Qiaolin Tang’s research while affiliated with Southwest University of Science and Technology and other places

Epoxy resins offer broad applications but are limited by their mechanical strength. This study enhances the properties of an indole-based epoxy resin (EPI) through the incorporation of europium ions (Eu ³⁺ ), leveraging their cation-π interactions. A red fluorescent indole-based epoxy resin (Eu@HEr) was synthesized, emitting at 616 nm under Ultraviolet (UV) light. Eu@HEr exhibited a 42% increase in tensile strength (86 MPa) and a 114% improvement in elongation at break (10.9%) compared to EPI. The thermal decomposition temperature of Eu@HEr rose by 64 °C, indicating superior thermal stability. These findings highlight the potential for high-performance epoxy resins with dual mechanical and luminescent properties.

The intrinsic compromise between strength and toughness in composite epoxy resins significantly constrains their practical applications. In this study, a novel strategy is introduced, leveraging interfacial π‐π stacking interactions to induce the “rolling behavior” of microsphere fillers, thereby facilitating efficient energy dissipation. This approach is corroborated through theoretical simulations and experimental validation. The resulting composite epoxy resin demonstrates an impressive 49.8% enhancement in strength and a remarkable 358.9% improvement in toughness compared to conventional epoxy resins, accompanied by substantially reduced hysteresis. Moreover, this system achieves reversible closed‐loop recyclability and rapid repair capabilities. The preliminary demonstration of “force‐temperature equivalence” further establishes a novel pathway for the design of high‐performance composite epoxy materials.

Silica (SiO₂) serves as a reinforcing filler, while titanium dioxide (TiO₂) functions as a functional filler, imparting exceptional mechanical strength and UV resistance to silicone rubber. However, compatibility issues may arise when both fillers are incorporated into silicone rubber. This study explores potential solutions through processing methods, specifically by comparing the effects of graded filling and mixed filling on the properties of silicone rubber. Field emission scanning electron microscopy reveals that the mixed filling method promotes a more uniform dispersion of fillers, leading to enhanced performance. Curing tests indicate that the effect of the filling method on the curing processing performance of silicone rubber is negligible. Tensile test results reveal that, compared to the graded filling system, the mixed filling system improves the tensile strength and elongation at break of the silicone rubber composites by 13% and 13.4%, respectively, while simultaneously reducing the Mullins effect, thereby enhancing material stability. Thermogravimetric analysis (TGA) and differential thermal analysis (DTG) results indicate that the uniform dispersion achieved through mixed filling optimizes thermal transfer pathways, resulting in superior thermal stability compared to graded filling. Ultraviolet (UV) spectroscopy results demonstrate that composites containing added TiO₂ exhibit almost zero transmittance in the UV range of 200-400 nm, underscoring their excellent UV resistance; the mixed filling method provides superior UV protection compared to the graded fill method. In summary, for the dual-filler system of SiO₂ and TiO₂, the mixed filling approach enhances filler compatibility by improving dispersion, thereby elevating material performance and broadening potential applications.

A strong and tough indole‐based epoxy film driven by cation–π interaction is designed, evading the trade‐off between stiffness and extensibility in epoxy resins. The film with high strength, toughness and effective anti‐counterfeiting properties induced by cation–π interaction is promising in the development of the fields of aerospace and electronic devices. © 2023 Society of Industrial Chemistry.