Composites multifonctionnels électromagnétiques à base de nanomatériaux de carbone

Polymer composites with enhanced mechanical and functional properties are critical for lightweight, multifunctional structures in electromagnetic applications such as interference (EMI) protection and wave absorption (EMA). This work presents our recent advances in incorporating carbon nanomaterials into glass fiber-reinforced polymer composites to improve their electromagnetic (EM) shielding and absorption capabilities. Carbon nanotubes (CNTs) were in-situ grown on glass fibers (GF) via chemical vapor deposition, resulting in CNTs uniformly distributed along fibers hundreds of meters long. Systematic optimization of synthesis conditions was performed to enhance CNT growth and organization. Additionally, nickel-coated GF (GF@Ni) and GF with nickel and CNTs (GF@Ni-CNTs) were used for comparison. CNT grafting significantly improved interfacial properties between the polymer matrix and reinforcements, enhancing mechanical, electrical, and dielectric properties. EMI shielding effectiveness (SE) was studied as a function of CNT content, with GF@Ni-CNTs composites (9.2 wt% CNTs) achieving the best performance: SE > 35 dB from 1–18 GHz and >50 dB in the X-band. Incorporating a nickel layer further reduced CNT requirements for similar performance. These hierarchical composites, integrating in-situ grown CNTs, demonstrate great potential for EM wave absorption and EMI shielding applications.