Le travail de thèse a pour objectif la conception de micro-supercondensateurs tout-solide à base d’or nanoporeux, intégrés sur substrat de silicium. Dans un premier temps nous avons développé un procédé de formation de films d’or par réduction chimique auto-catalytique. Afin d’augmenter l’adhérence du film d’or sur le substrat de silicium, une couche d’accroche originale a été élaborée par procédé sol-gel. Il s’agit d’un film mince d’oxyde de zirconium (ZrO2) dopé par des nanoparticules d’or. La porosité de ces films d’or a été contrôlée par une méthode de templating à partir de microsphères de polystyrène (Ø ≈ 20 nm). Les films d’or nanoporeux peuvent atteindre 1,2 µm d’épaisseur en l’absence de délamination. La porosité est totalement interconnectée et la taille des pores (20 nm) a été choisie afin d’être compatible avec l’électrolyte utilisé. Le procédé fait uniquement intervenir des méthodes chimiques en solution et est totalement compatible avec les procédés classiques de micro-fabrication. Les films d’or nanoporeux constituant le matériau d’électrodes du micro-supercondensateur, ont été structurés par photolithographie sous la forme de peignes interdigités. L’imprégnation d’un électrolyte polymère gélifié (PVA / KOH) a permis de finaliser la fabrication du micro-supercondensateur tout-solide. Les caractérisations électrochimiques montrent que le micro-dispositif atteint une capacité surfacique de 240 µF/cm² à 20 mV/s, et peut endurer plus de 8000 cycles en ne perdant que 5% de sa capacité initiale. Ces performances sont comparables à celles des micro-supercondensateurs intégrés tout-solide reportées dans la littérature. / The thesis work aims at the design of nanoporous gold-based all-solid state micro-supercapacitors, integrated on a silicon substrate. In a first step, we have developed a process for the formation of gold films by auto-catalytic chemical reduction. In order to enhance the adhesion of the gold film to the silicon substrate, an original seed layer was produced by a sol-gel process. It consists in a thin film of zirconium oxide (ZrO2) doped with gold nanoparticles. The porosity of these gold films was controlled by a templating method using polystyrene microspheres (Ø ≈ 20 nm). Nanoporous gold films can reach a 1.2 μm thickness in the absence of delamination. The porosity is completely interconnected and the pore size (20 nm) was chosen in order to be compatible with the used electrolyte. The method only involves wet chemistry processes and is fully compatible with conventional micro-manufacturing processes. The nanoporous gold films constituting the electrode material of the micro-supercapacitor have been structured by photolithography in the form of interdigitated combs. The impregnation of a gelled polymer electrolyte (PVA / KOH) made it possible to finalize the manufacture of the all-solid state micro-supercapacitor. Electrochemical characterizations show that the micro-device reaches a surface capacitance of 240 μF/cm² at 20 mV/s, and can endure more than 8000 cycles, while losing only 5% of its initial capacitance. These performances are comparable to those of the all-solid state integrated micro-supercapacitors reported in the literature.

Effective tissue engineering scaffolds should mimic the physical and chemical attributes of native tissue. Native tissues have intricate patterns, a multitude of porosities, and large water contents that are each directly associated with their ability to regulate and support life function. Therefore, the physical architecture of scaffolds intended to mimic these tissues for engineering applications plays an important role in scaffold performance both in vitro and in vivo. Self-assembling molecules organize into intricate patterns with a complexity that resembles that of native tissue. Hyaluronic acid (HA) hydrogels are widely used in tissue engineering for a variety of applications but fail to offer physical architecture beyond the inherent hydrogel porosity. To address this issue, a novel method to impose architecture within thin HA-based films using crystal nucleation was developed in the Schmidt lab [1]. The work described herein extends this method for use in three-dimensional matrices, with the main vii goal being the creation of hydrogels with a complex macroarchitecture. Four in situ self-assembling molecules were used: glycine, guanidine, urea and potassium dihydrogen phosphate. The crystallization of each molecule creates a specific porous network within the hydrogel that is the negative imprint of the crystalline geometry. The novel restriction of aqueous polymer into the molecule interstitial crystalline space allows hydrogels to embody complex geometric lumen architectures. The hydrogels were characterized in terms of their internal architectures, swelling, bulk moduli, biodegradability, cytotoxicity and in vitro cellular response. The unique structure-property relationships displayed by hydrogels templated by each of the crystallizing molecules were characterized in regards to mechanical properties. The need for complex microscopic architecture is conserved over many tissue engineering applications and templated scaffolds were evaluated for two unique applications. Crystal-templated hydrogels were investigated for use as an artificial stem cell niche environment to expand undifferentiated neural progenitor cells. Additionally, the templated hydrogels were evaluated for the in vitro study of myelin expression from Schwann cells. A hydrogel that combines the biocompatible properties of HA and the architectural complexity of native tissue may prove beneficial for biomedical applications. / text

