This master‘s thesis concerns gel polymer electrolytes formed on a methyl methacrylate base with selected types of nanoparticles. In the thesis are also analyzed the methods for measuring electrochemical properties. The practical portion deals with sample preparations of gel polymer electrolytes with different contents of alkaline salt in a solvent, creating gels with different nanoparticle content and comparing gel polymer electrolytes polymerized with heat and UV radiation. The thesis deals with the evaluation of these samples from the viewpoint of electrical conductivity and potential windows as well as thermal analysis of selected samples.

The theoretical part of this thesis is focused on bulk radical polymerization of styrene, methylmethacrylate, vinyltoluene and paramethylstyrene. It summarizes actual informations about kinetics and performance possibilities of bulk polymerization. Experimental part deals with polystyrene prepolymers preparation by bulk polymerization. The aim is to find optimal conditions for prepolymers preparation. Prepolymers should be usable for subsequent polymerization nearly up to 100% conversion. Conversion values were gravimetrically determined and molecular weights were obtained by viskosity measurements, which were realized by Ubbelohde viscometer. In the experimental part, there were performed simulations targeted on conversion dependence on time. The purpose was a prediction of monomer conversion at a given time during polymerization. Differences between reality and simulation were low in most of cases and the found form of kinetic behavior calculations provides satisfying results. In the conclusion of this thesis was suggested a new procedure for polystyrene prepolymers preparation.

Ph. D. (Department of Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology. / Investment casting process is the most suitable technique for producing high quality castings which are dimensionally accurate with excellent surface finish and complex in nature. Recently with the ever-changing manufacturing landscape, the process has been increasingly used to produce components for the medical, aerospace and sports industry. The present study looked at three investigative scenarios in the development of a pattern material for investment casting process: (i) the development of wax/ethyl vinyl acetate (EVA) and wax/linear low-density polyethylene (LLDPE) blends as the carrier vehicle materials for the development of pattern material for investment casting; (ii) the development of wax/EVA/polymethyl methacrylate (PMMA) based investment casting pattern and lastly (iii) the development of wax/LLDPE/PMMA based investment casting pattern material. The first part of the studies elucidates the effects in terms of the thermal, mechanical, surface and rheological properties when paraffin wax in blended with poly EVA and LLDPE. The developments involved the extrusion of seven formulations for EVA and also LLDPE using a twin-screw extrusion compounder. The paraffin wax weight percent investigated ranged from 33% to 87% thus encompassing both low and high wax loading ratios. The thermal properties of the developed binary blends were characterized via thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The mechanical properties were characterized using three-point bending test. The thermo-mechanical and rheological properties were determined using thermomechanical analysis (TMA) and a rheometer respectively. A scanning electron microscope (SEM) was used to study the surface texture of the extruded blends. The thermal properties indicated that the thermal stability of paraffin wax is improved when it is blended with both EVA and LLDPE. DSC curves showed two endothermic melting peaks and two exothermic crystallisation peaks. In the case of wax/EVA blends, there was no distinct peak showing the independent melting of neat wax and EVA. The peak at a temperature of 50 – 72 °C corresponds to the melting of the wax/EVA blend. In the case of wax/LLDPE blends, the peak at 50 -66 °C corresponds to the melting of wax whereas the large peak at 112 - 125°C corresponds to the melting of the LLDPE. Wax/EVA and wax/LLDPE had improved mechanical properties as compared to that of neat wax. The rheological properties of both the EVA based and LLDPE based blends indicated that the viscosity of the blends increased as compared to that of neat wax. SEM confirmed that EVA alters the wax crystal habit at higher concentrations. In the case of wax/LLDPE blends, at 20-30 % wax content, a heterogeneous surface was observed, indicating the immiscibility