The present thesis deals with optimization of the formation of thin layers of metallic materials. In the theoretical part was elaborated overview of the implementation of the formation of thin- film structures, particularly using vacuum techniques. Chemical and physical vapor deposition. They were described methods of pretreatment of thin layers. The findings were discussed methods of controlling the pre-treated surface, quality control and mutual adhesion of coating layers. In the experimental part of the pre-treatment methods were selected and applied to selected substrates. Pretreatments were evaluated using a control surface by wetting angles and by atomic force microscopy. Then, the metal structure formed of copper on the pretreated substrates. Implementation by means of magnetron sputtering. Adhesion layers was checked by testing the surface lattice method. The quality was observed by scanning electron microscopy. The results were used to design the technological process of making metal layers.

Die Zielstellung dieser Dissertation besteht darin, einen Beitrag zur Charakterisierung sowohl der Ausgangsmaterialien (Naturfasern, Polymere) als auch ihrer Verbundeigenschaften zu leisten. Morphologische Unterschiede der Fasern, im wesentlichen bedingt durch Erntezeitpunkt, Röstdauer und Verarbeitungsbedingungen, haben Einfluss auf die mechanischen Kennwerte als auch auf das Faser/Matrix-Interface des Verbundwerkstoffs. Durch unterschiedliche Verfahren (Thermoanalyse, Ubbelohde-Viskosimetrie, NMR-Spektroskopie, Einzelfaserzugversuch) werden sowohl das Degradationsverhalten als auch die Prozessgrenzen bestimmt. Zur Einschätzung des Grenzflächenzustands werden oberflächensensitive Verfahren (BET-Verfahren, Zeta-Potentialbestimmung, IR-Spektroskopie, Rasterelektronen-mikroskopie) angewendet. Die Charakterisierung der durch Compoundieren und Spritzgießen, bzw. durch Konsolidieren von Hybridvliesen hergestellten Verbunde erfolgt mittels quasi-statischer bzw. dynamisch-mechanischer Methoden (DMA). Fraktographische rasterelektronenmikroskopische und IR-spektroskopische Untersuchungen belegen die Veränderung des Interfaces durch geeignete Faserbehandlung, Prozessparameter und Haftvermittlung. Die vorliegende Arbeit weist die effektive Verstärkungswirkung der Naturfasern Flachs bzw. Hanf in hochpolymeren Matrices zuverlässig nach. / The objectives of this dissertation are the characterization of the components (natural fibers, polymers) and the resulting properties of the composites. Due to differences in fiber morphology, mainly caused by the date of harvest, retting and fiber separation procedures, the mechanical properties and the fiber/matrix interface are effected. The degradation and the limits of the process are characterized by means of thermal analysis, Ubbelohde viscosimetry, NMR spectroscopy and single fiber tensile test. Surface sensitive methods (BET measurements, zeta potential measurements, IR-spectroscopy) were applied to evaluate the fiber/matrix interface. The composites were first manufactured by compounding and injection molding as well as by consolidation of hybrid nonwovens and characterized by means of quasi statical and dynamic-mechanical methods. The effect of adequate fiber treatements, process parameters and coupling agents becomes obvious applying fractographic SEM and IR spectroscopic measurements. The gained results indicate the strengthening effect of natural fibers like flax and hemp on the performance of high polymers.

In present study, high energy electrons were used to modify blends based on RP and PP under two conditions: stationary and in-stationary conditions. Modification of blend under stationary condition is a process which is established in industrial application and where required absorbed dose is applied to form parts (after molding) at room temperature and in solid state. On the contrary, the modification of blend with high energy electrons under in-stationary condition is a new process (electron induced reactive processing) where required absorbed dose is applied to a molten state during melt mixing process. The modification of blend based on RP and PP under stationary condition resulted in slightly enhancement of tensile properties while the modification of this blend under in-stationary condition resulted in deterioration of tensile properties due to degradation of the PP matrix. Thus, special grafting agent (GA) is required for improving the tensile properties. The effect of different GAs on tensile, thermal, dynamic mechanical as well as morphological properties and melt flow properties of blends based on RP and PP were determined. The optimum absorbed dose for modification of blend based on RP and PP under both conditions was evaluated. In addition, the effect of treatment parameters of electron induced reactive processing was investigated.

