Pushing boundaries: Lifting polyurethane chemistry into the next dimension

 
Polyurethane (PU) coatings are nowadays state-of-the art technologies in a wide range of different applications. To adjust material's properties, structurally different polyols and polyisocyanates are typically employed; this strategy has been and still is pursued with great success. However, some features of the PU coating are limited by thermal stability of the urethane group and by the maximum intrinsic network density that can be achieved in conjunction with polyols. Isocyanurate crosslinking moieties - so called cyclic isocyanate trimers -, on the other hand, greatly increase thermal stability and network density of a PU coating. These desirable properties are governed by the chemical nature of the isocyanurate ring and determine the resulting macroscopic properties. Here, we will describe new polyisocyanurate-based coatings that can be obtained by well-designed and controlled trimerization of isocyanate groups. The astonishing coating properties, which can be harvested from isocyanate building blocks, will be discussed in detail.