Bentonite waterproof blanket is a kind of geosynthetic material specially used for anti-seepage of artificial lake waterscape, landfill, underground garage, roof garden, pool, oil depot and chemical storage yard. The sodium-based bentonite is filled between the special composite geotextile and non-woven fabric. The bentonite impermeable pad made by acupuncture method can form many small fiber spaces. The bentonite particles cannot flow in one direction, and will be in the pad when it encounters water. Form a uniform high-density colloidal waterproof layer to effectively prevent water leakage.

The mineralogical name of bentonite is montmorillonite, and natural bentonite is mainly divided into two categories: sodium-based and calcium-based according to its chemical composition. Bentonite has the property of swelling in contact with water. Generally, when calcium-based bentonite expands, its expansion is only about 3 times its own volume, while sodium-based bentonite absorbs five times its own weight of water when it encounters water, and its volume expands to 15-17 times the original volume. Above, the sodium bentonite is locked in the middle of two layers of geosynthetics, which plays the role of protection and reinforcement, so that GCL has a certain overall shear strength.

According to the production process, bentonite waterproof blanket can be divided into:

Acupuncture sodium bentonite waterproof blanket, acupuncture lamination sodium bentonite waterproof blanket and adhesive sodium bentonite waterproof blanket.​​

The needle-punched membrane-covered sodium-based bentonite waterproof blanket is a high-density polyethylene geomembrane compounded on the outer surface of the non-woven geotextile of the needle-punched sodium-based bentonite waterproof blanket.

Adhesive sodium bentonite waterproof blanket is a kind of sodium bentonite produced by compressing bentonite particles to high-density polyethylene board with adhesive.