Hierarchically Structured Composite Materials by Gluing of Anisotropic Nanoparticles

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Hierarchically Structured Composite Materials by Gluing of Anisotropic Nanoparticles

Dissertation

zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften (Dr. rer. nat.)

an der Universität Konstanz

Mathematisch – Naturwissenschaftliche Sektion Fachbereich Chemie

vorgelegt von Ulrich Tritschler

Tag der mündlichen Prüfung: 18. Mai 2015 1. Referent: Prof. Dr. Helmut Cölfen 2. Referent: Prof. Dr. Stefan Mecking 3. Referent: Prof. Dr. Helmut Schlaad

Konstanzer Online-Publikations-System (KOPS) URL: http://nbn-resolving.de/urn:nbn:de:bsz:352-0-294543

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iii Diese Arbeit wurde im Zeitraum von Mai 2011 bis September 2014 im Fachbereich Chemie an der Universität Konstanz in der Arbeitsgruppe von Herrn Prof. Dr. Helmut Cölfen angefertigt.

Die Arbeit wurde so aufgebaut, dass jedes Kapitel für sich alleine gelesen werden kann. Jedes Kapitel beginnt mit einer kurzen Zusammenfassung sowie einer Einleitung, die dem Leser die jeweils nötigen Hintergrundinformationen gibt und in der die zentralen Fragestellungen des Kapitels definiert werden. Die Kapitel enden jeweils mit einer abschließenden Zusammenfassung inklusive Diskussion. Das erste Kapitel gibt dem Leser allgemeine Informationen über den Hintergrund der Arbeit, während das zweite Kapitel die Motivation für die Arbeit sowie deren Zielsetzung beinhaltet. Eine Gesamtzusammenfassung der Arbeit sowie ein Ausblick für zukünftige Forschungsarbeiten, für die diese Arbeit den Grundstein gelegt hat, finden sich in Kapitel 8. Einige Teile dieser Doktorarbeit wurden bereits in wissenschaftlichen Fachzeitschriften veröffentlicht, befinden sich gerade im Begutachtungsprozess bei einer Fachzeitschrift oder werden in naher Zukunft eingereicht.

Dies wurde zu Beginn jedes Kapitels kenntlich gemacht.

Diese Doktorarbeit wäre in dieser Form nicht möglich gewesen ohne die Unterstützung von zahlreichen Personen, denen ich an dieser Stelle ganz herzlich danken möchte.

An allererster Stelle möchte ich mich bei Helmut Cölfen bedanken für die Aufnahme in seine Arbeitsgruppe, seine hervorragende Betreuung und Unterstützung während der gesamten Promotion sowie die ausgezeichneten Arbeitsbedingungen. Besonders möchte ich ihm für das große Interesse an den verschiedenen Teilprojekten danken sowie für seine Bereitschaft, wissenschaftliche Ergebnisse eingehend zu diskutieren und mich in schwierigen Situationen zu unterstützen.

Stefan Mecking möchte ich für die Übernahme der Zweitbetreuung und des Zweitgutachtens danken sowie für die Bereitstellung seiner Ausstattung, die essentiell für große Teile dieses Projekts war. Des Weiteren danke ich ihm für hilfreiche Diskussionen und zahlreiche konstruktive Vorschläge. Bedanken möchte ich mich auch bei Valentin Wittmann für die Übernahme des Prüfungsvorsitzes.

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iv Ein großer Dank gilt auch Helmut Schlaad, der mich bei den Polymersynthesen und Polymercharakterisierungen unterstützt hat und bei Problemen immer ein offenes Ohr hatte.

Ich möchte mich auch für die Aufenthalte in seinem Labor bedanken, die mir bei meiner Arbeit sehr weitergeholfen haben.

Die mechanischen Untersuchungen und SAXS-Messungen der Kompositmaterialien sowie deren Auswertungen wurden in Kooperation mit Peter Fratzl und Igor Zlotnikov am Max- Planck-Institut für Kolloid- und Grenzflächenforschung (Abteilung Biomaterialien) durchgeführt. An dieser Stelle möchte ich mich herzlich für diese Kooperation bedanken, besonders bei Igor, der sehr viel Arbeit in die Messungen gesteckt hat und mit seinen Interpretationen sowie zahlreichen Diskussionen sehr zum Gelingen dieses Projekts beigetragen hat.

Bedanken möchte ich mich auch bei Paul Zaslansky vom Julius-Wolf-Institut an der Charité in Berlin für Mikrotomographiemessungen und deren Rekonstruktionen sowie für einen Aufenthalt in seinem Labor, währenddessen ich eine Einführung in diese Messtechnik bekommen habe.

An dieser Stelle möchte ich auch Matthias Kellermeier danken, der immer Zeit fand Ergebnisse der Calciumsulfat-Untersuchungen zu besprechen und mit dessen Hilfe ich Kooperationen zum Laboratorio de Estudios Cristalográficos in Granada aufbauen konnte.

Diese Kooperationen bezüglich XRD- und IR-Messungen mit Sander van Driessche bzw.

Raman-Mikroskopiemessungen mit José Manuel Delgado waren wichtig für die vollständige Charakterisierung der hergestellten Materialien.

Während der gesamten Promotion wurde eine große Anzahl verschiedener analytischer Methoden verwendet. Daher gilt mein Dank einer ganzen Reihe von Leuten, die mich hierbei unterstützt haben. Marina Krumova möchte ich für die TEM- und AFM-Einführungen danken sowie für ihre Bereitschaft, technische Probleme der Geräte immer schnellstmöglich zu lösen.

Matthias Hagner danke ich für die SEM-Einführung und für seine Hilfe im Bereich der Mikroindentation und Lithographie. Bei Rose Rosenberg, Dirk Haffke und Antje Völkel möchte ich mich für die AUZ-Messungen bedanken, bei Andreas Marquardt (Genomics Center, Universität Konstanz) für die MALDI-ToF MS Messungen, bei Lars Bolk für die GPC-Messungen, bei Lauretta Nejedli für die Mikrotom-Schnitte (Elektronenmikroskopie- Service, Universität Konstanz), bei Elena Rosseeva für die Hilfe bei der Auswertung von TEM-Ergebnissen, bei Maria Helminger für XRD-Messungen, bei Jens Weber (MPI

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v Messungen. Rainer Winter, Michael Linseis und Stefan Scheerer danke ich für ihre Hilfsbereitschaft bei den CV-Messungen sowie für zahlreiche anregende Diskussionen. Ein großer Dank gilt auch Nora Fiedler (MPI Potsdam), die mich dabei unterstützt hat, die benötigten Polymere in größeren Mengen herzustellen.

Des Weiteren möchte ich mich bei Christian Debus, Philipp Keckeis, Franziska Beck, Markus Voggenreiter, Patrick Herr, Eduard Wiedenbeck und Alexander Kleiber für ihre engagierte Mitarbeit im Zuge ihrer Bachelorarbeiten, Mitarbeiterpraktika bzw. als studentische Hilfskräfte bedanken.

Mein Dank gilt auch der Deutschen Forschungsgemeinschaft (Schwerpunktprogramm 1420) und der BASF für die finanzielle Unterstützung.

