Self-healing interface of carbon fiber reinforced composites based on reversible hydrogen-bonded interactions

The microscopic interfacial damages of carbon fiber reinforced composites (CFRCs) are difficult to repair and tend to initiate composites failure. Fortunately, the emergence of self-healing methods could effectively address this challenge. Herein, we report a self-healing interface based on the reversible hydrogen-bonded interactions in carbon fiber/polyvinyl alcohol (CF/PVA) composites system. By surface functionalization with dopamine (DA) containing active functional groups (e.g., –NH2 and –OH), the obtained polydopamine-functionalized CF (CF-PDA) possesses multiple reversible hydrogen bonds between PDA and PVA at the interface. The CF-PDA/PVA composites presented significantly higher interfacial bonding force (33%) than that of CF/PVA composites when hydrogen bonds were reconnected by thermal treatment. After five interfacial self-healing cycles, CF-PDA/PVA composites could recover a relatively high self-healing efficiency (∼73.6%). Moreover, the self-healing mechanism is further discussed by molecular dynamics simulation. The strategy of reversible hydrogen-bonded interactions is promising for developing high-performance self-healing carbon fiber reinforced composite materials.