Bentonite is a type of clay mineral that is composed of aluminum phyllosilicates and other mineral compounds. Its unique physical and chemical properties make it an excellent choice for use in cement and mortar. When added to cement slurry, bentonite forms a stable colloidal suspension that helps to prevent settling and separation of the cement particles.
One of the key properties of bentonite is its ability to absorb and hold onto water molecules. This is known as its “swelling” capacity, and it is due to the presence of negatively charged ions on its surface that attract positively charged water molecules. This helps to reduce the amount of free water in the cement mixture, which in turn improves the workability and strength of the cement.
In addition to its swelling capacity, bentonite is also highly plastic and can be easily molded into various shapes. This makes it ideal for use in grouting and injection applications, where a stable and consistent mix is necessary.
When bentonite is added to cement slurry, it can also increase the diffusion degree in fine-grained alluvion. This means that the cement is able to penetrate small cracks and voids more effectively, reducing the risk of cement waste and ensuring a more homogeneous hardening process. As a result, the final product is stronger and more durable.
Finally, bentonite can also be used to repair cracks in walls and other structures by providing viscosity to cement slurry and increasing the diffusion of the slurry into the cracks. This helps to ensure a more effective and long-lasting repair. Overall, the unique properties of bentonite make it an important additive in the construction industry, helping to improve the strength, durability, and performance of cement and mortar.