Blister Testing for Adhesion Strength Measurement of Polymer Films Subjected to Environmental Conditions

Abstract

A blister testing procedure combined with a numerical procedure can be used effectively for characterizing the adhesion strength. A challenge arises when it is implemented after subjecting samples to various environmental conditions. The concept of pseudoproperty is introduced to cope with the problem associated with property changes during environmental testing. The pseudoproperty set is determined directly from a deflection versus pressure curve obtained from a typical blister test. A classical energy balance approach is followed to evaluate the energy release rate from the critical pressure and pseudoproperty set. The proposed approach is carried out for an epoxy/copper interface after subjecting samples to full moisture saturation and a high temperature storage condition. In spite of significant change in property, the energy release rates are calculated accurately without extra tests for property measurements.