A synergistic approach for thermal characteristic analysis of hibiscus rosa-sinensis/carbon nano-tubes/epoxy based hybrid composites using soft computing techniques

Abstract This study examines the thermal properties and combustion behavior of HRS/CNT hybrid polymer composites, focusing on how variations in CNT weight percentage, CNT diameter, sonication time, and composite thickness affect thermal conductivity, degradation temperature, and burning rate. The experimental results demonstrate that a CNT weight percentage of 3% significantly enhances thermal conductivity, achieving a maximum value of 0.985 W m −1 ·K, while also elevating the thermal degradation temperature to a peak of 457 °C. These enhancements are due to the effective formation of a CNT network that facilitates efficient heat transfer and increases thermal stability. Larger CNT diameters, specifically 3 nm, contribute to improved thermal and flame-retardant properties, resulting in a reduced burning rate of 5.18 mm min −1 compared to 11 mm/min for composites with 1% CNT and 1 nm diameter. Optimal sonication time at 60 min ensures uniform CNT dispersion within the polymer matrix, further enhancing thermal conductivity and reducing burning rates. Additionally, thicker composites (20 mm) exhibit lower burning rates and higher thermal degradation temperatures, serving as more effective thermal barriers. BPANN prediction is succesfully applied with a neglegible error of 0.15% compared with 0.68% error of RSM predictions. This research provides valuable insights into the design and optimization of polymer composites with tailored thermal and combustion properties, offering potential applications in fields requiring high thermal stability and flame resistance.