Preparation and Mechanical Properties of Polyurethane‐Based Graphite Tailings Mortar

ABSTRACT With the growing demand for environmentally friendly materials in the construction industry, the utilization of tailings resources has become increasingly important. Polyurethane (PU), a fast‐curing polymer with high viscosity and flexibility, has been widely used in construction materials. This study combined PU and graphite tailings (GT) to prepare polyurethane‐based graphite tailings (PUGT) mortar and investigated how PU content governs mechanical performance and pore evolution through mechanical testing, mercury intrusion porosimetry, and multiscale observations. At PU:GT = 1:1.5, PUGT mortar achieved compressive and flexural strengths of 38.98 and 25.06 MPa, respectively, indicating a balanced combination of load‐bearing capacity and toughness within the tested range. Porosity results showed that increasing PU reduced micropores and improved densification, whereas excessive PU promoted larger pores that can adversely affect overall performance. These findings support the resource utilization of GT and the potential application of PUGT mortar as a building material.