Mechanically robust, highly toughened, corrosion and impact resistant epoxy/silica nanocomposites by UV curing 3D printing technology

In this paper, a photosensitive resin was successfully synthesized using epoxy as a matrix and the effect of nanosilica on its properties was investigated. Micromorphology analyses show that the nanosilica has good dispersion and strong interaction with the matrix. Additionally, a finite element model was developed to predict the tensile performance of the nanocomposite under high-strain loads. Molecular dynamics simulations demonstrated a favorable binding energy between nanosilica and epoxy resin. The effects of nanosilica on the fracture toughness and energy release rate of photosensitive resins were investigated using load-enhanced tensile test method. The results showed that the addition of 1.0 wt.% nanosilica particles increased the toughness of the resin from 0.45 MPa m^1/2 to 0.79 MPa m^1/2, and the energy release rate from 248.3 J/m² to 555.7 J/m²; compared with the neat photosensitive resins, the incorporation of nanosilica increased the tensile and impact strengths of the resins by 26.8% and 49.2%, respectively. The nanosilica was used to improve the tensile strength and impact strength of the resin by 26.8% and 49.2% respectively compared with the neat photosensitive resin. Electrochemical corrosion analysis showed that the photosensitive resin/nanosilica composites have excellent corrosion resistance. Under different corrosion environments of acid, alkali, and salt, the addition of 1 wt.% nanosilica in the photosensitive resin composite led to an increase in corrosion voltage by 0.023 V, 0.004 V, and 0.1 V respectively compared to neat photosensitive resin. Additionally, the corrosion current density decreased by 1.39 × 10⁻⁶ A/cm², 0.525 × 10⁻⁴ A/cm², and 2.57 × 10⁻⁶ A/cm², respectively. On this basis, the independently synthesised photosensitive resin has excellent strength and 0.01 mm printing accuracy.