of the paraffin wax within the LLDPE matrix. At a high wax content, there was agglomeration of wax. LLDPE allows amorphous structure of wax to disperse easily between the chains. The second part of the studies focussed on the wax/EVA filled with poly (methyl methacrylate) (PMMA) microbeads. TGA behaviour on the pyrolysis of wax/EVA/PMMA showed that the compounds volatilise readily with virtually no residue remaining above 500 °C. The DSC curves indicated that, the incorporation of PMMA reduced the crystallinity of wax/EVA blend. A distinct endothermic peak and another small peak was observed in all the formulations. The mechanical properties of wax/EVA/PMMA improved significantly. The methylene group present in both wax and EVA combined to form a blend with enhanced mechanical properties whereas the PMMA microbeads improved the needle penetration hardness. The melt viscosity of wax/EVA/PMMA increased as the EVA and/or the PMMA content is increased. The rheological experimental data fitted with the data predicted using the modified Krieger and Dougherty expression. The maximum attainable volume fraction of suspended PMMA particles was at max = 0.81. The SEM micrograph of wax/EVA/PMMA revealed a near perfect spherical nature for the filler particles in the wax/EVA polymer matrix. It further shows that the PMMA microbeads were weakly bonded and well distributed in the wax/EVA matrix. The third part of the studies focussed on the wax/LLDPE filled with Poly (methyl methacrylate) (PMMA) microbeads. The incorporation of LLDPE and PMMA into paraffin wax had a strong influence on the thermal properties, tensile properties, flow properties and its morphology. The TGA analysis showed that there was a slight observable decrease in the melting onset temperatures when the wax content was increased. From the DSC curves, the corresponding values of onset temperatures observed are between melting and crystallization temperature of neat paraffin wax and neat LLDPE. The short chains of the paraffin wax and the fragments formed by scission of wax chain have sufficient energy to escape from the matrix at lower temperatures. The slight decrease in peak temperatures associated with melting and crystallization could be attributed to the decrease in the average lamellar thickness of the blends. The tensile properties by three-point bending tests indicated an increase in the stress with an increase in the LLDPE content. This can be attributed to the formation of paraffin wax crystals in the amorphous phase of the blend which may influence the chain mobility. Since the paraffin wax used for this study had a low viscosity as compared to LLDPE, both LLDPE or PMMA had an influence on the viscosities of the blends. The data obtained from the experiments fitted with the data predicted obtained from the modified Krieger and Dougherty expression. The maximum attainable volume fraction of suspended PMMA particles was at max = 0.74. Similar observation with that of wax/EVA/PMMA was made in terms of the morphology of the wax/LLDPE/PMMA blends. The excellent thermal stabilities, the superior mechanical strength of wax/EVA/PMMA and wax/LLDPE/PMMA and the flow properties with relatively high EVA and also with high PMMA loadings, open new opportunities for EVA and LLDPE based pattern material for in investment casting process. It is worth pursuing further comprehensive studies since it offers a strong potential for realizing further technological improvement in the field of investment casting and rapid prototyping technologies.

The polymerization of methyl methacrylate (MMA) was investigated in this dissertation. Selected kinetic models from the literature were reviewed, and two new, generalized models of diffusion-limited effects (gel- and glass effects), derived from the current models were proposed and tested for bulk and solution polymerization of MMA in batch and semi-batch reactors, under isothermal and non-isothermal conditions. The newly proposed models include the capability of modeling termination by combination, radical transfer to monomer and depropagation reaction. The new and previous models were compared with experimental data of bulk and solution polymerizations of MMA, under a selection of non-steady state processes conditions (initiator and monomer feed, step changes in temperature) and compositions (initiator and chain transfer agents, regarding both type and dosages). The particular case of a non-isothermal bulk polymerization was also investigated. A simulation program (Reactormodel) was developed in Matlab, and its algorithm is provided. / Sem resumo.

