Conventional and reactive
Hot melt adhesive systems with rapid bond strength
Conventional thermoplastic hot melt adhesives liquefy when heated. They crystallize and produce an adhesive bond during the subsequent cooling process and rapidly develop bond strength. Reactive polyurethane hot melt systems combine the properties of traditional hot melts with the advantages of chemically crosslinking adhesives.
Covestro offers a line of hydroxyl polyurethane raw materials for hot melts that are ideal for conventional and reactive systems.
Formulations for reactive polyurethane hot melts adhesives contain 2 percent to 5 percent isocyanate groups. These formulations demonstrate an additional chemical crosslinking in ambient humidity. This increases elevated temperature performance and water and solvent resistance of the finished product.
Typical raw materials of this category are the low-monomer MDI polyisocyanates, Desmodur® MDI monomers, Baycoll® polyesters and Desmophen® polyethers.
The final properties and process performance of conventional and reactive hot melt systems can be modified by adding suitable Desmodur® aliphatic or aromatic polyisocyanates.
Typical applications are sole bonding in the footwear industry, and adhesives for packaging, bookbinding, textiles, and electronics.
A total of
Product Overview, Products for reaction with polyisocyanates