Abstract: The methods of formation of silicon dioxide and titanium dioxide nanoparticles by sol-gel method in a polymer molecular grid
are studied. For this purpose, hydrolysis of tetraethoxysilane and tetrabutoxytitane was carried out in an ultrasonic field. The products
were isolated, thermally treated to remove by-products and water, and studied by optical microscopy, IR spectroscopy, combined
differential thermal and thermogravimetric analysis. As a result, highly dispersed, nanoscale, hydrophobic particles with a highly
developed specific surface area were obtained. They contain residual alkoxy and hydroxyl groups on the surface. The dimensions of
silicon dioxide are 10-50 nm, titanium dioxide - 50-150 nm. The size of the particles and the ability to agglomerate are significantly
influenced by the method of mixing the components. Hydrolysis of tetraethoxysilane and tetrabutoxytitane was carried out in an
aqueous emulsion of polydimethylsiloxane rubber using ultrasonic dispersion. Water was removed from the obtained compositions,
they were cured and samples were made for physico-mechanical tests. The tensile strength for rubbers filled with silicon dioxide
increases from 0.7 to 3.0 MPa, the elongation increases from 100% to 140%. Vulcanizates filled with titanium dioxide have a tensile
strength of 0.4-2.7 MPa, elongation of 100-160%. The best results were obtained during the joint hydrolysis. The tensile strength of
these samples is 3.5 MPa, the elongation is 180%. The proposed method of simultaneous sol-gel synthesis in an ultrasonic field of
silicon dioxide and titanium dioxide allows improving the physical and mechanical properties of vulcanizates based on low
molecular weight polydimethylsiloxane rubber.
Index terms: polydimethylsiloxane rubber, tetraethoxysilane, tetrabutoxitane, sol-gel technology, ultrasound, nanoparticles.