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Une série de précurseurs contenant des sous-structures organo-ioniques à base d'entités imidazolium, guanidinium, ammonium et zwitterionique ainsi que des précurseurs neutres contenant des sous-structures amido-thiol, amine-thiol et amine a été synthétisée. Ces précurseurs ont été utilisés pour la synthèse de matériaux silices hybrides nanostructurés par voie template. La formation de matériaux nanostructurés a été réalisée par des réactions d'hydrolyse-polycondensation par l'utilisation de différents agents de structuration. Ce travail avait pour but la détermination des principaux facteurs influençant la structuration des matériaux. Ainsi, nous avons préparé une série d'ionosilicates nanostructurés par une nouvelle méthode de structuration qui met en jeu des interactions spécifiques entre des paires d'ions ‘précurseur cationique - surfactant anionique' et ‘précurseur anionique - surfactant cationique'. Cette approche a permis d'accéder aux matériaux originaux de type PMO ionique. Finalement, nous avons utilisé pour la première fois des surfactants de guanidinium comme ‘template' dans la synthèse des silices ioniques nanostructurées de morphologie sphérique. Les matériaux nanostructurés contenant des sous-structures amine, amine-thiol, ammonium et zwitterionique développés au cours de ce travail présentent des surfaces spécifiques élevées et une bonne accessibilité des sites organiques. Ces propriétés font de ces matériaux des systèmes de choix pour des applications en catalyse ou en séparation. / A series of precursors containing organo-ionic substructures such as imidazolium, guanidinium, ammonium and zwitterionic entities and several neutral precursors containing thiol-amide, thiol-amine and amino groups were successfully synthesized. These precursors were used for the synthesis of nanostructured silica hybrid materials containing ionic substructures via soft templating approaches. The formation of structured materials was achieved using template directed hydrolysis polycondensation procedures in the presence of various structure directing agents. The goal of this study was the determination of the parameters influencing the structuring of the materials. Thus, we prepared a series of nanostructured ionosilicates using a new method of structuring that is based on specific interactions between ‘cationic precursor - anionic surfactant' and ‘anionic precursor - cationic surfactant' ion pairs. This new strategy allowed the synthesis of ionic 'periodic mesoporous organosilicas'. At the end of this thesis, we used a new ‘guanidinium' type template in the preparation of nanostructured i-silica hybrid materials with a spherical morphology. Nanostructured ionosilicates bearing amine, amino-thiol, ammonium and zwitterionic substructures prepared in this work present high specific surface areas and a high accessibility of the organic functional sites. Due to these features, these materials have large potential in the fields of catalysis and separation.

Le carbure de silicium (SiC) est un matériau léger possédant de nombreuses propriétés avantageuses : forte résistance mécanique, bonne conductivité et faible expansion thermiques, ainsi que chimiquement inerte sur une large gamme de températures. Ces caractéristiques font de lui un matériau de choix pour de nombreuses applications dans des conditions extrêmes, allant de la catalyse au gainage de combustible nucléaire de génération IV. Pour satisfaire aux spécificités de ces applications, le SiC se doit de posséder une surface spécifique élevée, et une porosité contrôlée.Nous avons étudié la faisabilité de la synthèse de SiC mésoporeux par une voie dite de « soft templating » utilisant des semifluoroalcanes (SFA) linéaires pour structurer un précurseur moléculaire du SiC, le 1,3,5-trisilacyclohexane (TSCH). En effet, la polymérisation du TSCH en polycarbosilane autour d’assemblages de SFA permet de structurer la matrice, puis de créer de la porosité lors du retrait du template. Le polycarbosilane est ensuite converti en SiC par un processus de calcination au cours duquel la porosité doit être conservée.Dans un premier temps, nous avons temps étudié les capacités d’auto assemblage des SFA dans le cyclohexane comme solvant modèle, puis dans le TSCH, par des techniques de diffusion des rayons X et des simulations des diagrammes de diffusion. Nous en avons appréhendé le comportement et déterminé les paramètres contrôlant la taille des objets. Nous avons ensuite réalisé la synthèse de SiC à partir du TSCH en présence de SFA.Les matériaux obtenus ne présentant pas les caractéristiques de surface spécifique et de porosité visées, nous avons élargi nos recherches à d’autres templates, dont un copolymère tribloc styrène-butadiène-styrène, qui a permis d’obtenir des SiC mésoporeux, amorphes ou cristallins, par une voie impliquant le greffage des précurseurs de SiC sur le copolymère. / Silicon carbide (SiC) is a light material with numerous interesting properties: strong mechanical resistance, weak thermal expansion, good heat conductivity and chemically inert on a large range of temperatures. These characteristics make SiC an appropriate material for various applications in extreme conditions, from catalyst to generation IV nuclear fuel cladding material. Nevertheless, to fulfill these application specificities, SiC has to show high specific surface area, and a controlled porosity.We have studied the possibility to synthetize mesoporous SiC by a soft templating approach using semifluorinated alkanes (SFA) to structure a SiC molecular precursor, the 1,3,5-trisilacyclohexane (TSCH). The TSCH polymerization into polycarbosilane around SFA aggregates can structure the matrix, that will create porosity after the template removal. Then polycarbosilane is converted into a SiC by a calcination process conserving the porosity.In a first time, we studied the self-aggregation capacities of SFA in cyclohexane as model solvent, and then in TSCH, by X-ray scattering techniques and simulations of scattering patterns. We discussed the behavior of SFA and determined the parameters controlling the size of the aggregates. Then, we proceeded to SiC synthesis from TSCH in presence of SFA.As resulting materials didn’t show the expected specific surface area and porosity characteristics, we enlarged our studies to other templates such as a triblock copolymer styrene-butadiene-styrene, which finally allowed us to obtain mesoporous SiC, amorphous or crystalline, by an approach involving the grafting of the SiC precursor onto the copolymer.

