On the Interlaminar Properties of ENF Specimens of Glass/Epoxy Composites Incorporated Novel Hybrid Electrospun Interlayers

ABSTRACT This study investigates a novel approach that employs natural and organic materials to design electrospun interlayers, intending to enhance the mode II interlaminar fracture toughness (ILFT) of glass/epoxy composites. To this end, seven types of interlayers were manufactured using various weight percentages of two types of nanoparticles combined with water‐soluble PVA nanofibers. These nanoparticles are green composite nanoparticles, which are synthesized using lemon juice and consist of a SiO ₂ core and an Mg(OH) ₂ shell, and natural cork nanoparticles. Experimental investigations have demonstrated that incorporating these interlayers significantly enhances the load‐bearing capacity and improves delamination resistance, as evidenced by the R‐Curve analysis. Notably, PVA interlayers hybridized with 0.25 wt% cork and 0.75 wt% SiO ₂ /Mg(OH) ₂ nanoparticles resulted in remarkable increases of 201 and 122% in propagation ILFT compared to specimens without interlayers, respectively. Also, among these specimens, the PVA‐Cork‐0.25% interlayers demonstrated a 110% increase in initiation ILFT of glass/epoxy composites, along with a large‐scale fracture process zone (FPZ). Microscopy analysis of the specimen edges revealed a positive correlation between the jagged crack profile and the propagation ILFT value. Furthermore, SEM analysis of the fracture surfaces of specimens with interlayers identified fiber/nanofiber breakage as the primary mechanism observed in these specimens.