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In the last decade, polymer nanofibers have found promising application for improving through-thickness properties of structural composite laminates through interleaving. The main advantage of inserting nanofibers in conventional composites is making the matrix between the layers tougher. In this article, the benefits of using electrospun fibrous nano-interleaves in enhancing the quasi-static indentation response of aramid/epoxy laminated composites was investigated and the effect of variables of produced nano-interleaves including interleaf thickness (17.5, 35, and 70 µm) and stacking configuration (one-side, central, and two-side interleaving) on behavior of the nano-modified composites was investigated. The results indicate that force, displacement, absorbed energy, and stiffness of these composites are significantly affected by the presence of nano-interleaves. The optimum values were observed in the composites with 35 µm thickness of nano-interleave where three first parameters were higher than their reference values, but the stiffness value had opposite trend of other parameters. On the other hand, it can be seen that only asymmetrical (back-side indentation) stacking configuration lead to improving the composite properties. The visual inspection of the indentation damaged specimens reveals that thickness and stacking configuration of interleaves controls the size of damage.

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A cotton-based hemostatic dressing featuring antibacterial properties was developed with the potential of being used in traffic accidents to control hemorrhage. Cotton gauze was oxidized initially in an acidic medium and then coated by PVA nanofibers and/or PVA nanofibers loaded with Ciprofloxacin. Fabricated dressings were characterized by FTIR analysis and SEM images. The FTIR spectrum showed the existence of carboxyl groups on the oxidized cotton gauze's surface. The carboxyl groups content was estimated to be 17.3 ± 0.3 for the oxidized sample with a mixture of nitric acid and phosphoric acid for 24 h (OCF-Mixed acid24). Moreover, the effect of the exposure duration of cotton gauze in the acidic medium on the blood coagulation activity was assessed. It was observed that the OCF-Mixed acid24 sample exhibited an agreeable hemostatic activity (BCIs = 10). The antibacterial activity against E. coli and S. aureus bacteria was also captured for the coated cotton gauze by the PVA nanofibers loaded with Ciprofloxacin.