Meiner Arbeitsgruppe danke ich für das angenehme Arbeitsklima mit den vielen gemeinsamen Aktivitäten sowie für die Hilfsbereitschaft und die freundliche Laboratmosphäre. Ein Dank gilt an dieser Stelle ganz besonders Matthias, Andi und Denis sowie Maria, Jo und Wolfi, die mir in zahlreichen Diskussionen weitergeholfen haben.

Ein besonderer Dank geht an meine Eltern, die mich immer unterstützt haben und mir diese Promotion überhaupt erst ermöglicht haben. Bedanken möchte ich mich auch bei meiner Freundin Astrid für ihre liebevolle Unterstützung und die schöne Zeit außerhalb des Labors.

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vi

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vii

Publications

Part of this work has been published:

I. Journals

(1) Tritschler, U.; Zlotnikov, I.; Zaslansky, P.; Aichmayer, B.; Fratzl, P.; Schlaad, H.;

Cölfen, H. “Hierarchical Structuring of Liquid Crystal Polymer–Laponite Hybrid Materials”. Langmuir 2013, 29, 11093-11101 (including Cover Page).

(2) Tritschler, U.; Zlotnikov, I.; Zaslansky, P.; Fratzl, P.; Schlaad, H.; Cölfen, H.

“Hierarchically Structured Vanadium Pentoxide–Polymer Hybrid Materials”. ACS Nano 2014, 8, 5089-5104.

(3) Tritschler, U.; Zlotnikov, I.; Keckeis, P.; Schlaad, H.; Cölfen, H. “Optical Properties of Self-Organized Gold Nanorod–Polymer Hybrid Films”. Langmuir 2014, 30, 13781- 13790.

(4) Tritschler, U.; Beck, F.; Schlaad, H.; Cölfen, H. “Electrochromic Properties of Self- Organized Multifunctional V₂O₅–Polymer Hybrid Films“. J. Mater. Chem. C 2015, 3, 950-954 (including Inside Front Cover).

(5) Tritschler, U.; Van Driessche, A. E. S.; Kempter, A.; Kellermeier, M.; Cölfen, H.

“Controlling the Selective Formation of Calcium Sulfate Polymorphs at Room Temperature”. Angew. Chem., Int. Ed. 2015, 54, 4083-4086.

(6) Tritschler, U.; Kellermeier, M.; Debus, C.; Kempter, A.; Cölfen, H. “A Simple Strategy for the Synthesis of Well-Defined Bassanite Nanorods”. CrystEngComm 2015, 17, 3772-3776.

(7) Tritschler, U.; Delgado, J. M.; Kellermeier, M.; Schlaad, H.; Cölfen, H. “Gypsum–

polymer hybrid materials via a bottom-up synthesis”. Manuscript in preparation.

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viii II. Conference Contributions (Talks & Posters)

(1) Tritschler, U.; Dambowsky, I., Zlotnikov, I.; Aichmayer, B.; Schlaad, H.; Cölfen, H.

“Hierarchical Composites by Gluing of Nano- and Mesocrystals”. Winter school within the DFG priority program 1420, Potsdam, Germany, 19-20 March 2012, (Talk

& Poster).

“Polymers for Hierarchically Structured Organic-Inorganic Composite Materials”.

DGM Conference Bio-inspired Materials, Potsdam, Germany, 20-23 March 2012 (Poster).

“Bioinspired Hybrid Materials by Gluing of Anisotropic Nanocrystals”. EMRS 2012 Spring Meeting, Strasbourg, France, 14-18 May 2012 (Poster).

“Bioinspired Hybrid Materials by Gluing of Anisotropic Nanocrystals” (Talk) and

“Bioinspired Hybrid Materials by Gluing of Anisotropic V2O5 Nanoparticles” (Talk).

87^th ACS Colloid and Surface Science Symposium, Riverside, California, USA, 23-26 June 2013.

“Bioinspired Hierarchically Structured Hybrid Materials by Gluing of Anisotropic Nanocrystals”. 126^th BASF International Summer Course 2013, Ludwigshafen, Germany, 20-29 August 2013 (Poster).

“Bioinspired Organic-Inorganic Hybrid Materials by Gluing of Anisotropic Nanoparticles”. DGM-Konferenz „Bio-inspired Materials“, Potsdam, Germany, 18-21 March 2014 (Talk).

“Bioinspired Hierarchically Structured Hybrid Materials”. 10^th Zsigmondy- Colloquium, Konstanz, Germany, 7-8 April 2014 (Poster).

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ix

List of Figures, Tables and Schemes

Figure 1.1: Design of a flying machine by Leonardo da Vinci.¹ ... 1 Figure 1.2: The lotus effect defined as the high water repellence occurring on lotus leaves (a),¹⁰ and its commercial application in the textile industry for water-resistant tissue (b).¹¹ Burdocks¹² (c) and shaddocks¹³ (e) led to the development of hook-and-loop fasteners¹⁴ (d) and motorcycle helmets¹⁵ (e), respectively. ... 2 Figure 1.3: (a) Green brittlestar – Ophiarachna incrassate,²² and (b) Venus flower basket glass sponges.²³ ... 3 Figure 1.4: Scheme of arrangement of mineral platelets in collagen fibrils, which are staggered in their long axis by 67 nm (a). The mineralized collagen fibrils form fiber bundles (b, c), building up a lamellar structure (d).²⁵ ... 4 Figure 1.5: Iridescence of nacre – Neotrigonia margaritacea.³² ... 5 Figure 1.6: Scheme of the brick-and-mortar microstructural arrangement of columnar nacre (a) and sheet nacre (b).³⁵ Top view (c, d) and cross sectional view (e, f) of columnar and sheet nacre, respectively.³⁴ (g) Suggested model for the formation of nacre before mineralization (left) and after mineralization (right), according to Addadi et al.⁴⁰ ... 7 Figure 1.7: Arrangement of mineral particles (dark gray) in organic phase (light gray).

The horizontal white lines indicate shearing forces occurring in the organic phase between the stiff particles. In absence of shear, the white lines are horizontal (a), whereas their orientation changes upon applying deformation forces (b). Tensile stress can only be transmitted through the organic matrix when assuming a tight interface between organic and inorganic components.^24,30 ... 9 Figure 1.8: Toughening mechanisms in bone: viscoplastic flow (a), microcracking (b), crack bridging (c), and crack deflection (d). The shaded areas indicate the stressed domains close to the crack tip.⁵¹ ... 10 Figure 1.9: (a) SEM image of crack bridging in human cortical bone by collagen fibers.⁵² (b) SEM graph of a crack in an osteon, which is deflected by bone lamellae, forming a zigzag path. The horizontal red lines indicate successive lamellae. The inset illustrates the rotating orientation of collagen fibers within lamellaes.^49,51 ... 10 Figure 1.10: Schematic illustration of classical and non-classical crystallization. (a) Classical crystallization pathway, (b) oriented attachment pathway leading to iso- oriented crystals, (c) mesocrystal formation via mesoscale assembly.⁶³ ... 11 Figure 1.11: TEM images of arrangements of prismatic BaCrO4 nanoparticles in chains (left) and a rectangular superlattice of BaCrO₄ nanoparticles (right; 2-dimensional aggregation) prepared in a reverse microemulsion. Right image: The arrow displays dislodged particles, revealing the prismatic morphology of individual particles. The electron diffraction pattern in the inset shows the superimposition of reflections from zone axes approximately parallel to the (110) direction. The scale bar is in both images 50 nm.^62,64 ... 12 Figure 1.12: SEM images of progressive stages of the growth via self-assembly of fluorapatite aggregates in a gelatin gel (morphogenesis): from elongated hexagonal- prismatic seeds (a) through dumbbell shapes (b) to spherical shapes (c). The surface of the spheres shown in (c) is composed of needle-like subunits.^62,65 ... 13

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xvi Figure 1.13: Illustration of some principal concepts for three-dimensional alignments of nanoparticle building units to form a mesocrystal. (a) Alignment of nanoparticles by means of physical fields or mutual alignment of identical crystal faces; (b) epitaxial growth via mineral bridges; (c) nanoparticle alignment by spatial constraints.⁶¹ ... 13 Figure 1.14: (a) SEM image of dumbbell-like aggregation of BaTiO3 nanoparticles in the presence of an external electric field.⁶⁷ (b, c) Superlattices composed of maghemite nanocubes were found to form by slow drying of a concentrated toluene-based maghemite nanocube dispersion. (b) Low-magnification TEM image. Scale bar is 1 µm.

