The application relates to the technical field of cementing materials, and discloses a cementing
slurry for improving the cementing strength of an interface
coal rock, a preparation method and application of the cementing
slurry, which is composed of 50-150 parts of
oil well cement, 5-50 parts of
epoxy resin, 0.2-2 parts of a slow-release curing agent, 0.05-0.2 parts of a defoaming agent, 1.75-11 parts of an auxiliary agent and 40-80 parts of water in terms of
mass fraction; the slow-release curing agent is prepared by
substitution reaction and complexation reaction of
imidazole organic matter,
propylene carbonate and a
transition metal chloride; the cementing
slurry has good rheological performance, adjustable density, excellent
compressive strength and low Young's modulus after
cement curing, and can improve the cementing strength of the
coal rock and the
cement ring; the slow-release curing agent can be gradually released along with the cement
hydration reaction, the crosslinking rate of the
epoxy resin can be accurately controlled, the problem of abnormal thickening of the
epoxy resin cementing slurry can be solved, a high-strength-low-elastic-modulus-strong-cementing
resin cement composite material meeting the requirements of
coal rock gas cementing can be formed, the safety of cementing construction can be ensured, and the long-term performance stability of the
resin cement ring can be ensured.