A Complementary and Revised View on the N-Acylation of Chitosan with Hexanoyl Chloride

The modification of the biobased polymer chitosan is a broad and widely studied field. Herein, an insight into the hydrophobization of low-molecular-weight chitosan by substitution of amino functionalities with hexanoyl chloride is reported. Thereby, the influence of the pH of the reaction media was investigated. Further, methods for the determination of the degree of substitution based on 1H-NMR, FTIR, and potentiometric titration were compared and discussed regarding their accuracy and precision. 1H-NMR was the most accurate method, while FTIR and the potentiometric titration, though precise and reproducible, underlie the influence of complete protonation and solubility issues. Additionally, the impact of the pH variation during the synthesis on the properties of the samples was investigated by Cd2+ sorption experiments. The adjusted pH values during the synthesis and, therefore, the obtained degrees of substitution possessed a strong impact on the adsorption properties of the final material

Waterborne phenolic, triazine-based porous polymer particles for the removal of toxic metal ions

Highly functional and also highly porous materials are presenting great advantages for applications in energy storage, catalysis and separation processes, which is why a continuous development of new materials can be seen. To create a material combining the promising potential interactions of triazine groups with the electrostatic or hydrogen bonding interactions of phenolic groups, a completely new polymeric resin was synthesized. From an eco-friendly dispersion polymerization in water, a copolymer network was obtained, which includes nine hydroxyl groups and one s-triazine ring per repetition unit. The polymer forms highly porous particles with specific surface areas up to 531 ​m2/g and a negative streaming potential over a great pH range. The adsorption isotherms of Ni2+, Cd2+, and Pb2+ were studied in more detail achieving very good adsorption capacities (16 mg Ni2+/g, 24 mg Cd2+/g, and 90 mg Pb2+/g). Demonstrating excellent properties for adsorption applications. The adsorbent exhibited selectivity for the adsorption of Pb2+ over more commonly occurring but non-toxic metal ions such as Fe2+, Ca2+, Mg2+, and K+. Furthermore, reusability of the material was demonstrated by facile, quantitative desorption of adsorbed Pb2+ with a small amount of diluted HCl, circumventing organic chelators. Subsequently, adsorption was carried out without decrease in adsorption performance

Web Data Extraction, Applications and Techniques: A Survey

Web Data Extraction is an important problem that has been studied by means of different scientific tools and in a broad range of applications. Many approaches to extracting data from the Web have been designed to solve specific problems and operate in ad-hoc domains. Other approaches, instead, heavily reuse techniques and algorithms developed in the field of Information Extraction. This survey aims at providing a structured and comprehensive overview of the literature in the field of Web Data Extraction. We provided a simple classification framework in which existing Web Data Extraction applications are grouped into two main classes, namely applications at the Enterprise level and at the Social Web level. At the Enterprise level, Web Data Extraction techniques emerge as a key tool to perform data analysis in Business and Competitive Intelligence systems as well as for business process re-engineering. At the Social Web level, Web Data Extraction techniques allow to gather a large amount of structured data continuously generated and disseminated by Web 2.0, Social Media and Online Social Network users and this offers unprecedented opportunities to analyze human behavior at a very large scale. We discuss also the potential of cross-fertilization, i.e., on the possibility of re-using Web Data Extraction techniques originally designed to work in a given domain, in other domains.Comment: Knowledge-based System

Materials in particulate form for tissue engineering. 1 Basic concepts

For biomedical applications, materials small in size are growing in importance. In an era where ‘nano’ is the new trend, micro- and nano-materials are in the forefront of developments. Materials in the particulate form aim to designate systems with a reduced size, such as micro- and nanoparticles. These systems can be produced starting from a diversity of materials, of which polymers are the most used. Similarly, a multitude of methods are used to produce particulate systems, and both materials and methods are critically reviewed here. Among the varied applications that materials in the particulate form can have, drug delivery systems are probably the most prominent, as these have been in the forefront of interest for biomedical applications. The basic concepts pertaining to drug delivery are summarized, and the role of polymers as drug delivery systems conclude this review

The Effects of Tamoxifen on Plasma Lipoprotein(a) Concentrations: Systematic Review and Meta-Analysis