Esta tese envolveu o estudo da dinâmica molecular em copolímeros em bloco compostos de poli(metacrilato de metila) (PMMA), poli(ácido acrílico) (PAA) e Poli(acrilato de chumbo) (PAPb) por técnicas de Ressonância Magnética Nuclear e de análise térmica (DSC e DMTA). Estes copolímeros em bloco foram sintetizados visando a obtenção de compostos para serem utilizados, tanto como lentes oftálmicas com maiores índices de refração, como materiais dedicados à proteção radiológica, sendo estas duas propriedades de emprego individual ou integrado. Para o estudo destes materiais, as amostras foram confeccionadas com várias composições, incluindo aquelas nas formas puras contendo apenas um bloco, resultantes da combinação de dois blocos, e as triblocos, com diferentes quantidades relativas de PAPb, variando de 1 a 40%. Para o caso do PMMA, a dinâmica molecular é bem conhecida, sendo caracterizada por uma relaxação β, que envolve mais especificamente movimentos de seus ramos laterais e que ocorre dentro de um amplo intervalo de temperatura centrado em torno da ambiente, e pela transição vítrea, que envolve, predominantemente, movimentos da cadeia principal que ocorrem para temperaturas em torno de 100oC. Devido à extensão destes dois eventos em grandes intervalos de temperatura, eles acabam se superpondo já em temperaturas abaixo de 100oC. O fato da relaxação β ocorrer para o PMMA em torno da temperatura ambiente, confere-lhe uma de suas características mais importantes, não ser quebradiço. Porém, devido à presença do grupo hidroxila no PAA, que permite a ocorrência de ligações de hidrogênio entre os diferentes ramos laterais, a relaxação β é suprimida neste material, tornando-o quebradiço e não adequado para as aplicações desejadas. No caso do copolímero tribloco, espera-se que o PAPb também possa interferir na característica mecânica final do material, em função de sua participação na dinâmica molecular do copolímero. Para este estudo foram preparadas várias amostras com diferentes quantidades relativas de PMMA, PAA e PAPb, de modo entendermos a dinâmica molecular destes materiais, individual e coletivamente, afim de selecionar os mais indicados para as aplicações tecnológicas almejadas. Para o estudo destas amostras, utilizamos tanto técnicas de análise térmica (DSC e DMTA), que fornecem, de forma relativamente rápida, dados importantes sobre a dinâmica macroscópica, quanto métodos básicos e avançados de RMN no estado sólido, que propiciam informações mais detalhadas sobre a dinâmica molecular. Estes estudos indicaram que a presença do PAA, obrigatória na rota de síntese utilizada para a inserção do PAPb, é um elemento indesejável no produto final, pois ele sempre atua na supressão da relaxação β. Adicionalmente, os dados obtidos indicaram que o PAPb, em grandes quantidades, também age na supressão desta relaxação. Embora a proposição destes novos materiais para a área oftálmica não ser muito adequada, já que a quantidade de PAPb necessária para a obtenção de amostras com bons índices de refração deve ser grande (bem acima de 5%, quando elas tornam-se quebradiças), as amostras com pequenos conteúdos de PAPb (até 5%) permitiram uma redução de até 50% dos raios-x incidentes. Finalmente, os estudos realizados por técnicas que observam detalhes da dinâmica molecular, tanto em níveis macroscópicos (DSC e DMTA), quanto moleculares (RMN), ofereceram excelentes informações básicas tanto sobre a mobilidade dos diferentes ramos que compõem os copolímeros em bloco, quanto a interação/miscibilidade entre os diferentes blocos, que afeta também a dinâmica global do sistema. / This thesis involved the study of molecular dynamics in triblock copolymers consisting of poly (methyl methacrylate) (PMMA), poly (acrylic acid) (PAA) and Poly (lead acrylate) (PAPb) by solid-state Nuclear Magnetic Resonance (NMR) and thermal analyses (DSC and DMTA). These block copolymers were synthesized in order to obtain materials not only presenting higher refractive index but also offering good radiological protection, which are useful for individual and combined applications. For the study of these materials, the samples were prepared with various compositions, including those in pure form containing only a block, resulting from the combination of two blocks, and the triblock with different relative amounts of PAPb, ranging from 1 to 40%. In the case of PMMA, the molecular dynamics is well known, characterized by a β relaxation, which involves more specifically the ester side-group dynamics occurring within a broad temperature range centered around the room temperature, and the glass transition, predominantly involving the main chain dynamics that occur for temperatures around 100oC. Due to large extension of these two dynamical events in wide temperature ranges, they merge at temperatures below 100oC. The fact that the β relaxation occurs for the PMMA around the room temperature, confers to it one of its most important features, toughness. However, due to the presence of the hydroxyl group in PAA, which allows the occurrence of hydrogen links between different branches, the β relaxation in this material is strongly suppressed, making it brittle and not suitable for the desired applications. In the case of the triblock copolymer, it is also expected that PAPb may also interfere with the mechanical properties of the final material due to its involvement in the full molecular dynamics of the copolymer. For this study, several samples were prepared with different relative amounts of PMMA, PAA and PAPb, in order to understand the molecular dynamics of these materials, individually and collectively, and select the most suitable ones for the desired technological applications. To characterize and study these samples, we employed thermal analyses (DSC and DMTA), which give quick and important data on the macroscopic dynamics, and basic and advanced solid-state NMR methods, which provide more detailed information about he molecular dynamics. These studies indicated that PAA, necessary along the synthesis route used for the insertion of PAPb in the triblock copolymers, is an undesirable element in the final product, because it is always acting on the suppression of β relaxation. Although the proposition of these new materials for the ophthalmic area is not very appropriate, since the amount of PAPb necessary to obtain good refraction indexes would be necessarily large (over 5%, when they become brittle), the samples with small amounts of PAPb (up to 5%, when they present good mechanical properties) allowed a significant reduction of about 50% of the incident x-rays. Finally, using solid-state NMR methods, including modern Exchange experiments and thermal analyses (DSC and DMTA), it was possible to understand in detail the individual and cooperative motions of the main chain and side groups. The most import result obtained indicate that, despite being important inserting PAPB and PAA in the block copolymer for improving the desired optical and x-ray shielding properties, the presence of these blocks tend to suppress the β relaxation, reducing thesample mechanical properties.

