Maybe you have used polyurea, but still complicated with what exactly polyurea is, this article will give you a brief introduction about polyurea  technology.

The overview of polyurea.

Polyurea is an advanced coating technology, it is an elastomer that formed by the reaction of isocyanate (A part) and synthetic resin blend component (B part).

Based on the different varieties of the isocyanate and resin that exist, we can produce different variations of polyurea, hybrid and polyurethane.

This can affect its gel time, physical property, hardness, flexibility, durability, impact resistance, and many other properties among other special qualities.

What is difference between pure polyurea and hybrid?

The main difference between pure polyurea and hybrid is in the B side, Pure polyurea use amine terminated polyether, which has good reaction activity, and don’t need catalyst.

The B side of hybrid polyurea is hydroxypolyether, the reaction activity is lower so it’s not stable when the humidity is very high.

While the pure polyurea is much stable in different environment moisture. But chemist can add additive and catalyst to modify hybrid.

However, pure polyurea also has disadvantages, its raw material range is relatively small, so if you need special properties, such as high hardness or super longer gel time, we can only be used "hybrid" or polyurethane.

While the pure polyurea is much stable in different environment moisture. But chemist can add additive and catalyst to modify hybrid, so it’ s much important to choose the suitable formulation to your project.

What is aromatic polyurea and aliphatic polyurea?

The most formulations we used now is aromatic polyurea, because the aliphatic is much expensive.

Aromatic polyurea use aromatic isocyanate and aromatic resin, and in that case, the chemical structure of aromatic polyurea has a benzene ring, which caused the yellowing after exposure to the UV.

While aliphatic polyurea use aliphatic isocyanate and aromatic resin, it’s color stable under UV exposure.

The disadvantage is that it’s expensive compare the Aromatic. Aromatic polyurea can meet the general waterproof and anticorrosive requirements, so it's more widely used.

What is hand applied polyurea?

Spray polyurea has many advantages, but it's not convenient for some small area, so the chemist has developed manual polyurea, which can be applied by brush or scraper.

There is also aromatic hand applied polyurea and aliphatic hand applied polyurea, and according to the reaction method, there is single component hand applied polyurea and two components hand applied polyurea, to meet the different needs of customers.

Different types of polyurea

So, the types of polyurea showed as follows.

What are the main Features of spray Polyurea？

In recent years, polyurea technology has been developed rapidly and widely both in China and all over the world. Because it’s super physical properties and durability, and the most important is that it’s an environment friendly material.

We know that there are many different types and different formulations of polyurea, and different formulations of polyurea have different characteristics. But the main characteristics of spray polyurea are:

1. Fast cure; can spray on vertical surface without sagging.

2. 100% solid content, no solvent, non-toxic, friendly to environment.

3. Insensitive to water and moisture, good water proofing and anticorrosion property.

4. It can achieve the required thickness at one time, highly efficient.

5. Excellent physical properties, such as tensile strength, flexibility, durability, abrasion resistance, chemical resistance, etc.

6. High thermal stability, can use under 100℃ for long time and withstand 180 ℃ short-term thermal shock.

7. Formula is adjustable, and the feeling is from soft rubber (shore A30) to hard elastomer (shore D80).

8. Use complete spraying and casting equipment, high efficiency.

What is the durability about polyurea?

Here is the saying that "three points material, seven points construction", which indicating the importance of materials and construction in polyurea application, so we can know that both material and construction has influence on the durability of polyurea project.

From the perspective of materials, compared with traditional waterproof materials, the chemical structure of polyurea is indeed more stable, and according to the acceleration experiment, polyurea has good durability than asphalt, epoxy, polyethene or rubbers.

And in order to achieve a durable polyurea project, we should also pay attention to the application details.

So that if we choose the right formulation of polyurea and use the correct construction method, it can achieve a super longer service life than ordinary waterproof materials, maybe over 20 or 30 years.

What is the application method of Polyurea?

It’s differed from which kind of polyurea do you use.

For spray polyurea, we sprayed with plural component spray equipment, which has high temperature and high pressure, because it’s cured very fast.

High temperature can reduce the viscosity of the isocyanate and resin part, high pressure can make the two components collide quickly at the chamber of the gun and spray out quickly.

There is also cold applied polyurea, which has longer gel time, can be sprayed by low pressure cartridge gun.

For single component and two components polyurea, it can be applied by hand, which is suitable for small area application, or where there is no electricity.

What is the suggest thickness of polyurea?

Spraying polyurea is a solvent-free material, so it can be thickly coated, One time spraying can achieve the design thickness.

Generally, we suggest that the thickness of polyurea on the surface of concrete should be more than 2.0mm.

The recommended thickness of polyurea spraying on metal better greater than 1. 5mm. Because concrete is a porous structure and has many defects like pinholes on the surface. Some defects may not be covered if the coatings are too thin, and it might cause defects.

When spray polyurea, we should spray the corners and welding joints first, and the flat surface second, in case to confirm the thickness of polyurea is enough in weak area.

In fact, as the inventor of polyurea, Mr. Dudley Said, “polyurea is kind of technology but not a simple material”.

There are many things need us to research, and many details during the application we should pay attention to, but it has very bright prospects, we will keep promoting this technology, to provide more solutions to our customers.