Mechanical and Thermophysical Properties of Epoxy Nanocomposites with Titanium Dioxide Nanoparticles

The introduction of nanoparticles and their homogeneous distribution in the polymer matrix, as well as their size, can have a significant effect on the mechanical properties of composite materials. In this work, we studied the mechanical characteristics of TiO2/epoxy nanocomposites with different contents and sizes of nanoparticles. The preparation of nanocomposites was carried out by a stepwise curing (at 90 and 160 °C) of ED-20 dianic epoxy resin in the presence of an aromatic hardener with the addition of titanium (IV) dioxide nanoparticles preliminarily synthesized by the plasma-chemical method. Ultrasonic dispersion was used to achieve a uniform distribution of nanoparticles in the polymer matrix. The chemical and phase composition, the structure of the as-synthesized TiO2 nanoparticles, and the resulting epoxy nanocomposites were characterized by elemental analysis, X-ray diffraction, transmission and scanning electron microscopy, and infrared spectroscopy. The mechanical properties of the nanocomposites were determined by the static tensile test, and the impact toughness was determined by the Charpy method. The glass transition temperature and thermal stability of the TiO2/epoxy nanocomposites were studied by thermal analysis methods. The formation of an interfacial layer between the TiO2 nanoparticles and an epoxy matrix has been shown for the first time by spectral methods. It is shown that the mode of curing and ultrasonic dispersion used, as well as varying the content and dispersity of the TiO2 nanoparticles, make it possible to obtain epoxy nanocomposites with simultaneously improved deformation-strength characteristics and impact strength values.