Nylon 6,6 nanofibers were interleaved in the mid-plane of glass fiber/epoxy matrix composite laminates for Mode I and II fracture mechanic tests. The present study investigates the effect of the nanofibers on the laminates’ mechanical response. Results showed that Nylon 6,6 nanofibers improved specimen’s fracture mechanic behavior: the initial energy release rates GIC and GIIC increased 62% and 109%, respectively, when nanofibrous interlayer was used. Scanning electron microscope micrographs showed that nanofiber bridging mechanism enhances performances of the nanomodified specimens, still able to link the layers when the matrix is broken.
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