MODELING THE PROPERTIES OF RUBBER-MODIFIED EPOXY POLYMERS

A finite-element model for rubber particles in a polymeric matrix has recently been proposed which is based upon a collection of spheres, ea ch consisting of a sphere of rubber surrounded by an annulus of matrix . We have used this model to investigate in detail the stress distribu tions in and around a rubber particle, or a void, in a matrix of epoxy polymer. We have deduced the bulk modulus of the rubber-toughened epo xy and considered the implications of the stress distributions on the observed toughening micromechanisms. Of particular concern has been th e effects of the volume fraction and the properties of the rubber phas e.