FREQUENT APPLICATIONS

Polyurea has a very low water permeability, which makes it an ideal resin for moisture barrier applications. The most critical applications are industrial spray coatings and elastomers used in harsh environments, including exposure to hydrocarbons, saltwater, bases, and diluted acids, fuels, fuel oils, and hydrogen sulfide. However, long-term exposure to these chemicals can affect performance and durability, so they must first be tested.

WHAT WE MUST DEMAND A POLYUREA

With the urea bond, we achieve that from the molecular structure, a moisture insensitivity is generated, which makes Polyurea (as long as it is pure) one of the best waterproof membranes.

We say "whenever it is pure" because, in the market, there are numerous Polyureas of the so-called "hybrids", which are a mixture between polyurethane and Polyurea. These membranes do not have the same mechanical properties as pure Polyurea (highlighting their excellent elongation and abrasion resistance); the difference shown in the following relationship:

Polyurea (pure) = polyamide + isocyanate

Polyurethane = isocyanate + polyol + catalyst

Polyurea (hybrid) = polyamide + isocyanate + polyol

Elastomeric Polyurea systems formulated only with polyamides and isocyanate are incredibly reactive, resulting in a 100 percent pure polyurea. Now so that the reactions carried out under the most optimal conditions, the isocyanate is added with a catalyst additive, which regulates the response and curing time, being able to achieve concise reaction and curing times, from 3 to 6 seconds. What is genuinely advantageous is that the proportions of the catalyst additive can be adjusted, to obtain the most appropriate reaction and cure times depending on the conditions required for each application and finish requested, the activator or catalyst additive used is DETDA80.

PURE POLYUREA, AROMATIC OR ALPHATIC?

Polyurea, depending on its chemical structure, can be of two types: aliphatic or aromatic. The aromatic is more tenacious than the aliphatic. Still, it does not resist exposure to ultraviolet (UV) rays, which causes discoloration and loss of brightness, which does not make it advisable for “face view” applications.

Aliphatic polyurea, on the contrary, is more resistant to UV radiation, so it is significantly better as a topcoat, but its production cost is higher since the raw materials needed to manufacture it have a higher price.

POLYUREA REQUIREMENTS

Polyurea is a very prominent technology with a range of uses whose limit is imagination. As with other coating systems and, if possible, Polyurea is even more demanding, adequate surface preparation, a human and technical team specialized in its correct application are required, and the use of specific base primers is required compatible.

IN-SITU MANUFACTURING OF THE POLYUREA

A product system to manufacture the polyurea requires precise temperature and pressure conditions, so two-component hot projection equipment needed that must operate at high pressure to produce the polyurea in a chemical gun-tip reactor. Therefore, hardware capable of supplying strains in the environment of 19 MPascal and high temperatures above 70 ºC is necessary.

Today there is technology available to produce polyurea outside a traditional factory. Advanced technology manages by remote software, which allows the manufacture of polyurea on-site. Supported by advanced control modules that automatically collect data from work registration and manufacturing parameters, allowing to confirm that the work Manufacturing has been carried out according to the specifications, allowing a more precise adjustment of costs and forecasts.