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This article concerns investigation on immobilization of shear thickening fluids (STFs) in form of organogel obtained with the use of oligo(propylene glycol) diacrylate (PPGA) as a crosslinking monomer. The STF used was a suspension of nanosilica in oligo(propylene glycol). Organogel particles were prepared by dropwise addition of the STF containing PPGA into silicone oil followed by thermal cross-linking of the monomer. Organogel particles were used to prepare PUR-matrix composite. The rheological properties of organogels and composites were studied by oscillatory measurements. The measurements showed significant changes in internal structure of the samples, which are most likely connected with shear thickening. It was demonstrated that manufactured composites exhibited 20% higher impact absorption than that of cast polyurethane elastomer. Presented method of STF immobilization allows to obtain organogel particles that can be widely used for intelligent materials preparation due to their good stability and impact absorption ability.

The joint copper-alumina obtained at a solidification condition of Cu/Cu2O eutectic was studied. Experiments involved many different techniques, such as scanning electron microscopy (SEM), X-ray diffractometry, X-ray microanalysis, and transmission electron microscopy (TEM). It was observed that a thin inhomogeneous interfacial layer is present between Cu and Al2O3 ceramics and it consists of two sublayers: the first is nanocrystalline complex oxide CuAlO2. This layer changes progressively into a crystalline CuAl2O4 sublayer. A model of liquid phase bonding between copper and alumina is proposed.