Due to the specific layered structure of bentonite, it has a large specific surface area, so it has strong adsorption, and due to the presence of hydrophilic group OH-, it has excellent dispersion, suspension and adhesion in aqueous solution, and shows excellent thixotropy in a certain concentration range. That is, when there is external stirring, the suspension liquid appears as a sol with good fluidity, and after stopping stirring, it will arrange itself into a gel with a network structure without sedimentation and water separation. This property is particularly suitable for the formulation of drilling mud.Whether it is oil drilling or geological exploration drilling, a large number of bentonite is used as the main raw material to prepare drilling mud to protect the well wall, upward rock cuttings, cooling drill bits, etc. Bentonite is the most important natural mineral material used to adjust the rheology and filtration properties of drilling fluids. Bentonite, which is used as a drilling fluid material, is generally sodium-based bentonite, and calcium-based bentonite needs to be used after sodification. The organic modification of bentonite is generally to insert organic matter between montmorillonite layers and perform cation substitution between montmorillonite layers; At the same time, there are also many hydroxyl groups and active groups on the surface of montmorillonite particles and lateral fractures of crystals, which can be grafted and polymerized with alkene monomers under certain conditions. Its purpose is mainly to improve its adsorption and hydration, enhance the filter loss effect of bentonite and the synergistic ability with other treatment agents.