2-functional Addolink^® crosslinkers (chain extenders) react with isocyanates to polar urethane or urea domains which can agglomerate via intermolecular interactions and build stiff, crystalline “hard segments” as opposed to flexible “soft segments” built up by long-chained polyols.

This segmented structure is responsible for the excellent mechanical properties of PUR elastomers. LANXESS offers Addolink^® crosslinkers suitable for TDI- as well as MDI-based polyurethane prepolymers.
Products made with Addolink^® crosslinkers are used in a wide range of applications, such as: