This invention discloses a high-strength, high-foaming-rate, low-
viscosity oil-based
polyurethane grouting material and its preparation method. The material comprises, by weight, 65-85 parts PMDI, 10-20 parts low molecular weight polyether
polyol, 1-6 parts octahydroxy-POSS, 5-15 parts
epoxy resin
reactive diluent, 3-8 parts high-boiling-point
solvent, 0.5-2.5 parts composite foaming catalyst, 1-3 parts
trimer and
epoxy ring-opening composite catalyst, and 1-2 parts foam stabilizer. This invention eliminates traditional
volatile solvents and constructs an in-situ interpenetrating crosslinked network of "nanocage-type
silsesquioxane (POSS)-
epoxy resin-
polyisocyanurate (PIR)". According to JC / T2041-2020 testing, this material not only has extremely low
viscosity (≤400mPa·s) and extremely high non-volatile matter (≥95%), but also breaks the mechanical curse of conventional foamed materials. Under extreme foaming conditions such as rapid solidification upon contact with water (≤30s) and foaming rate ≥4000%, the
compressive strength is still as high as 30MPa or more. It completely solves the global problem that high foaming of materials in leak sealing and reinforcement projects inevitably leads to low strength, and has excellent
environmental protection and structural reinforcement
pressure resistance.