(c) Enlargement of a superlattice and selected area diffraction patterns on atomic scale (inset upper right) and on mesoscale (inset lower left), indicating a high degree of orientational order. Scale bar is 500 nm.⁶⁸ ... 14 Figure 1.15: (a) SEM image of helical BaCO3 nanoparticle superstructure formed after two weeks in the presence of polyethyleneglycol-b-[(2-[4-dihydroxyphosphoryl]-2- oxabutyl)-acrylate ethyl ester]. (b) Scheme of the proposed mechanism for helix formation.⁶⁹ ... 14 Figure 1.16: Arrangement of mesogens in a nematic LC phase (a), a smectic A (b, left) and a smectic C LC phase (b, right), and a chiral nematic LC phase (c). The molecules in the chiral nematic phase are twisted perpendicular to the director, with the molecule axis parallel to the director; p/2 refers to the half-helical pitch (d).⁸¹ ... 17 Figure 1.17: (a) Polarized optical microcopy of a 10 wt% solution of the polymer shown in (b), revealing the formation of a lyotropic chiral nematic LC phase with a characteristic double-spiraled texture characteristic. The inset shows a fingerprint texture of the lyotropic phase with a half-helical pitch of 1.5 µm. (b) Scheme of the aligned polymer chains forming the chiral nematic LC phase.⁸² ... 17 Figure 1.18: Rod-coil copolymer consisting of a mesogenic rod (length of 6 nm) and a monodisperse polyisoprene.⁸⁷ ... 19 Figure 1.19: Scheme of the stacking arrangement of rod-coil copolymer with f_rod = 0.36 (a) and the close-packed hexagonal superlattices of rod-coil copolymer with f_rod = 0.25 (b).⁸⁸ ... 19 Figure 1.20: (A) N,N-di-2-propoxyethyl-N-3-mercaptopropyl-N-methylammonium chloride was used as ligand to obtain moderately hydrophilic platinum nanoparticles with high solubility. (B) Platinum nanoparticle with a core diameter of 1.8 nm and a ligand shell of 1.4 nm. (C) Poly(isoprene-block-dimethylaminoethyl methacrylate) (molecular weight of 28 000 - 31 000 g mol^-1 and polydispersity of 1.04 - 1.05). (D) Self-assembly of platinum nanoparticles with block copolymer, leading to a mesostructured hybrid. (E) Mesoporous Pt-C composite obtained by pyrolysis under inert atmosphere. (F) Ordered mesoporous platinum structure after removal of C via Ar- O plasma treatment or acid etch.⁹¹ ... 20 Figure 1.21: (a) Comparison of a composite cholesteric film made of reactive monomer structures (left) and a Chrysina resplendens beetle (right). (b) SEM image of the composite cholesteric film consisting of different layers: 1) cholesteric, 2) untwisted retarder layer, 3) cholesteric and 4) untwisted alignment layer.⁹³ ... 21 Figure 1.22: (a) Scheme of chiral nematic ordering of nanocrystalline cellulose crystallites, showing the half-helical pitch P/2 (ca. 150-650 nm). (b) POM image of a nanocrystalline cellulose/Si(OEt)4 suspension, acquired during solvent evaporation at room temperature. The fingerprint texture characteristic indicates a chiral nematic ordering. (c) POM image of a nanocrystalline cellulose/silicate composite film, revealing

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xvii regions with different orientations. (d) POM image of a mesoporous silica film, which was obtained by calcination of the nanocrystalline cellulose/silicate composite film shown in (c). (b–d) Scale bar, 100 µm.¹⁰² ... 22 Figure 1.23: Optical characterization of mesoporous silica films, which were obtained by calcination of nanocrystalline cellulose/silicate composite films. The ratio of silica:nanocrystalline cellulose was increased from S1 to S4. (a) The transmission spectra of the mesoporous silica films reveal a blue-shift of the reflectance peaks of

~300 nm, leading to films that reflect light across the whole visible spectrum. (b) Photographs of the mesoporous silica films S1 to S4. The colors result only from the chiral nematic pore structure of the films. The coin (diameter of 1.8 cm) represents the scale bar.¹⁰² ... 23 Figure 1.24: SEM image of a calcite mesocrystal, obtained by gas diffusion technique in presence of polystyrene sulfonate.¹⁰³ ... 24 Figure 1.25: (A) Mechanism for the formation of hierarchical self-similar calcite mesocrystals, built from triangular calcite building blocks. Nearly spherical CaCO3

nanoparticles formed in the early reaction stage (a), which then crystallized and aggregated in the presence of poly(styrene-alt-maleic acid) (exposed faces are (001) and (011); b)). Further aggregation, finally forming aggregates with the shape of their subunits, probably along the (011) faces (c). 3D mesocrystal composed of triangular calcite building units formed by mesoscale assembly (d). (B) SEM image of the calcite mesocrystal formed in presence of poly(styrene-alt-maleic acid). The inset illustrates the Sierpinski triangle.¹⁰⁵ ... 24 Figure 3.1: TEM images of coagulate particles synthesized from poly(2-isopropyl-2- oxazoline) in pure water (a) and in a water/ethylene glycol mixture of 95:5 v/v (b). Scale bar is 2 µm in both images.^118,119... 32 Figure 3.2: Evaporation-induced micellation of amphiphilic poly(2-oxazoline) copolymers performed by spin-coating (left). Representative scanning force microscopy image revealing the formation of an array of micelles on the surface (right; 0.5 µm × 0.5 µm).^107,125... 32 Figure 3.3: ¹H NMR spectrum (400 MHz, CDCl3) of the LC ‘gluing’ copolymer P4, modified with Chol-SH and Boc-Cys. ... 35 Figure 3.4: Penetration scan of LC ‘gluing’ copolymer P4 (a/b/c = 0.51/0.21/0.28), acquired by POM at 50x magnification. ... 37 Figure 3.5: Quantitative birefringence optical micrograph (Abrio) image of shear- induced lyotropic phase formation of LC ‘gluing’ copolymer P4 (a/b/c = 0.51/0.21/0.28).

