Polyurethane Adhesives are known for toughness and flexibility even at low temperatures.
They have fairly good shear strength and excellent water and humidity resistance.
Polyurethane adhesives form strong bonds to rubber, plastics, metal, wood, paper, ceramic, and fabrics.
One-component polyurethane adhesives consist of isocyanate-containing prepolymers dissolved in a solvent carrier,
and reaction with moisture occurs as the solvent evaporates. Two-component polyurethanes consist of a polyol component (resin)
and an isocyanate component (hardener) that must be mixed in a defined ratio prior to application.
Two-component polyurethanes are used for large-surface adhesive bonds, like in in vehicle superstructures.
Polyurethane sealants are one-component, solvent-free sealants based on moisture cross-linking polyurethanes.
They cure to an elastic sealing compound by absorption of moisture from the air.