Polyurethane Waterproofing

Polyurethane waterproofing is a waterproof coating material with polyurethane prepolymer as the main component, which is cured by chemical reaction to form a high elasticity, high strength and excellent bonding performance. It is applied in liquid form and can form a seamless overall waterproof layer in complex structures or special-shaped parts. It is suitable for waterproofing and moisture-proofing of various building structures. Polyurethane waterproofing materials are divided into two types: single-component and two-component. Single-component materials directly react with moisture in the air to cure, while two-component materials need to be mixed in proportion before construction, with faster curing speed and more stable performance. Polyurethane waterproof coating has excellent elongation, crack resistance and weather resistance. It can adapt to the slight deformation of the base layer and prevent cracking and leakage caused by temperature changes. At the same time, it has good water resistance, chemical corrosion resistance and UV resistance. It is suitable for waterproofing projects in roofs, basements, toilets, swimming pools, bridges and other parts. It is easy to apply by brushing, spraying or scraping to form a continuous, seamless, and highly adhesive waterproof membrane that can effectively block water penetration. In addition, polyurethane waterproof coatings have good environmental performance, and some products have reached low VOC emission standards, which are suitable for occasions with high environmental protection requirements. During the construction process, attention should be paid to the base treatment to ensure that the surface is dry, flat, dust-free and oil-free to ensure the adhesion and waterproof effect of the coating. During use, the construction thickness needs to be controlled, and it is usually necessary to apply it in multiple times to achieve the best waterproof effect. Polyurethane waterproof coatings have strong durability and long service life. They can maintain good waterproof performance for a long time and can still maintain stable physical properties in humid environments or long-term immersion.

Advantages

The whole is seamless and has excellent waterproof performance. Polyurethane waterproof coatings can form a continuous and seamless waterproof layer that can completely cover complex structures and special-shaped parts

Excellent elasticity and ductility, so that the waterproof layer can effectively adapt to slight deformation or cracking of the base

It has good water resistance, can resist the erosion of rainwater and groundwater for a long time, and has strong acid and alkali resistance and corrosion resistance

The construction method is flexible, and brushing, spraying or scraping can be used. It is suitable for large-scale construction and maintenance projects, with a short construction period, easy operation, and reduced construction costs.

It complies with environmental protection standards, has low VOC emissions, is non-toxic and odorless, is safe to construct, and has little impact on the human body and the environment. It has excellent high and low temperature resistance, can maintain stable physical properties in cold and high temperature environments, will not crack or fail due to temperature changes, has a service life of more than 10 years, and is cost-effective.

Work Suggestions

According to the type of polyurethane waterproof coating selected, make the correct material ratio and stirring:

Single-component coating: After opening the barrel, stir it thoroughly and it can be used directly.

Two-component coating: Mix components A and B according to the ratio provided by the manufacturer, use a low-speed stirrer to stir for 3-5 minutes to ensure that there is no precipitation and no bubbles. After stirring, it should be used up within the specified time to prevent curing from affecting construction.

Construction can be done by brushing, rolling, spraying or scraping

First, do local reinforcement treatment on the corners, pipe roots and other parts to ensure that these leak-prone parts have sufficient thickness.

Divide into multiple layers, each layer has a coating thickness of 0.5-1.0mm, and the next layer is applied after the previous layer is dry (usually 6-12 hours) to avoid too thick a coating affecting the curing effect.

The brushing direction of each layer should be perpendicular to each other to ensure uniform coverage and avoid missing coating.

The coating thickness of conventional waterproofing projects should reach 1.5-2.0mm, and the thickness of projects with higher requirements such as underground waterproofing should reach 2.5-3.0mm.

When increasing the coating thickness, multiple coats should be applied to avoid excessive coating thickness causing sagging or incomplete curing.

Transportation And Storage

Avoid violent collisions, heavy pressure and dumping during transportation to prevent packaging damage or coating leakage.

Avoid long-term exposure to high temperatures or direct sunlight to prevent the coating from prematurely curing or deteriorating due to increased temperature.

During transportation, keep away from fire, heat sources and flammable items to prevent accidental combustion or explosion.

During winter transportation, insulation measures should be taken to prevent the viscosity of the coating from increasing or freezing due to low temperatures, which will affect the construction performance.

Polyurethane waterproof coatings should be stored in a cool, dry and well-ventilated indoor environment, avoiding direct sunlight and rain. The storage temperature should be between **5℃-35℃**.

Keep away from fire and heat sources. Smoking or using open flames in the storage area is strictly prohibited to prevent fire accidents.

The shelf life of polyurethane waterproof coatings is generally 6-12 months. During storage, the coating condition should be checked regularly to ensure that it is used within the shelf life to avoid performance degradation due to overdue.