Hot-melt adhesives (HMA) are formulated systems with extensive use in packaged goods, particularly in the bonding of cardboard boxes.1 This type of system requires the application of the polymer/tackifier/wax adhesive in the molten state, followed by the adhesion action under an operation window in which the low-viscosity adhesive spreads over the substrate and rapidly solidifies to make the bond. In this scenario, the proper interaction between polymer and wax is required to dial in the specific physical properties and kinetics of solidification to successfully maintain the bond under a variety of conditions.
A recent study explored the basics of some of these interactions using blends of metallocene polyolefin elastomers and a selected range of waxes to probe their degree of interaction and their effect on viscoelastic properties. For this purpose, the study combined calorimetric and rheological results to better understand the kinetics of crystallization.