Polyurea Industry Glossary

The polyurea coatings industry uses a specific set of technical terms that can be unfamiliar to newcomers and project owners alike. This glossary defines the key terminology used throughout our articles, training content, and industry resources. Terms are listed alphabetically for easy reference.

A

A-Side

In a two-component polyurea system, the A-side refers to the isocyanate component. It reacts with the B-side resin blend to form the polyurea elastomer. Proper heating and proportioning of the A-side is critical to achieving the correct chemical reaction and final coating properties.

Abrasion Resistance

A coating’s ability to withstand mechanical wear, scuffing, and friction. Polyurea is renowned for its high abrasion resistance, making it ideal for flooring, truck beds, and high-traffic industrial surfaces. See our complete guide to polyurea coatings for performance comparisons.

Adhesion

The bond strength between a coating and its substrate. Good adhesion requires appropriate surface preparation, primer selection, and correct application conditions. Poor adhesion is the most common cause of premature coating failure in the field.

Aliphatic Polyurea

A polyurea formulation using aliphatic isocyanates. Aliphatic systems offer superior UV stability and color retention compared to aromatic polyurea, making them preferred for exterior or aesthetically sensitive applications. They are typically more expensive than aromatic systems.

Aromatic Polyurea

A polyurea formulation using aromatic isocyanates. Aromatic polyureas offer excellent physical properties at lower cost but will amber or yellow when exposed to UV radiation, making them better suited for non-visible or overcoated applications.

B

B-Side

The resin blend component in a two-component polyurea system. Typically contains amine chain extenders and curatives that react with the isocyanate (A-side) to form the final polymer network.

Blast Profile

The surface roughness created by abrasive blasting on metal substrates, typically measured in mils. Achieving the correct blast profile ensures maximum mechanical adhesion for the polyurea coating.

Build (Film Build / DFT)

The thickness of the applied coating, typically measured in mils (thousandths of an inch) or microns. Polyurea systems are often applied at 80 to 250 mils depending on the application requirements.

C

Cathodic Disbondment

A type of coating failure common on buried or submerged steel where cathodic protection currents cause disbonding at the coating-metal interface. Polyurea pipeline coatings are formulated for superior resistance to cathodic disbondment. Related reading: polyurea pipeline coatings.

Chain Extender

A short-chain diol or diamine that reacts with the isocyanate to extend the polymer chain, modifying the final coating’s hardness, flexibility, and chemical resistance profile.

Cure Time

The time required for a polyurea coating to reach its final physical properties. Pure polyurea systems can achieve tack-free cure in seconds and full mechanical cure within minutes, one of their key advantages over epoxy and urethane systems.

D

Dew Point

The temperature at which moisture begins to condense on a surface. Applying polyurea to substrates at or below the dew point can cause adhesion failure. Contractors typically require substrate temperatures to be at least 5°F above the dew point before application.

Dunnage Coating

A protective coating applied to cargo-carrying surfaces such as trailer floors, railcar beds, and shipping container floors. Read more: the role of dunnage coatings in cargo protection.

E

Elastomer

A polymer with elastic properties, capable of significant deformation under stress and recovery to its original shape. Polyurea is classified as an elastomeric coating, which gives it flexibility advantages over rigid coatings like epoxy.

Elongation

The percentage a coating can stretch before breaking. High elongation is critical in applications where substrate movement or cracking is expected. Quality polyurea formulations typically achieve elongation values of 200 to 500 percent.

G

Gel Time

The time from initial mixing to when the material starts to gel and become unworkable. Polyurea gel times can range from a few seconds to several minutes depending on formulation and temperature.

H

Hybrid Polyurea

A coating that combines polyurea chemistry with polyurethane components, typically offering a slower cure time for easier application while retaining many performance advantages of pure polyurea. Hybrids are often used where the extreme speed of pure polyurea is not required.

Hydrophobic

Water-repelling. A critical property of cured polyurea coatings that makes them effective moisture barriers in underground and immersion applications.

I

Isocyanate

The A-side reactive chemical component in polyurea and polyurethane systems. Isocyanates react with amines (in polyurea) or alcohols (in polyurethane) to form the polymer network. Common isocyanates include MDI (methylene diphenyl diisocyanate) and HDI (hexamethylene diisocyanate).

M

Mils

A unit of measurement equal to one-thousandth of an inch (0.001″). Coating thickness in the polyurea industry is almost universally measured in mils. A typical protective polyurea application might specify 80 to 120 mils of dry film thickness.

MDI (Methylene Diphenyl Diisocyanate)

The most commonly used aromatic isocyanate in commercial polyurea systems. MDI-based systems offer excellent physical properties at competitive cost and are widely used in infrastructure, pipeline, and industrial applications.

P

Plural-Component Equipment

Spray equipment that heats, proportions, and mixes two separate chemical components at high pressure. Essential for applying commercial polyurea coatings. Leading manufacturers include Graco, Gusmer, and GlasCraft.

Pot Life

The amount of time a mixed coating remains usable after the components are combined. In pure polyurea, the pot life is near zero, meaning materials must be mixed at the gun tip during spray application.

Primer

A preparatory coating applied to a substrate before the polyurea topcoat. Primers improve adhesion, seal porous substrates, and prevent moisture vapor transmission that could cause delamination.

S

Shore A Hardness

A standardized measure of the hardness of elastic materials. Polyurea formulations range from soft (Shore A 40 to 60) for flexible membranes to harder (Shore A 90 and above) for abrasion-resistant coatings.

SSPC Standards

Standards from the Society for Protective Coatings (now part of AMPP) that specify surface preparation requirements for steel substrates. SSPC-SP6 (commercial blast) and SSPC-SP10 (near-white blast) are commonly required before polyurea application on steel.

Substrate

The surface to which a coating is applied. Common polyurea substrates include carbon steel, stainless steel, concrete, foam, wood, and geotextiles.

T

Tensile Strength

The maximum stress a coating can withstand before breaking, measured in pounds per square inch (psi). Commercial polyurea systems typically achieve tensile strengths of 2,000 to 4,000 psi.

Topcoat

The final coating layer applied over a primer or basecoat. In polyurea systems, aliphatic polyurea or polyurethane topcoats are often applied over aromatic polyurea basecoats to improve UV resistance and color stability.

U

UV Stability

A coating’s resistance to degradation from ultraviolet radiation. Aromatic polyurea systems have poor UV stability and will chalk and yellow in direct sunlight. Aliphatic polyurea topcoats offer superior UV resistance for exterior applications.

V

VOC (Volatile Organic Compound)

Organic chemicals that vaporize at room temperature. Polyurea coatings are typically 100 percent solids systems with zero or near-zero VOC content, making them environmentally preferable to solvent-based coatings and compliant with strict air quality regulations.

For more information about any of these terms in context, explore our Education section, our Polyurea FAQ, or browse our full articles archive. If you have additional terms you’d like to see defined, contact us.