▎ 摘　　要

NOVELTY - Preparing high temperature resistant long-acting fluid loss reducing agent comprises e.g. (1) mixing graphene oxide with N-methylpyrrolidone, carrying sealed ultrasonic dispersion to obtain graphene oxide dispersion, mixing graphene oxide dispersion with 4,4'-diaminodiphenyl ether, stirring the reaction under nitrogen atmosphere, filtering mixture under reduced pressure to obtain pre-modified graphene oxide, first washing the pre-modified graphene oxide with N-methylpyrrolidone, washing with ethanol and water, and drying to obtain modified graphene oxide; and (2) weighing carboxymethyl cellulose, chitosan acetic acid solution, acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, dimethyl diallyl ammonium chloride, vinyl acetate, initiator, and water; mixing acrylamide with water, adding 2-acrylamido-2-methylpropanesulfonic acid, dimethyl diallyl ammonium chloride and vinyl acetate, stirring and mixing, adding carboxymethyl cellulose, chitosan acetic acid solution and initiator. USE - The method is useful for preparing high temperature resistant long-acting fluid loss reducing agent. ADVANTAGE - The fluid loss reducing agent: has excellent fluid loss reduction performance and good high temperature resistance. DETAILED DESCRIPTION - Preparing high temperature resistant long-acting fluid loss reducing agent comprises (1) mixing graphene oxide with N-methylpyrrolidone in mass ratio of 1:150-1:200, carrying sealed ultrasonic dispersion to obtain graphene oxide dispersion, mixing graphene oxide dispersion with 4,4'-diaminodiphenyl ether in the mass ratio of 80:1-120:1, stirring the reaction under nitrogen atmosphere, filtering mixture under reduced pressure to obtain pre-modified graphene oxide, first washing the pre-modified graphene oxide with N-methylpyrrolidone for 2-5 times, washing with ethanol and water for 3-5 times, and drying to obtain modified graphene oxide; (2) orderly weighing 4-5 pts. wt. carboxymethyl cellulose, 10-12 pts. wt. chitosan acetic acid solution, 20-30 pts. wt. acrylamide, 10-14 pts. wt. 2-acrylamido-2-methylpropanesulfonic acid, 7-9 pts. wt. dimethyl diallyl ammonium chloride, 10-13 pts. wt. vinyl acetate, 5-8 pts. wt. initiator, and 200-300 pts. wt. water; mixing acrylamide with water, adding 2-acrylamido-2-methylpropanesulfonic acid, dimethyl diallyl ammonium chloride and vinyl acetate, stirring and mixing, adding carboxymethyl cellulose, chitosan acetic acid solution and initiator, stirring reaction under nitrogen atmosphere, adjusting the pH to 6.5-7.5, continuously stirring and reacting to obtain mixture, mixing the mixture with acetone in mass ratio of 1:2-1:3, filtering, drying in vacuum to obtain high temperature resistant long-term fluid loss reducing material blank; and (3) orderly weighing 40-60 pts. wt. high temperature resistant long-term fluid loss reducing material blank, 5-10 pts. wt. modified graphene oxide, 8-16 pts. wt. epoxidised soybean oil, 3-6 pts. wt. surfactant, 4-6 pts. wt. inorganic salt and 50-80 pts. wt. water; mixing the high temperature resistant long-term fluid loss reducing material blank with water, adding modified graphene oxide, epoxidised soybean oil, surfactant and inorganic salt, stirring and mixing.