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- ItemComparison of the molecular properties and morphology of polypropylenes irradiated under different atmospheres and after annealing(Hoboken, NJ [u.a.] : Wiley InterScience, 2006) Krause, Beate; Häußler, Liane; Voigt, DieterElectron-beam irradiation, a well-known way of generating long-chain branching, was used to modify polypropylene. Samples were investigated with differential scanning calorimetry, polarized light microscopy, and size exclusion chromatography. Independently of the atmosphere, postannealing led to the deactivation of residual radicals and to the reduction of the nucleus density. In comparison with the initial polypropylene, the crystallization temperatures increased for nonannealed samples but decreased for annealed samples. Stable products were obtained only by irradiation in nitrogen followed by annealing. A reaction including free radicals with oxygen in the ambient atmosphere led to increasing molar mass degradation and the formation of long-chain branching after Storage. © 2006 Wiley Periodicals, Inc.
- ItemUntersuchung neuartiger kombinierter Vernetzungsmechanismen für die Pulverlackhärtung unter Einfluss von Katalysatoren, Teilprojekt 1/Teil 1; Untersuchungen zur thermischen und katalysierten Spaltung von Uretdionen als verkappungsmittelfrei blockierte Isocyanate, Teilprojekt 1/Teil 2; Einfluss von Additiven und Pigmenten auf die Grenzflächenphänomene bei der Pulverlackbeschichtung, Teilprojekt 2/Teil 3 : Abschlussbericht Teil 1 - 3 zum Teilprojekt 1 - 2 im Rahmen des F und E-Programmes zur Erweiterung der Anwendung der Pulverlackiertechnik(Dresden : Leibniz-Institut für Polymerforschung, 2000) Gedan-Smolka, Michaela; Meier Haack, Jochen; Lehmann, Frank; Grundke, Karina; Uhlmann, Petra; Wulf, Martin[no abstract available]
- ItemSubstratinduzierte Veränderungen von Zellen im Kontakt mit Polymermaterialien : Schlussbericht(Dresden : Institut für Polymerforschung Dresden, 2002) IPF[no abstract available]
- ItemCharakterisierung und Optimierung von Nano-Templaten aus Polymeren : bmb+f-Förderschwerpunkt Kondensierte Materie, Großgeräte der physikalischen Grundlagenforschung ; Schlussbericht(Hannover : Technische Informationsbibliothek (TIB), 2004) Stamm, Manfred; Sydorenko, A.; Minko, S.; Tokarev, I.; Křenek, R.[no abstract available]
- ItemInvestigation of changes in crystalline and amorphous structure during deformation of nano-reinforced semi-crystalline polymers by space-resolved synchrotron saxs and waxs(Amsterdam : Elsevier, 2009) Schneider, K.; Schone, A.; Jun, T.-S.; Korsunsky, A.M.Complex structural changes occur in semi-crystalline polymers during deformation. In (nano-)filled systems the situation becomes even more complicated, since not only phase changes may take place, but also local (interfacial) failure between phases may occur. To help identify specific processes taking place within these systems, simultaneous small- and wide-angle X-ray scattering (SAXS/WAXS) measurements were performed using synchrotron radiation during in situ deformation. Using a highly focused beam, spatially resolved local information can be extracted by scanning the beam across the deformed/damaged region within the sample. The characteristic changes in the different phases are presented and discussed. While the study of WAXS patterns gives insight into the orientation and dimensions of the crystallites, SAXS provides information about the mutual arrangement of phases and the interfacial failure phenomena. Based on the analysis of the results obtained in our experiments it will be shown that the first changes in the crystalline phase appear long before macroscopic yielding of the sample is reached, i.e. the onset of irreversible deformation takes place. In the post-yield regime radical changes are observed in both the long- and short-range structures. It is concluded that the presence of nano-fillers exerts a strong influence on the establishment of microcrystalline structure, and hence also on the deformation behaviour at the microscopic scale.
- ItemGrundlegende Untersuchungen zur Entwicklung von Hochtemperaturthermoplastblends mit verbesserter Phasenanbindung : Forschungsvorhaben auf dem Gebiet: "Exploratorische Materialforschung mit Nachwuchswissenschaftlerinnen und Nachwuchswissenschaftlern" ("Hot-Topics") ; Laufzeit: 04/2001 - 09/2002 ; Abschlußbericht(Dresden : Leibniz-Institut für Polymerforschung, 2003) Pospiech, Doris; Hoffmann, Thorsten; Altstädt, Volker[no abstract available]
- ItemChemisches Verfahren zur Herstellung von Kunststoffformteilen mit beflockten Oberflächen als Einstoffsystem auf der Basis von Polyamid : gemeinsamer Schlussbericht für den Zeitraum: 01.10.2005 - 31.07.2008(Dresden : Leibniz-Institut für Polymerforschung, 2008) Lehmann, Dieter; Hoffmann, Gerald; Bahners, Thomas[no abstract available]
- ItemAdvances for the topographic characterisation of SMC materials(Basel : MDPI, 2009) Calvimontes, A.; Grundke, K.; Müller, A.; Stamm, M.For a comprehensive study of Sheet Moulding Compound (SMC) surfaces, topographical data obtained by a contact-free optical method (chromatic aberration confocal imaging) were systematically acquired to characterise these surfaces with regard to their statistical, functional and volumetrical properties. Optimal sampling conditions (cut-off length and resolution) were obtained by a topographical-statistical procedure proposed in the present work. By using different length scales specific morphologies due to the influence of moulding conditions, metallic mould topography, glass fibre content and glass fibre orientation can be characterized. The aim of this study is to suggest a systematic topographical characterization procedure for composite materials in order to study and recognize the influence of production conditions on their surface quality. © 2009 by the authors.
- ItemVerbundprojekt Leichtbau mit thermoplastischen Nanocomposites (LB-Nanos) - Werkstoffentwicklung und -charakterisierung : Abschlussbericht(Hannover : Technische Informationsbibliothek (TIB), 2009) IPF[no abstract available]
- ItemRöntgen-Photoelektronenspektroskopie zur Charakterisierung der Zugänglichkeit und Reaktivität funktioneller Gruppen an Polymeroberflächen gegenüber großen Molekülen : Abschlussbericht zum BMBF-geförderten Forschungsprojekt(Hannover : Technische Informationsbibliothek (TIB), 2003) Simon, Frank; Frenzel, Ralf[no abstract available]