Gegenstand dieser Arbeit ist die Herstellung nicht hierarchischer und hierarchischer, poröser Polymermembranen mittels eines Templatverfahrens. Bei der Herstellung der hierarchischen Membranen wird eine Stützschicht mit mikrometergroßen Mulden und eine aktive Membranschicht mit submikrometergroßen Poren in einem Arbeitsschritt und aus einem Material erzeugt. Als Template für die Poren der nicht hierarchischen Membranen bzw. Mulden der hierarchischen Membran in der Stützschicht dienen Flüssigkeitstropfen. Diese werden auf Substraten mit Bereichen unterschiedlicher Benetzbarkeit erzeugt. Die Substrate werden anschließend mit einer Polymerlösung überschichtet, welche im Falle der hierarchischen Membranen sphärische, monodisperse Siliziumdioxidpartikel enthält. Die Siliziumdioxidpartikel ordnen sich bevorzugt in der Grenzfläche zwischen den Templattropfen und der Polymerlösung an. Nach Verdunsten des Lösungsmittels, Entfernen des Substrats und ggf. der Siliziumdioxidpartikel werden poröse Polymermembranen erhalten. Die nicht hierarchischen weisen Poren in der Größe der Templattropfen aus. Die hierarchischen Membranen zeigen dagegen eine Stützstruktur mit mikrometergroßen Mulden, entstanden durch die Templattropfen und eine Schicht auf der Oberseite der Membran mit submikrometergroßen Poren, die durch die Siliziumdioxidpartikel gebildet wurden. Außerdem wird gezeigt, wie das dargelegte Verfahren auf die Herstellung von Membranen aus dem Monomer VISIOMER HEMA-TMDI übertragen werden konnte

In der vorliegenden Arbeit wird die Synthese neuartiger, polynuklearer Bismutoxido-Cluster sowie deren Potential zur Verwendung als Bausteine zum Aufbau organisch-anorganischer Hybridmaterialien beschrieben. Die molekularen Verbindungen werden nach partieller Hydrolyse eines basischen Bismutnitrats in DMSO erhalten. Durch Zugabe von Additiven wie Carbon- und Sulfonsäuren können funktionalisierte Bismutoxido-Cluster erzeugt werden, die eine gute Löslichkeit in organischen polaren Lösungsmitteln besitzen. Die Charakterisierung der Produkte erfolgte mittels Einkristallröntgenstrukturanalyse, NMR- und IR-Spektroskopie sowie ESI-Massenspektrometrie. Erste Untersuchungen zur Synthese röntgenopaker organisch-anorganischer Hybridmaterialien auf der Basis von Bismutoxido-Clustern und Methylmethacrylat wurden durchgeführt. Hierzu wurde der nanoskalige Bismutoxido-Cluster [Bi38O45(OMc)24] als anorganischer Baustein gewählt. Die Oberfläche des Bismut-Sauerstoff-Gerüsts dieser Verbindung ist mit Methacrylat-Liganden bedeckt, welche eine gute Löslichkeit vermitteln und durch ihre polymerisierbaren Funktionalitäten eine kovalente Anbindung z. B. an Vinylmonomere ermöglichen. Die radikalische Copolymerisation von [Bi38O45(OMc)24] mit Methylmethacrylat liefert transparente Komposite, die anhand von Festkörper-NMR-Spektroskopie, IR-Spektroskopie sowie TG- und DSC-Analyse charakterisiert wurden.

