Polyurea

In a polyurea, alternating monomer units of isocyanates and amines react with each other to form urea linkages.

This acid quickly decomposes by splitting off carbon dioxide and leaving behind an amine.

[4] Its fast reactivity and relative moisture insensitivity made it useful for coatings on large surface area projects, such as secondary containment, manhole and tunnel coatings, tank liners, and truck bed liners.

Excellent adhesion to concrete and steel is obtained with the proper primer and surface treatment.

[5] Some polyureas reach strengths of 40 MPa (6000 psi) tensile and over 500% elongation making it a tough coating.

The high strength, impact and abrasion resistance of polyurea coatings is a key reason for their use.

Elastic, self-healing paints and other coatings recently took a step closer to common use, thanks to research being conducted at the University of Illinois.

Scientists there have used "off-the-shelf" components to create a polymer that melds back together after being cut in half, without the addition of other chemicals.