(a) 50+ wt% in CHCl3; (b) and (c) 50+ wt% in DMF. ... 38 Figure 3.6: Cryo-TEM images of aqueous dispersion of PBOx-Chol-MPNa ([C=C]/[Chol-SH]/[MPNa] = 0.50/0.21/0.33) under physiological conditions (polymer concentration: 10 mg mL^-1). ... 39 Figure 4.1: (a) Single Laponite crystal. (b) Idealized structural formula: 6 octahedral magnesium ions are situated between two layers consisting each of 4 tetrahedral silicon atoms. The unit cell is completed by 20 oxygen atoms and 4 hydroxyl groups.¹³⁷ ... 45 Figure 4.2: Thermogravimetric analysis of Laponite, polymer reference and Laponite/polymer hybrid particles obtained after initiating the hybrid synthesis at a pH of 6 (measurements under O2 atmosphere). ... 49

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xviii Figure 4.3: Quantitative birefringence optical micrographs (Abrio). Laponite/PBOx- Chol-DEA composite materials with Laponite:polymer = 1:1 (a) and 2:1 w/w (b).

Composites were sheared by rotation and dried at room temperature before taking the images. ... 50 Figure 4.4: SEM images of dried Laponite/PBOx-Chol-DEA 1:1 w/w (a) and 2:1 w/w (b) composites obtained after shearing by rotation. Images of the cross section (fracture surface) of the composite reveal a layered structure on the length scale of ~50-100 nm.

Cross sections without pronounced layered structuring were also observed (c, example SEM image of a Laponite/polymer 2:1 w/w composite). ... 51 Figure 4.5: Representative SAXS 2D patterns from dried Laponite/PBOx-Chol-DEA 1:1 w/w composites prepared by rotational shearing, which were obtained with the incident beam perpendicular (a) and parallel (b) to the shearing direction. The expected platelet orientation of the composites is illustrated in (c). ... 51 Figure 4.6: Thermogravimetric analysis of Laponite, polymer reference and Laponite/polymer hybrid particles obtained after initiating the hybrid synthesis at a pH of 9 (measurements under O2 atmosphere). ... 53 Figure 4.7: Quantitative birefringence optical micrographs (Abrio) of dried Laponite/PBOx-Chol-DEA composites with Laponite:polymer = 1:1 (a) and 2:1 w/w (b). The synthesis was initiated using a Laponite dispersion with a pH of 9. The hybrid materials were sheared by rotation. ... 54 Figure 4.8: SEM images of the cross section (fracture surface) of dried Laponite/PBOx- Chol-DEA 1:1 (a) and 2:1 w/w (b) composites obtained after shearing by rotation. The hybrid synthesis was initiated using a Laponite dispersion with a pH of 9. The cross sections of the composites exhibit a layered structuring on the length scale of ~50-100 nm. ... 54 Figure 4.9: Representative SAXS 2D patterns from dried Laponite/PBOx-Chol-DEA 1:1 w/w composites prepared by rotational shearing, which were obtained with the incident beam perpendicular (a) and parallel (b) to the shearing direction. Hybrid synthesis was initiated using a Laponite dispersion with a pH of 9. ... 55 Figure 4.10: Representative SAXS plots of Laponite reference and Laponite/PBOx- Chol-DEA 1:1 and 2:1 w/w composites. Solid and dashed lines represent integrated data obtained parallel and perpendicular to the rotational direction, respectively... 56 Figure 4.11: AUC sedimentation coefficient distributions ls-g*(s) of polymer P4 (black), Laponite (red), Laponite/P4 1:1 w/w (green), and 2:1 w/w (blue) as obtained from sedimentation velocity experiments at (a) 20K rpm and (b) 60K rpm at 25°C, indicating binding between Laponite and P4. ... 59 Figure 4.12: Quantitative birefringence optical micrographs (Abrio). Laponite/P4 composite materials with Laponite:P4 = 1:1 w/w (upper row) and 2:1 (lower row).

Composites were sheared by rotation (left column) or by lateral shearing (right column) and investigated in the dry state. ... 61 Figure 4.13: Phase-contrast-enhanced monochromatic (10 KeV) radiograph (a) (gray level intensities correspond to the extent of transmission where 1.00 corresponds to complete transmission and values higher than 1.00 are due to interference fringes localizing at interfaces) and a tomographic reconstruction slice (b) of a dried composite sample consisting of Laponite/P4 1:1 w/w, obtained after shearing by rotation. ... 62

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xix Figure 4.14: SEM images of a dried Laponite/P4 2:1 w/w composite obtained after shearing by rotation. Images of the cross section (fracture surface) of the composite reveal the layer structure on the length scale of ~50 nm, which is illustrated by increasing the magnification from left to right. ... 62 Figure 4.15: Representative SAXS 2D patterns from dried Laponite/P4 1:1 w/w composites prepared by rotation, obtained with the incident beam perpendicular (a) and parallel (b) to the shearing direction... 63 Figure 4.16: Representative SAXS plots of Laponite reference and Laponite/P4 1:1 w/w and 2:1 w/w composites prepared by rotation. Solid and dashed lines represent integrated data obtained parallel and perpendicular to the rotational direction, respectively. Insert: Kratky SAXS plot of the same data. ... 63 Figure 4.17: TEM image (a) and corresponding electron diffraction (b, ED pattern assigned according to Neumann et al.¹⁶⁵) of a cross section of the composite material Laponite/P4 2:1 w/w prepared via shearing by rotation. The inset of the TEM image shows columnar structuring of Laponite nanoparticles as observed via SAXS (see inset scheme in Figure 4.16). ... 64 Figure 4.18: Quantitative birefringence optical micrographs (Abrio). Cross-linked Laponite/PBOx-Chol-MPA composite materials with Laponite:LC polymer = 1:1 w/w (left) and 2:1 (right). Composites were sheared by rotation, followed by crosslinking under UV irradiation until being dried. ... 71 Figure 4.19: SEM images of cross-linked Laponite/PBOx-Chol-MPA 2:1 w/w composite obtained after shearing, followed by cross-linking with UV light until being dried. Images of the cross section (fracture surface) of the composite reveal a layered structuring on the length scale of ~50 nm (magnification increases from left to right). ... 71 Figure 4.20: Representative SAXS 2D patterns from cross-linked Laponite/LC polymer 2:1 w/w composites, obtained with the incident beam perpendicular (a) and parallel (b) to the shearing direction. ... 71 Figure 4.21: Representative SAXS plots of Laponite reference and cross-linked Laponite/PBOx-Chol-MPA 1:1 and 2:1 w/w composites. Solid and dashed lines represent integrated data obtained parallel and perpendicular to the shearing direction, respectively. The SAXS measurement was performed by using a distance between detector and sample of 260 mm (main graph) and 1050 mm (graph lower right). Graph upper right: Kratky SAXS plot of the same data. ... 72 Figure 5.1: (a) Schematic illustration of an electrochromic device. Arrows indicate the movement of positive ions by means of an electric field.²⁴¹ (b) Assembly of an electrochromic cell, sandwiching a mesostructured V2O5 film.²⁰¹ ... 87 Figure 5.2: Quantitative birefringence optical micrograph (Abrio) images of V2O5LC

