Facile and green synthesis of mechanically flexible and flame-retardant clay/graphene oxide nanoribbon interconnected networks for fire safety and prevention

Abstract

Water-based hybrid graphene oxide nanoribbon (GONR)/montmorillonite (MMT)/polyethylene glycol (PEG) networks were prepared by using a facile bio-inspired low-temperature evaporation induced assembling process. Multiple non-covalent and covalent interactions together with a high orientation level of MMT were constructed in the hybrid PEG/MMT/GONR networks. As a result, the hybrid networks exhibit synergistic reinforcing and toughening efficiencies when compared with the composites modified with the single-phase filler, e.g. 152% and 167% increase in tensile strength for the optimized ternary composites in comparison with those of the binary composites. Moreover, the nacre-like hybrid networks show excellent flame resistance and structural stability in a flame due to the formation of interconnected and compact char after combustion, which can be applied as protective coatings to combustible materials. The hybrid coatings not only improve the flame-retardant property (e.g. ~46% decrease in heat release rate at 30 wt%) of the combustible PU foam materials significantly, but also provide ideal fire alarm responses (e.g. rapid flame detection of ~2 s and effective fire early warning signals in pre-combustion). Owing to the green and versatile synthesis scheme, excellent mechanical performance and flame resistance, these hybrid PEG/MMT/GONR networks are promising widespread application.