Abstract:To enhance the grouting effectiveness in complex geological formations and address the issues of poor injectability and slow curing of traditional cement-based materials, the influence of the mass ratio (0.1~1.2) of isocyanate to water glass on the performance of polyurethane/water glass composite materials is studied. Single-factor experiments are conducted to measure the gel time, curing time, reaction temperature and uniaxial compressive strength of polyurethane/water glass composites. The microstructure of the material is analyzed in combination with a scanning electron microscope. The results show that the comprehensive performance of the material is the best, and the compressive strength is the highest, reaching 57.3 MPa when the mass ratio of isocyanate to water glass is 0.6~0.9, and it has a fast gel time and curing time, which can meet the requirements of leak sealing and surrounding rock reinforcement. When the mass ratio is less than 0.4, the material is difficult to cure. When the mass ratio is greater than 1.0, the compressive strength of the material decreases. Microscopic analysis shows that an appropriate mass ratio can promote the formation and uniform distribution of silicate microspheres, thereby enhancing the mechanical and curing properties of the material. Therefore, it is recommended that in practical engineering applications, the mass ratio of isocyanate to water glass be controlled at 0.6~0.9 to balance strength performance, construction feasibility and material economy.
