|
The subject of rheology research, as a field of science, is the study of the behavior of various phase systems, primarily liquids and gases, subjected to loads over a certain period of time. These include mechanical loads, the influence of electric, magnetic and other fields that can significantly change the intramolecular structure of materials. The main effects of these interactions are elastic, plastic or so-called flowing. With regard to the properties of the tested changes, in liquids, which include epoxy resins, before the hardening process, viscosity (dynamic and kinematic) is most often tested. This property describes the ability of a fluid to resist shear stresses. Their value depends on pressure, temperature and shear rate in the considered medium. The afore-mentioned polymers are very often used in the processes of bonding building materials with different properties due to their good adhesion to the substrate. Nevertheless, the effectiveness of gluing depends largely on the parameters of the adhesive both during the application of the layer and after the hardening process. Adhesives used in construction are often modified by adding fillers. Their effective bonding with the resin can be ensured by the cavitation process. This phenomenon depends on local changes in pressure and temperature in the volume of the liquid subjected to external load. In the case of the described research, the energy of ultrasound (the so-called sonication) was used to homogenize the epoxy adhesive with the selected powder filler. The sonication process was investigated in terms of the cavitation phenomenon occurring in the polymer and its influence on the changes in the adhesive viscosity and the effectiveness of the filler application. As a result, suitability of sonication as a method of resin modification in terms of obtaining a composite material was assessed.
REFERENCES
|
