Low-temperature mechanical properties of polyurethane-modified waterborne epoxy resin for pavement coating

The purpose is to clarify the development law of mechanical properties of waterborne epoxy resin coatings at low temperatures and further promote its application in cold areas. Different types of polyurethane-modified waterborne epoxy resins were prepared. The development law of low-temperature mechanical properties of waterborne epoxy resin at different curing time was studied systematically. The improvement effect of polyurethane on the mechanical properties of waterborne epoxy resin at low temperatures was evaluated. The prediction models of low-temperature mechanical properties of waterborne epoxy resin based on Grey–Markov chain method was established. The results show that the mechanical properties of waterborne epoxy resin decrease after low-temperature treatment for 15 days. Its strength and flexibility are reduced by 3% and 10%. Polyurethane could improve the low-temperature durability of waterborne epoxy resin. The retention rates of the various mechanical properties of modified waterborne epoxy resin increase significantly. Among them, the retention rate of elongation at break increases by more than 50%, and the bending deformation is almost no longer attenuated. The prediction model based on BP–Elman neural network has a higher accuracy, and the relative error is less than 0.04%.