(Polycarbamides) - synthetic polymers containing fragments of urea-NH-CO-NH- in the main chain and generating from transamidation of urea by aliphatic diamines or polyamines or from copolymerization of diisocyanates with oligomeric di- or polyamines (hence this term does not apply to urea-formaldehyde resins synthesized from polycondensation of urea and formaldehyde). Structurally, polyureas are similar to polyurethanes synthesized by copolymerization of diisocyanates with poliolams and, like polyurethanes, are elastomers.
Polyurea is a coating which is resistant to corrosion and, at the same time, insulating against moisture. Polyurea is used in the construction of piers, flyovers, pipelines, tunnels, river and sea vessels, wharves, quays and bridges. For the same purposes, it is deposited on inner walls of oil and gas reservoirs.
This polymer laid on geotextile is used as a membrane seamless coating for terrestrial sumps and pits. The material is also used in construction of treatment and sewerage facilities.
The polymer is used in road construction for waterproofing works.
As being both corrosive and abrasive resistant material, polyurea is used in arrangement of parking spaces, protective coatings for cars, truck bodies, crushing and mining equipment, floor coverings.
Features of polyurea coatings
Polyurea composition determines its features:
- High strength and elasticity. Material tensile resistance is 38.5 MPa. This polymer is characterized by the highest abrasion resistance, far surpassing even the norms for floor tiles.
- The composition of the material does not include solvents. It is completely solid with 100% content of dry solid. That makes it possible for polyurea to meet the most stringent safety and environmental requirements.
- The highest rate of rejection of at least 10-20 seconds and a good reaction activity of the substance allows for spraying coatings in various conditions. In addition, any humidity does not matter but the temperature must be higher than -28 C. A base humidity may only affect the film adhesion, but not its quality at all.
- Polyurea forms a monolithic and seamless coating of a preset thickness, 0.4 mm per pass on average. Without any drips, the coating laying on the horizontal and vertical planes of any configuration.
- The deposited film solves the problems associated with protection from moisture, wear and corrosion.
- Excellent adhesion to almost all materials that are used in construction, excluding PTFE and Teflon.
- Good resistance when exposed to various chemicals.
- High fire safety: the material does not burn and distinguishes by its ability for self-extinguishing.
- A wide range of coating colors, allowing to use it as a decoration.
- Durability and good maintainability of the polymer film.