Investigation of Mechanical Properties of Pressure Sensitive Adhesives Part 1. Establishment of the Evaluating System of PSA by using Retardation Spectrum

Abstract

By using the laser-beam measuring equipment, the system to obtain the retardation spectrum of the pressure sensitive adhesive was completed. The exponential regression of the measurement data that contained the flow term was done. Then the smoothed measured data was numerically differentiated, and the retardation spectrum was obtained. In polymer/tackifier pressure sensitive adhesive system, the effect of the chemical structure and of the softening point of the tackifier resin were investigated. From the investigation, it becomes clear that the short time region of the retardation spectrum shape depends on the chemical structure of the tackifier, while the long time region of it depends on the softening point. This is the same as a past investigated result to base polymer. The mechanical properties of the pressure sensitive adhesives are clarified by studying the retardation spectrum. And this method will back up to design the pressure sensitive adhesive.