MODE-I FRACTURE MODELING OF ELASTOMER-TOUGHENED POLYMERS

Analytical models are developed to correlate the model fracture toughn ess of elastomer-toughened polymers with microstructural damage modes occurring around the crack-tip. The total energy dissipation caused by three dominant damage modes, namely, plastic shear band formation, pl astic void growth, and plastic deformation of the entire matrix resin, is used as the basis to derive the analytical expression for the mode l fracture toughness of the toughened polymers. Numerical results are presented and compared with available experimental data for a typical toughened epoxy resin. Parametric results involving a number of materi al and microstructural variables indicate some very interesting trends , and provide some guidelines toward achieving optimum fracture toughn ess values for these types of material systems.