‘gluing’ statistical copolymer (PBOx-Chol-MPNa) composite materials starting from V₂O₅ tactoid (left column) or from isotropic V₂O₅ tactosol (right column). (a-d) Preparation of composites via phase transfer involving freeze-drying, followed by swelling in THF. Longitudinal cuts (thickness 1 µm) parallel to the shearing direction from composites FD-TACT (a) and FD-ISO (b); cross sectional cuts (thickness 1 µm) perpendicular to the shearing direction of composites FD-TACT (c) and FD-ISO (d). (e- h) Preparation of composites via phase-transfer by centrifugation. Longitudinal cuts (thickness 1 µm) parallel to the shearing direction of composites CEN-TACT (e) and CEN-ISO (f); cross sectional cuts (thickness 0.5 µm) perpendicular to the shearing direction of composites CEN-TACT (g) and CEN-ISO (h). ... 94

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xx Figure 5.3: (a) Phase-contrast-enhanced monochromatic cross sectional radiograph and (b) a typical tomographic reconstruction slice of a longitudinal section and cross section (inset bottom right) of composite sample CEN-TACT. The inset diagram (top right) gray-level intensity vs. distance reveals a regular texturing of ca. 5–6 µm over areas of 100 × 100 µm² in the longitudinal slice (the inset diagram plots intensity variations along the marked red line area). ... 95 Figure 5.4: SEM analysis of cross section (a) and longitudinal sections (b, c) of V₂O₅ composite materials for which phase transfer was performed via freeze-drying and subsequent swelling in THF. ... 96 Figure 5.5: SEM analysis of the cross section (a and b) and longitudinal section (c) of V₂O₅ composite materials for which phase transfer was performed via centrifugation. ... 97 Figure 5.6: Representative SAXS data obtained from V₂O₅LC ‘gluing’ copolymer composites. (a–d) Patterns obtained with the incident beam perpendicular to the layered structure. (e–h) Patterns obtained with the incident beam parallel to the layered structure:

composite FD-TACT (patterns a and e), CEN-TACT (patterns b and f), FD-ISO (patterns c and g), and CEN-ISO (patterns d and h). (i–l): SAXS plots obtained by radial integration in the horizontal and vertical segments on 2D SAXS patterns obtained with the incident beam parallel to the layered structure. ... 98 Figure 5.7: TEM images of composite materials obtained from LC ‘gluing’ copolymer and isotropic V2O5 tactosol (FD-ISO; (a) cross section and (b) longitudinal section) or V2O5 tactoid (FD-TACT; (c) cross section and (d) longitudinal section). Phase transfer from aqueous medium to THF was performed via freeze-drying and swelling in THF, followed by rotational shearing of the samples. Cross sectional cuts of the composites exhibit a thickness of 85 nm and longitudinal cuts, a thickness of 95 nm. ... 100 Figure 5.8: TEM images of composite materials obtained from LC ‘gluing’ copolymer and isotropic V₂O₅tactosol (CEN-ISO; (a) cross section and (b) longitudinal section) or V2O5 tactoid (CEN-TACT; (c) cross section and (d) longitudinal section). Phase transfer from aqueous medium to THF was performed via centrifugation and, subsequently, samples were rotationally sheared. Cross sectional cuts of the composites exhibit a thickness of 85 nm and longitudinal cuts, a thickness of 95 nm. ... 101 Figure 5.9: SEM image of a bending experiment of an as-prepared V2O5–LC polymer composite. The manipulator (steel needle) was used to apply load on the composite, leading to bending of the material. ... 104 Figure 5.10: Optical transmittance spectra of V2O5–LC polymer hybrid films in the oxidized state (black) and reduced state (red) under alternating potentials of -0.5 V and 1.5 V (sweep rate of 50 mV s^-1), and example images of hybrid films in the oxidized and reduced state. Change in transmittance was observed at a wavelength of 450 nm (dotted line). The artefact at ca. 650 nm is caused by the spectrometer. ... 105 Figure 5.11: Cycling stability of V₂O₅–LC polymer hybrid films was investigated by applying alternating potentials (-0.5V–1.5 V; sweep rate of 50 mV/s). The change in transmittance was recorded at a wavelength of 450 nm. After equilibration, the decrease in transmittance over more than 100 cycles was less than 20%. ... 106 Figure 5.12: Long-term stability of a V2O5–LC polymer hybrid film with a minimum transmittance of ca. 0.7. After over 100 switching cycles between -0.5V and 1.5 V with a sweep rate of 50 mV s^-1 (black curve: switching cycles 91-96), the electrochromic device was stored for more than 1 month. Application of alternating potentials (-0.5V–1.5 V;

sweep rate of 50 mV s^-1) after storing reveals a similar cycling behaviour showing only a

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xxi negligible decrease in transmittance change (red curve). Transmittance values were taken at 450 nm. ... 107 Figure 5.13: Example cyclic voltammogram of V2O5–LC polymer hybrid films, which was recorded in 1 M Lithium bis(trifluoromethylsulfonyl) imide in propylene carbonate with a sweep rate of 50 mV s^-1. ... 108 Figure 5.14: Charge density of reduction steps (black quadratic symbols) and oxidation steps (black circle symbols) and corresponding charge reversibility (defined as ratio of the charge density of an oxidation step to the charge density of the previous reduction step; red) of V2O5–LC polymer hybrid films obtained during repetitive voltammetric cycling between -0.5 V and 1.5 V with a sweep rate of 50 mV s^-1. Data of every fifth switching cycle out of 100 cycles are illustrated. ... 109 Figure 5.15: Quantitative birefringence optical (Abrio) micrographs (a, b) and SEM images (c-f) of V2O5–LC polymer hybrid films before and after voltammetric cycling (left and right columns, respectively). ... 110 Figure 6.1: Stained-glass pane in the cathedral Notre-Dame (Paris, France).²⁸⁵ ... 119 Figure 6.2: (a) Interaction of an incident electromagnetic radiation with a spherical gold nanoparticle, leading to the formation of a dipole, which oscillates in-phase with the electric field of the incident light. (b) Transversal and longitudinal oscillations of conduction electrons in a gold nanorod.²⁸⁶ ... 120 Figure 6.3: Optical properties of gold nanorods embedded in a poly(2-vinyl pyridine) film were correlated with their local orientation, forming side-by-side assemblies and percolated networks with end-to-end and side-by-side linkages. For example, end-to-end and side-by-side alignments of gold nanorods induce red-shifts and blue-shifts of the LSPR, respectively (see arrows).²⁹⁹ ... 122 Figure 6.4: Thermogravimetric analysis of GNR–LC polymer hybrid materials and of gold nanorod and polymer reference (measurements under O2 atmosphere). ... 124 Figure 6.5: AUC sedimentation coefficient distribution ls-g*(s) of CTAB-coated gold nanorods (black) and GNRLC polymer hybrid particles with initial ratio of 1:1 w/w (red) in aqueous dispersion (a) and after phase-transfer to DMF (c), obtained from sedimentation velocity experiments. Corresponding UV-visible spectra of CTAB-coated gold nanorods (black) and hybrid particles (red) in aqueous dispersion (b) and after phase-transfer to DMF (d). ... 125 Figure 6.6: Polarized optical micrograph image in reflective mode (a) and quantitative birefringence optical micrograph image (b) of a GNRpolymer composite film with a ratio of GNR to organics of 5:1 w/w prepared by spin-coating. ... 129 Figure 6.7: SEM analysis of GNRLC polymer composite films with a ratio of GNR to organics of 5:1 w/w by using different magnifications (a and b) as well as an AFM height image (c) and the corresponding phase image (d) of the GNRLC polymer composite film. ... 129 Figure 6.8: Analysis of a representative SAXS plot (black circles) of GNRLC polymer composite films with the incident beam perpendicular to the shearing direction. (Inset) 2D SAXS pattern of the same data. The fitting to a theoretical model of the structure (red line) was performed using Scatter 2.5 software.³⁰⁸ ... 130 Figure 6.9: TEM images of spin-coated GNRpolymer composite films, consisting of a ratio of GNRs to polymer of 5:1 w/w. Due to the high gold particle fraction, structural

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xxii orientation of the composite film via TEM analysis was only partially accessible, i.e. for domains exhibiting one to two gold particle layers (mainly in marginal domains).