Introduction: Tamoxifen is a selective estrogen receptor modulator widely used in the treatment of breast cancer. Tamoxifen therapy is associated with reduced circulating low-density lipoprotein cholesterol and increased triglycerides, but its effects on other lipids are less-well studied. Aims: We aimed to investigate the effect of tamoxifen on circulating concentrations of lipoprotein(a) (Lp(a)) through systematic review and meta-analysis of available randomized controlled trials (RCTs) and observational studies. Methods: This study was registered in the PROSPERO database (CRD42016036890). Scopus, Medline and EMBASE were searched from inception until 22nd March 2016 to identify studies investigating the effect of tamoxifen on Lp(a) values in humans. Results: Meta-analysis of 5 studies with 284 participants suggested a significant reduction of Lp(a) levels following tamoxifen treatment (weighted mean difference [WMD]: -3.53 mg/dL, 95% confidence interval [CI]: -6.53, -0.53, p=0.021). When studies were categorized according tamoxifen dose, there was a significant effect in the subset of studies with administered doses ≥20 mg/day (WMD: -5.05 mg/dL, 95% CI: -7.86, -2.23, p<0.001), but not in the subset with doses <20 mg/day (WMD: -1.41 mg/dL, 95% CI: -5.13, 2.31, p=0.458). With respect to duration of treatment, a greater effect was observed in subgroup of studies administering tamoxifen for <12 weeks (WMD: -4.01 mg/dL, 95% CI: -7.84, -0.18, p=0.04) versus the subgroup of studies lasting ≥12 weeks (WMD: -2.48 mg/dL, 95% CI: -5.50, 0.53, p=0.107). Conclusions: Meta-analysis suggested a significant reduction of Lp(a) levels following tamoxifen treatment. Further well-designed trials are required to validate these results

Synthesis and Characterization of Hybrid Materials Based on Conjugated Microporous Polymers