Die vorliegende Arbeit befasst sich mit der Synthese von Alkylmethacrylat-Blockcopolymeren, der Charakterisierung ihrer chemischen Struktur und ihres Mikrophasenseparationsverhaltens sowohl im Festkörper als auch in dünnen Filmen. Grundlegendes Ziel war die Einführung funktioneller Gruppen in ein Alkylmethacrylat-Blockcopolymersystem. Eine erste Einschätzung der Effektivität von funktionalisierten Diblockcopolymeren als Template für die Darstellung geordneter Silica-Strukturen über Sol-Gel-Reaktionen von Alkoxysilanen wurde angestrebt. Es wurde das Diblockcopolymersystem Poly(pentylmetacrylat-b-methylmethacrylat) PPMA-b-PMMA untersucht. Dieses wurde nach dem Mechanismus der anionischen Polymerisation dargestellt, um eine größtmögliche Kontrolle über Molmassen, Zusammensetzungen und Polydispersitäten ausüben zu können. Als vielseitig modifizierbare und stabile funktionelle Gruppe wurde die Allylfunktion ausgewählt. Diese konnte durch Endcapping mit Allylbromid an das Kettenende der Diblockcopolymere angebunden werden. An den Kettenanfang konnte die Allylfunktion durch Initiierung mittels Allyllithium gebunden werden. Durch Kombination von funktionellem Initiator und funktionellem Endcapping wurden bifunktionelle Diblockcopolymere erzeugt. Multifunktionalisierte Blockcopolymerproben wurden ebenfalls durch anionische Polymerisation erhalten. Durch sequenzielle Polymerisation von PMA, Allylmethacrylat und schließlich MMA wurden Triblockcopolymere dargestellt. Zwei weitere Typen von multifunktionalisierten Diblockcopolymeren, in denen die funktionellen Gruppen nahezu statistisch verteilt über einen der beiden Blöcke vorliegen, wurden durch statistische Copolymerisation erhalten. Alle Klassen von mono-, di- und multiallylfunktionalisierten Blockcopolymeren konnten durch Hydroborierung mit 9-BBN und anschließende Oxidation in mono-, di- und multihydroxylfunktionalisierte Blockcopolymere überführt werden. Die polymeranaloge Umsetzung der Hydroxylfunktion in eine Triethoxysilylfunktionon konnte modellhaft an einem hydroxylfunktionalisierten PMMA durchgeführt werden. Das Mikrophasenseparationsverhalten der Blockcopolymere wurde durch eine Kombination von analytischen Methoden wie SAXS, T-SAXS, GISAXS, TEM und AFM untersucht. Der Einfluss von Anzahl und Position der funktionellen Gruppen auf die Phasenseparation wurde geprüft. Die dargestellten Blockcopolymere zeigen ein Mikrophasenseparationsverhalten, das weitgehend mit den bereits vorliegenden Ergebnissen übereinstimmt. Trotz des geringen Wechselwirkungsparamters von χPMA,MMA = 0,065 tritt Phasenseparation auf, der Übergang von nichtgeordneter zu geordneter Phase (ODT) kann an ausgewählten Proben verfolgt werden. Die Bulkmorphologien werden nicht durch die Anwesenheit von ein oder zwei funktionellen Gruppen der Allyl- oder Hydroxylfunktion beeinflusst. Sind deutlich mehr als zwei funktionelle Gruppen entlang der Blockcopolymerkette vorhanden, kann das Mikrophasenseparationsverhalten nicht mehr direkt mit dem der nichtfunktionalisierten Diblockcopolymere verglichen werden. Blockcopolymere mit funktionellen Gruppen, die statistisch verteilt über einen der Alkylmethacrylatblöcke vorliegen, verhalten sich prinzipiell wie Diblockcopolymere. Die Phasenseparation ist schlechter ausgeprägt als in reinen Diblockcopolymeren, teilweise kann keine Phasenseparation festgestellt werden. Zum Teil kann dies auf vergrößerte Polydispersitäten und nachträgliche partielle Vernetzungsreaktionen zurückgeführt werden. Durch den Einbau von deutlich mehr als zwei funktionellen Gruppen entlang der Kette wird eine Verstärkung der Tendenz zur Phasenseparation erreicht, wenn der effektive Wechselwirkungsparameter zwischen den Blöcken größer wird als im nichtfunktionalisierten Diblockcopolymeren. Sehr polare Gruppen wie Hydroxylfunktionen beeinflussen Mikrophasenseparationsverhalten und Morphologieausbildung der Alkylmethacrylat-Diblockcopolymere stärker als wenig polare Allylfunktionen. In Triblockcopolymeren mit einem multiallyl- bzw. multihydroxylfunktionalisierten Mittelblock strebt das System einem dreiphasigen Zustand entgegen. Die experimentellen Befunde zum Phasenseparationsverhalten wurden mit theoretischen Phasendiagrammen verglichen, die für nichtfunktionalisierte Diblockcopolymere und Triblockcopolymere mit einem multiallyl- oder multihydroxylfunktionalisierten Mittelblock durch Mean-Field-Kalkulation auf Basis der RPA simuliert wurden. Das experimentell ermittelte Phasenseparationsverhalten der dargestellten