Consequently, TEM images do not reflect quantitative information on nanoparticle packing and alignment. ... 131 Figure 6.10: UV-visible spectra of GNRpolymer hybrid dispersion in DMF (black) and GNRpolymer composite film (red). ... 132 Figure 7.1: Characterization of solid products obtained by quenching 25 mM CaSO4

solution into an excess of ethanol, giving dispersions with final water contents ranging from 16 to 27 wt%. (a) IR spectrum of the precipitates, showing typical bands of bassanite (the dashed line marks the position of a characteristic peak appearing only in presence of gypsum). (b) XRD pattern of the product, wherein reflections belonging to bassanite are highlighted with red asterisks and dashed lines indicate the most intense peaks expected for gypsum. (c) TEM image of the precipitates, revealing uniform rod- like nanoparticles that occasionally exhibit pronounced porosity (inset). (d) Corresponding electron diffraction pattern, displaying reflections that can all be indexed to bassanite. (e-f) SEM images of the bassanite particles at different magnifications.

Note that these data represent the fraction of precipitate that remained dispersed in solution. ... 144 Figure 7.2: Bassanite content of precipitates formed upon addition of aqueous calcium sulfate solutions (with variable concentrations) into ethanol/water mixtures at different final water contents. Products were isolated from the resulting dispersions by centrifugation and subsequent drying in vacuum at room temperature. Bassanite yields were obtained by IR analyses as depicted in Figure 7.3. ... 146 Figure 7.3: (a) IR spectra of samples containing bassanite and gypsum in varying defined mass ratios (obtained by mixing the two polymorphs in dry state and homogenizing the conglomerate by careful grinding in a mortar). The red arrow marks the peak at 1684 cm^-1, which only occurs for gypsum. (b) Plot of the intensity of the band at 1684 cm^-1 (in units of transmission) as a function of the bassanite content (wBassanite) in the mixtures. Squares represent experimental data, while the full line is an exponential fit giving the following “calibration” equation: w_Bassanite = 46.3∙ln[(1- T1684)/0.16]. ... 146 Figure 7.4: The graph illustrates the trend (dashed red line) observed for the correlation between the bassanite fraction (wt%) of the product and the dielectric constant of the solvent. Note, the higher water content in the final isopropanol/water and acetone/water reaction mixtures compared to the other reaction mixtures (see Figure S46) was neglected. ... 149 Figure 7.5: Bassanite stability in dispersion: IR patterns of samples drawn after different ageing times from ethanolic dispersions prepared by adding 50 mL of (a) 50 mM and (b) 150 mM CaSO4(aq) solution to 500 mL ethanol (final water content: 16 wt%). During ageing, the dispersions were stirred continuously and formed particles were isolated at the respective time by centrifugation and drying the resulting sediment in vacuum at room temperature. Note that bassanite was stable for at least 28 days at the lower CaSO4

concentration (absence of the band at 1684 cm^-1), whereas significant amounts of gypsum (ca. 25%) were present after 8 days at the higher concentration. With time, transformation of bassanite proceeded gradually at 150 mM CaSO4, and about 85% of gypsum were detected after 28 days. ... 150 Figure 7.6: Transformation of bassanite nanoparticles into stable, micron-sized gypsum crystals. (a) Fraction of bassanite detected by IR as a function of ageing time in an

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xxiii ethanolic dispersion with a water content of 33 wt% (obtained by addition of 50 mL 50 mM CaSO4 solution to 500 mL ethanol). Note that the dispersion was stirred vigorously during the entire experiment. (b-d) TEM images showing the supposedly crucial step in the transformation process, i.e. oriented attachment of bassanite nanorods leading to crystallographically aligned particle assemblies that later merge to yield crystalline gypsum. ... 151 Figure 7.7: Transformation of bassanite into gypsum was followed by in-situ IR experiments. An increase in absorbance at distinct wavenumbers of 1680 cm^-1 and 1620 cm^-1 (a) as well as 1134 cm^-1 (b) suggests the formation of gypsum. ... 152 Figure 7.8: Calcium sulfate particles produced upon addition of concentrated sulfuric acid to an excess of ethanol containing dissolved calcium chloride (H₂SO₄ and CaCl₂ combined in equimolar amounts; final water content: ca. 0.2 wt%; Ca:H2O = 1:5.7). (a- b) TEM images of the precipitates, showing extended networks of fibers as main morphology, with typical widths of ca. 40-50 nm and lengths of several microns per fiber. (c) Corresponding ED pattern, verifying the presence of bassanite. ... 153 Figure 7.9: TEM micrographs (left) and ED patterns (right) of particles formed after addition of concentrated H₂SO₄ to CaCl₂ solutions in (a-b) dry methanol (containing about 0.07 wt% H2O, CaSO4:H2O molar ratio of 1:0.16) and (c-d) methanol with a total water content of 4.14 wt% (CaSO4:H2O = 1:10). Precipitation in pure methanol yields aggregates of spherical nanoparticles (a), which consist of pure anhydrite (b). In the presence of more water, rod-shaped particles are obtained (c), which were confirmed to be bassanite (d). ... 154 Figure 7.10: Infrared spectra of (a) pure anhydrite, formed by precipitation from methanolic solutions at a water content of 0.07 wt% (CaSO₄:H₂O ratio of 1:0.16), and (b) anhydrite, bassanite and anhydrite-bassanite mixtures obtained in the presence of increasing amounts of water, namely (from top to bottom, corresponding CaSO4:H2O ratios in brackets) 0.07 (1:0.16, pure anhydrite, A), 0.54 (1:1.25), 0.60 (1:1.4), 1.49 (1:3.5), and 3.14 wt% (1:7.5, pure bassanite, B). Relative percentages of the two polymorphs, as determined by calibration with a series of defined anhydrite-bassanite mixtures (cf. Figure 7.12) are indicated. ... 155 Figure 7.11: X-ray diffraction patterns of calcium sulfate powders obtained by precipitation from methanolic solutions at final water contents (corresponding CaSO4:H2O ratios in brackets) of (a) 0.07 (1:0.16), (b) 0.43 (1:1), (c) 0.54 (1:1.25), (d) 0.86 (1:2), and (e) 4.14 wt% (1:10). Reflections in (a) and (e) can be assigned to pure anhydrite and bassanite, respectively, whereas (b)-(d) are mixtures of the two polymorphs with compositions as indicated (values derived from IR data). The vertical lines at the top and bottom of graph represent peak positions theoretically expected for anhydrite and bassanite, respectively. The observed broadening of peaks with increasing anhydrite content suggests that corresponding particles exhibit lower degrees of crystallinity than their bassanite counterparts. ... 156 Figure 7.12: “Calibration curve” used to derive the polymorphic composition of anhydrite/bassanite mixtures from IR data. The plot shows the change in the ratio of the intensities of the IR bands at 673 cm^-1 (characteristic of anhydrite) and 659 cm^-1 (typical for bassanite) with increasing anhydrite content in samples that were prepared by mixing known amounts of the two polymorphs. It is evident that there is a linear correlation between the parameters (Abs673/Abs659 = 0.0328 ∙ wt% anhydrite), so that peak intensity ratios of unknown mixtures can be translated into polymorphic fractions. ... 157