La mise en forme par ice-templating est un procédé d’élaboration permettant via la congélation d’une suspension, d’obtenir des matériaux poreux à porosité contrôlée. L’analyse des mécanismes régissant la congélation de suspensions concentrées en particules et leurs conséquences sur les microstructures poreuses, est très peu développée dans la littérature du point de vue de l’influence de la composition de la suspension, en termes de nature et quantité d’additifs. Les objectifs de ces travaux de thèse sont d’observer et caractériser in situ et ex situ la formation des structures par ice-templating. Il s’agit également d’établir les liens entre la composition des suspensions, le procédé et la morphologie poreuse obtenue pour les structures congelées et frittées qui en découlent. L’évolution de l’avancée du front de congélation d’un panel de suspensions d’alumine aux propriétés caractérisées a été observée par radiographie X et la microstructure des échantillons congelés et frittés a été caractérisée par tomographie X ou par MEB. Nous avons ainsi pu caractériser les différentes étapes de la congélation par ice templating, les microstructures congelées associées, l’influence de la composition de la suspension ainsi que les mécanismes générateurs de défauts. La force ionique générée par la quantité de dispersant, la présence ou non de liant et la vitesse de refroidissement des suspensions sont trois paramètres ayant des conséquences critiques sur la microstructure et sur l’orientation ou la désorientation des cristaux. Nos résultats apportent un éclairage inédit sur les mécanismes de congélation des sols étudiés en géophysique et notamment la formation de glace lenticulaire. / Ice-templating is a processing route used to obtain porous material with a controlled porosity by freezing a suspension. Researches focused on this subject so far revealed a lack of information about mechanisms controlling the freezing of suspensions with a high solid loading and their consequences over porous microstructures, depending on the composition of the suspension in terms of additives nature and quantity. The objectives of this work are to observe and characterize in and ex situ the formation of structures by ice-templating and to establish the relationships between the composition of suspensions, process and porous morphology of frozen and sintered bodies. The advancement of the freezing front of a panel of alumina suspensions, with characterized properties was investigated by X-ray radiography and the microstructures of frozen or sintered samples were characterized by X-ray tomography and SEM. We have defined the different stages of the freezing by ice-templating, the associated frozen and sintered microstructures, the influence of the composition of the suspension and the mechanisms responsible for defects creation. The ionic strength generated by the dispersant quantity, the addition or not of a binder and the cooling rate of suspension are three parameters with critical consequences on microstructures, orientation and disorientation of ice crystals. Our results shed a new light on the freezing mechanisms of soils in geophysics and more particularly the ice lenses formation.

Cette thèse, par une étude combinant modélisation et expériences, s'attache à comprendre l'interdépendance entre porosité, transport et adsorption dans les matériaux poreux hiérarchiques. Le transport et l'adsorption sont simulés dans les matériaux poreux à l'aide d'un modèle de Lattice Boltzmann étendu pour prendre en compte l'adsorption. Ce modèle mésoscopique permet de simuler le comportement d’un fluide présent au sein des pores du matériau ainsi que d'espèces en solution. La synthèse des matériaux poreux hiérarchiques par ice-templating et la caractérisation de la géométrie des échantillons par tomographie aux rayons X a permis de réaliser des simulations sur des géométries réelles. La comparaison des résultats de simulation et des résultats expérimentaux a prouvé la capacité du modèle à reproduire le comportement du fluide et des espèces dans le matériau. Grâce au modèle employé, l'interdépendance entre transport et adsorption a pu être mise en évidence, montrant notamment que le flux de fluide pouvait avoir une influence sur la densité adsorbée. Une étude sur l'influence de la géométrie et de la rugosité sur le couplage entre transport et adsorption a été menée sur des géométries bien caractérisées. Enfin, la modification du modèle de Lattice-Boltzmann pour rendre compte de l'effet d'un pic de traceurs a été développé. Cette modification permet notamment d'observer la cinétique hors régime stationnaire des traceurs dans le matériau et de rendre compte de l'effet du flux sur l'accessibilité des sites d'adsorption. / The aim of this work concerns the interplay between porosity, transport and adsorption in hierarchical porous materials. This work combine a simulation and an experimental approach. Transport and adsorption are simulated with a Lattice-Boltzmann model recently extended to take adsorption into account. This mesoscopic model allows to compute fluid and solute behavior in porous materials. The synthesis of hierarchical porous materials using ice-templating and the characterization of materials geometry with X-ray tomography allowed to compute simulations on real materials. The comparison between experimental and simualtion results have proved the efficency of the model to model fluid and species behavior in the materials. Using this model, the interplay between transport and adsorption have been studied highlighting an effect of the fluid flow on adsorbed density. The effect of roughness and material geometry have also been studied. Finally the modification of the modelallows now to simulate the kinematic of a pulse of species. This modification gives a tool to perform simulation in non-steady state flow and evaluate the adsorption site accessibility regarding to the flow field.

