Investigating the material chemistry and performance evaluation of ZnO-based hybrid carbon fiber/waste silk reinforced polymer nanocomposites

The Present study aims to develop carbon fiber-based hybrid composite which utilizes waste silk as secondary reinforcement. Epoxy resin was used as potential binder which is modified from Zinc oxide nano particles added with varied range of 5,10 and 15 by wt% with the designated sample code of HF, HF/NP-5 %, HF/NP-10 %, and HF/NP-15 % respectively. Manual lay-up method was followed to develop composites, keeping the fiber to matrix ratio of 60:40. Developed composites were evaluated for 3-point bending, impact test followed by SEM analysis for understanding the failure mode. Thermal characteristics such as thermal stability and glass transition were evaluated to examine the thermal response of composites. Additionally, electrical resistivity of prepared samples was also evaluated to assess the multi-functional performance of developed hybrid polymer composites. Obtained results demonstrated that addition of ZnO nano particles improved impact strength from 54 ± 1.62–69 ± 2.41 kJ/m² and flexural strength from 286.53 ± 7.15–365.35 ± 9.05 MPa. Thermal studies revealed, improved degradation temperature from 183 °C to 264 °C with reduced wt. loss from 22.19 % to 5.47 % with notable increase in glass transition temperature (Tg) of 149.07 °C at 10 wt% ZnO with optimized hybrid configuration of HF/NP-10 % witness the excellence while comparing with other combinations due to uniformity in dispersion. Electrical resistivity decreased from 9.30 × 10⁻⁴ to 5.23 × 10⁻⁴ Ω·m, indicating improved conductivity. The results indicated that the HF/NP-10 % composite exhibited the optimal response across the tests conducted. • A Novel hybrid epoxy using carbon fiber, waste silk, & ZnO (5–15 wt%) was developed. • At 10 % ZnO, impact improved 54 ± 1.62→69 ± 2.41 kJ/m² and flexural strength to 365.35 MPa. • TGA reports thermal stability improved from 183→264 °C;Wt. loss lowered 22.19 %→5.47 %. • DSC results confirm, Glass transition temperature (Tg) raised from 102.79 →149.07 °C. • Resistivity dropped 9.30 × 10⁻⁴ →5.23 × 10⁻⁴ Ω·m as ZnO loading increased from 5 to 15 wt%.