## 2 Materials and Methods  
Electrospinning was employed for the fabrication of the nanofiber mats. The polyacrylamide-trile (PAN) solution was prepared by dissolving PAN powder in dimethylformamide (DMF), with both the polymer and the solvent procured from Sigma-Aldrich. The PAN polymer is characterized by the chemical formula (C\({}_{3}\)H\({}_{3}\)N)\({}_{n}\), a molecular weight of 1.5 \(\times\) 10\({}^{5}\) g/mol, a glass transition temperature of 85 \({}^{\circ}\)C, a melting point of 317 \({}^{\circ}\)C, and a density of 1.184 g/mL at 25 \({}^{\circ}\)C.  
Then, PAN powder was dissolved in DMF at a concentration of 12% \(w/w\)[39] in a screw-capped glass bottle and left to rest for 48 h under ambient conditions to ensure complete solvation. The resulting solution was subsequently treated in an ultrasonic bath for 8 h at room temperature to enhance homogeneity and dispersion. Finally, the homogeneous solution was loaded into a 10 mL syringe and mounted onto a syringe pump system for electrospinning. Parameters such as solution viscosity, electric field strength, needle-to-collector distance, and ambient humidity play a critical role in determining the diameter and morphology of the resulting fibers. Accordingly, the electrospinning process was conducted under the following conditions: an applied voltage of 20 kV, a tip-to-collector distance of 150 mm, a solution feed rate of 1 mL/h, and a rotating drum collector with a circumference of 220 mm and a length of 130 mm, operated at 70 rpm. The ambient temperature was maintained at 25 \({}^{\circ}\)C with a relative humidity of approximately 50%. The process was continued until the entire polymer solution had been consumed. Following electrospinning, the nanofiber mats were dried at room temperature under continuous dehumidification for 72 h to ensure the complete evaporation of residual solvents. Subsequently, they were stored in sealed plastic containers for later use. The electrospun mats exhibited an average thickness of 2.98 \(\pm\) 0.3 \(\upmu\)m, and the surface density was calculated as 50.8 \(\pm\) 0.22 g/m\({}^{2}\) by dividing the total weight of the nanofiber mat (Figure 1a) by its surface area. The morphological characteristics and surface quality of the fibers were analyzed using scanning electron microscopy (SEM) (Figure 1b). SEM imaging was performed using a Thermo Fisher Scientific Apreo S LoVac device. Specimens were placed in a clean vacuum chamber to prevent dust interference and minimize particulate contamination. As no surface coating or conductive preparation was deemed necessary, the samples were imaged in their original state. Multiple regions of the mats were examined at various magnifications to ensure image clarity and consistency, and the highest-quality micrographs were selected for analysis. The SEM results confirmed that the electrospun nanofibers were suitable for use in composite fabrication. Fiber diameters were measured using ImageJ software v1.51 equipped with the Diameterj plugin v1.018 [48], revealing an average diameter of 419.1 \(\pm\) 66.01 nm (Figure 1c). Although some variability in fiber diameter and continuity were observed, the overall distribution remained within acceptable limits, and given that the standard deviation was less than 0.5, a Gaussian distribution [49] was also calculated for statistical analysis, which confirms a valid distribution. The polyethylene (PE) used in this study was supplied in powder form by Arya Sasol Polymer Company, with an average particle size of 200 \(\upmu\)m. The material exhibits a high density of 0.95 g/cm\({}^{3}\) (at 23 \({}^{\circ}\)C), a melt flow index (MFI) of 10 dg/min (190 \({}^{\circ}\)C/12.6 kg), a Young's modulus of 1050 MPa, a tensile strength of 55 MPa, a tensile stress at yield of 26 MPa, and a melting point of 132 \({}^{\circ}\)C.  
A commercial epoxy resin system (MGS L160/H160) was employed as the matrix and mixed with its corresponding curing agent at a weight ratio of 100:25, in accordance with the manufacturer's instructions (Figure 2a).