Through progressive industrialization and the relentless consumption of natural raw materials, man is exerting a negative influence on his habitat. In particular, water as the basis of life and almost all processes of our economy is contaminated by various pollutants due to excessive use and insufficient purification. Here, oxyanions, heavy metal ions and organic pollutants pose a high risk to aquatic habitats and ultimately to humans. Due to insufficient removal, they also contribute to the loss of non-renewable raw materials for industrial cycles. Due to a mostly low effect concentration and potential interactions with diverse living organisms, the removal of many contaminants is extremely important to avoid further altering existing ecosystems. Adsorption represents an energy-efficient method of removal using adsorbents suitable for this purpose. Highly cross-linked resin polymers such as poly(melamine-co-formaldehyde) (PMF) with its excellent chemical resistance, high number of functional groups and ease of preparation, represent promising starting points for adsorbents. This dissertation describes the colloidal aqueous synthesis of nanoporous resin particles (e.g. PMF) by templating with SiO2 nanoparticles (SiO2 NPs), which are subsequently used to adsorb water pollutants. An overall goal of this work consists of elucidating the mechanism for particle and pore formation by systematically varying various synthesis parameters. Electron microscopy, N2-soprtion and particle size measurement are used to analyze the morphology, size and pore structure of the particles. Comprehensive investigations thus allow to determine the influence of each tested synthesis parameter on these properties. A very important goal, especially for future large-scale applicability, is the colloidal production of uniform particles, which have both a high ordered porosity and particle diameters in the range of a few micrometers. This enables an application as a fixed-bed adsorber that can be flowed through. This goal is closely linked to the mechanistic elucidation of pore and particle formation in the synthesis. The prepared nanoporous PMF particles were tested for various adsorption applications after their characterization. In order to obtain a comprehensive picture of the applicability of PMF particles, experiments with oxyanions, with pharmaceuticals as representatives of organic pollutants and with heavy metal ions will be carried out respectively. On the one hand, these experiments will focus on investigating the adsorption performance and mechanism of PMF with the respective pollutant. On the other hand, the influence of the changed porosity on the adsorption mechanism is investigated by using different particles of a varied synthesis parameter. Sulfate and phosphate ions were investigated in the oxyanion class. Extremely high separation rates were demonstrated for both ions, significantly outperforming previous commercially available materials. In experiments concerning a potential selective adsorption and thus separation of both species, the PMF/SiO2 hybrid particles, in which the template had not yet been removed, showed a selective sulfate adsorption. The immobilization of heavy metal ions was analyzed with special focus on the simultaneous separation of the Cu2+ ions and respective anions used here. Investigations of the adsorbent after the adsorption experiments by means of electron microscopy, X-ray scattering and electron spin resonance spectroscopy elucidated the adsorption mechanism, which had been insufficiently analyzed so far. Here, adsorption and surface-induced precipitation were identified as partially separate subprocesses, both of which are responsible for the separation of both metal and anions from solution. In adsorption experiments with the monovalent ions nitrate and chloride, a two-step uptake process was identified, which was mathematically described for the first time via a new adsorption isotherm. In the scope of organic water pollutants, the separation of the pharmaceutical diclofenac is being tested. In particular, the adsorption of pharmaceuticals is an urgent issue due to their low effect concentration and ubiquity in surface and tap waters. Pharmaceutical separation using PMF has hardly been investigated worldwide despite its promising properties. In these experiments, particles templated with SiO2 NPs of different sizes and stabilized in different ways were tested. This resulted in pore systems that varied from each other especially in their accessibility of the pore system and in the diameter of the connecting channels between the main cavities. These characteristics significantly affected the adsorption capacity and