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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