Difference between polyurethane coating and polyurea coating

As we all know, polyurethane is a widely used polymer material on the market, which can be used as adhesives, sealants, coatings, insulating materials, fillers, foaming materials, engineering plastics, rubber products, fibers and so on.

And polyurea waterproof coating has gradually become familiar to people in recent years. Is there any similarity between polyurea waterproof coating and polyurethane waterproof coating? Is there any difference? Let's see.

Polyurethane is a polymer material formed by the chemical reaction between isocyanate compounds and polyhydroxy compounds to form polyurethane bonds. Polyurea is a urea-bonded polymer formed by the reaction of a polyisocyanate with a polyamine.

The similarities between the two are:Polyurethane cures to a film and polyurea cures to a film with the same or similar types of chemical bonds contained in the molecular chains. Polyurethanes or polyureas must first be made into prepolymers or semi-prepolymers or oligomers with isocyanate end groups.

They differ in that the functional group that plays a key role in the physical properties of the polyurethane film is the urethane bond, while the functional group that plays a key role in the properties of the cured polyurethane is the urea bond. The urea bond bond strength is much greater than the urethane bond strength, and the urea bond is very stable, which is more advantageous to see polyurea.

How to apply polyurethane and polyurea?

Compared to brush and roller coating, polyurethane and polyurea sprayers do not need to be dipped into the material during on-site construction, so there will be no dripping phenomenon, avoiding waste of material; and even more different from traditional air spraying is that the polyurethane spraying is atomized paint rather than atomized air, so it will not lead to the dispersion of the paint to pollute the environment and cause waste. What is even more different from traditional air spraying is that airless spraying is atomized paint rather than atomized air, so it will not cause the paint to fly around and pollute the environment and cause waste. Moreover, it is easy to clean, the air and water self-cleaning system solves the problem of cleaning the gun head of the previous foaming machine.

Polyurea spraying machine is actually a kind of spraying method, this equipment has four major properties, such as adjustable range, superior wear resistance, wide applicability, good sound transmission, strong adhesion and other properties.