Thermosetting adhesive compositions formed from an epoxy resin containing nano-sized core-shell particles, one or more thermoplastic toughening agent containing an amine-terminated polyethersulfone, and at least one multi-functional epoxy resin, together with at least one amine curing agent to allow full cure of the adhesive composition up to 400° F. are provided herein. Such compositions are useful for forming adhesive films that can bond composite/metal/honeycomb structures for aerospace including bonding of aircraft leading or trailing edges, acoustic nacelle structures, horizontal and vertical tail, and various other structures, as well as for other high performance industrial applications.