Application of twin polymerization by a base-catalysed, surface-mediated coating procedure is shown on different templates. Post-polymerization treatment leads to microporous shells on MWCNTs, N-doped carbon particles, and copper particles.

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Synthesis, characterization and electrochemical evaluation of composite electrodes – synthesized via twin polymerization – for utilization in vanadium redox flow batteries.

Water-soluble bis(N-acylpiperidone)s with aldehyde-like reactivity are reported to react rapidly with polyvinylamine at room temperature, providing unprecedented clean reaction products. Unlike most amine/ketone reactions that result in arbitrary mixtures of imines, aminals, hemiaminals, or hydrates, in the present study hemiaminals, aminals, or hemiaminal/aminal mixtures are exclusively found. Detailed NMR spectroscopy of solutions, gels, and solids, aided by model reactions, reveals that the hemiaminal/aminal ratio depends on pH, water content, and crosslinking density. Network formation is fully reversible upon changes in pH, with the resulting moduli from rheology spanning almost 3 orders of magnitude. The selfhealing ability of the system is probed by rheology as well, demonstrating maintained material properties of fractured and healed samples. The unusually clean, fast, and reversible chemistry highlights bispiperidones as a class of efficient building blocks with unprecedented possibilities in dynamic covalent chemistry.

The solvatochromic ThTCF probe responds to anion coordination. Correlations of UV/Vis data from ThTCF with various basicity-related polarity scales (Kamlet-Taft β, Freire EHB, Laurence β1) allow an evaluation of their physical significance.

The surface modification of textile fibers by coating with nanostructured organic–inorganic hybrid materials is presented. The hydrophobic, solvent resistant and mechanically robust coatings were produced by combining the twin monomer 2,2′‐spirobi[benzo‐4H‐1,3,2‐dioxasiline] (TM) and polyalkoxysiloxanes (silica precursor polymers) in a catalyzed polymerization process. For the application in textile finishing, both aqueous emulsions and ethanolic solutions of mixtures were developed. The precisely adjusted ratio of TM and polyalkoxysiloxanes enabled controlling of the organic and inorganic portions in the hybrid layer. The polymerization process can be advantageously combined with the ring‐opening polymerization of hexamethylcyclotrisiloxane (HMCTS). The resulting ethanolic twin prepolymer solutions and the polyethoxysiloxane emulsions were easy to handle and thus represent a novel and attractive binder for PET surfaces. The coated fabrics were analyzed by means of scanning electron microscopy and X‐ray photoelectron spectroscopy showing hybrid material formation as a homogeneous, sealed surface layer. Improved hydrophobicity as well as resistance to mechanical stress was proven by water droplet‐ and Martindale tests.

Polyamide 6/SiO2 hybrid materials were produced by a coupled polymerization reaction of three monomeric components namely 1,1',1'',1'''-silanetetrayltetrakis-(azepan-2-one) (Si(ε-CL)4), 6-aminocaproic acid (ε-ACA) and ε-caprolactam (ε-CL) within one process. Si(ε-CL)4 together with ε-ACA has been found suitable as precursor monomer for the silica and PA6 component. The accurate adjusting of the molar ratio of both components, as well as the combination of the overall process for producing the polyamide 6/SiO2 hybrid material with the hydrolytic ring opening polymerization of ε-caprolactam is of great importance to achieve homogeneous products with a low extractable content. Water in comparison to ε-ACA has been found unsuitable as oxygen source to produce uniformly distributed silica. The procedure was carried out in a commercial laboratory autoclave at 8 bar initial pressure. The molecular structure and morphology of the hybrid materials have been investigated by solid state 29 Si and 13 C NMR spectroscopy, DSC, FTIR spectroscopy and electron microscopic measurements.

Nanostructured aniline formaldehyde resin/polysilazane hybrid materials are produced by twin polymerization of 2,2′‐spirobi[3,4‐dihydro‐1H‐1,3,2‐benzodiazasiline] (1). An alternative synthetic concept for similar hybrid materials, the apparent twin polymerization, is employed by using the combination of the deficient twin monomer tetrakis(phenylamino)silane (2) with hexamethylenetetramine (HMTA). Both processes for the synthesis of polysilazane hybrid materials occur under volatilization of byproducts such as ammonia or aromatic nitrogen compounds. The thermal properties of the twin monomer 1 and the combination of 2/HMTA, respectively, are investigated by differential scanning calorimetry and thermogravimetric analysis. Aniline‐formaldehyde resin/polysilazane hybrid materials are characterized by solid state 13C‐ and 29Si‐NMR spectroscopy and transmission electron microscopy. The inorganic network remains hydrolyzable and can be functionalized after polymerization at temperatures below 500 °C due to residuary reactive Si−N bonds. Thermal treatment at 1100 °C leads to the formation of amorphous Si/C/N hybrid materials.