Green Approach for Toughening Thermosetting Reactive Resins

Thermosetting reactive resin systems such as epoxy, bismaleimide, and polyimide classes of material are brittle. The origin of brittleness is attributed to the high crosslinking density that exists in the fully cured forms of these materials. Traditionally, the toughness of these resins is enhanced by adding toughening agents such as rubber particles to the initial unreacted mixture of monomers and solvents. For the toughening of resin matrix fiber-reinforced composites, an interleafing approach is adopted. The interleafing approach is accomplished by inserting thermoplastic films (with inherent high toughness) alternately between the stacked prepreg plies, and then co-curing to form an integrated structural part.