Flexible and lightweight carbon fiber/silicone resin composites with the “soft-rigid” structural interface for thermostable and antistatic applications

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2024-11, Vol.500, p.156862, Article 156862
• Main Authors: Liu, Siyu, Dong, Chunlei, Wu, Lianfeng, Li, Xiaoyu, Yu, Meijie, Zhou, Chuanjian
• Format: Article
• Language: English
• Subjects: Antistatic property; Carbon fiber; Silicone resin; Soft-rigid interface; Thermal stability
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.156862

•The PDA-PEI@octaphenyl-POSS acted as the modulus transition interface was successfully constructed between CF and SR.•The thermal and mechanical properties of the CF/SR composites improved due to the “soft-rigid” structural interface.•The interface improved the hardness management and maintained the antistatic properties after the bending and heating. To avoid a large difference in modulus between carbon fiber (CF) and silicone resin (SR) and unstable thermal properties, the “soft-rigid” structural interface is constructed by coating polydopamine-polyethyleneimine@octaphenyl-silsesquioxane (PDA-PEI@octaphenyl-POSS) on the fiber surface. The tensile strength of the CF-AE@3P/SR composite was 24.35 % higher than that of the unmodified CF/SR. The mechanism of mechanical enhancement revealed that the rigid layer with nanoparticles effectively deflected the crack and prolonged the path, and the hydrogen bonds and van der Waals forces helped disperse the stress concentration at the interface. The defects in the soft–rigid structural interface were reduced, and the decomposition of the fibers and composites was effectively inhibited, thereby increasing the heat transmission in the composites. After heating for 20 s on the heating plate at 200 °C, the surface temperature of the CF-AE@3P/SR composite was 155.4 °C, which is higher than that of the unmodified CF/SR (131.4 °C). Therefore, the thermal stability of the CF-AE@3P/SR composites was significantly improved compared to that of unmodified CF/SR after holding at 350 °C for 3 h. Surface resistance analysis showed that the soft–rigid modification maintained the antistatic properties of the composites at room and high temperatures. It was also found that the CF-AE@P/SR composites exhibited good flexibility, lightweight, and hardness for application in sealing and electronic components. This work provides ideas for forming a seamless transition and effective bonding between high-modulus carbon fibers and a low-modulus elastomer matrix, increasing the thermal stability and mechanical properties, and maintaining the flexibility, stiffness, lightweight, and antistatic properties of composites at high temperatures.