Das Ziel der Arbeit war die Kombination von 1,3,5-Triethynylbenzen (TEB)-basierten konjugierten mikroporösen Polymeren (CMPs) mit den unterschiedlichen Materialien Silica, Chitosan und Silizium um Hybridmaterialien herzustellen. Als Grundprämisse galt dabei die anwendungsorientierte Verbesserung der Eigenschaften, wobei sich an den literaturbekannten Hauptanwendungen von CMPs – als Adsorber oder als Photokatalysator – orientiert wurde. Die Optimierung von Hybridmaterialien erfordert drei Grundvoraussetzungen: Genaue Kenntnisse der CMPs, dasselbe Verständnis von den Eigenschaften der zu kombinierenden Materialien und die Möglichkeit der umfassenden Charakterisierung. Nur unter diesen Voraussetzungen lassen sich die kollektiven und die aus der Kombination entstehenden Eigenschaften des Hybridmaterials definiert einstellen. Die erste Studie ist der Grundvoraussetzung, der Struktur-Eigenschaftsbeziehung in CMPs, gewidmet. Dabei wurden neuartige CMPs auf Basis von TEB gekuppelt mit Dibromophenanthren-diol Monomeren hergestellt (Polymer TEB-Phenanthren =PTPh). Diese Monomere wurden über die Diolgruppe mit Methyl-(OMe), Trimethylsilyl- (TMS) oder Tertbutyldimethylsilyl (TBDMS) funktionalisiert, wodurch eine homologe Reihe mit steigendem sterischen Anspruch und variierender Polarität entstand. Diese Monomere wurden jeweils mit TEB zu CMPs umgesetzt, um den Einfluss der Sterik auf die CMP Eigenschaften zu analysieren. Über dynamische Kontaktwinkelmessung wurde ermittelt, dass mit Ausnahme von PTPh-TMS, alle PTPh-CMPs mit Kontaktwinkeln zwischen 136° und 148° stark hydrophob sind. Für PTPh-TBDMS ergab sich eine weitere ungewöhnliche Eigenschaft: entgegen den klassischen CMP-Eigenschaften, war es in hydrophoben Lösungsmitteln löslich. Aus Kernspinresonanzspektroskopie (NMR), dynamischen Lichtstreuungs- (DLS) und Transmissionselektronenmikroskop- (TEM) Messungen ging hervor, dass es in Form gequollener, stärker vernetzter Nanopartikel vorliegt, die von weniger vernetztem, quasi-linearem Polymer kolloidal stabilisiert werden. Für potentielle Anwendungen in der Sensortechnik ist dabei relevant, dass dieses PTPh-TBDMS bei einer Anregung mit Licht von 400 nm fluoreszierende Eigenschaften aufweist. Die zweite Studie befasst sich mit dem ersten Hybridmaterial aus mesoporösen Silica-Mikrosphären (40 – 70 µm Durchmesser) ummantelt mit CMPs zur Adsorption organischer Schadstoffe. Während die CMPs in ihren Funktionalitäten genau auf die zu adsorbierende Substanz eingestellt werden können, verbessern die SiO2 Partikel die Dispergierbarkeit und die technische Handhabung der ansonsten schwierig abzutrennenden CMPs. In der ersten Teilstudie wurde das literaturbekannte CMP aus Dibromopyrimidin und TEB (CMP = Polymer TEB Pyrimidin = PTP) für die Ummantelung verwendet. Die in der Synthese eingesetzte Menge an SiO2 beeinflusst die Adsorption des Diclofenacs (DCF), eines weitverbreiteten Pharmazeutikums, welches als Modelladsorptiv verwendet wurde. Die ermittelten maximalen Beladungskapazitäten zeigen ein Maximum bei 3.0 g Silica auf die Standardmenge CMP. Das Silica selbst adsorbiert DCF in vernachlässigbaren Mengen, weshalb die CMP-spezifische Kapazität aus dem tatsächlich im Material enthaltenen CMP-Massenanteil (Thermogravimetrische Analyse (TGA) -Bestimmung) berechnet wurde. Hier ergibt sich für das Maximum bei 3.0 g Silica eine maximale Beladung von 422 mg DCF pro Gramm CMP, welche mit den besten bekannten Adsorbern konkurrieren kann. In der zweiten Teilstudie wurde das Prinzip der Silicasphären-Ummantelung auf andere CMPs aus jeweils TEB und Dibromonaphtalen, Dibromoanilin und Dibromopyridin übertragen. Es konnte gezeigt werden, dass die Monomerpolarität starken Einfluss auf den Erfolg der Ummantelung hat: Nur bei gleicher Polarität von Monomer und Silicaoberfläche war eine Beschichtung möglich. Mittels Präfunktionalisierung des Silicas war eine Ummantelung auch für die hydrophoberen Monomere möglich. Diese Beschichtungen wurden mit Fourier-Transformations-Infrarotspektroskopie (FTIR), Festkörper-NMR, REM, REM-EDX, TGA und TEM analysiert. Im Anschluss wurde erneut die DCF-Adsorption untersucht, wobei das Dibromoanilin basierte CMP@SiO2 die höchste CMP-spezifische DCF-Adsorptionskapazität mit 228 mg/g lieferte. Ein anderes Hybridmaterial, bestehend aus den in der ersten Studie entwickelten CMPs eingebettet in das biobasierte Polymer Chitosan, wird in der dritten Studie thematisiert. Das Ziel war, analog zu den vorhergehenden Studien, eine bessere Verteilung und Zugänglichkeit der CMPs für Adsorptive bei gleichzeitiger Retention in definierten Strukturen zur Vereinfachung der Handhabung. Chitosan als biobasiertes und biokompatibles Polymer ist vergleichsweise nachhaltig, ermöglicht medizinische Applikationen und ist gut über die Aminogruppe funktionalisierbar. Daher wurde die Aminofunktionalität mit Hexanoylchlorid umgesetzt, um eine hydrophobe Hexanoylgruppe in das Chitosan einzuführen. Das modifizierte Hexanoyl Chitosan (H-chitosan) wurde auf verschiedene Weise analysiert, wobei besonders die Änderung der rheologischen Eigenschaften aufgrund der Unterbrechung der Wasserstoffbrückenbindung zwischen den Chitosanketten durch die hydrophobe Modifizierung bedeutend waren. Anschließend wurden sowohl das reine Chitosan als auch das H-chitosan verwendet, um CMP@Chitosan Gel-Beads herzustellen. Da das CMP das teurere Material ist, wurde es im Massenverhältnis von 1:4 eingesetzt, wobei über REM und REM-EDX nachgewiesen wurde, dass die CMPs großflächig in den Chitosanmatrizen verteilt sind. Beim Trocknen wurde beobachtet, dass die luftgetrockneten Beads zu kompakten Strukturen kollabieren, während die vakuumgetrockneten Beads die gequollene Form beibehalten. Dies wirkt sich auf die Quellung der trockenen Beads im wässrigen Adsorptionsmedium aus, wobei die luftgetrockneten Beads nur geringfügig und die vakuumgetrockneten Beads deutlich stärker quellen. Dabei quellen die H-chitosan Beads generell besser, was auf die gehinderte Zusammenlagerung der Chitosanketten durch die hydrophobe Gruppe zurückgeführt wurde. Mittels Batchversuchen wurde die Adsorption von DCF bei einer niedrigen Konzentration von 1 mg/L und einer hohen Konzentration von 300 mg/L untersucht, wobei sich die vakuumgetrockneten Beads als effektiver erwiesen. Die Hybridmaterialbeads adsorbierten mehr DCF als sowohl die reinen Chitosan- bzw. H-chitosan Beads als auch die reinen CMPs. Die CMP@H-chitosan Beads adsorbierten aufgrund der verbesserten Quellung die höchsten Mengen an DCF. Die CMP-spezifische Adsorption wurde durch die Einbindung und Verteilung in den Chitosanmatrizen deutlich gesteigert, während gleichzeitig die Handhabbarkeit erleichtert wurde, da die Beads mittels eines Siebes aus der Adsorptionslösung abgetrennt werden können. Die letzte Studie ist auf Silizium-Nanopartikel (SiNPs)@CMP-Hybridmaterialien zur Anwendung als Photokatalysator in der solaren Wasserstoffgenerierung (HER) ausgerichtet. In diesem Prozess wird solare Energie direkt genutzt, um aus Wasser Wasserstoff herzustellen. Die für CMP-typischen geringen HER-Raten sollen durch die, von der AG Dasog (Dalhousie Universität, Halifax, Kanada) hergestellten, SiNPs angehoben werden. Mittels FTIR Spektroskopie wurde bestätigt, dass diese CMPs