Balancing the electro-thermal-mechanical triolity of carbon fiber/silicone composite coatings: A soft-rigid interface strategy based on ZIF-8 nanoparticles

To meet the diversity of usage scenarios, it is often difficult to simultaneously achieve superior mechanical properties, antistatic properties, wave-transparent properties, and thermal stability in blended systems. In this study, on a “soft-rigid” interfacial concept, a multi-interface was constructed between low-temperature carbonized carbon fiber (CF) and silicone resin (SR) by grafting a “soft” polydopamine/polyethyleneimine layer and growing “rigid” ZIF-8 particles on the CF surface. The improved mechanical meshing and interfacial polarization of the “soft-rigid” interface enhanced the mechanical properties and thermal stability of CF/SR composites. Notably, the tensile strength and elongation at break of ZCF-3/SR were 36.54% and 40.43% higher, respectively, than those of UCF/SR with unmodified CFs. After being held at 350 °C for a duration of 3 h, the weight loss of ZCF-3/SR was 17.47% lower than the corresponding value of UCF/SR. Subsequently, the electrical analysis showed that the surface resistance of ZCF-3/SR was more stable than that of UCF/SR after heating and maintained the wave-transparent properties (ε<3.3, tan δ <0.2). The electromagnetic wave analysis of ZCF-3 alone at a higher filler content of 60 wt% showed that ZCF-3 achieved an effective absorption bandwidth of 5.9 GHz and a maximum reflection loss of −53.6 dB, which demonstrates the tunability of electromagnetic properties by varying fiber content and offers a broad design window of the composites. It has promising applications in lightweight and flexible aerospace electronics. Download: Download high-res image (265KB) Download: Download full-size image