Proben erfolgt im Einklang mit der berechneten Spinodalbedingung. Zum besseren Verständnis des Phasenseparationsverhaltens wurde das dynamische Relaxationsverhalten des Systems betrachtet. Zu diesem Zweck wurden Untersuchungen mittels dielektrischer Breitbandspektroskopie durchgeführt. Es wurde gezeigt, dass lokale Beweglichkeiten in den untersuchten Blockcopolymeren gehemmt und kooperative Bewegungen der α-Relaxationsprozesse im PPMA-Block langsamer bzw. bei höheren Temperaturen und im glasartigen PMMA-Block schneller bzw. bei niedrigeren Temperaturen als in den jeweiligen Homopolymeren erfolgen. Nach Untersuchung der Festkörpermorphologie wurden nicht-, mono-, di- und multifunktionalisierte Blockcopolymere hinsichtlich ihrer Morphologieausbildung in dünnen Filmen untersucht. Prinzipiell finden sich in dünnen Filmen dieselben Morphologien wie in Bulk. Durch die eingeschränkte Geometrie der Filme kommt es in dicken Filmen zur Ausbildung von Strukturen, die parallel zur Siliciumwaferoberfläche ausgerichtet vorliegen, während in sehr dünnen Filmen mit Schichtdicken kleiner als die entsprechenden Bulkdomänenabstände stehende Strukturen erzwungen werden. Für zylindrische Morphologien ist der Einfluss der Filmdicke auf die Orientierung der Strukturen deutlicher als für symmetrische lamellare Morphologien. Im Hinblick auf eine spätere Anwendung von nanostrukturierten Diblockcopolymeren wurden im Rahmen des Projektes verschiedene Ansätze verfolgt, für die nicht-, mono- und difunktionalisierte Diblockcopolymerproben der vorliegenden Arbeit von Projektpartnern eingesetzt wurden. Besonders wichtig war in diesem Zusammenhang die Anwendung von Blockcopolymeren als Template zur Erzeugung geordneter Silica-Strukturen. An der Universität von Modena und Reggio Emilia wurde eine Dissertation zum Thema organisch-anorganischer Hybridmaterialien durch den Sol-Gel-Prozess angefertigt. Die in der genannten Arbeit entwickelten Methoden wurden für die vorliegende Arbeit übernommen und für multifunktionalisierte Blockcopolymersysteme weiterführend selbst untersucht. Erste Untersuchungen zur Einschätzung der Templateigenschaften von Alkylmethacrylat-Blockcopolymeren in Silica-Sol-Gel-Reaktionen wurden an einigen multihydroxylfunktionalisierten Di- und Triblockcopolymeren durchgeführt. Die ersten vorliegenden Ergebnisse geben Grund zur Annahme, dass multihydroxylfunktionalisierte Blockcopolymere in der Lage sind, die Ausbildung von Silica-Partikeln bei in-situ durchgeführten Sol-Gel-Reaktionen mit SiO2-Precursoren in eine Richtung zu lenken, eine chemische Anbindung von organischer und anorganischer Phase zu erzwingen und die Form der ausgebildeten Silica-Nanostrukturen durch die vorgegebene Diblockcopolymermorphologie zu beeinflussen. Tatsächlich ist es gelungen, Silica in geordneter Weise in die Zylindermorphologie von PPMA-b-PMMA-Diblockcopolymeren einzubinden. Versuche, die organische Matrix durch Lösungsmittel oder Pyrolyse zu entfernen und die verbleibenden Silica-Strukturen hinsichtlich Ihrer Form und Porosität zu charakterisieren, werden zukünftig zum Verständnis des Bildungsprozesses in einer bevorzugten Phase oder an deren Grenzfläche beitragen. Die Steuerung der Silica-Partikelform kann nur dann tatsächlich gezielt erfolgen, wenn Phasenverhalten und Morphologiebildung für das Composit-System mit Silica-Precursor und verschiedenen Zwischenstufen mit jeweils unterschiedlichen Wechselwirkungen zu den Blockcopolymerphasen sowohl aus theoretischer Sicht verstanden als auch experimentell über eine größere Bandbreite nachgewiesen wurden. Das in dieser Arbeit entwickelte Blockcopolymersystem ließe sich in Bezug auf seine chemische Struktur sehr leicht auf vielfältige Weise erweitern. Für multifunktionalisierte Blockcopolymere bietet sich eine große Bandbreite von Variationen hinsichtlich Zusammensetzung, Molmasse und Verteilung von funktionellen Gruppen über beliebige Positionen entlang der Polymerkette sowohl innerhalb der drei für die vorliegende Arbeit gewählten Klassen von Di- und Triblockstrukturen als auch außerhalb dieser an. Es wurde gezeigt, dass eingebaute Allylfunktionen in der Lage sind, Vernetzungsreaktionen einzugehen, die u. U. steuerbar sind und zu definierten Nanogelstrukturen umgesetzt werden könnten. Kohlenstoffdoppelbindungen bieten Angriffspunkte für eine Vielzahl von polymeranalogen Umsetzungen, so dass aus allylfunktionalisierten Blockcopolymeren ein Pool von unterschiedlich funktionalisierten Blockcopolymeren darstellbar ist. Die Resultate