Reasons for Adhesive Properties of Polyurethane and Diisocyanate-Based Adhesives

REASONS FOR ADHESIVE PROPERTIES OF POLYURETHANE AND DIISOCYANATE-BASED ADHESIVES 

The adhesion properties of isocyanate-based adhesives involves a combination of several chemical properties which will be examined in detail. These characteristics are summarized as follows  

Isocyanates react readily with a variety of other functional groups. Di- and polyisocyanates can undergo self polymerization to form three-dimensional resins in situ. 

Isocyanates are quite soluble in many organic substances, and due to their small molecular size readily permeate insoluble porous structures. 

The reaction of di- and polyisocyanates with hydroxyl-bearing polyesters and polyethers, co-reactants in many isocyanate adhesive applications, produces the strong, polar, hydrogen-bonded, flexible polyurethanes which, when wet, intimately contact and show strong attraction for a variety of surfaces. 

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