auch im Beisein der SiNPs gebildet wurden. Über TGA wurde der Massenanteil der SiNPs in den jeweiligen Hybridmaterialien bestimmt, welcher von 4 wt% bis 22 wt% variiert und vor allem vom eingesetzten Monomer abhängt. REM-EDX Analysen zeigten eine lösungsmittelunabhängige, flächendeckende Verteilung der SiNPs in den jeweiligen CMPs. Die Einbindung der SiNPs, analysiert über DLS und TEM Messungen, ergab in einem Fall eine vollständige Einbindung, in einem anderen Fall eine schlechte Einbindung und in allen übrigen Fällen partielle Einbindung. Diese partielle Einbindung, bei der Teile der SiNPs nicht mit CMP bedeckt sind, erwies sich als vorteilhaft in den Wasserstoffgenerierungsversuchen. Bei diesen SiNP@CMP Hybridmaterialien waren die HER Raten gegenüber den reinen CMPs deutlich gesteigert, wobei das beste Material 32 µmol/g*h Wasserstoff produzierte. Dieses Material wurde durch Dotierung mit H2PtCl4 weiter optimiert und in Zyklisierungsstudien eingesetzt. Während die Langzeitstabilität sich als optimierungsbedürftig erwies, war die Dotierung erfolgreich und steigerte die HER Rate auf 42 µmol/g*h. Im Rahmen dieser Arbeit wurden CMPs mit je einem Vertreter der anorganischen Isolatoren, der biobasierten Polymere und der anorganischen Halbleiter kombiniert. Die grundlegende Unterschiedlichkeit dieser Materialien zeigt, dass der Kombinationsvielfalt nur wenige Limitationen gesetzt sind. Die anwendungsbezogenen Machbarkeitsstudien zeigen die daraus erwachsenden Vorteile auf. Dabei befindet sich die Erforschung der CMP-Hybridmaterialien noch in ihren Anfängen, enthält jedoch bereits vielversprechende Strategien und Ansätze zur Lösung gesellschaftlich relevanter Problemstellungen.:Abstract V Kurzfassung VIII Abbreviations XI Symbols XII List of publications XIII List of figures XVI List of schemes XVIII List of tables XIX 1. Introduction 1 2. Theoretical background 4 2.1. Synthesis and properties of conjugated microporous polymers (CMPs) 4 2.1.1. Conjugated microporous polymers - a new class of materials 4 2.1.2. Synthesis of CMPs 5 2.1.3. Properties of CMPs 8 2.2. Fundamentals of adsorption and application of CMPs as adsorbers 11 2.2.1. Basic adsorption models 12 2.2.2. CMPs as adsorbers 16 2.3. Fundamentals and application of CMPs for hydrogen evolution 19 2.3.1. Physicochemical fundamentals of photocatalysis 19 2.3.2. Reaction and conditions of solar-driven hydrogen evolution 22 2.3.3. CMPs for solar-driven hydrogen evolution 24 2.4. Hybrid materials based on CMPs 26 2.4.1. CMPs combined with nanoparticulate systems 26 2.4.2. Macroscale CMP-based hybrid materials 30 2.5. Fundamentals of instrumental analysis 31 2.5.1. Fourier transform infrared spectroscopy 31 2.5.2. Nuclear magnetic resonance 34 2.5.3. Gas sorption analysis 37 3. Results and discussion 41 3.1. Synthesis and characterization of conjugated microporous polymers 41 3.1.1. Dibromophenanthrene-based monomers 42 3.1.2. CMPs of the basic monomers 43 3.1.3. CMPs of the functionalized monomers 46 3.1.4. Properties of the PTPh-CMPs 48 3.1.5. PTPh-TBDMS - a special case 50 3.2. CMP@Silica microspheres 52 3.2.1. Conjugated Microporous Polymer Hybrid Microparticles for Enhanced Applicability in Silica-boosted Diclofenac Adsorption 53 3.2.2. Polarity and Functionality Tailored Conjugated Microporous Polymer Coatings on Silica Microspheres for Enhanced Pollutant Adsorption 71 3.3. CMP@Chitosan 86 3.3.1. A Complementary and Revised View on the N-Acylation of Chitosan with Hexanoyl Chloride 88 3.3.2. CMP@Chitosan synthesis and characterization 106 3.3.3. Diclofenac adsorption of CMP@Chitosan beads 110 3.4. Silicon nanoparticles@CMPs 115 3.4.1. New materials for solar-driven hydrogen evolution 115 3.4.2. Synthesis and characterization of selected SiNP@CMP hybrid materials 116 3.4.3. Distribution and incorporation of SiNPs in the CMP matrices 121 3.4.4. Hydrogen evolution reaction 124 4. Experimental section 128 4.1. Synthesis 128 4.1.1. Synthesis of the CMPs 129 4.1.2. Synthesis of dibromo-phenanthrene based monomers 129 4.1.3. Synthesis of CMP@Chitosan beads 131 4.1.4. Synthesis of the SiNP@CMP hybrid materials 132 4.2. Characterization and application-related studies 133 4.2.1. Characterization of the PTPh-monomers and CMPs 133 4.2.2. Characterization of the CMP@Chitosan beads 133 4.2.3. Characterization of the SiNP@CMP 134 5. Conclusion and outlook 135 6. References 141 7. Appendix 151 DanksagungThe thesis aimed to combine 1,3,5-triethynylbenzene (TEB)-based conjugated microporous polymers (CMPs) with the different materials silica, chitosan, and silicon to produce hybrid materials. The basic premise was an application-oriented improvement of properties, guided by the main applications of CMPs known from the literature - as adsorbers or as photocatalysts. Optimization of hybrid materials requires three basic prerequisites: Precise knowledge of the CMPs, the same understanding of the properties of the materials to be combined, and the possibility of comprehensive characterization. Only under these conditions the collective properties and those resulting from the combination of the hybrid material can be adjusted in a defined way. The first study is devoted to the basic premise, the structure-property relationship in CMPs. Here, novel CMPs based on TEB coupled with dibromo phenanthrene-diol monomers were prepared (polymer TEB-phenanthrene =PTPh). These monomers were functionalized with methyl-(OMe), trimethylsilyl- (TMS), or tertbutyldimethylsilyl (TBDMS) via the diol group, resulting in a homologous series with increasing steric demand and varying polarity. These monomers were each coupled with TEB to form CMPs in order to analyze the influence of steric demand on the CMP properties. Via dynamic contact angle measurement, it was determined that except PTPh-TMS, all PTPh-CMPs are highly hydrophobic with contact angles between 136° and 148°. For PTPh-TBDMS, another unusual property emerged: Contrary to the classical CMP properties, it was soluble in hydrophobic solvents. From nuclear magnetic resonance (NMR), dynamic light scattering (DLS), and transmission electron microscopy (TEM) measurements, it was found to consist of swollen, more cross-linked nanoparticles colloidally stabilized by less cross-linked quasi-linear polymer. Further, PTPh-TBDMS exhibits fluorescent properties when excited with light at 400 nm, which is of relevance to potential applications in sensor technology. The second study deals with the first hybrid material consisting of mesoporous silica microspheres (40 – 70 µm diameter) coated with CMPs for the adsorption of organic pollutants. While the functionalities of the CMPs can be precisely adjusted to interact with the pollutant, the SiO2 particles improve dispersibility and technical handling of the CMP that is otherwise difficult to recover. The first sub-study used the literature-known CMP of dibromo pyrimidine and TEB (CMP = polymer TEB pyrimidine = PTP) for the coating. From scanning electron microscopy (SEM) images, it can be seen that the PTP grows on the SiO2 spheres in the form of hemispheres. The amount of SiO2 used in the synthesis affects the adsorption of diclofenac (DCF), a widely applied pharmaceutical used as a model adsorptive. The maximum loading capacities