separation rates in low concentration range. A final goal is to synthesize a resin network that uses an equally highly functional triazine-based monomer instead of melamine. The monomer 2,4,6-tris(2,4,6-trihydroxyphenyl)-1,3,5-triazine (3PT) possesses nine hydroxyl groups each, whereby a polymer based on it should exhibit strongly modified adsorption properties compared to PMF. This monomer was used in an aqueous polymerization analogous to PMF to produce a previously unknown polymer network, which was designated P(3PT-F). Here, templating was omitted because the newly prepared material already exhibited intrinsic nanoporosity due to the size of the 3PT monomer. In subsequent adsorption experiments, very high separation rates were demonstrated for the toxic metal ions Pb2+, Cd2+ and Ni2+. In realistic initial concentrations, the contamination was reduced to drinking water quality in each case. P(3PT-F) also showed highly selective removal of Pb2+ over the common ions Ca2+, Mg2+, K+ and Fe2+. As fundamental evidence, reusability was also demonstrated by complete desorption with dilute HCl and subsequent re-adsorption without significant reduction in capacity. Overall, starting from the fundamental study of PMF particle synthesis, a more general understanding of aqueous dispersion polymerization of hydrophobic resins was first derived and templating with hydrophilic SiO2 NPs was implemented. With the help of understanding the particle growth processes and interactions responsible for templating, the properties of the resulting particles could be controlled. Subsequently, the influence of the changed porosity in particular on the separation performance could be investigated in the adsorption studies. In addition, it was possible to analyze which interactions PMF enters into with the respective pollutant types. By replacing the monomer melamine with a hydroxyl-containing monomer, a novel resin polymer could be produced. With its altered porosity and reactivity, this can now serve as a new starting point for adsorption experiments with strongly altered adsorption performance, e.g. towards heavy metal ions.:Abstract 1 Kurzfassung 5 List of Publications 9 First-Author Publications 9 Co-Author Publications 10 Patent 12 Conference Proceedings 12 Oral Presentations 12 Poster 12 List of Figures 13 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal: 14 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal: 15 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles: 16 SiO2 Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles: 18 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions: 19 List of Tables 21 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal: 21 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal: 21 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles: 22 SiO2 Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles: 22 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions: 23 Abbreviations 25 Symbols 26 1. Introduction 1 2. Objectives and Experimental Design 5 3. Scientific Background 11 3.1. Poly(melamine-co-formaldehyde) 11 3.1.1. Polymerization Mechanism 11 3.1.2. Synthesis Strategies for the Preparation of Porous PMF Particles. 13 3.1.3. Fields of Application of PMF 13 3.2. Adsorption 15 3.2.1. Adsorption Isotherms and Mathematical Modeling 16 3.3. Surface Precipitation 20 4. Fundamentals of Instrumental Analytics 23 4.1. Gas Sorption Measurements 23 4.1.1. Determination of Pore Sizes 26 4.1.2. Determination of Specific Surface Area 27 4.2. Transmission Electron Microscopy 29 4.3. Inductively Coupled Plasma Optical Emission Spectroscopy 31 Results and Discussion 33 Chapter Overview 33 5. Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal 37 Graphical Abstract 37 Abstract 37 1. Introduction 38 2. Results and Discussion 39 2.1. Synthesis and Characterization of the PMF Particles 40 2.2. Sorption Experiments 47 3. Materials and Methods 54 3.1. Materials 54 3.2. Methods 54 3.3. Synthesis of the PMF Particles 56 3.4. Water Treatment Experiments 57 4. Conclusions 59 6. Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal 65 Graphical Abstract 65 Abstract 65 1. Introduction 66 2. Materials 68 3. Methods 68 3.1. Synthesis of the PMF particles 70 3.2. Water treatment experiments with diclofenac solution 72 3.3. Theoretical model 72 3. Results and Discussion 73 3.1. Synthesis and characterization of the PMF particles 74 3.2. Adsorption of Pharmaceutics 80 4. Conclusion 84 7. Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles 89 Graphical Abstract 89 Abstract 89 1. Introduction 90 2. Materials and methods 91 2.1. Materials 91 2.2. Synthesis of the Poly(melamine-co-formaldehyde) particles 92 2.3. Methods 93 2.4. Water treatment experiments 96 3. Results and discussion 97 3.1. Synthesis and characterization of the PMF particles 98 3.2. Cu2+ uptake experiments 102 3.3. Mechanism for Cu2+ and Anion Removal 115 3.4. Investigation of other heavy metal salts 116 4. Conclusions 117 8. SiO₂ Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles 121 Graphical Abstract 121 Abstract 121 1. Introduction 122 2. Materials and methods 123 2.1. Materials 123 2.2. Methods 124 2.3. Synthesis of the PMF particles 125 2.4. Water treatment experiments 128 2.5. Theoretical model 129 3. Results and Discussion 132 3.1. PMF-Std 133 3.2. Influence of the reaction mixture composition 136 3.3. Variation of the process parameters 140 3.4. Conclusion on the templating mechanism for PMF-Std 146 3.5. Acquiring µm-sized porous PMF particles for adsorption application 149 3.6. Adsorption experiments with K2Cr2O7 solution 151 4. Conclusion 155 9. Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions 161 Graphical Abstract 161 Abstract 161 1. Introduction 162 2. Materials and methods 163 2.1. Materials 163 2.2. Synthesis 164 2.3. Characterization 166 2.4. Batch adsorption experiments 169 2.5. Calculation and theoretical models 170 3. Results and discussion 172 3.1. Synthesis and characterization of the polymer particles 172 3.2. Adsorption experiments with Ni2+, Cd2+, and Pb2+ onto P(3PT-F)-3L 178 4. Conclusions 184 10. Conclusion and Outlook 191 Contribution to Publications 197 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal 197 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal 198 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles 199 SiO₂ Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles 200 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions 201 Danksagung 203 Appendix 205 References 207 Eidesstattliche Versicherung 217 / Durch fortschreitende Industrialisierung und den schonungslosen Verbrauch natürlicher Rohstoffe übt der Mensch negativen Einfluss auf seinen Lebensraum aus. Insbesondere Wasser als Grundlage des Lebens und fast aller Prozesse unserer Wirtschaft wird durch eine übermäßige Nutzung und unzureichende Reinigung mit diversen Schadstoffen kontaminiert. Hierbei stellen Oxyanionen, Schwermetallionen und organische Schadstoffe ein hohes Risiko für aquatische Lebensräume und letztendlich auch den Menschen dar. Durch unzureichende Entfernung tragen sie außerdem zum Verlust nicht-erneuerbarer Rohstoffe für industrielle Kreisläufe bei. Durch eine meist geringe Effektkonzentration und potentielle Wechselwirkungen mit diversen Lebewesen ist die Entfernung vieler Verunreinigungen extrem wichtig, um bestehende Ökosysteme nicht weiter zu verändern. Adsorption stellt eine energieeffiziente Methode zur Entfernung dieser Schadstoffe durch hierfür geeignete Adsorbentien dar. Hochgradig vernetzte Harzpolymere wie Poly(melamin-co-formaldehyd) (PMF) stellen mit ihrer sehr hohen chemischen Beständigkeit, einer hohen Zahl funktioneller Gruppen und einfachen Herstellbarkeit einen vielversprechenden Ausgangspunkt für Adsorbentien dar. Diese Dissertation beschreibt die kolloidale, wässrige Synthese nanoporöser Harzpartikel (z. B. PMF) durch eine Templatierung mit SiO2 Nanopartikeln (SiO2 NPs), welche anschließend zur Adsorption von Wasserschadstoffen eingesetzt werden. Ein übergeordnetes Ziel dieser Arbeit besteht aus der Aufklärung des Mechanismus zur Partikel- und Porenbildung durch systematische Variation verschiedener Syntheseparameter. Mittels Elektronenmikroskopie, N2-Sorption und Partikelgrößenmessung wird die Morphologie, Größe und Porenstruktur der Partikel analysiert. Umfassende Untersuchungen ermöglichen somit, den Einfluss der einzelnen getesteten Syntheseparameter auf diese Eigenschaften zu bestimmen. Ein sehr wichtiges Ziel, besonders für eine zukünftige großtechnische Anwendbarkeit, ist dabei die kolloidale Herstellung uniformer Partikel, welche sowohl eine hohe geordnete Porosität als auch Partikeldurchmesser im Bereich einiger Mikrometer aufweisen. Dies ermöglicht einen Einsatz als durchströmbaren Festbett-Adsorber. Dieses Ziel ist eng mit der mechanistischen Aufklärung der Poren- und Partikelbildung in der Synthese verknüpft. Die hergestellten nanoporösen PMF-Partikel wurden nach ihrer Charakterisierung für verschiedene Adsorptionsanwendungen getestet. Um ein umfassendes Bild über die Einsetzbarkeit von PMF-Partikeln zu erhalten, sollen jeweils Versuche mit Oxyanionen, mit Schwermetallionen und mit Pharmazeutika als Vertreter organischer Schadstoffe durchgeführt werden. Bei diesen Versuchen steht zum einen die Untersuchung der Adsorptionsleistung und des Adsorptionsmechanismus des jeweiligen Schadstoffes an PMF im