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xxiv Figure 7.13: Plot of the bassanite content (weight fraction relative to anhydrite) of precipitates formed in the presence of different total amounts of water, given as mmol H2O per 50 mL of methanol (top axis) and wt% H2O (bottom axis). Values were derived from IR spectra using a calibration procedure, as illustrated by Figure 7.12. The full line represents a dose-response fit meant to describe the sigmoidal behavior of the data. ... 158 Figure 7.14: Left: TGA of bassanite (black) and bassanite–LC polymer hybrid particles synthesized by quenching supersaturated CaSO_4(aq)in DMF containing 0.2 mg mL^-1 (red), 0.5 mg mL^-1 (green) and 1 mg mL^-1 (blue) LC polymer PBOx-Chol-MPA. Solvent exchange of hybrid particles from DMF into THF and toluene led to hybrid materials with decreased polymer fractions (measurements under O₂ atmosphere). Right: SEM image of bassanite–LC polymer 4:1 w/w hybrid particles. ... 164 Figure 7.15: Quantitative birefringence optical micrograph (Abrio) image of bassanite–

PBOx-Chol-MPA composite obtained by rotational shearing (670° per min) without distance holder. ... 166 Figure 7.16: SEM images (top view) of bassanite–LC polymer composites after rotational shearing. ... 166 Figure 7.17: IR spectra of a gypsum-LC polymer composite formed upon transformation of corresponding bassanite aggregates in humid air (red) and neat PBOx- Chol-MPA polymer as a reference (black). Insets: enlarged regions of the gypsum- polymer composite spectrum covering intervals of 1500-2000 and 550-750 cm^-1, confirming the presence of pure gypsum. The composite sample was stored for > 20 h in a closed desiccator under increased humidity at room temperature. ... 167 Figure 7.18: Abrio images of gypsum–LC polymer composite obtained after aging a bassanite–LC polymer composite film (see Figure 7.15) under increased humidity. ... 168 Figure 7.19: SEM images of gypsum–LC polymer composites viewed from the top (left) and in cross-section (right). ... 168 Figure 7.20: Close-up SEM views of the microstructure of gypsum–LC polymer, revealing orientational order of crystal units on the multi-micron scale. ... 169 Figure 7.21: (a) Optical micrograph of a gypsum/polymer hybrid particle. The rectangle marks the region that was mapped by Raman microcopy. (b) Raman XY map visualizing the distribution of polymer- and gypsum-rich regions in a horizontal slice through the structure shown in (a). Different colors represent the magnitude of the ratio of the intensities of the gypsum water band (at 3409 cm^-1) and the polymer peak between 2800 and 3000 cm^-1 (typical spectra are shown in the bottom panel at the respective positions c and d in image b). The sequence yellow-red-green-blue-black indicates increasing amounts of gypsum and decreasing amounts of polymer. ... 170

Figure S1: (a) Scheme of the setup of an AUC sedimentation experiment (image adapted from literature³⁷⁶). (b) Illustration of the different forces acting on a dispersed particle during its sedimentation when applying a gravitational field in the ultracentrifuge.³⁰⁰ ... 201 Figure S2: Light path in an optical microscope (F: focal plane, O: object, Ob: objective;

Oc: ocular/eyepiece).³⁷⁸ ... 205

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xxv Figure S3: (a) Illustration of the polarization of light and the arrangement of crossed polarizers.³⁸⁵ (b) Scheme of a polarized optical microscope setup with a birefringent crystal placed between the crossed polarizers.³⁸⁵ ... 206 Figure S4: Comparison of the optical paths in a light microscope and a transmission electron microscope.³⁷⁹ ... 208 Figure S5: Principle of atomic force microscopy (AFM).³⁹⁵ ... 210 Figure S6: Scattering of the incident beam at crystal lattice planes with distance d.

Constructive interference of the scattered waves only takes place in case the path difference 2d sinθ corresponds to a whole multiple of the wavelength λ of the radiation (Bragg equation). ... 212 Figure S7: Small-angle scattering of X-rays at spherical particles of different size.

Waves that are generated at different position (P1, P2) of the same particle can interfere.³⁷⁹ ... 213 Figure S8: (a) Measured frequency spectrum and (b) calculated autocorrelation function.³⁷⁹ ... 215 Figure S9: Charged particle dispersed in a medium. Illustration of the potential difference as function of the distance from the particle.⁴⁰⁸ ... 217 Figure S10: Principle of the microelectrophoresis of charged colloidal particles (adapted from literature³⁷⁹). ... 217 Figure S11: Electromagnetic spectrum.⁴¹² ... 219 Figure S12: Principle of MALDI ToF MS.⁴¹⁹ ... 223 Figure S13: (a) A Berkovich tip.⁴²⁵ (b) Representative load-displacement curve obtained from an indentation experiment, with the peak indentation load Pmax, the indenter displacement at peak load h_max, the final depth of the contact impression after the unloading procedure hf, and the initial unloading stiffness S.¹⁷³... 225 Figure S14: Example MALDI-ToF mass spectrum of the poly[2-(3-butenyl)-2- oxazoline] precursor (number-average molecular weight ca. 7200 g/mol)... 227 Figure S15: ¹H NMR spectrum (400 MHz, CDCl₃) of poly[2-(3-butenyl)-2-oxazoline]

modified with 1-thiocholesterol and 3-mercaptopropionic acid. ... 227 Figure S16: ¹H NMR spectrum (400 MHz, CDCl3) of poly[2-(3-butenyl)-2-oxazoline]

modified with 1-thiocholesterol and 2-diethylaminoethanethiol. ... 228 Figure S17: Quantitative birefringence optical micrograph (Abrio) images of shear- induced lyotropic phase formation of LC ‘gluing’ copolymer PBOx-Chol-MPA (M_n(MALDI) = 7 200 g mol^-1; [C=C]/[Chol]/[MPA] = 0.50/0.21/0.33) (¹H NMR)) in 50+ wt% in THF (a and b) and PBOx-Chol-DEA (Mn(MALDI) = 7 300 g mol^-1; [C=C]/[Chol]/[DEA] = 0.46:0.17:0.31 (¹H NMR)) in 50+ wt% in DMF (c and d). ... 228 Figure S18: Quantitative birefringence optical micrograph (Abrio) image of a 30+ wt%

solution of LC ‘gluing’ polymer PBOx-Chol-MPA (M_n(MALDI) = 7 300 g mol^-1; [C=C]/[Chol]/[MPA] = 0.47/0.21/0.31) in DMF after shearing by spin-coating (rotation speed of 2000 rpm). ... 229 Figure S19: Quantitative birefringence optical micrograph (Abrio) images of shear- induced lyotropic phase formation of LC ‘gluing’ copolymer PBOx-Chol-MPA (Mn(MALDI) = 9 500 g mol^-1; [C=C]/[Chol]/[COOH] = 0.85:0.05:0.10 (¹H NMR)) in 50+ wt% in DMF. ... 229