Die vorliegende Arbeit befasst sich mit dem Fluoreszenzverhalten, speziell der Fluoreszenzlebensdauer, von BODIPY-Farbstoffen in Polymerlösungsmittelgemischen mit unterschiedlicher Polymerkonzentration sowie in Polymerfilmen bei unterschiedlichen Temperaturen. Dazu werden zunächst die Synthesen von vier verschiedenen BODIPY-Fluorophoren mit einem Phenylsubstituent in meso-Position aufgezeigt. Dahingehend wurde eine Synthesestrategie entwickelt, um eine einzelne Polypropylenkette an diese Farbstoffsysteme anzubinden. Dabei soll aufgezeigt werden, dass die Länge des Substituenten am Phenylsubstituenten am chromophoren Kern maßgeblich das Fluoreszenzverhalten der Sonde beeinflusst. BODIPY-Farbstoffe mit makromolekularen Substituenten zeigen im Vergleich zu Derivaten mit kürzeren Substituenten eine deutlich größere Fluoreszenzlebensdauer und eine nicht so stark ausgeprägte Temperaturabhängigkeit. Mehrere Zeitkomponenten der Fluoreszenzlebensdauer der Fluorophore in reinem Polypropylen bzw. deren Mehrkomponentensystemen (Polyethylenpropylen Copolymer oder Kraton) im Vergleich zu reinen Lösungsmitteln (Toluol oder Dodecen) deuten dabei auf lokale Heterogenitäten im Material hin. Außerdem wird der Einfluss der Viskosität auf die Fluoreszenzlebensdauer in Polymer/Lösungsmittelgemischen mit unterschiedlicher Polymerkonzentration untersucht und die Rolle des Wasserstoffbrückennetzwerkes zwischen den Polymer- und Lösungsmittelmolekülen diskutiert.

Durch die Ergänzung von Organoblechen mit gewebten Strukturen aus Metalldrähten können hochbelastbare Bauteile gleichzeitig mit einer abschirmenden Wirkung versehen werden und ermöglichen so Anwendungen wie beispielsweise im Umfeld der Elektromobilität. Im Rahmen der vorliegenden Arbeit wird ein polypropylen-basierter Schichtverbund aus thermoplastischen Hochleistungsfaserverbunden und Metalldrahtgewebe hinsichtlich seiner Eignung zur Abschirmung elektromagnetischer Wellen für Gehäusestrukturen und seiner Verarbeitbarkeit im Spritzgießen näher analysiert. Die Untersuchungen zeigen den Einfluss von Defekten, wie sie bei der Herstellung realer Bauteile entstehen können, und deren Auswirkung auf die Abschirmwirkung des Bauteils. Darüber hinaus werden mit Vibrations-,Infrarot- und Heißgasschweißen mögliche Fügeverfahren aufgezeigt und hinsichtlich ihrer Abschirmwirkung bewertet, die auch eine elektrische Kontaktierung über die Fügestelle hinweg ermöglichen.:1 Einleitung 2 Grundlagen 3 Experimentelles 4 Analyseverfahren 5 Untersuchungsergebnisse 6 Zusammenfassende Bewertung der Ergebnisse 7 Zusammenfassung / By combining endless glass fiber reinforced thermoplastic semifinished products with embedded metal wire meshes it is possible to produce highly stressable parts, which additionally allow shielding of electromagnetic waves. Therefore these party can be used for electric cars. In this study a multi-layer film, consisting of polypropylene-based organosheets, PPGF30 and metal wire meshes, is analyzed regarding its suitability for shielding against electromagnetic waves and its processability in injection molding. The analysis show the influences defects, which accure during the production of housings, and their impact of the shielding effectiveness. Moreover possible joining technologies, such as infraredwelding, vibrationwelding and ultrasonicwelding, are studied and evaluated whether it’s possible to create a electrically conductive joint.:1 Einleitung 2 Grundlagen 3 Experimentelles 4 Analyseverfahren 5 Untersuchungsergebnisse 6 Zusammenfassende Bewertung der Ergebnisse 7 Zusammenfassung

