Abstract: Biomimetic nacre-toughness cement slurry based on in-situ polymerization of a fluid loss additive, a preparation method and an application thereof are provided. The preparation method includes: dissolving 2-acrylamido-2-methylpropane sulfonic acid monomer and carboxylic acid monomer in deionized water, adjusting pH to 5.5-6.5, then adding an acrylamide monomer, and uniformly stirring to obtain a monomer solution; adding an initiator and a catalyst into the monomer solution, and then stirring to obtain a pre-polymerization solution; adding cement particles into the pre-polymerization solution under low-speed stirring, and then performing high-speed stirring to obtain the biomimetic nacre-toughness cement slurry. The obtained cement slurry can optimize a microstructure of cement while possessing a well capacity for controlling fluid loss, improve deformation ability and toughness of a cement sheath, and effectively improve brittleness defect of the cement sheath.

Abstract: A water-adaptive cement self-healing system, a preparation method and an application thereof are provided. A pH-triggered shell curing agent, an inorganic nano-emulsifier, and a polysaccharide shell material are added into deionized water to obtain an aqueous phase; an active diluent of epoxy is added to an epoxy to obtain a first oil phase; the aqueous phase is mixed with the first oil phase to obtain an oil/water emulsion; a surfactant is added into paraffin oil to obtain a second oil phase; the second oil phase is mixed with the oil/water emulsion to obtain an oil/water/oil emulsion; an acidic liquid is added into the oil/water/oil emulsion dropwise to obtain a solid, followed by centrifuging, washing, and freeze-drying to obtain a self-healing capsule; and then an epoxy curing agent is mixed with the self-healing capsule to obtain the water-adaptive cement self-healing system based on an oil/water/oil double-emulsion template.

Abstract: The invention discloses an environment-friendly cement self-repairing system, and its preparation method and application. The preparation method comprises the following steps: adding a shell curing agent into deionized water to prepare solution 1, adding an inorganic nano emulsifier into deionized water, ultrasonically dispersing, then adding polysaccharide-shell, and uniformly stirring to obtain emulsion polymerization aqueous phase; adding epoxy diluent into epoxy resin, and uniformly stirring; obtaining an emulsion polymerization oil phase; mixing the emulsion polymerization aqueous phase and emulsion polymerization oil phase, and stirring to obtain uniform emulsion; dropping the uniform emulsion into solution drop by drop by using pendant drop method, stirring until the droplets are shaped, then filtering, washing with deionized water, and drying to obtain self-repairing capsules; next, mixing with an environment-friendly curing agent to obtain an environment-friendly cement self-repairing system.

Abstract: The invention discloses an environment-friendly cement self-repairing system, and its preparation method and application. The preparation method comprises the following steps: adding a shell curing agent into deionized water to prepare solution 1, adding an inorganic nano emulsifier into deionized water, ultrasonically dispersing, then adding polysaccharide-shell, and uniformly stirring to obtain emulsion polymerization aqueous phase; adding epoxy diluent into epoxy resin, and uniformly stirring; obtaining an emulsion polymerization oil phase; mixing the emulsion polymerization aqueous phase and emulsion polymerization oil phase, and stirring to obtain uniform emulsion; dropping the uniform emulsion into solution drop by drop by using pendant drop method, stirring until the droplets are shaped, then filtering, washing with deionized water, and drying to obtain self-repairing capsules; next, mixing with an environment-friendly curing agent to obtain an environment-friendly cement self-repairing system.