An applied interphase, between matrix resin and fibers in continuous f
iber composites, resulted in a significant improvement in composite im
pact strength and fracture toughness concurrently with a moderate impr
ovement or unchanged interlaminar shear strength. The temperature resi
stance of tailored interphases and composites was high. An optimum thi
ckness was observed. The merits of such interphases and a novel means
of application are discussed.