The Benefits of Caprolactone Technology in Reactive Hot Melt Adhesives
As market drivers accelerate the adoption of polyurethane reactive hot melt adhesives away from solvent-borne solutions, the use of polycaprolactone technology in reactive hot melt adhesive applications is examined.
Reactive hot melt adhesives provide advantages in a variety of end-application areas that include textiles, woodworking, construction, automotive, bookbinding, and electronics. A combination of the initial recrystallisation after application with the subsequent polyurethane polymerization gives this type of adhesive platform superior adhesion properties with enhanced chemical and heat resistance compared to traditional non-reactive hot melt adhesives.
Polycaprolactone is polymerized via a ring opening synthesis route, where caprolactone monomer is ring-opened via an initiator moiety. The initiator moiety is a hydroxyl functionalized molecule, which can be a diol, triol, or tetrol (Figure 1).