In der vorliegenden Arbeit wird das bruchmechanische Verhalten von Materialien untersucht, welche mit einer Faserverstärkung ausgestattet sind. Dies geschieht unter Zuhilfenahme unterschiedlicher Ergebnisse und Methoden aus der stochastischen Geometrie. Ein zentrales Ergebnis dieser Arbeit ist die Entwicklung eines Modells einer stochastischen kohäsiven Zone, welche bruchmechanische Vorgänge nahe der Rissspitze faserverstärkter Materialien beschreibt. Hierbei können Eigenschaften der zufälligen Natur der Faserverstärkung wie z.B. die Verteilung der Faserlänge und -orientierung aber auch der Natur der zufälligen Lage der Fasern zueinander verwendet werden. Mit Hilfe dieser und weiterer Charakteristiken des faserverstärkten Materials kann sowie der mittlere mechanische Widerstand gegen Rissöffnung als auch die Varianz desselben berechnet werden. Damit bildet diese Arbeit eine wesentliche Erweiterung und Verallgemeinerung ähnlicher Ergebnisse aus der Vergangenheit, welche mit diesem Thema beschäftigten. Darin wird lediglich der mittlere mechanische Widerstand unter Annahme konstanter Faserlänge und isortroper Faserorientierung thematisiert. In der vorliegenden Arbeit wird gezeigt, dass für Materialien mit gestreuter Faserlänge diese Annahme zu erheblichen Modellierungsfehlern führen kann. Darüber hinaus wird ein numerisches Verfahren vorgeschlagen um die erarbeiteten mathematischen Gleichungen effizient auszuwerten. Mit Hilfe der damit verbundenen Berechnungen und praktischen Messungen an faserverstärkten Materialien konnten die Ergebnisse des stochastischen Modells validiert werden.:1. Einleitung 2. Grundlagen und Begriffe 3. Stochastische Darstellung von Fasersystemen 4. Modellierung des mittleren Spannungs-Separations-Verhaltens 5. Die Varianz des Separationswiderstands 6. Monte-Carlo-Simulation der Modus-I-Separation mit Fasern 7. Experimentelle Validierung und Anwendung des stocahstischen Modells 8. Zusammenfassung und Ausblick

Thermoplastic Vulcanizates (TPVs) are itself a commercially high valued group of polymer blend. They render technological properties of conventional vulcanized elastomers with the ease of thermoplastic melt (re)processability. With ever growing market, TPVs have got plenty of applications among various fields. Here, the technological properties of these TPVs were tailored according to the purpose by interplaying physical parameters of polymers and advanced high energy electron technology. Electron irradiation, though a well-known technique for cross-linking in polymer industry, is only restricted to final product treatment. We take it to the next level by coupling a conventional internal mixer and a high energy electron accelerator. Polypropylene (PP) and natural rubber (NR) based TPVs have been prepared using this new reactive processing technology, named Electron Induced Reactive Processing (EIReP). Various electron treatment parameters were explored to maximize technological properties of TPVs. Effects of various polyfunctional monomers (PFM) were also studied. In an endeavor to develop a potential method for customization, deep insights of macroscopic and microscopic structure of these TPVs were presented with the help of various advanced scientific characterization techniques. Commonly faced difficulties like viscosity mismatch, cure rate mismatch, and incompatibility due to different molecular structures were furnished along with plausible solutions. Investigation of phase inversion from co-continuous matrix to thermoplastic matrix was dealt with special care as it helps to understand structure property correlation for all TPVs. To make the whole effort relevant, at the end of this thesis a summary of various technological properties has been given for the newly processed and commercially available TPVs.