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xxvi Figure S20: Quantitative birefringence optical micrograph (Abrio) image of LC phase of LC ‘gluing’ copolymer P4 ([C=C]/[Chol]/[COOH] = 0.51/0.21/0.28). Shearing was induced by means of a strong magnetic field (20+ wt% polymer solution in CHCl3 was exposed to a magnetic field of 6.4 T until being dried). ... 229 Figure S21: Representative SAXS 2D patterns from dried Laponite/PBOx-Chol-DEA 2:1 w/w composite prepared by rotational shearing, which was obtained with the incident beam parallel to the shearing direction. The isotropic pattern suggests that Laponite platelets are not preferred oriented as shown in the scheme. The hybrid synthesis was initiated using a Laponite dispersion with a pH of 6. ... 230 Figure S22: Contour profile of a sheared Laponite-LC polymer composite film consisting of Laponite and LC polymer P4 of 2:1 w/w. The glass slide, on which the composite is fixed, is the reference (height of zero). The difference in height on the composite surface is roughly in the range of 40 µm, deriving from drying the composite material. ... 230 Figure S23: Quantitative birefringence optical micrographs (Abrio) of dried Laponite/P4 = 2:1 w/w composites. Rotational shearing was performed by applying a constant rotational speed of 330° per min clockwise (a) or 1390° per min clockwise (b and c) and by using a distance holder of 0.5 mm (usually a rotational shear speed of 680°

per min clockwise was applied, see Experimental Section 4.6). ... 231 Figure S24: Quantitative birefringence optical micrograph (Abrio) images of dried Laponite/P4 = 1:1 (left) and 2:1 (right) w/w composites. Shearing was induced by means of a strong magnetic field (5.9 T; exposed to magnetic field until being dried). ... 231 Figure S25: Quantitative birefringence optical micrographs (Abrio) of dried Laponite/P4 = 10:1 w/w composites sheared by rotation. ... 231 Figure S26: SEM images of a dried Laponite/P4 10:1 w/w composite obtained after shearing by rotation. The images of the cross section (fracture surface) of the composite reveal a layered structuring on the length scale of ~50 nm, (magnification increases from left to right). ... 232 Figure S27: Representative SAXS plots of Laponite reference and Laponite/P4 10:1 composite. Solid and dashed lines represent integrated data obtained parallel and perpendicular to the shearing direction, respectively. The SAXS measurement was performed by using a distance between detector and sample of 260 mm (main graph) and 1050 mm (graph lower right). Graph upper right: Kratky SAXS plot of the data obtained with distance between detector and sample of 260 mm. ... 232 Figure S28: Quantitative birefringence optical micrograph (Abrio) of a dried cross- linked PBOx-Chol-MPA (functionalization of double bonds with Chol-SH (5%) and MPA (10%)) film, obtained after lateral shearing of the polymer solution in one direction and subsequent cross-linking via UV irradiation for 24 h during drying. ... 233 Figure S29: SEM images of cross-linked Laponite/PBOx-Chol-MPA 1:1 w/w composite obtained after shearing, followed by cross-linking under UV irradiation until dryness. Images of the cross section (fracture surface) of the composite reveal a layered structuring on the length scale of ~50 nm. ... 233 Figure S30: TEM image showing the vanadium pentoxide V2O5 taken from tactosol. ... 234 Figure S31: Thermogravimetric analysis of different vanadium pentoxide hybrid materials and of vanadium pentoxide and polymer reference (measurements under N2

atmosphere). ... 234

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xxvii Figure S32: AUC sedimentation coefficient distribution of V₂O₅ dispersion (4.6K rpm, absorbance optics). The non-diffusion-corrected distribution of the sediment ls g*(s) (y axis) illustrates an apparent measure of the concentration of the absorbing species, and the sedimentation coefficients s (in units of S (Svedberg) = 10^-13 seconds, x axis) are proportional to the size and density of the sedimenting particles. ... 235 Figure S33: (a) SEM image of V2O5–LC polymer composite CENT-ISO. The range of 21 µm × 16 µm was used for elemental mapping. (b) Elemental mapping of sulfur, which is only present in the polymer. (c) Elemental mapping of vanadium, which is only present in the inorganic phase (V2O5). Bright coloration indicates presence of the respective element. The homogenous pattern of (a) and (b) suggests homogenous distribution of the elements and consequently, homogenous distribution of organic and inorganic components. ... 235 Figure S34: FFT analysis on cross sections of V2O5 composite CEN-ISO (a) and CEN- TACT (b) (thickness of cuts 85 nm). Superstructure reflections reveal a packing of ribbons of ca. 5-6 nm. ... 236 Figure S35: Electron diffraction on V2O5 composite materials CEN-ISO (cross section (a) and longitudinal section (b)) and CEN-TACT (cross section (c) and longitudinal section (d)). Electron diffractions were taken from domains illustrated in Figure 5.8.

Phase-transfer from aqueous medium to THF was performed via centrifugation, and subsequently, samples were rotationally sheared. Cross sectional cuts of the composites exhibit a thickness of 85 nm and longitudinal cuts a thickness of 95 nm. Only ED of cross sections reveals spots corresponding to a distance of ca. 8.3 Å. ... 236 Figure S36: V2O5–LC polymer composite. Beams for mechanical bending experiments were prepared by using ion-beam lithography; (a) top view; (b) front view. ... 237 Figure S37: Contour plot of a section of a spin-coated V2O5–LC polymer hybrid film, revealing height differences in the range of ca. 100-300 nm. The measured absorbance for a film shown in this graph is ca. 0.23. ... 237 Figure S38: Electrochromic device used for studying the electrochromic performance of V2O5–LC polymer hybrid films. ... 238 Figure S39: Long-term stability of the V2O5–LC polymer hybrid film, which is described in Figure 5.10 and Figure 5.11. After over 100 switching cycles (black curve:

switching cycles 91-96; -0.5V–1.5 V; sweep rate of 50 mV s^-1), the electrochromic device was stored for more than 1 month. Applying alternating potentials (-0.5V–1.5 V;

sweep rate of 50 mV s^-1) after storing reveals a similar cycling behaviour (red curve).

The decrease in transmittance change of ~20% is mainly attributable to the higher initial transmittance at 450 nm of the film in the oxidized state. ... 238 Figure S40: Determination of the response time of oxidation and reduction step of the V₂O₅–LC polymer hybrid species upon applying alternating potentials from -0.5 V and 1.5 V with a sweep rate of 50 mV s^-1. ... 239 Figure S41: UV-visible spectra of hybrid particles (normalized) consisting of CTAB- coated gold nanorods and LC polymer in DMF. The spectra do virtually not change over a time span of 3 weeks; (a) before and (b) after 3 weeks. ... 240 Figure S42: Characterization of bassanite and/or gypsum particles formed upon addition of different volumes (10 or 100 mL) of 25 mM CaSO₄ solution into 500 mL ethanol.

The particles were isolated by centrifugation and subsequent drying in vacuum at room temperature. (a) IR spectra showing typical peaks for bassanite or gypsum in different

Hierarchically Structured Composite Materials by Gluing of Anisotropic Nanoparticles