▎ 摘　　要

NOVELTY - Plugging type fluid loss agent comprises 8-12 pts. wt. oxidized graphene, 20-35 pts. wt. concavo-convex rod-shaped stone, 0.5-0.8 pts. wt. initiator, 2-3 pts. wt. silane coupling agent, 4-6 pts. wt. cross-linking agent, 58-90 pts. wt. matrix asphalt and 12-18 pts. wt. aggregate monomer. The aggregate monomer is synthesized by acrylamide, acrylic acid and 2-Acrylamido-2-methylpropane sulfonic acid, where the weight ratio of acrylamide, acrylic acid and 2-acrylamide-2-methylpropanesulfonic acid is 4:1: 18. USE - Plugging type fluid loss agent for oil-based drilling fluid. ADVANTAGE - The plugging type fluid loss agent not only reduces the cost, but also increases the temperature resistance of the polymer resin At the same time, it has good compatibility with drilling fluid, has strong plugging ability, and can form effective plugging in a short time to prevent further intrusion of filtrate. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing plugging type fluid loss agent, which involves uniformly mixing the prescription amount of concave-convex rod-shaped stone and calcium chloride solution to form dispersion liquid, standing for 5h to 6h, mixing acrylamide, acrylic acid and 2-Acrylamido-2-methylpropane sulfonic acid, adding calcium chloride solution, stirring until it is colourless transparent solution, heating the matrix asphalt to dissolve, keeping the temperature at 180-240℃, adding graphene oxide and stirring uniformly to obtain the oxidized graphene modified asphalt, injecting the dispersion liquid and the graphene modified asphalt into the transparent solution, then adding silane coupling agent, crosslinking agent and initiator, stirring uniformly to form mixed solution, performing ultrasonic dispersion for 10 minutes, injecting the ultrasonic dispersed mixed liquid into the reaction kettle, then magnetically stirring the reaction kettle, at the same time, heating the reaction kettle, until the reaction temperature is reached, transferring the reaction kettle to constant temperature water bath container to continue reaction, after finishing the reaction, taking out the product, and washing the surface, grinding and dispersing the polymer, then putting in 90℃ drying box for drying for 9 hours, uniformly mixing the dried polymer powder with white oil.