Polyurea is truly a remarkable coatings, linings and joint sealant technology.
Polyurea is a type of elastomer that is derived from the reaction product of an isocyanate component and a synthetic resin blend component through step-growth polymerization. The isocyanate can be aromatic or aliphatic in nature. It can be monomer, polymer, or any variant reaction of isocyanates, quasi-prepolymer or a prepolymer. The prepolymer, or quasi-prepolymer, can be made of an amine-terminated polymer resin, or a hydroxyl-terminated polymer resin.
The resin blend may be made up of amine-terminated polymer resins, and/or amine-terminated chain extenders. The amine-terminated polymer resins will not have any intentional hydroxyl moieties. Any hydroxyls are the result of incomplete conversion to the amine-terminated polymer resins. The resin blend may also contain additives, or non-primary components. These additives may contain hydroxyls, such as pre-dispersed pigments in a polyol carrier. Normally, the resin blend will not contain a catalyst(s).
These are polyureas based on an aromatic diisocyanate (e.g. MDI, TDI,..). Their performance level is excellent, but these are not light-stable. This means the surface changes colour in sun light but does not degrade the physical properties.
These are polyureas based on an aliphatic diisocyanate (e.g. IPDI, HDI,…). They are light-stable, which means they don’t change colour when exposed to light (sun or artificial). Aliphatic systems are more difficult to process and generally cost twice as much as aromatic polyureas.
|PROPERTIES||AROMATIC POLYUREA||ALIPHATIC POLYUREA|
|Performance||Workhorse||Superior||Application||Base coat||Top coat||Colour Stability||Tends to chalk or darken in colour when exposed to UV||100% colour stable non yellowing exhibits good outdoor weathering||Finish||Matt||Glossy||Chemical Resistance||Excellent||Excellent||Waterproofing||Excellent||Excellent||Durability||Much better than other coatings||Even more durable||Minimum thickness||1.5 mm (60 mils)||0.75 mm (30 mils)|