Component A - a component containing polyether amines, which is responsible for the final physical and mechanical properties of the finished material.
Component B - acts as a hardener and regulates the reaction rate of the components.
Rostov polyurethane company offers 2 types of components for polyurea coatings:
RPC ARP (ST) - standard formulation.
RPC ARP (TV) is a reinforced formulation with increased strength characteristics.
An insulating layer of material is formed by metering two components in a predetermined proportion under pressure into a mixing gun for spraying, where, under the action of compressed air, highly efficient instant mixing of the components occurs. Then the mixture is sprayed onto the surface in the form of an aerosol torch.
The main advantages of polyurea are: speed of coating, isolation of complex contours and hard-to-reach places, solidity of the canvas, high physical and mechanical properties (Table 1), chemical resistance and durability of the coating.
Table 1. Physical and mechanical properties of polyurea coatings
| Relative elongation at break | 200-700% |
| Tensile strength at break | 10-30 MPa |
| Shore A hardness | 80-100 nominal units |
With a regulated time frame, the most effective solution is the use of polyurea. The term of insulation works with polyurea is several times shorter in comparison with alternative methods, since the material cures within the first six seconds after application. It should be noted that the complete polymerization of the coating takes place within a few days, but the main performance is obtained immediately after application.
Application technology
Before applying the polyurea coating, the first step is to prepare the surface. Carry out cleaning of all contaminants from the insulated surface, dedusting. Check the substrate for moisture content (permissible moisture content no more than 4%). If necessary, the surface is leveled with epoxy compounds, self-leveling floors and other polymers.
After surface preparation, a primer of the RPC Primer PU-ARP (1K) brand is applied to increase the adhesion of the polyurea coating to the base.
Next, polyurea is applied. Before application, it is necessary to warm up and mix component A, according to the recommendations in the technical conditions.
Aromatic polyurea coatings are not UV resistant. After spraying polyurea, it is necessary to apply a layer of light-resistant materials - spraying or coating membranes (polymer mastics), for example, light-resistant two-component RPC AM (2K) mastic.
- - Plate
- - Cement screed
- - Primer
- - Aromatic polyurea
- - Light resistant mastic
Figure 1. Typical polyurea waterproofing scheme.
Compliance with the stages of work and the manufacturer's requirements is mandatory.
A constructive solution made of insulating materials of the above sequence will form the most effective waterproofing layer on any structure for the planned period of operation.
Technical solutions
Polyurea coatings are used both at civil and industrial construction sites and for the isolation of more complex elements: tanks, engine compartments of ships, decorative items with asymmetrical contours, military equipment and other objects requiring a monolithic insulation coating.
A technical solution for insulation and waterproofing of roofs, foundations and underground technological tanks (containers) is the use of a construction "pie" made of polyurethane foam and polyurea.
For non-exploited roofs, polyurethane foam with a density of 30-50 kg/m3 is used;
for operated roofs and underground technological tanks - density of 60 kg/m3 or more, for foundations - from 40 kg/m3. The thickness of the insulation can vary from 25 to 100 mm, depending on the object and the operational purpose of the layer. Further, for waterproofing polyurethane foam, polyurea is applied in layers of 1 mm, the total thickness is 2-5 mm.
Finishing layer - light resistant mastic 0.3-0.5 mm.
Figure 2 shows a typical scheme for waterproofing an old roll (bitumen) roof with polyurea. When repairing flat roofs, polyurethane foam is applied over the old roofing material and other roll materials without complete dismantling. Only the exfoliated defective areas are preliminarily removed.
Figure 2. A typical scheme for waterproofing an old roll roof with polyurea.
