Plasticized epoxy composites for manufacturing of composite reinforcement

Composite rebar is a promising building material due to its advantages over steel rebar. Polymer reinforcement consists of a hardened matrix reinforced with a continuous fiber. The main role of the matrix is to determine the performance properties of the composite and to distribute stresses in the reinforcing filler. Optimization of the polymer matrix composition in terms of strength and technical parameters makes it possible to obtain a composite with high performance properties. The aim of the research was to determine the effect of modifying additives on the properties of the matrix for the production of composites with high technical requirements. When performing research, we considered modifiers that interact differently with the components of the polymer matrix as plasticizers. The first type of additive is able to combine with reactive groups of epoxy resin to form a three-dimensional product. Urea resin was used as such a compound. The second group of samples contained a furfurolacetone monomer-a substance that does not contain reactive groups with the resin, but interacts with the hardener of the epoxy resin. And the third type of modifier is dioctyl phthalate, whose role is to change the intermolecular and intramolecular interaction of the spatial structure that it fills. Optimization of compositions to identify areas with high physical and mechanical values was carried out using mathematical methods of experiment planning. Based on the results of the research, it can be concluded that with the optimal content of plasticizers, in all cases, there is an increase in the compressive and tensile strength indicators compared to materials without additives. Further increase in the content of modifying additives (above the optimal amount) leads to a decrease in strength.