determined show a maximum at 3.0 g of silica to the standard amount of CMP. The silica itself adsorbs DCF in negligible amounts, which is why the CMP-specific capacity was calculated from the CMP mass fraction actually contained in the material (thermogravimetric analysis -TGA determination). Here, the maximum loading at 3.0 g silica is 422 mg DCF per gram CMP, which is competitive with the best-known adsorbents. In the second sub-study, the principle of silica sphere coating was transferred to other CMPs from TEB and dibromo naphthalene, dibromo aniline, and dibromo pyridine, respectively. It was shown that the monomer polarity has a strong influence on the success of the coating: The coating was only possible if the monomer and the silica surface featured the same polarity. Through pre-functionalization of the silica, the coating was also made possible for the more hydrophobic monomers. Fourier transform infrared spectroscopy (FTIR), solid-state NMR, SEM, SEM-EDX, TGA, and TEM were used to analyze these coatings. DCF adsorption was then investigated, with the dibromo aniline-based CMP@SiO2 providing the highest CMP-specific DCF adsorption capacity of 228 mg/g. Another hybrid material, consisting of the CMPs developed in the first study embedded in the biobased polymer chitosan, is investigated in the third chapter. The goal, analogous to the previous studies, was to improve the distribution and accessibility of the CMPs for adsorptives while retaining them in defined structures for ease of handling. As a biobased and biocompatible polymer, chitosan is comparatively sustainable, enables medical applications, and is well-functionalizable via the amino group. Therefore, the amino functionality was converted with hexanoyl chloride to introduce a hydrophobic hexanoyl group into the chitosan. The modified hexanoyl chitosan (H-chitosan) was analyzed in several ways. The change in rheological properties due to the disruption of hydrogen bonding between the chitosan chains by the hydrophobic modification was particularly significant. Subsequently, the pure chitosan and the H-chitosan were used to prepare CMP@Chitosan gel beads. Since the CMP is the more expensive material, it was used in a mass ratio of 1:4. It was verified via SEM and SEM-EDX that the CMPs were distributed over a large area in the chitosan matrices. Upon drying, it was observed that the air-dried beads collapsed into compact structures, while the vacuum-dried beads retained the swollen shape. This affects the swelling of the dry beads in the aqueous adsorption medium, with the air-dried beads swelling only slightly and the vacuum-dried beads swelling significantly stronger. In general, the H-chitosan beads swell better, which was attributed to the hydrophobic group's hindered assembly of the chitosan chains. Batch experiments were used to investigate the adsorption of DCF at a low concentration of 1 mg/L and a high concentration of 300 mg/L, in which the vacuum-dried beads were found to be more effective. The hybrid material beads adsorbed more DCF than pure chitosan or H-chitosan beads and the pure CMPs. The CMP@H-chitosan beads adsorbed the highest amounts of DCF due to improved swelling. Overall, the CMP-specific adsorption was significantly enhanced by incorporation and distribution in the chitosan matrices. At the same time, handling was facilitated because the beads can be separated from the adsorption solution using a sieve and do not need to be centrifuged like the CMPs. The final study is focused on silicon nanoparticles (SiNPs)@CMP hybrid materials for use as photocatalysts in solar-driven hydrogen evolution reaction (HER). In this process, solar energy is directly used to produce hydrogen from water. The low HER rates typical for CMPs are to be raised by the SiNPs produced by the Dasog group (Dalhousie University, Halifax, Canada). In turn, the SiNPs are to be protected from oxidative influences by the CMPs. For this purpose, the CMPs known from the literature and investigated in the previous studies were used. By FTIR, it was confirmed that all CMPs were also formed in the presence of the SiNPs. Via TGA, the mass fraction of SiNPs in the respective hybrid materials was determined, which varied from 4 wt% to 22 wt% and depended mainly on the monomer used. SEM-EDX analyses showed a solvent-independent, areal distribution of SiNPs in the respective CMPs. The incorporation of the SiNPs analyzed via DLS and TEM measurements showed complete incorporation in one case, poor incorporation in another, and partial incorporation in all other cases. This partial incorporation, where parts of the SiNPs are not covered with CMP, proved beneficial in the hydrogen evolution experiments. For these SiNP@CMP hybrid materials, the HER rates were significantly increased compared to the pure CMPs, with the best material producing 32 µmol/g*h of hydrogen. This material was further optimized by doping with H2PtCl4 and used in cyclization studies. While long-term stability proved to require more optimization, doping was successful as it increased the HER rate to 42 µmol/g*h. In this work, CMPs were combined with one representative of inorganic insulators, biobased polymers, and inorganic semiconductors. The fundamental difference between these materials shows that there are few limitations set to the variety of combinations. The application-related feasibility studies showed the advantages that arise from this. Although research into CMP hybrid materials is still in its infancy, it already holds promising strategies and approaches for solving socially relevant problems.:Abstract V Kurzfassung VIII Abbreviations XI Symbols XII List of publications XIII List of figures XVI List of schemes XVIII List of tables XIX 1. Introduction 1 2. Theoretical background 4 2.1. Synthesis and properties of conjugated microporous polymers (CMPs) 4 2.1.1. Conjugated microporous polymers - a new class of materials 4 2.1.2. Synthesis of CMPs 5 2.1.3. Properties of CMPs 8 2.2. Fundamentals of adsorption and application of CMPs as adsorbers 11 2.2.1. Basic adsorption models 12 2.2.2. CMPs as adsorbers 16 2.3. Fundamentals and application of CMPs for hydrogen evolution 19 2.3.1. Physicochemical fundamentals of photocatalysis 19 2.3.2. Reaction and conditions of solar-driven hydrogen evolution 22 2.3.3. CMPs for solar-driven hydrogen evolution 24 2.4. Hybrid materials based on CMPs 26 2.4.1. CMPs combined with nanoparticulate systems 26 2.4.2. Macroscale CMP-based hybrid materials 30 2.5. Fundamentals of instrumental analysis 31 2.5.1. Fourier transform infrared spectroscopy 31 2.5.2. Nuclear magnetic resonance 34 2.5.3. Gas sorption analysis 37 3. Results and discussion 41 3.1. Synthesis and characterization of conjugated microporous polymers 41 3.1.1. Dibromophenanthrene-based monomers 42 3.1.2. CMPs of the basic monomers 43 3.1.3. CMPs of the functionalized monomers 46 3.1.4. Properties of the PTPh-CMPs 48 3.1.5. PTPh-TBDMS - a special case 50 3.2. CMP@Silica microspheres 52 3.2.1. Conjugated Microporous Polymer Hybrid Microparticles for Enhanced Applicability in Silica-boosted Diclofenac Adsorption 53 3.2.2. Polarity and Functionality Tailored Conjugated Microporous Polymer Coatings on Silica Microspheres for E

