Siloxane-decorated MXene nanosheet-reinforced EP composites with outstanding flame retardancy and liquid-oxygen compatibility for ultra-low-temperature applications

Abstract

Endowing epoxy resins (EPs) with satisfactory liquid-oxygen compatibility and ultra-low-temperature mechanical properties is an intractable challenge in the current aerospace industry. Appropriate flame retardants can provide systems with the above characteristics. This work modified the existing EP system through the surface modification of highly attractive MXene nanosheets with siloxane. The influence of additives on its comprehensive performance was further explored. The results indicated that when 2% KH550–MXene was added, EP nanocomposites showed optimum flame retardancy, liquid-oxygen compatibility, and ultra-low-temperature mechanical properties. Moreover, the EP nanocomposites achieved a flame-retardant grade of V-1, exhibiting no sensitivity phenomenon and demonstrating a 14.4% increase in ultra-low-temperature tensile strength (96.43 MPa at 77 K) compared with pure EP. The mechanisms underlying effective modification in this work are also dissected and summarised.