Preparation and characterization of elevated and cryogenic temperature-resistant regolith-based epoxy resin composites

The construction of lunar bases, with their crucial role in future deep space exploration and extraterrestrial resource harvesting, requires the integration of multiple manufacturing techniques. Selecting appropriate solu-tions to meet the feature requirements is of particular importance. Extreme environments on lunar surfaces pose uphill challenges for construction, and transportation between Earth-to-Moon involves costs and risks. In-situ utilization of lunar regolith for fabrication has been proven feasible, among which polymer forming possesses promising prospects due to its sample manufacturing process, excellent mechanical properties, and low energy consumption. To investigate the feasibility of regolith-based polymer composites, specimens with varying pro-portions were prepared based on the Taguchi method. The lunar regolith simulants (LRS) and resulting polymer were characterized by laser particle analyzer and X-ray diffraction (XRD), Fourier Transform Infrared Spec-troscopy (FTIR), and scanning electron microscopy (SEM). Their elevated (180C) and cryogenic (-196C) tem-perature resistance properties were investigated by compressive and flexural strength tests after shifting freeze-thaw cycle tests. The results revealed that curing temperatures and mass ratio of curing agents to the hybrid epoxy matrix significantly affect the compressive strength and flexural strength, respectively. The maximum 24 h compressive and flexural strength of regolith-based polymer composites was obtained as 156.22 MPa and 103.40 MPa, respectively. And remained stable over 160 MPa and 70 MPa after ten freeze-thaw cycles. Microstructural results imply variations in the curing agent's and aggregate's ratio, which tentatively explain the reaction mechanism of regolith-based polymer composites. This study demonstrates the feasibility of preparing polymer utilizing LRS that accommodates immense temperature fluctuation on the Moon, with undemanding fabrication, excellent mechanical properties, and low energy consumption, providing potential applications for future lunar construction, especially for rapid repair and reinforcement of launch pads and runways.