A Study on the Application Performance of High-Aspect-Ratio Nano-Ettringite in Photocurable Resin Composites

In this study, the impact of the addition of high-aspect-ratio nano-ettringite to photocurable epoxy acrylate resin was explored. The nano-ettringite samples were modified using γ-Aminopropyltriethoxysilane (KH-550) and γ-methacryloxypropyl trimethoxy silane (KH-570). Then, 3 wt% or 6 wt% KH-550-modified, KH-570-modified, and unmodified nano-ettringite samples were dispersed into resin via ultrasonic treatment in conjunction with mechanical stirring. The grafting effects of nano-ettringite onto KH-550 or KH-570 were analyzed through scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and thermogravimetric (TG) analysis. The results demonstrate that KH-550 and KH-570 have been successfully grafted onto the surface of nano-ettringite. In addition, this study also focuses on the variations of composite materials in the viscosity, shrinkage, tensile strength, and elongation at break. The results indicate that increased dosages of unmodified, KH-550-modified, and KH-570-modified nano-ettringite led to increased viscosity of the composite while reducing shrinkage. At the same dosage, the photocurable resin containing KH-570-modified nano-ettringite demonstrated a lower shrinkage and a higher tensile strength. From the analysis of tensile fracture surfaces, it was observed that compared to the KH-550 modified and unmodified variants, the KH-570 modified nano-ettringite exhibits superior dispersibility in photocurable epoxy acrylate resin. Notably, when the amount of KH-570-modified nano-ettringite was 3 wt%, the highest tensile strength of the composite was 64.61 MPa, representing a 72.57% increase compared to the blank sample. Furthermore, the incorporation of KH-570-modified nano-ettringite as a filler provides a new perspective for improving the performance of photocurable epoxy acrylate resin composites.