2023 KW - Degradation KW - Thermoplastic Polyurethane KW - Microplastic KW - Polymer Hydrolysis KW - Polymer 3R KW - REACH PY - 2023 AN - OPUS4-58906 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wiesner, Yosri T1 - Erfassung von Degradationsprodukten und Additiven sowie temperaturspezifische Pyrolyseprodukte mittels TED-GC/MS N2 - Im der Präsentation werden, neben der Möglichkeit der Mikroplastikquantifizierung, auf weitere Anwendungsfelder der Methode TED-GC/MS eigegangen. Dies beinhaltet die Erfassung von Degradationsprodukten UV/O2 geschädigter Polymere und die Detektion von Additiven. Die Optimierung der Methode betreffend Messzeit und materialspezifischer Messanforderung sind ebenfalls Gegenstand. T2 - Kolloquium Massenspektrometrie von Polymeren CY - Berlin, Germany DA - 09.05.2023 KW - TED-GC/MS KW - Polymere KW - Degradation KW - Additive PY - 2023 AN - OPUS4-57480 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Moss, Caitlin T1 - Mechanochemistry as a Green Synthetic Route N2 - Mechanochemistry has emerged as a transformative approach in sustainable chemistry, offering a solvent-free and energy-efficient pathway for chemical synthesis. By utilizing mechanical force—typically through ball milling, grinding, or other shear-driven methods, reactions can proceed without the extensive use of harmful solvents, reducing waste and environmental impact. This poster explores the principles, methodologies, and applications of mechanochemistry in developing greener synthetic routes, with a focus on pharmaceutical and materials science applications. Key advantages, including reduced reaction times, enhanced selectivity, and improved atom economy, will be highlighted alongside challenges such as scalability. By presenting mechanochemistry as a frontier technology at the intersection of chemistry, materials science, and environmental stewardship, this work invites dialogue among students and academics about its future in sustainable innovation. T2 - Furture WINS 2024 CY - Berlin, Germany DA - 21.11.2024 KW - Mechanochemistry KW - Green chemistry PY - 2024 AN - OPUS4-62123 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heinekamp, Christian T1 - Synthesis of zirconiumfluorides using a sol-gel/postfluorination approach and their application in C-F bond activation N2 - ZrF4 species have shown to exhibit hard Lewis acidity in homogeneous systems. In order to study solid state Lewis acidic ZrF4 a sol-gel synthesis was adapted following previous approaches for AlF3 and a necessary post fluorination is being optimised to obtain a Lewis acidic heterogeneous catalyst for C-F bond activation. The influence of different Zr precursors was also studied while the local coordination sphere of a active species was found to be similar to β-ZrF4 using EXAFS of the Zr K-edge. T2 - RSC Twitter Poster Conference 2023 CY - Online meeting DA - 28.02.2023 KW - ZrF4 KW - Heterogeneous catalysis PY - 2023 AN - OPUS4-57227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska T1 - Mechanochemical Syntheses of Metal Phosphonates N2 - Mechanochemistry is a suitable method for synthesizing a variety of metal phosphonates. By varying the ratio of the reactants, it is possible to control the reaction pathway. With this approach targeted synthesis of a certain composition is possible. Several new metal phosphonate structures were solved from the powder X-ray diffraction data including molecular metal phosphonates. The results demonstrate a new fast, facile, and environmental friendly alternative for the preparation of metal phosphonates. In situ investigations of the milling processes provided insights into the formation process of metal phosphonates. A multi-step diffusion mechanism was identified for most systems. Crystalline phases were obtained intermediately, suggesting that the synthesis is following Ostwald’s rules of stages. T2 - 1st European Workshop on Metalphophantes CY - Swanse, UK DA - 18.09.2018 KW - Mechanochemistry PY - 2018 AN - OPUS4-46382 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zauer, M. A1 - Prinz, Carsten A1 - Adolphs, J. A1 - Emmerling, Franziska A1 - Wagenführ, A. T1 - Sorption surfaces and energies of untreated and thermally modified wood evaluated by means of excess surface work (ESW) N2 - Water vapor sorption surface areas and sorption energies of untreated and thermally modified Norway spruce [Picea abies (L.) Karst.], sycamore maple (Acer pseudoplatanus L.) and European ash (Fraxinus excelcior L.) were investigated by means of dynamic vapor sorption (DVS) measurements and excess surface work (ESW) evaluation method, respectively. Adsorption and desorption experiments in the hygroscopic range and desorption tests from water saturation were conducted. Thermodynamically, ESW is the sum of the surface free energy and the isothermal isobaric work of sorption. From the amount adsorbed in the first Minimum a specific surface area similar to the BET surface area can be obtained. The results show that untreated spruce has a significantly higher specific water vapor Sorption surface and sorption energy compared to both hardwoods maple and ash. Thermal modification of the woods leads to a significant reduction of water vapor Sorption surface and sorption energy. The determined surface area and energy are higher in desorption direction than in adsorption direction, whereby the highest values in Desorption direction from water saturation, especially for maple and ash, were obtained. The surface areas calculated by means of the ESW method are similar to the surface areas calculated by means of the BET method, particularly in adsorption direction. KW - Excess surface work KW - Dynamic vapor sorption KW - Wood KW - BET PY - 2018 DO - https://doi.org/10.1007/s00226-018-1021-2 SN - 1432-5225 SN - 0043-7719 VL - 52 IS - 4 SP - 957 EP - 969 PB - Springer CY - Berlin Heidelberg AN - OPUS4-44975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -