Advantages and construction methods of polyurethane sealant

Polyurethane sealant (PU sealant for short) is an elastomer mixed with polyether polyol and polyisocyanate as the main raw materials, supplemented by fillers, plasticizers, coupling agents, and catalysts. Depending on the application location, the one-component polyurethane caulking adhesive produced by our company can be divided into two types: thixotropic type and self-leveling type.

This product is suitable for expansion joints of high-speed railway ballastless track bottom plates and joints between base/support layers and offline structures. It can also be used for expansion and contraction of building components such as urban subways, highways, airports, nuclear wind and hydropower stations, urban comprehensive pipe corridors, and cement roadbeds. seams and structural seams.

Advantages of this product:

1. Single component, easy to construct, no need for weighing, proportioning or stirring, it can be used immediately.

2. There will be no expansion joints on the base surface under high temperature or humidity.

3. The surface drying time is fast, and the curing after surface drying is not affected by wind and rain. It is suitable for rainy, windy and other severe weather.

4. Good storage stability, which is beneficial to the storage and transportation of products.

5. It has good adhesion to cement and metal materials, and forms a strong bonding force with the seam ends, which can prevent the sealant from falling off and reduce maintenance costs.

6. It has excellent high and low temperature resistance and alkali resistance, and can adapt to the actual working conditions of hot extrusion and cold drawing.

7. The same materials are firmly bonded to facilitate secondary construction or maintenance.

Construction method of polyurethane sealant

1. Remove excess concrete in the expansion joints, as well as excess foam plastics, debris, gravel, etc. in the joints, and then use a broom and hair dryer to blow away the debris and dust in the expansion joints and nearby concrete to ensure Clean and dry the expansion joints.

2. Select a suitable foam lining and place it into the expansion joint. The width of the foam lining should be greater than the width of the gap to maintain sufficient support and ensure the molding standard of the sealing material after drying.

3. After the installation of the lining strip is completed, use tape to cover the board surface around the seam to prevent the caulking sealant from contaminating the board surface during the construction process.

4. After the protection is completed, apply the interface agent on the inside of the expansion joint. The coating should be even and the thickness of the coating layer should be moderate.

5. After the interface agent is dry, slowly drive the caulking material into the expansion joint with a sealant gun, and then smooth the surface with a spatula.