By Dr Stephan Göttke,a Dr Fikri Alemdaroglu,b Dr Werner Bertleff a,c
(a. BASF SE, b. Elastogran c. Corresponding author)
Polyurea systems have excellent performance and are therefore used in a broad variety of industrial applications. These include spray coatings that seal or cover roofs, pavement slabs for bridges, swimming pools, rail beds and tunnels.
Polyurea systems offer benefits in the segment of industrial flooring and sealants because, in contrast to other spray coatings, they may be applied in humid and low temperature conditions and cure fast. As curing takes just seconds, waiting times are clearly reduced, for example in rehabilitation projects, which helps to cut the overall cost.
Chemically speaking, polyurea elastomers are polymers formed by an isocyanate prepolymer reacting with diamines that act as curing agents. The striking features of polyurea elastomers include their ability to readily bridge cracks with an elastic coating and their superb adhesion to a wide variety of surfaces.
They are also exceptionally resistant to chemicals, high temperatures and mechanical strain. Their adhesion to different types of material is illustrated by coating applications on concrete, steel, polyurethane foam and wood.
Polyureas consist of defined hard and soft segments as they are known in polyurethanes, a related material. By selectively adjusting these segments, one can vary the properties of the polymer film over a broad range, from highly…