Epoxy Composites Modified with Functionalized Aluminosilicate Microspheres from Thermal Power Plant Ash: Complex Improvements in the Mechanical and Thermal Properties

In this paper, the effect of aluminosilicate microspheres (ASMs) from thermal power plant (TPP) ash on the properties of epoxy composites was studied. A method for modifying the ASMs' surface using aminoacetic acid was developed to improve the adhesion at the polymer-filler interface. Complex analysis methods, including scanning electron microscopy, infrared spectroscopy, a thermogravimetric analysis, DSC, and DMA, showed that adding the optimal amount of ASMs significantly improved the physical and mechanical properties of the composites: the flexural strength increased by 112%, the elastic modulus by 198%, and the impact strength by 50%. Functionalization of the ASMs enhances their interaction with the matrix, providing the composites with the best strength and thermal stability indicators among the studied materials. The study of the curing kinetics showed the initiating effect of functionalized ASMs on the curing process of epoxy compositions, associated with the presence of active amino groups on the surface of the particles. The resulting composites demonstrate potential for application in structural and fire-resistant materials; have high-deformation and -strength characteristics; and facilitate the disposal of industrial waste.