Vordergrund. Zum anderen wird durch die Verwendung verschiedener Partikel, bei welchen ein einzelner Syntheseparameter variiert wurde, der Einfluss der veränderten Porosität auf den Adsorptionsmechanismus untersucht. Sulfat- und Phosphationen wurden in der Klasse der Oxyanionen untersucht. Für beide Ionen wurden extrem hohe Abtrennraten nachgewiesen, welche bisherige kommerziell erhältliche Materialien signifikant übertraf. In Versuchen hinsichtlich einer potentiellen selektiven Adsorption und somit Trennung beider Spezies, zeigten die PMF/SiO2-Hybridpartikel, bei welchen das Templat noch nicht entfernt wurde, eine selektive Sulfatadsorption. Die Immobilisierung von Schwermetallionen wurde mit besonderem Fokus auf die gleichzeitig auftretende Abtrennung der dafür verwendeten Cu2+-Ionen und jeweiliger Anionen analysiert. Durch Untersuchungen des Adsorbens nach den Adsorptionsversuchen mittels Elektronenmikroskopie, Röntgenstreuung und Elektronenspinresonanz-Spektroskopie wurde der bisher unzureichend analysierte Adsorptionsmechanismus aufgeklärt. Hierbei wurden Adsorption und oberflächeninduzierte Fällung als separate Teilprozesse identifiziert, welche beide jeweils für die Abscheidung von sowohl Metall- als auch Anionen aus der Lösung verantwortlich sind. Bei Adsorptionsversuchen mit den einwertigen Ionen Nitrat und Chlorid wurde ein zweistufiger Prozess identifiziert, welcher erstmals über eine neue Adsorptionsisotherme mathematisch beschrieben wurde. Im Bereich organischer Wasserschadstoffe wird die Abtrennung des Pharmazeutikums Diclofenac getestet. Insbesondere die Adsorption von Pharmazeutika stellt aufgrund von deren geringen Effektkonzentration und Allgegenwärtigkeit in Oberflächen- und Leitungswässern ein dringliches Thema dar. Die Pharmazeutika-Abtrennung mittels PMF wurde trotz seiner vielversprechenden Eigenschaften weltweit bisher kaum untersucht. Im Rahmen dieser Versuche wurden Partikel getestet, welche mit unterschiedlich großen und unterschiedlich stabilisierten SiO2 NPs templatiert wurden. Dadurch entstanden Porensysteme, die besonders in derer Zugänglichkeit ihres Porensystems und in dem Durchmesser der Verbindungskanäle zwischen den Hauptkavitäten voneinander variierten. Diese Eigenschaften wirkten sich signifikant auf die Adsorptionskapazität und die Abtrennraten im niedrigen Konzentrationsbereich aus. Ein abschließendes Ziel ist die Synthese eines Harznetzwerkes, welches statt Melamin auf einem ebenso hochfunktionellen, triazinbasierten Monomer basiert. Das Monomer 2,4,6-Tris(2,4,6-trihydroxyphenyl)-1,3,5-triazin (3PT) besitzt jeweils neun Hydroxylgruppen, wodurch ein darauf basierendes Polymer stark veränderte Adsorptionseigenschaften gegenüber PMF aufweisen soll. Mit diesem Monomer wurde in einer analog zu PMF durchgeführten wässrigen Polymerisation ein bisher unbekanntes Polymernetzwerk hergestellt, welches als P(3PT-F) bezeichnet wurde. Hierbei wurde auf Templatierung verzichtet, da das neu hergestellte Material bereits intrinsische Nanoporosität durch die Größe des verwendeten 3PT-Monomers aufwies. In anschließenden Adsorptionsversuchen wurden sehr hohe Abtrennraten für die toxischen Metallion Pb2+, Cd2+ und Ni2+ nachgewiesen. In realistischen Ausgangskonzentrationen wurde die Kontamination mit diesen Ionen jeweils auf Trinkwasserqualität reduziert. P(3PT-F) zeigte außerdem eine sehr selektive Abtrennung von Pb2+ gegenüber den häufig vorkommenden Ionen Ca2+, Mg2+, K+ und Fe2+. Als grundlegender Beweis konnte eine Wiederverwendbarkeit durch die vollständige Desorption mit verdünnter HCl gezeigt werden und eine anschließende erneute Adsorption ohne signifikante Verringerung der Kapazität. Insgesamt wurde ausgehend von der grundlegenden Untersuchung der PMF-Partikelsynthese erst ein generelleres Verständnis der wässrigen Dispersionspolymerisation hydrophober Harze abgeleitet und die Templatierung mit hydrophilen SiO2 NPs implementiert. Mithilfe des Verständnisses der Partikelwachstumsprozesse und der Wechselwirkungen, welche für die Templatierung verantwortlich sind, konnten die Eigenschaften der entstehenden Partikel gesteuert werden. Im Rahmen der Adsorptionsuntersuchungen konnte anschließend der Einfluss insbesondere der veränderten Porosität auf die Abtrennleistung untersucht werden. Außerdem konnte analysiert werden, welche Wechselwirkungen PMF mit den jeweiligen Schadstoffarten eingeht. Durch den Austausch des Monomers Melamin gegen das hydroxylhaltiges Monomer 3PT konnte ein neuartiges Harzpolymer hergestellt werden. Dieses kann mit seiner veränderten Porosität und Reaktivität nun als neuer Ausgangspunkt für Adsorptionsexperimente mit stark veränderter Adsorptionsleistung z. B. gegenüber Schwermetallionen