A two-step modification strategy is applied to tailor the particle–matrix interface in zirconia nanoparticle–polystyrene composites, achieving strongly enhanced mechanical properties.

Hydrous boehmite (γ-AlOOH) nanoparticles (BNP) show great potential as nanoscale filler for the fabrication of fiber reinforced nanocomposite materials. Notably, the particle− matrix interaction has been demonstrated to be decisive for improving the matrix-dominant mechanical properties in the past years. Tailoring the surface properties of the nanofiller enables to selectively design the interaction and thus to exploit the benefits of the nanocomposite in an optimal way. Here, an extensive study is presented on the binding of (3-aminopropyl)triethoxysilane (APTES), a common silane surface modifier, on BNP in correlation to different process parameters (concentration, time, temperature, and pH). Furthermore, a comprehensive characterization of the modified BNP was performed by using elemental analysis (EA), thermogravimetric analysis (TGA) coupled with mass spectrometry (TGA-MS), and Kaiser's test (KT). The results show an increasing monolayer formation up to a complete surface coverage with rising APTES concentration, time, and temperature, resulting in a maximal grafting density of 1.3 molecules/nm 2 . Unspecific multilayer formation was solely observed under acidic conditions. Comparison of TGA-MS results with data recorded from EA, TGA, and KT verified that TGA-MS is a convenient and highly suitable method to elucidate the ligand binding in detail.

In this contribution, we report the first hard‐X‐ray‐induced thermal hysteresis (HAXITH). The bistability in [Fe(phen)2(SCN)2] (phen = 1,10‐phenanthroline) is proven by alternately heating and cooling the sample under permanent irradiation with hard X‐rays. Within the hysteresis a serpentine‐like switching effect is observed. HAXITH is a new tool to monitor cooperativity among the switching units. It exhibits a threshold similar to that observed with visible light excitations.

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SummaryCoated magnetite nanoparticles were linked to 68Ga complexes used in the positron emission tomography (PET) for a new technical approach to detect cancer tissue with radiopharmaceuticals. By substitution of the Ga isotope with an alpha emitter the same compound could be used for cancer treatment. Furthermore the nanoparticles were connected to pH-sensitive complexes, enabling a pH-controlled assembly/disassembly and therefore the spreading of the particles in the tissue. With this novel method of combining detection and treatment simultaneously, the amount of medical exposure could be minimized for the patient. The results demonstrate that magnetite nanoparticles can effectively be functionalized with PET isotopes and pH sensitive complexes in order to use them as a new type of radiopharmaceuticals.

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By adding nanoparticles to classical polymer systems, new functional materials with tailored properties can be obtained. The great variety of possibilities opens up just as many interesting fields of application for industry and science. Following on from this, this article will present how the classical educational subject area of polymers can be extended by a current research context. In a series of experiments, students are using inexpensive chemicals and simple materials from the hardware store to produce nanocomposites that have a much greater hardness or antimicrobial activity than polymers alone. Their properties can then be investigated using a simple test method. Overall, it will be illustrated, that the combination of polymer chemistry and nanotechnology offers a variety of learning opportunities and questions with curricular relevance for schools and student laboratories.

Nanoadditive machen Polymerprodukte kratz‐ und bruchfest oder keimhemmend. Solche Komposite lassen sich auch in der Schule herstellen und untersuchen – Materialien dafür gibt es im Bau‐ oder im Supermarkt.