TY - RPRT A1 - Schlummer, Martin A1 - Wagenknecht, Udo A1 - Markowski, Jens T1 - Verkehrsfähige Polymer-Recyclate aus der Elektro(nik)altgeräteverwertung durch spektroskopische Sortierung und dichtebasierte Störstoffabtrennung N2 - Schlussbericht Projekt SpectroDense KW - Kunststoffabfall KW - Sortieren Y1 - 2011 PB - Fraunhofer IVV CY - Freising ER - TY - GEN A1 - Schlummer, Martin A1 - Arends, Dagmar A1 - Mäurer, Andreas A1 - Markowski, Jens A1 - Wagenknecht, Udo T1 - Characterisation and materials flow management for waste electrical and electronic equipment plastics from German dismantling centres T2 - Waste Management & Research N2 - Waste electrical and electronic equipment is a complex waste stream and treatment options that work for one waste category or product may not be appropriate for others. A comprehensive case study has been performed for plastic-rich fractions that are treated in German dismantling centres. Plastics from TVs, monitors and printers and small household appliances have been characterised extensively. Based on the characterisation results, state-of-the-art treatment technologies have been combined to design an optimised recycling and upgrade process for each input fraction. High-impact polystyrene from TV casings that complies with the European directive on the restriction of hazardous substances (RoHS) was produced by applying continuous density separation with yields of about 60%. Valuable acrylonitrile butadiene styrene/ polycarbonate can be extracted from monitor and printer casings by near- infrared-based sorting. Polyolefins and/or a halogen-free fraction of mixed styrenics can be sorted out by density separation from monitors and printers and small household appliances. Emerging separation technologies are discussed to improve recycling results. KW - Waste electrical and electronic equipment plastics KW - recycling, separation KW - characterisation, near-infrared Y1 - 2015 U6 - https://doi.org/10.1177/0734242x15588585 SN - 1096-3669 VL - 33 IS - 9 SP - 775 EP - 784 ER - TY - GEN A1 - Boldt, Regine A1 - Leuteritz, Andreas A1 - Schob, Daniela A1 - Ziegenhorn, Matthias A1 - Wagenknecht, Udo T1 - Barrier Properties of GnP–PA-Extruded Films T2 - Polymers N2 - It is generally known that significant improvements in the properties of nanocomposites can be achieved with graphene types currently commercially available. However, so far this is only possible on a laboratory scale. Thus, the aim of this study was to transfer results from laboratory scale experiments to industrial processes. Therefore, nanocomposites based on polyamide (PA) and graphene nanoplatelets (GnP) were prepared in order to produce membranes with improved gas barrier properties, which are characterized by reduced permeation rates of helium. First, nanocomposites were prepared with different amounts of commercial availably graphene nanoplatelets using a semi-industrial-scale compounder. Subsequently, films were produced by compression molding at different temperatures, as well as by flat film extrusion. The extruded films were annealed at different temperatures and durations. In order to investigate the effect of thermal treatment on barrier properties in correlation to thermal, structural, and morphological properties, the films were characterized by differential scanning calorimetry (DSC), wide angle X-ray scattering (WAXS), optical microscopy (OM), transmission electron microscopy (TEM), melt rheology measurements, and permeation measurements. In addition to structural characterization, mechanical properties were investigated. The results demonstrate that the permeation rate is strongly influenced by the processing conditions and the filler content. If the filler content is increased, the permeation rate is reduced. The annealing process can further enhance this effect. KW - graphene nanoplatelets KW - polyamide KW - nanocomposites KW - flat film extrusion KW - permeation rate Y1 - 2020 U6 - https://doi.org/10.3390/polym12030669 SN - 2073-4360 VL - 12 IS - 3 ER -