dienen.:Abstract 1 Kurzfassung 5 List of Publications 9 First-Author Publications 9 Co-Author Publications 10 Patent 12 Conference Proceedings 12 Oral Presentations 12 Poster 12 List of Figures 13 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal: 14 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal: 15 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles: 16 SiO2 Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles: 18 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions: 19 List of Tables 21 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal: 21 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal: 21 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles: 22 SiO2 Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles: 22 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions: 23 Abbreviations 25 Symbols 26 1. Introduction 1 2. Objectives and Experimental Design 5 3. Scientific Background 11 3.1. Poly(melamine-co-formaldehyde) 11 3.1.1. Polymerization Mechanism 11 3.1.2. Synthesis Strategies for the Preparation of Porous PMF Particles. 13 3.1.3. Fields of Application of PMF 13 3.2. Adsorption 15 3.2.1. Adsorption Isotherms and Mathematical Modeling 16 3.3. Surface Precipitation 20 4. Fundamentals of Instrumental Analytics 23 4.1. Gas Sorption Measurements 23 4.1.1. Determination of Pore Sizes 26 4.1.2. Determination of Specific Surface Area 27 4.2. Transmission Electron Microscopy 29 4.3. Inductively Coupled Plasma Optical Emission Spectroscopy 31 Results and Discussion 33 Chapter Overview 33 5. Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal 37 Graphical Abstract 37 Abstract 37 1. Introduction 38 2. Results and Discussion 39 2.1. Synthesis and Characterization of the PMF Particles 40 2.2. Sorption Experiments 47 3. Materials and Methods 54 3.1. Materials 54 3.2. Methods 54 3.3. Synthesis of the PMF Particles 56 3.4. Water Treatment Experiments 57 4. Conclusions 59 6. Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal 65 Graphical Abstract 65 Abstract 65 1. Introduction 66 2. Materials 68 3. Methods 68 3.1. Synthesis of the PMF particles 70 3.2. Water treatment experiments with diclofenac solution 72 3.3. Theoretical model 72 3. Results and Discussion 73 3.1. Synthesis and characterization of the PMF particles 74 3.2. Adsorption of Pharmaceutics 80 4. Conclusion 84 7. Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles 89 Graphical Abstract 89 Abstract 89 1. Introduction 90 2. Materials and methods 91 2.1. Materials 91 2.2. Synthesis of the Poly(melamine-co-formaldehyde) particles 92 2.3. Methods 93 2.4. Water treatment experiments 96 3. Results and discussion 97 3.1. Synthesis and characterization of the PMF particles 98 3.2. Cu2+ uptake experiments 102 3.3. Mechanism for Cu2+ and Anion Removal 115 3.4. Investigation of other heavy metal salts 116 4. Conclusions 117 8. SiO₂ Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles 121 Graphical Abstract 121 Abstract 121 1. Introduction 122 2. Materials and methods 123 2.1. Materials 123 2.2. Methods 124 2.3. Synthesis of the PMF particles 125 2.4. Water treatment experiments 128 2.5. Theoretical model 129 3. Results and Discussion 132 3.1. PMF-Std 133 3.2. Influence of the reaction mixture composition 136 3.3. Variation of the process parameters 140 3.4. Conclusion on the templating mechanism for PMF-Std 146 3.5. Acquiring µm-sized porous PMF particles for adsorption application 149 3.6. Adsorption experiments with K2Cr2O7 solution 151 4. Conclusion 155 9. Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions 161 Graphical Abstract 161 Abstract 161 1. Introduction 162 2. Materials and methods 163 2.1. Materials 163 2.2. Synthesis 164 2.3. Characterization 166 2.4. Batch adsorption experiments 169 2.5. Calculation and theoretical models 170 3. Results and discussion 172 3.1. Synthesis and characterization of the polymer particles 172 3.2. Adsorption experiments with Ni2+, Cd2+, and Pb2+ onto P(3PT-F)-3L 178 4. Conclusions 184 10. Conclusion and Outlook 191 Contribution to Publications 197 Mesoporous Poly(Melamine-co-Formaldehyde) Particles for Efficient and Selective Phosphate and Sulfate Removal 197 Tuning the Pore Structure of Templated Mesoporous Poly(melamine-co-formaldehyde) Particles toward Diclofenac Removal 198 Adsorption vs. Surface Precipitation of Cu²+ onto Porous Poly(melamine-co-formaldehyde) Particles 199 SiO₂ Nanospheres as Surfactant and Template in Aqueous Dispersion Polymerizations Yielding Nanoporous Resin Particles 200 Waterborne Phenolic, Triazine-Based Porous Polymer Particles for the Removal of Nickel, Cadmium, and Lead Ions 201 Danksagung 203 Appendix 205 References 207 Eidesstattliche Versicherung 217