Property-function co-upcycling of banana peel waste into robust, smart vegan leather enabled by marine biomass and liquid crystal elastomers

Abstract

The development of sustainable biomass alternatives has emerged as a promising strategy to address the pressing environmental concerns associated with petroleum-based plastics. Agricultural waste, such as fruit peels and stems, has been explored in this regard; however, its practical application remains limited owing to its insufficient mechanical strength and durability. Herein, we present a property-function co-upcycling strategy that transforms banana peel (BP) into an ultrastrong, functional vegan leather. The property upcycling is achieved by synergistically integrating BP powder (BPP) with a mutually interactive marine biomass matrix composed of sodium alginate and chitosan nanowhiskers, which form strong ionic interactions with each other and interfacial hydrogen bonding with BPP. This biomass reinforcement yields a tensile modulus and strength of 0.9 GPa and 33.1 MPa, respectively. The functional upcycling is realized through the surface lamination of a temperature-responsive liquid crystal elastomer (LCE), imparting programmable shape-morphing behavior within the temperature range of 30–80 °C. Moreover, water-assisted disintegration and reprocessing demonstrate the superior sustainability of the vegan leather. Consequently, this study highlights high value-added upcycling of BP waste and demonstrates a novel manufacturing strategy for next-generation vegan leathers that combine sustainability, mechanical robustness, and functionality.