Thermoresponsive Catechol Based-Polyelectrolyte Complex Coatings for Controlled Release of Bortezomib

To overcome the high relapse rate of multiple myeloma (MM), a drug delivery coating for functionalization of bone substitution materials (BSM) is reported based on adhesive, catechol-containing and stimuli-responsive polyelectrolyte complexes (PECs). This system is designed to deliver the MM drug bortezomib (BZM) directly to the anatomical site of action. To establish a gradual BZM release, the naturally occurring caffeic acid (CA) is coupled oxidatively to form poly(caffeic acid) (PCA), which is used as a polyanion for complexation. The catechol functionalities within the PCA are particularly suitable to form esters with the boronic acid group of the BZM, which are then cleaved in the body fluid to administer the drug. To achieve a more thorough control of the release, the thermoresponsive poly(N-isoproplyacrylamide-co-dimethylaminoethylmethacrylate) (P(NIPAM-co-DMAEMA)) was used as a polycation. Using turbidity measurements, it was proven that the lower critical solution temperature (LCST) character of this polymer was transferred to the PECs. Further special temperature dependent attenuated total reflection infrared spectroscopy (ATR-FTIR) showed that coatings formed by PEC immobilization exhibit a similar thermoresponsive performance. By loading the coatings with BZM and studying the release in a model system, via UV/Vis it was observed, that both aims, the retardation and the stimuli control of the release, were achieved. © 2019 by the authors. Licensee MDPI, Basel, Switzerland