Polypropylene (PP) is a common thermoplastic and frequently adapted permanently with increasing requirements by adding fillers as well as reinforcing materials. Because of incompatibility of non-polar PP and polar inorganic filler, resulting composites are brittle which has a detrimental effect on the desired properties. Improvements in mechanical properties can be reached by compatibilization, creating of chemical couplings between phases and by increasing of inhomogeneity. Thus, maleic anhydride grafted PP is used as well as reactive processing of PP in presence of peroxide radical initiators. The temperature dependence of peroxide decay as well as the dependence of radical generation rate on time are two disadvantages of peroxide induced reactive processing. Modification of polymers with high energy electron treatment is also well known and used to form parts (after) molding as well as raw materials (pellets, powders, fibers) in solid state and at room temperature. The spatially and temporally precise input of energy is used to produce desired material properties on radical-induced chemical reactions. Coupling of high energy electron modification of polymers and melt mixing offers a new possibility of reactive processing. In this case, radical generation is independent of temperature, can be easily controlled by beam current and kept constant over time. Absence of any crystallinity, high reaction rates as well as intensive macromolecular mobility and intensive mixing are reasons to expect novel structures and properties. Electron beam induced reactive processing is a novel technique where chemical reactions are induced by spatial and temporal precise energy input via high energy electrons under dynamic conditions of melt mixing. This method gives the possibility to increase surface energy of polypropylene (PP) effectively as well as to generate chemical couplings between filler and PP. The process was applied to a proved system consisting of PP (38 wt%), magnesium hydroxide (MH) (60 wt%), triallyl cyanurate (TAC) (2 wt%). This composite system was successful tested in peroxide induced conventional reactive processing. Absorbed dose imparted per rotation of rotors is a new parameter controlling mechanical properties of polymer composites. Improved properties were found in tensile strength (150 %), elongation at break (175 %), and impact strength (175 %). It can be shown that chemical couplings are generated during electron induced reactive processing in comparison to only compatibilized material.

Isotactic polypropylene (iPP), as one of the most versatile commodity thermoplastic polymers, is a polymorphic material having several crystal modifications, among which the β-form exhibits higher performance including excellent impact strength and improved elongation at break.Up to now, the effective and convenient way to prepare the iPP with high content of β-phase has been successfully achieved by addition of certain β-nucleating agent. Since the coexistence of β-nucleating agent and flow (shear flow, extensional flow or mixed), which usually exists in common industrial processing, makes the crystallization process more complex, their combined effect on the structure evolution of polymers, especially in the early stage of crystallization is still not well understood. The mechanical properties of iPP depend strongly on its crystallinity, crystal orientation and morphology determined by the conditions during preparation. On the other hand, the mechanical properties of polymers can also be modulated by deformation processing, which is directly related to the deformation-induced structure transition. However, the transition mechanism of different crystal forms and structure-property correlation still remain unclear. In this thesis, time-resolved synchrotron X-ray scattering was firstly used for the in-situ study of the structural and morphological developments of β-nucleated iPP during shear-induced crystallization. It was found that the crystallization process was strongly influenced by the concentration of β-nucleating agent, shear rate and shear temperature. Then extension-induced crystallization was investigated by a novel melt draw experiment, where a different crystallization mechanism compared to the shear-induced crystallization was found. Subsequently, β-nucleated iPP samples with different thermomechanical histories were scanned by synchrotron X-ray microbeam to construct their overall morphological distributions, including distributions of crystallinity, lamellar thickness, orientation, etc. Finally, these morphology-identified samples were investigated by in-situ synchrotron X-ray measurements coupled with mechanical testing to follow the structure evolution during deformation at elevated temperature. It was found that the deformation behaviour of β-nucleated iPP was closely associated with its initial morphology, its subsequent variation during stretching as well as the stretching conditions including the stretching rate and stretching temperature. The current study would not only contribute to the development of crystallization and deformation theory but also be beneficial for the material design.

The diploma thesis focuses on the optimization of technological parameters of plastic injection molding and the study of the influence of technological parameters on the quality of molded test specimens’ type 1A. The quality of molded parts for 3 types of polypropylene (PP) with different melt flow rate (Mosten GB 002, Mosten GB 218, Mosten MA 230) and 1 type of polystyrene (PS) (Krasten PS GP 154) was evaluated in terms of dimensional stability and weight. The contribution of software for modeling the plastic injection molding process was evaluated in this work. SOLIDWORKS Plastics software was used to optimize technological parameters. The construction of the bodies, mold and cooling system was constructed, and test bodies were produced on the basis of parameters obtained from the simulation of the injection molding process. Their quality parameters were compared with a 3D model and for each of the studied materials the optimal technological parameters were selected in terms of quality and the degree of influence of individual injection parameters on the quality of moldings was evaluated. The accordance of the results of the theoretical simulation with the real experiment was proved and a computational module independent of the optimized quality parameters, generally suitable for optimizing the quality parameters of the injected parts, was developed.