LAUSR

Electrospun fibers have shown great potential for the interlaminar toughening. In this work, electrospun SBS fibers were incorporated into glass epoxy laminates. The mechanical properties of these SBS fibers are tuned using a triazolinedione cross-linker, where a higher amount of cross-linking gives rise to a lower elongation at break and a higher stiffness of the SBS fibers. Consequently, insights are provided into the relation between mechanical properties of electrospun fibers and enhancements in both Mode I and Mode II interlaminar fracture toughness. The SBS fiber’s mechanical properties affect the crack path in composites. Non and low cross-linked SBS fibers which have a very low stiffness promote crack growth with SBS fiber bridging under both Mode I and Mode II loading conditions. However, these SBS fibers need to elongate substantially in order to take up a significant amount energy (>300%). As this only occurs under Mode I loading conditions, the Mode I interlaminar fracture toughness can be improved. Nevertheless, the Mode II IFT is negatively affected. Higher cross-linked SBS fibers on the other hand, do take up more energy at much lower levels of elongation. As such, they can improve the Mode II interlaminar fracture toughness substantially.