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Physicomechanical Characteristics of Composite Based on Polyimide Matrix Filled with Tungsten Oxide
The article presents the possibility of obtaining polymer composite materials based on thermoplastic
polyimide and tungsten oxide (WO3) modified with a hydrophobic silicone fluid. Data on surface microscopy,
Vickers microhardness, density, and thermal stability of composites with different tungsten oxide contents
are presented. As a result of modifying tungsten oxide, its surface becomes hydrophobic, and the contact
angle increases from 31° to 101°. The microstructure of the surface of composites has a fine-grained structure
without microcracks and chips. The lowest density material has no filler. With increasing filler content, the
density increases. When the content of the filler is 80 wt %, the density is 4.35 g/cm3. The optimum content
of tungsten oxide filler is 60 wt % as measured by the surface microhardness. The work shows that the introduction
of the proposed filler significantly increases the heat resistance of polyimide. Pure polyimide is stable
up to 425°С, and at a temperature of 680°С, its full thermal decomposition takes place. With increasing content
of modified tungsten oxide in the composite, the rate of mass loss decreases. In the composite containing
60 wt % filler at 680°C, the mass loss is 38%.