Product description
Polyurea is a two-component sprayable polymer coating obtained through the reaction of a polyamine hardener, which is component A, with a copolymer based on isocyanate, which is component B.
Features of the Polyurea Coating:
- High strength, hardness, and absence of seams.
- Ability to be applied to surfaces of any shape and size.
- The material gains strength several hours after application.
- Resistance to water and weak salt solutions.
- Resistance to short-term exposure to motor oil and diesel fuel.
Physical and mechanical parameters
Table 1 — Characteristics of Mixture Components
|
Parameter
|
Value
|
|
Component
|
Component А
|
Component B
|
|
Appearance
|
Homogeneous liquid or suspension
|
Homogeneous liquid from light yellow to dark brown in color
|
|
Apparent viscosity according to Brookfield at 25°C, mPa·s
|
500-700
|
800-1000
|
|
Density at 20°С, g/cm3
|
0.97-1.04
|
1.10-1.16
|
Table 2 — Finished Coating
|
Parameter
|
Value
|
|
Appearance
|
Homogeneous solid materia
|
|
Primary curing time at 20°C, min
|
2
|
|
Tensile strength
|
18–20 MPa
|
|
Elongation at break
|
45–50 %
|
|
Water absorption within 24 hours
|
Not more than 2% by mass
|
|
Shore A hardness
|
92–98
|
Hygienic Characteristics
After drying, the coating does not have a negative impact on human health and the environment.
The suspended particles of the components of polyurethane can cause irritation when they come into contact with the mucous membranes of the eyes, upper respiratory tract, and skin.
Other Characteristics
Component Ratio:
Component A: 100 parts by volume.
Component B: 100 parts by volume.
Preparation for Work
Requirements for Component Preparation
Component A should be thoroughly mixed for 30 minutes before use at a mixer speed of 200 rpm.
Component B should be thoroughly mixed for 30 minutes before use at a mixer speed of 200 rpm.
Requirements for Application Conditions
The ambient temperature should not be lower than +5°C.
Surface Preparation Requirements
The surface temperature should be 3°C above the dew point.
Preparation of Foam Board
Clean the surface, remove dust, degrease it by wiping with alcohol-soaked cloth, dry it, and remove dust again.
Safety Measures
Do not work near open flames.
Use personal protective equipment: special clothing, gloves, footwear, and a full-face gas and dust respirator.
If it comes into contact with the skin, remove the product with a cotton pad or cloth, rinse with warm soapy water, and seek medical attention if irritation persists.
If it comes into contact with the eyes, immediately rinse them with a large amount of water for at least 15 minutes. Seek medical attention if irritation occurs.
Rules for Processing/Application
Component systems are applied using high-pressure installations.
The temperature of the components is 50-70°C. The pressure in the hoses delivering components A and B to the mixing chamber is 150-250 bar, and the temperature in the hoses is 60-80°C.
Before spraying the components, check the condition of the equipment. In case of contamination of the mixing chamber and the nozzle of the spray gun, clean them.
For better mixing of components, the temperature and pressure of delivery are adjusted during the spraying process depending on the equipment and the performance of the spraying gun.
Before applying the base layer, it is recommended to apply a preliminary layer with a thickness of about 0.5 mm and wait for 5 minutes. This will protect the base layer from defects that may occur due to temperature differences in the polyurethane near the base and in other parts of the layer.
The recommended application thickness is 2 mm.
Recommended equipment for applying Chemtrast PM for sculptures:
- Graco Reactor 2 E-XP2, Graco Reactor 2 H-XP2, Graco Reactor 3 E-XP1, Graco Reactor 3 E-XP2, Graco Reactor 2 H-XP3;
- Gama EVOLUTION G-250H, Gama EVOLUTION G-35H, Gama EVOLUTION G-50H.
Attention!
Do not use polyurethane on spraying equipment without adjustable hose heating.
Problems and Their Solutions
Problem: Formation of bubbles between the base and the polyurethane layer within 1-2 days after the application of polyurethane.
Most likely causes:
- Residual moisture on the base due to inadequate surface preparation.
- Residues of components from previously used high-pressure spray polyurethane in the equipment.
- Disruption in the ratio of components A and B.
- Moisture in the air from the compressor — malfunction of the dryer.
Solution: Treat the previous layer with sandpaper with a grit size of 40-60 to create a rough surface, remove dust, degrease by wiping with a cloth soaked in alcohol, dry it, and remove dust again.
Transportation and Storage Conditions
Polyurethane components should be transported by all means of transportation in closed vehicles in accordance with the cargo transportation rules applicable to each type of transport, ensuring the integrity of the packaging, its secure fixation to prevent damage and leakage.
Store them in closed storage facilities in the original sealed packaging, in conditions that prevent moisture ingress.
Storage temperature: from +10°C to +30°C.
The warranty storage period, when recommended conditions are followed, is 6 months from the date of manufacture.
After the storage period expires, the polyurethane components should be checked for compliance with technical specifications, and if their suitability is confirmed, they can be used as intended.
