## 4 Discussion  
The findings of this study provide compelling evidence that the dual modification of GFRP laminates through the incorporation of polyethylene (PE) powder and electrospun polyacrylamide(PAN) nanofiber mats can significantly enhance both impact resistance and thermal self-healing capabilities. Compared to the poor performance of virgin composites, the modified systems exhibited superior damage tolerance and partial mechanical recovery. PE-modified specimens demonstrated viscoelastic deformation and thermoplastic flow, which helped limit strength loss and enabled a significant increase in peak load following thermal treatment. Meanwhile, PAN-interleaved laminates effectively suppressed initial damage propagation, although they showed limited recovery after heating. A detailed comparison of load-bearing capacity and energy absorption values for each specimen group is presented in Table 2 to support these findings. Upon examining the table, it can be seen that virgin composites exhibited the lowest post-impact performance, with up to a 30% reduction in load capacity after repeated or thermally treated impacts (V1U, V2T), underscoring the brittle nature of neat epoxy and its limited ability to recover after treatment. Although a slight increase in energy absorption was observed after impact, this was likely due to matrix cracking increasing, rather than meaningful recovery. Nanofiber-interleaved specimens demonstrated improved damage tolerance, the untreated specimens retaining up to 10% more load capacity, and the electrospun PAN mat effectively delayed delamination and distributed stress, resulting in enhanced energy absorption (up to +20%) compared to the virgin specimens. However, thermal conditioning of these samples (N2T) resulted in a -15% reduction in peak load. Although the microstructural integrity was largely preserved, the absence of a healing agent combined with thermal expansion mismatches likely contributed to the observed decline in performance. PE-modified specimens showed a markedly different response. P1U exhibited a 20% drop in load capacity. Post-healing improvements were more pronounced in P2T, with energy absorption increasing by 8%, and load capacity recovering to its pre-impact level. These findings affirm that molten PE could be successful in working as a healing agent, albeit with limited influence on restoring maximum load-bearing strength. \begin{table}
\begin{tabular}{c c c c c} \hline
**Specimen** & **Load Capability** & **Change in Load (\%)** & **Energy Absorption** & **Change in Energy Absorption (\%)** \\
**Type** & **[N]** & **Change in Load (\%)** & **[J]** & **Absorption (\%)** \\ \hline V1 & \(1950\pm 150\) & Reference & \(8.1\pm 0.38\) & Reference \\ V1U & \(1450\pm 190\) & \(-25\%\) & \(9\pm 0.36\) & \(10\%\) \\ V2 & \(1900\pm 150\) & \(-2\%\) & \(9\pm 0.38\) & \(10\%\) \\ V2T & \(1350\pm 120\) & \(-30\%\) & \(9\pm 0.42\) & \(10\%\) \\ N1 & \(2150\pm 140\) & Reference & \(9\pm 0.32\) & Reference \\ N1U & \(2150\pm 150\) & \(0\%\) & \(9.8\pm 0.3\) & \(9\%\) \\ N2 & \(2120\pm 140\) & \(1\%\) & \(9\pm 0.29\) & \(0\%\) \\ N2T & \(1800\pm 150\) & \(-15\%\) & \(9.8\pm 0.31\) & \(9\%\) \\ P1 & \(2000\pm 135\) & Reference & \(10.3\pm 0.44\) & Reference \\ P1U & \(1600\pm 200\) & \(-20\%\) & \(10.6\pm 0.39\) & \(3\%\) \\ P2 & \(2050\pm 135\) & \(1\%\) & \(10.2\pm 0.42\) & \(1\%\) \\ P2T & \(2000\pm 150\) & \(0\%\) & \(11.1\pm 0.41\) & \(8\%\) \\ H1 & \(2350\pm 130\) & Reference & \(7.3\pm 0.3\) & Reference \\ H1U & \(2250\pm 140\) & \(-4\%\) & \(7.1\pm 0.31\) & \(-3\%\) \\ H2 & \(2320\pm 130\) & \(1\%\) & \(7.4\pm 0.34\) & \(1\%\) \\ H2T & \(2750\pm 150\) & \(17\%\) & \(8.5\pm 0.33\) & \(17\%\) \\ \hline \end{tabular}
\end{table} 
Table 2: Quantitative evaluation of load capacity and energy absorption capabilities of the specimens under low-velocity impact. The hybrid laminates, which integrated both polyethylene powder and electrospun PAN nanofiber mats, exhibited the most promising performance among all configurations.