INFLUENCE OF RHEOLOGICAL PROPERTIES OF ADHESIVE POLYMER ON STRAIN-ENERGY RELEASE RATE OF MODE-II AND ADHESIVE SHEAR-STRENGTH

It is well known that adhesive strength shows temperature and rate dep endencies reflecting viscoelastic properties of an adhesive used. Spec ifically, a mechanical relaxation mechanism around the glass transitio n temperature (T-g) has a strong effect on the adhesive strength, whic h involves deformation of the adhesive layer. In addition, it is very interesting to know how viscoelastic properties of the adhesive affect the value of strain energy release rate since deformation and failure of the adhesive occur at the measurement of strain energy release rat e for adhesive joints. In this study, adhesive tensile strength and st rain energy release rate (G(IIC)) in plain-shearing mode were measured under a constant experimental condition using adhesives consisting of two types of epoxy resins; the influence of viscoelastic properties o n these two values was investigated, and we discuss the relationship b etween the adhesive shear strength and G(IIC). (C) 1997 John Wiley & S ons, Inc.