Talking about polymer waterproof coating for construction!

Nowadays, most building surfaces and roofs use metal materials.

Definition and classification of waterproof coatings

Waterproof coating is a viscous liquid polymer synthetic material.

Waterproof coatings can be divided into three types, namely solvent type, water emulsion type and reactive type

Waterproof coatings are generally divided into three layers in the coating.

Figure 1: The structure of the general roof waterproof layer

Figure 2: Examples of ingredients list for waterproof coating

Waterproof mechanism

The reaction mechanism of waterproof coating is divided into two kinds

Testing standards for coatings

Through the testing standards, we can know how the paint protects the inner metal roof

(1) Thermal aging treatment

Metal roof waterproof coating is directly sprayed or roller coated on the metal roof structure during the construction process.

Operation: Put the test piece horizontally in the electric heating blast drying oven, and take it out after being placed at a constant temperature

(2) Water immersion aging treatment

There is a certain amount of hydrophilic functional groups (-OH, -COOH) in the molecular structure of water-emulsifiable polymers, which determines that re-swelling by polar functional groups is inevitable when it is immersed in water for a long time

Operation: Under standard experimental conditions, soak the test piece in tertiary water for several hours and then take it out and wipe it dry with a dry cloth.

(3) Ultraviolet aging treatment

Because the light energy absorbed by the coating film under long-term ultraviolet irradiation is greater than the dissociation energy of the C—C bond in the polymer, the chain breaks inside the polymer, which reduces the flexibility of the coating film and the elongation at break

Operation: Sprinkle talcum powder on a 250 mm×250 mm glass plate, place the test piece horizontally on the glass plate, set the temperature of the ultraviolet aging box, and put the test piece in it for constant temperature irradiation

Concluding remarks

As a product widely used by polymers, waterproof coating has a rich market prospect and demand
.
In the future, waterproof coatings will change towards green and safe, reduce solvent-based products and increase reactive products, and improve product quality with better performance
.