Characterization of modified safflower oil-reinforced epoxy resins: assessment of curing kinetics and mechanical performance

Abstract

In this study, modified safflower oil (MSO) is synthesized using safflower oil as bio-based epoxy resin raw material and its curing behavior is investigated. The main objective is to assess the influence of MSO incorporation on the curing kinetics and tensile properties of epoxy composites while aiming to optimize the processing conditions. For this purpose, 10 mass% of MSO is incorporated into neat epoxy resin, and the curing behavior is evaluated using isothermal differential scanning calorimetry (DSC) at 80, 90, and 100 degrees C. The experimental data are modeled using the Kamal-Sourour kinetic model, and activation energies are calculated through Arrhenius analysis. Mechanical performance is assessed via tensile tests conducted according to ISO 527-1 standard, and the results are statistically analyzed and optimized using response surface methodology (RSM). The results reveal that the addition of MSO led to slight modifications in curing kinetics, characterized by increased activation energy compared to neat epoxy. In terms of mechanical properties, the MSO-modified composites exhibit improved tensile strain values by approximately 20-50%, while tensile strength shows a reduction of 2-8% relative to neat epoxy. RSM optimization indicates that the most favorable results are obtained at a curing temperature of approximately 92.7 degrees C with 8 mass% MSO content. These findings suggest that MSO can be used as a partial replacement in epoxy systems to support the development of more sustainable composites by reducing petrochemical dependency and enhancing selected mechanical properties.