| abstract |
The invention provides a preparation method of HPAA composite pH-responsive bentonite, comprising: (1) using citric acid as a modifier to perform primary modification on the bentonite; (2) mixing the primary modified mixture with a silane coupling agent Ultrasonic compounding is adopted; (3) the compounded mixture is centrifuged, washed and precipitated to be neutral, dried and pulverized to 500-800 nm to obtain activated bentonite; (4) the activated bentonite is mixed with α-cyanoacrylate, acrylic acid, methyl methacrylate Base acrylic acid, methyl methacrylate and 2-cyanoacrylic acid are subjected to in-situ copolymerization reaction, and after the reaction is completed, centrifugation, washing and drying are performed in sequence. The present invention also provides the application of the above-mentioned pH-responsive bentonite in the treatment of unconventional water-sensitive shale. The pH-responsive bentonite of the invention is equivalent to compounding HPAA molecules with bentonite, which not only ensures the basic plugging strength, but also enhances the flexibility of the bentonite particles, which is beneficial to embedding irregular nano-micron rock pores. |