Thermoresponsive Catechol Based-Polyelectrolyte Complex Coatings for Controlled Release of Bortezomib

To overcome the high relapse rate of multiple myeloma (MM), a drug delivery coating for functionalization of bone substitution materials (BSM) is reported based on adhesive, catechol-containing and stimuli-responsive polyelectrolyte complexes (PECs). This system is designed to deliver the MM drug bortezomib (BZM) directly to the anatomical site of action. To establish a gradual BZM release, the naturally occurring caffeic acid (CA) is coupled oxidatively to form poly(caffeic acid) (PCA), which is used as a polyanion for complexation. The catechol functionalities within the PCA are particularly suitable to form esters with the boronic acid group of the BZM, which are then cleaved in the body fluid to administer the drug. To achieve a more thorough control of the release, the thermoresponsive poly(N-isoproplyacrylamide-co-dimethylaminoethylmethacrylate) (P(NIPAM-co-DMAEMA)) was used as a polycation. Using turbidity measurements, it was proven that the lower critical solution temperature (LCST) character of this polymer was transferred to the PECs. Further special temperature dependent attenuated total reflection infrared spectroscopy (ATR-FTIR) showed that coatings formed by PEC immobilization exhibit a similar thermoresponsive performance. By loading the coatings with BZM and studying the release in a model system, via UV/Vis it was observed, that both aims, the retardation and the stimuli control of the release, were achieved

