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We report on the preparation of all-silica colloidosomes with adjustable size, shell structure, mechanical strength, and permeability. Our approach is based on the coassembly at the water/oil interface of silica nanoparticles and a silica precursor polymer-hyperbranched polyethoxysiloxane-which acts as a binder for particles as well as an additional interfacial component. Remarkably, the shell of colloidosomes can be fine-tuned from a particle monolayer up to a bilayer bound with a sandwiched thin silica film. This method presents a facile approach toward multiscale production of microcapsules which have a high potential in encapsulation technology and in smart coating formulations.

Complexes consisting of poly(4-vinylpyridine) and mesogenic wedge-shaped ligands 4'-[3",4",5"-tris(dodecyloxy)benzoyloxy]azobenzene-4-sulfonic acid and 4'-[3",4",5"-tris(octyloxy)benzoyloxy]azobenzene-4-sulfonic acid have been prepared with different monomer/ligand ratios. Upon protonation of the poly(4-vinylpyridine) chains by the wedge-shaped sulfonic acid molecules a hypsochromic and hyperchromic effect was observed with the pi-pi* transition of the azo-chromophor, allowing us to monitor the neutralization process by means of UV-vis spectroscopy in solution. The changes of the absorption characteristics implied a conformational change of the polymer backbone. In the bulk the interaction between pyridine and sulfonic acid moieties was proved by FT-IR spectroscopy. Polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction measurements were used to study the bulk structure of the complexes. The complexes formed a liquid crystalline lamellar phase at low degrees of substitution, while a hexagonal columnar mesophase was observed at degrees of neutralization of 80% and higher.

Wedge-shaped molecules with a sulfonic group at the tip have been incorporated into a poly(2-vinylpyridine)-b-poly(ethylene oxide) (P2VP-b-PEO) diblock copolymer via proton transfer at different degrees of neutralization. The protonation of P2VP was monitored by means of Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The thin film morphology of the complexed block copolymers has been studied by scanning force microscopy and X-ray reflectivity. The complexes exhibit strongly microphase-segregated patterns comprising smectic layers of the complexed P2VP blocks, oriented parallel to the substrate throughout the whole film with the embedded PEO domains. For the complex with a degree of neutralization of 0.50 ordered amorphous PEO cylinders are observed oriented perpendicular to the substrate. For a degree of neutralization equal to 0.25 initially also perpendicular PEO cylinders are formed, but upon solvent-vapor annealing they partially merge, resulting in a mixed lamellar-cylindrical morphology. In all cases an extra surface layer is formed at the substrate. Thus, for the first time we have demonstrated that a block copolymer thin film structure can easily be controlled by the degree of neutralization of one of the blocks.

Hyperbranched polyethoxysiloxanes were prepared via a one-pot synthetic route based on a condensation reaction of tetraethoxysilane with acetic anhydride in the presence of an organotitanium catalyst. Volatile compounds can be fully removed using a thin-film evaporator. According to size-exclusion chromatography and viscosity measurements, the average molecular weight as well as the molecular weight distribution of the products increased exponentially by increasing the molar ratio of acetic anhydride to tetraethoxysilane from 1.0 to 1.2. At the molar ratio 1.3, a solid gel was formed. The liquid products are stable and hydrophobic; they are miscible with most organic solvents. 29Si NMR spectroscopy and MALDI-ToF mass spectrometry show that they have a hyperbranched structure with additional internal loop formation.

A novel wedge-shaped amphiphilic molecule bearing a sulfonate group at the tip displays humidity-induced phase transitions from a hexagonal columnar structure to a bicontinuous cubic phase. The mesophases can be frozen by photopolymerization of acrylic end-groups resulting in free-standing membranes with different topology of ionic nanochannels. The obtained membranes with a well-ordered ionic channel structure hold promise for applications in separation and catalysis.

The synthesis of 4-N-[3',4',5'-tris(dodecyloxy)benzamido]benzene-4-sulfonic acid (1) and 4'-[3",4",5"-tris(dodecyloxy)benzoyloxy]azobenzene-4-sulfonic acid (2) is described. Pure acid 1 is stable, while 2 can be stored only in solution. Both acids were obtained from their sodium salts and were quantitatively transformed into the pyridinium salts. The phase behavior of these acids, as well as the sulfonates was investigated by differential scanning calorimetry and polarizing optical microscopy. The investigated compounds exhibit columnar mesophases. The formation of columnar superstructures was demonstrated for the sodium sulfonates by scanning force microscopy, gelation experiments, and proton magnetic resonance spectroscopy.

Designing antimicrobials with high-efficiency and long-term antibacterial activity is an imperative issue. We found that the antimicrobial effect of Ti3C2Tx and Ag/Ti3C2Tx could be significantly strengthened upon the near-infrared light...