عنوان مقاله [English]
Hypothesis: Today, thermoset resins are one of the most widely used resins in various industries including aerospace and automotive industries. In this respect, epoxy resins are of particular importance. Strengthening the mechanical properties of this resin for use in special applications has always been a requirement of the industry. Thereby, an attempt was made to improve the tensile modulus of epoxy resin using benzoxazine resin based on aniline and bisphenol A (BA-a) and silica nanoparticles (Si).
Method: Due to the lack of availability of epoxy resin and to achieve the scientific ability of producing epoxy-benzoxazine composites, benzoxazine resin was synthesized by solvent method and then the solvent was removed. Subsequently, Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR) and differential scanning calorimetry (DSC) tests were used to verify the structural nature of the synthesized resin and evaluate its thermal properties. After making sure that the benzoxazine resin was produced and familiarized with its process properties, epoxy resin blending was performed.
Finding: The results of this work showed that the tensile modulus of epoxy-benzoxazine-based composite (80:20 wt/wt%) (EB-82) (3.9 GPa) is 17% higher than a neat epoxy resin (3.33 GPa). By increasing the amount of benzoxazine resin to 30%, the mechanical properties did not change. Therefore, EB-82 was used to make other composites. In nanocomposites with 2 and 4 wt% nanosilica, the tensile modulus increased to about 26 and 51% (4.1 and 1.5 GPa, respectively). These interesting results were attributed to the good interaction between the components and the good filler dispersion.