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Vol 485, No 2 (2019)
- Year: 2019
- Articles: 3
- URL: https://journals.rcsi.science/0012-5016/issue/view/9261
Physical Chemistry
Polymer–Inorganic Composites Based on Celgard Matrices Obtained from Solutions of (Aminopropyl)triethoxysilane in Supercritical Carbon Dioxide
Abstract
A method has been developed for the fabrication of a polymer-inorganic composite material based on the Celgard polymer matrix by means of the introduction of silica nanoparticles with amino groups into the polymer structure through impregnation of the porous structure with solutions of the aminosilane precursor in supercritical СO2. The presence of inorganic nanoparticles made it possible to noticeably enhance the hydrophilicity of the material, and the absolute wettability of supercritical CO2 was favorable for uniform particle distribution in membrane pores. The particles growing in membrane pores allowed one to reduce the pore size, which opens ways to control ion-transport selectivity.
53-57
A Method for Purification and Modification of a Bone Xenotransplant Material in Biphase Media Containing High-Pressure CO2
Abstract
A promising method was proposed for the first time for purification of animal bone tissue fragments from high-molecular weight compounds in biphase media containing high-pressure CO2 (solutions of carbonic and peroxycarbonic acids). The efficiency of this purification was confirmed by SEM and IR spectroscopy. It turned out that, during the exposure of bone fragments in solutions of carbonic and peroxycarbonic acids at high CO2 pressure, mineral phase components of bone tissue are also extracted, which can be used to obtain highly dispersed hydroxyapatite particles upon extract reprecipitation. The structure and composition of the extracts were investigated by X-ray diffraction and scanning electron microscopy (SEM).
58-62
Dependence of the Strength Properties of Aluminum Materials on the Concentration of ZrO2 Nanoparticles
Abstract
New data were obtained concerning the effect of small additions of zirconia nanoparticles on the strength properties of powder matrices produced by cold pressing of powders with subsequent sintering in a forevacuum. The matrices were either a pure aluminum powder or an aluminum–1.5 vol % copper powder mixture. It was shown that the introduction of nanoadditives to even an insignificant concentration causes a tangible increase in the mechanical properties of the materials, such as tensile, flexural, compressive, and offset yield strengths.
63-65