der vorliegenden Arbeit zeigen, dass eine Anbindung funktioneller Gruppen an das Alkylmethacrylat-Blockcopolymer unter den gewählten Bedingungen mit guter Kontrolle über Anzahl und Position der Gruppen entlang der Kette grundsätzlich möglich ist. Der Einfluss der erzeugten funktionellen Gruppen auf das Mikrophasenseparationsverhalten des Blockcopolymersystems wurde eingeschätzt und wird in künftigen Arbeiten zum Verständnis der Strukturbildung in organisch/anorganischen Hybridmaterialien beitragen. / The present study deals with the synthesis of alkyl methacrylate block copolymers, the characterization of their chemical structure and the microphase separation behavior in bulk and thin films. The main objective of this work was the attachment of functional groups to an alkyl methacrylate diblock copolymer system. A first evaluation of the ability of functionalized block copolymer structures to act as a templating material regarding silica formation in sol-gel synthesis of alkoxysilanes was aspired. The diblock copolymer system of poly(pentyl metacrylate-b-methyl methacrylate) (PPMA-b-PMMA) was chosen. It was synthesized following the mechanism of anionic polymerization to achieve effective control over molar mass, composition and polydispersity. The allyl functionality was chosen for a versatilely modifiable and stable functional group and attached to the terminal chain end by endcapping the living polymer chain ends with allyl bromide. The head of the chain was functionalized by initiation with allyl lithium. By combining functional initiation and endcapping, bifunctional diblock copolymers were synthesized. Furthermore multifunctionalized block copolymers were produced by anionic polymerization. By sequential anionic polymerization of PMA, allyl methacrylate and finally MMA, triblock copolymers were obtained. Two more classes of multifunctionalized block copolymers with functional groups randomly distributed in one of the two blocks were synthesized by random copolymerization. All types of mono-, di- and multiallylfunctionalized block copolymers were transformed into mono-, di- and multihydroxylfunctionalized block copolymers by hydroboration and subsequent oxidation. The polymer-analogue reaction of hydroxyl groups to triethoxysilane functions was carried out exemplarily for hydroxy terminated PMMA. The microphase separation behavior of the block copolymers was investigated by a combination of methods such as SAXS, T-SAXS, GISAXS, TEM and AFM. The influence of number and position of functional groups along the chain was examined. The block copolymers synthesized show a microphase separation behavior in accordance to previous results. Despite the low value of the Flory-Huggins interaction parameter χPMA,MMA = 0,065 phase separation occurred and the transition from the ordered to the disordered state (ODT) was followed for selected samples. Bulk morphologies are not influenced by the presence of one or two allyl or hydroxyl groups. In case of considerably more than two functional groups attached to the block copolymer chain the microphase separation behavior of nonfunctionalized and functionalized block copolymers cannot be compared directly. Block copolymers having functional groups randomly distributed along the chain of one of the two methacrylic blocks generally show the typical behavior of diblock copolymers. Their phase separation becomes less pronounced than in pure diblock copolymers, sometimes cannot be detected. To some extent this observation may be referred to increased polydispersities and partial crosslinking. If considerably more than two groups were attached to the block copolymer chain, the tendency towards phase separation increased in case of an increasing value of the effective interaction parameter compared to nonfunctionalized diblock copolymers. Microphase separation behavior and morphology formation are more affected by highly polar groups such as the hydroxyl function than by less polar groups like the allyl function. In triblock copolymers with a middle block of successive allyl or hydroxyl functions the systems tends to form a three phase system which offers much more possibilities regarding the formation of ordered structures. Experimental results of phase separation were compared to theoretical phase diagrams, which were calculated by a Mean Field approach for nonfunctionalized diblock and triblock copolymers with multiallyl- or multihydroxylfunctionalized middle block based on RPA. The experimental results