Evaluation of Dynamic Mechanical Properties of Pressure Sensitive Adhesive in Paper Laminates for Postage Stamp Application:Method Development and Adhesive Characterization

摘要

Pressure-sensitive adhesives (PSA) are viscoelastic materials1 with flow properties playing a key role in the wetting and bond forming;their elasticity plays a key role in the storage of energy which can be used to resist the debonding process.The balance of these properties governs their time-temperature dependent responses and adhesion strength.The adhesion and other end-use properties of PSAs require a viscoelastic,non-Newtonian flow behavior which is based on the macromolecular nature of the adhesive.However,the pure PSA polymers are generally used as thin layers;therefore their flow is limited by the interactions with the solid components of the laminate (liner and face) materials.On the other hand the solid components of the laminate are commonly flexible,and/or elastic layers,allowing a relatively broad and non-uniform distribution of the applied stresses.Thus the properties of the bonded adhesive (adhesion strength) may differ from those of the pure adhesive.It remains merely difficult to introduce the properties of pure PSAs as valid evaluation information to the end-users and manufacturers.