PREPARATION AND STUDY OF A PU-MODIFIED EPOXY RESIN COLD PATCHING MIXTURE

Focusing on the problems of low strength and insufficient water stability of the cold patch mixture for asphalt pavement, a polyether polyurethane prepolymer with high activity was prepared in this experiment, and then the epoxy resin was modified with the prepolymer to prepare a kind of epoxy-resin-mixture pothole-repair material with high strength and high toughness. The content of polyurethane prepolymer was optimized using a low-temperature tensile test and a normal-environment-condition mechanical test, and the mechanical properties and road performance of the PU-modified epoxy-resin mixture were studied with a rutting test, bending test, Cantabro scattering and a splitting test. The results show that PU prepolymer-modified epoxy resin can effectively increase the toughness and strength of the binder, and that the toughness and mechanical properties of 20 phr PU prepolymer are the best. The road performance of the PU-modified epoxy-resin cold patch mixture is excellent. There is little difference between the immersion scattering loss rate and the standard loss rate, and both are less than 4 %, indicating that the mixture has excellent anti-scattering and water-loss performance. It is very suitable as a cold patch material for pavement pits. Due to its comprehensive road performance and reasonable price, the use of the PU-modified epoxy resin binder content of 4 % is recommended.