Switchable Release of Bone Morphogenetic Protein from Thermoresponsive Poly(NIPAM-<i>co</i>-DMAEMA)/Cellulose Sulfate Particle Coatings

Thermoresponsive coatings of poly(<i>N</i>-isopropylacrylamide-<i>co</i>-DMAEMA)/cellulose sulfate (PNIPAM-DMAEMA/CS) complexes are reported eluting bone-morphogenetic-protein-2 (BMP-2) on demand relevant for implant assisted local bone healing. PNIPAM-DMAEMA/CS dispersions contained colloid particles with hydrodynamic radii R_H = 170&#8315;288 nm at T = 25 &#176;C shrinking to R_H = 74&#8315;103 nm at T = 60 &#176;C. Obviously, PNIPAM-DMAEMA/CS undergoes volume phase transition (VPT) analogously to pure PNIPAM, when critical VPT temperature (VPTT) is exceeded. Temperature dependent turbidity measurements revealed broad VPT and VPTT 47 &#176;C for PNIPAM-DMAEMA/CS colloid dispersions at pH = 7.0. FTIR spectroscopy on thermoresponsive PNIPAM-DMAEMA/CS particle coatings at germanium model substrates under HEPES buffer indicated both wet-adhesiveness and VPT behavior based on diagnostic band intensity increases with temperature. From respective temperature courses empirical VPTT &#8776; 42 &#176;C for PNIPAM-DMAEMA/CS coatings at pH = 7.0 were found, which were comparable to VPTT found for respective dispersions. Finally, the PNIPAM-DMAEMA/CS coatings were loaded with BMP-2 and model protein papain (PAP). Time dependent FTIR spectroscopic measurements showed, that for T = 37 &#176;C there was a relative protein release of &#8776;30% for PAP and &#8776;10% for BMP-2 after 24 h, which did not increase further. Heating to T = 42 &#176;C for PAP and to 47 &#176;C for BMP-2 further secondary protein release of &#8776;20% after 24 h was found, respectively, interesting for clinical applications. BMP-2 eluted even at 47 &#176;C was found to be still biologically active