are in good accordance with the simulated spinodal condition. To increase the understanding of microphase separation processes, the dynamic relaxation behavior of the system was investigated. Therefore samples were examined by broadband dielectric spectroscopy. It was shown that local movements of the block copolymer system were decelerated in general, cooperative dynamics of the α processes were slowed down for the fluent PPMA block while they were accelerated for the glassy PMMA block. After bulk morphology investigation thin films of non-, mono-, di- and multifunctionalized block copolymers were prepared. Generally thin films develope the same morphologies as in the bulk state. Due to the confined geometry of a thin film thick films tend to form structures oriented parallel to the wafer surface, while in thin films with thicknesses lower than the respective bulk domain spacing standing structures are constraint. For cylindrical morphologies the impact of film thickness is more obvious than in symmetric lamellar structures. With respect to a possible application of nanostructured diblock copolymers different approaches were taken by project partners using non-, mono- and difunctionalized block copolymers of the present study. Remarkable in this context was the application of block copolymers as template for the creation of ordered silica structures. A doctoral dissertation on organic/inorganic hybrid materials by sol-gel process was prepared in Modena. Methods developed in this thesis were adopted to the present study and further investigated on multifunctionalized block copolymer systems. First investigations aiming at the evaluation of the templating abilities of alkyl methacrylate block copolymers in silica sol-gel reactions were carried out with multihydroxyfunctionalized di- and triblock copolymers. Preliminary results give reason to the expectation of multihydroxyfunctionalized di- and triblock copolymers being able to direct the formation of silica nanoparticles in sol-gel reactions carried out in situ with silica precursors, enforcing the chemical bonding between organic and inorganic phases and influencing the shape of silica nanostructures by the default block copolymer nanostructure. Indeed silica was incorporated successfully into the cylindrical structure of PPMA-b-PMMA diblock copolymers. Future experiments on removing the organic matrix by solvent or pyrolysis to investigate shape and porosity of the remaining silica structures will increase the understanding of the silica formation process inside a preferential phase or at the interface of the block copolymers. Nevertheless, the silica particle shape can be taylored deliberately only if phase separation behavior and morphology evolution in the composite system containing silica precursor and several derivatives thereof with nonuniform interactions towards block copolymer phases are well understood from the theoretical point of view as well as experimental proof needs to be given over a broader range. The block copolymer system developed in the present study easily can be extended manifoldly regarding the chemical structure of the polymer. In the case of multifunctionalized block copolymers a tremendous variety of different products can be obtained by modulation of composition, molar mass and especially distribution of functional groups to any position along the polymer chain far beyond the limits of the three classes of multifunctionalized di- and triblockstructures chosen for this thesis. It was shown that allyl functions incorporated inherently are able to undergo crosslinking reactions, which may be controlled similarly to network formations by inorganic crosslinkers and may result in defined nanogel structures. Furthermore carbon doublebonds are open to attacks for various polymer-analogue reactions hence offering the possibility of creating a pool of differently functionalized block copolymers from a single sample of allylfunctionalized block copolymer. The results of the present study basically prove a feasibility of the binding of functional groups to alkyl methacrylate block copolymer chains with high control over number and position of functional groups along the polymeric chain. The impact of functional groups on the microphase separation behavior of the block copolymer system was evaluated and will increase the understanding of structure formation in organic/inorganic hybrid materials of future work.

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