Two known imido vanadium(V) trichloride complexes, [Cl 3 V=N-C 6 H 3 -2,6-Me 2 ] (1) and [Cl 3 V=N-C 6 H 3 -2,6-iPr 2 ] (2), both of which have escaped testing as ethylene polymerization catalyst precursors, were synthesized and their capacity to polymerize ethylene in the presence of the co-catalyst MAO (methylaluminoxane) (Al:V ratio: 1000:1) at 10°C is reported. The resulting polymers, from both cata-

This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. This paper presents the application of the conducting polymer polypyrrole in a pressure sensitive sensor. Polypyrrole was electrodeposited on copper plates using phytic acid as a dopant and cross-linker. A combination of different polymerization durations and potentials were tested to find the polymerization conditions for thin polymer layers and homogenous surface coverage. The morphology of the surface of the polypyrrole films was examined with scanning electron microscopy to study the formation of hollow sphere beads. The polymer layers were sandwiched between two copper sheets to create pressure sensitive sensors and the piezo-resistive effect was tested. For this, increasing forces were applied to the sensors and the resistance was measured. It was found that the polypyrrole layers were pressure sensitive to pressures relevant for bruxism events and had a thickness that is suitable for application in a splint for the detection of awake bruxism.An SEM image of polypyrrole hollow sphere beads at 20 kV and 1000Â magnification.

The heterogenization of 2,6-dimethylarylimido–vanadium­(V) dichloride via chemical tethering on insoluble silica supports is reported. The effects of the silica particle size, drying conditions, and the reaction time were investigated. The drying conditions of the support were found to be a crucial parameter: drying temperatures over 400 °C were needed to achieve successful catalysis. The supported catalytic systems were characterized by Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscopy–energy-dispersive X-ray (TEM-EDX), and inductively coupled plasma mass spectroscopy (ICP-MS), while the polymers were characterized by FT-IR, differential scanning calorimetry (DSC), and rheology. Ethylene polymerization tests were performed employing the prepared heterogenized catalysts with methylaluminoxane/diethylaluminum chloride as a cocatalyst. The supported catalyst precursor, when activated with diethylaluminum chloride, promotes the synthesis of polyethylene with seemingly controlled particle size in the absence of reactor fouling, suggesting the successful immobilization of the complex over the inert support. The resulting polymer shows features of ultrahigh-molecular-weight polyethylene (UHMWPE). These findings present a proof-of-concept for a new approach toward the heterogenization of arylimido–vanadium complexes.