Modified acid liquor thickening agent and preparation method thereof

The invention provides a modified acid liquor thickening agent and a preparation method thereof, and relates to the technical field of polymerization and oil field fracturing, the method comprises the following steps: carrying out condensation polymerization on sodium lignin sulfonate and allyl halogenated hydrocarbon to obtain a lignin prepolymer; the preparation method comprises the following steps: carrying out condensation polymerization on lacturonic acid and allylamine to obtain a lacturonic acid prepolymer; uniformly mixing acrylamide, (3-acrylamide propyl) trimethyl ammonium chloride, triallyl cyanurate, the lignin prepolymer, the lacturonic acid prepolymer, water and a first initiator, so as to obtain a water-phase solution; uniformly mixing the white oil, the main emulsifier and the auxiliary emulsifier to obtain an oil phase solution; and adding the water phase solution into the oil phase solution for emulsification, then adding a second initiator to initiate a polymerization reaction, and after th