Polyureas are a group of polyurea chemical compounds which are derived from polyurea-producing algae. Polyurea itself is an elastomeric substance obtained from the sap of a polyurea tree through chemical synthesis. Polyurea and its chemical derivatives have applications in a wide variety of industries, including cosmetics, pharmaceuticals, energy, rubber, plastics, dry cell technology, nanotechnology and biotechnology. Polyureas are used as lubricants and lubrication oils, and as additives for a range of processes, including drying, heating, deicing, lubricating, sealing, and grinding. Polyureas have also been developed to act as antioxidants and as growth hormones.
Polyureas are a unique class of materials which have the ability to diffuse moisture, thereby acting as a thermosetting surface barrier. In its simplest form, polyurea dries by forming a thin, brittle film. This film is often referred to as a stress-relief layer, because it relieves internal stresses by allowing water to diffuse into a liquid medium, or to evaporate slowly. Polyureas have numerous physical and chemical properties which make them useful in a wide range of applications.
Polyurea coatings have a wide range of applications where both moisture resistance and protection against heat are important. Polyurethane coatings are most commonly used as barriers in petroleum refractory situations. They are also used on structures to reinforce structural bracing for thermal and corrosive resistance. Structural coatings based on polyurethane have been successfully used in numerous applications, including: building foundations, bridge coatings, roofing and roof deck coatings, structural dentistry, dental implants, industrial floor coatings, and industrial lubricants. Some polyurethane coatings also serve as antimicrobial coatings to inhibit growth of mould and mildew.
Polyurea products are available in numerous shapes, colors, and textures, depending on the application. As an adhesive, polyurea allows for a range of flexibility in design and the ability to form complex and intricate sealants. For example, a polyurea layer can be used as a rapid drying medium for high performance tools. Further, some polyureas offer elongation, impact resistance, chemical resistance, and anti-static properties, which make them ideal for applications requiring protection against chemicals, electricity, and fire.
Polyurea can also be combined with other polyurethane coatings for extra abrasion protection and/or moisture management. When combined with polyurethane and lamination, the result is an effective barrier that can withstand high impact loads without breaking or tearing. The combination of polyurea and lamination coatings are most common for resisting impact and corrosion. Many marine applications use this technology in their applications because of its inherent effectiveness and resistance to abrasion and heat. The unique combination of polyurea and lamination coatings offers a combination of protection and durability that cannot be found in other synthetic membranes.
Hybrid coatings have the advantages of the pure polyurea with a host of polyurethane characteristics that enhance its overall properties. These hybrids include thermal stability, dimensional stability, protection against abrasion and heat, and anti-corrosion and wear resistance. Most hybrid coatings are formulated with a host polyurethane that has the physical properties needed to perform as an effective barrier, while providing a solution for moisture management and its accompanying cost savings.
