The living anionic copolymerization of isoprene (I) and styrene (S) can afford a variety of different polymer microstructures that strongly depend on experimental parameters such as solvent, counterion, and temperature. In this work, in situ near-infrared (NIR) spectroscopy was employed as a versatile and fast method to track the conversion of the individual monomers in a nonpolar (cyclohexane, CyH) and a coordinative solvent mixture (CyH with 1.5% vol tetrahydrofuran (THF)). For the first time, in situ monitoring of the copolymerization is performed by deriving the individual monomer signals from the superimposed spectra using the molar attenuation coefficients of each component in the wavenumber range of 5900−6250 cm −1 . The polymerization in nonpolar solvents features a unique kinetic behavior and is known to result in tapered block copolymers. Kinetic rate constants and the corresponding activation energies were determined in CyH, covering a broad temperature range of 10−60 °C. Paralleling the experimental studies, the polymerization was also simulated in silico by feeding the measured kinetic rate constants into a kinetic Monte Carlo simulation (kMC). This combination of in situ monitoring and kMC simulation allows to reduce reaction times, which is especially desired in multiblock syntheses. The observed differences in activation energies aid in understanding the temperature dependence of the reactivity ratios. Thus, temperature can be used as an external parameter to adjust the gradient and the size of the polystyrene block. The peculiar temperature dependence of the gradient affects the resulting bulk morphology. This led to a surprising partial change from the lamellar to the tetragonally cylindrical or perforated lamellar structure at the identical isoprene/styrene composition, only caused by a change of the polymerization temperature. In situ NIR probing is established as a fast and accurate method for real-time copolymerization monitoring that enables tracking complex copolymerization procedures, such as multiblock formation with a temporal resolution exceeding current standards set by 1 H NMR kinetics.

Catalysis is one of the most important processes in nature, science, and technology, that enables the energy efficient synthesis of essential organic compounds, pharmaceutically active substances, and molecular energy sources. In nature, catalytic reactions typically occur in aqueous environments involving multiple catalytic sites. To prevent the deactivation of catalysts in water or avoid unwanted cross-reactions, catalysts are often site-isolated in nanopockets or separately stored in compartments. These concepts have inspired the design of a range of synthetic nanoreactors that allow otherwise unfeasible catalytic reactions in aqueous environments. Since the field of nanoreactors is evolving rapidly, we here summarize—from a personal perspective—prominent and recent examples for polymer nanoreactors with emphasis on their synthesis and their ability to catalyze reactions in dispersion. Examples comprise the incorporation of catalytic sites into hydrophobic nanodomains of single chain polymer nanoparticles, molecular polymer nanoparticles, and block copolymer micelles and vesicles. We focus on catalytic reactions mediated by transition metal and organocatalysts, and the separate storage of multiple catalysts for one-pot cascade reactions. Efforts devoted to the field of nanoreactors are relevant for catalytic chemistry and nanotechnology, as well as the synthesis of pharmaceutical and natural compounds. Optimized nanoreactors will aid in the development of more potent catalytic systems for green and fast reaction sequences contributing to sustainable chemistry by reducing waste of solvents, reagents, and energy.

A templating method is developed to produce porous nanocrystalline anatase materials for negative electrodes in lithium‐ion batteries (LIBs). Amphiphilic diblock copolymers are used to generate template films with phase‐separated internal structure. Subsequent swelling with acidified titanium(IV) bis(ammonium lactato) dihydroxide (TALH) solution yielded structured hybrid films. Upon heating, the formation of TiO2 nanocrystals is induced, resulting in a three‐dimensional mesoporous structure directed by the bulk morphology of the polymer template. In comparison to commercial nanosized anatase, the structured anatase shows significant performance improvements in lithium‐ion coin cell batteries in terms of capacity, stability, and rate capability. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1890–1896

Hybrid inorganic/block copolymer (BCP) materials have become increasingly relevant for application in heterogeneous catalysis, microelectronics, and nanomedicine. While block copolymer templates are widely used for the formation of inorganic nanostructures, multicompartment templates could give access to more complex shapes and inner structures that are challenging to obtain with traditional processes. Here, we report the formation and characterization of hybrid platinum/polymer helices using multicompartment nanofibers (MCNFs) of polystyrene-block-polybutadiene-block-poly­(tert-butyl methacrylate) (PS-b-PB-b-PT) triblock terpolymers as templates. Cross-linking of a PS-b-PB-b-PT helix-on-cylinder morphology resulted in uniform nanofibers with a diameter of 90 nm and a length of several micrometers, as well as an inner PB double helix (diameter 35 nm, pitch 25 nm, core 12 nm). The PB double helix served as template for the sol–gel reaction of H2PtCl6 into hybrid Pt double helices (Pt@MCNFs) as verified by STEM, electron tomography, AFM, and SEM. Carbonization of the Pt hybrids into Pt decorated carbon nanofibers (Pt@C) was followed in situ on a TEM heating state. Gradual heating from 25 to 1000 °C induced fusion of amorphous Pt NPs into larger crystalline Pt NP, which sheds light on the aging of Pt NPs in BCP scaffolds under high temperature conditions. The Pt@MCNFs were further sulfonated and incorporated into a filter to catalyze a model compound in a continuous flow process.

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ABC triblock terpolymers are promising soft templates for organic/inorganic hybrids because of their ability to form nanostructures with complex shapes, multiple compartments, and precisely localized chemistry. Exemplified on multicompartment nanofibers (MCNFs) of triblock terpolymers, it is demonstrated that microdomains can be selectively loaded, thereby giving access to nanoscale multimetallic hybrid materials. MCNFs with micrometer length, homogenous diameter (90 nm), and a helix‐on‐cylinder morphology are formed from polystyrene‐block‐polybutadiene‐block‐poly(tert‐butyl methacrylate) (PS‐b‐PB‐b‐PT). After postmodification (cross‐linking/hydrolysis), selective loading with FeCl3, PdCl2, H2PtCl6, AgNO3, CuCl2, or ZnCl2 leads to a variety of hybrid MCNFs analyzed by transmission electron microscopy, scanning transmission electron microscopy, electron tomography, energy‐dispersive X‐ray spectroscopy, and atomic force microscopy. Mild sulfonation of the PS shell to polystyrene sulfonate renders the MNCFs water‐dispersible and allows the formation of mixed‐bimetallic Pt/Pd/Pt@MCNFs and trimetallic Pt/Pd/Ag@MCNFs. It is demonstrated that the order of loading is key to successfully create multimetallic nanostructures. These and other structures can become useful for energy applications as well as in photo‐ and electrocatalysis.