Polarization-dependent and mechanochromic dual-encryption composite textile enabled by robust and resilient cholesteric liquid crystal elastomer

Mechanochromic textile has attracted growing interest for applications such as limb motion monitoring, sensing and information encryption. Cholesteric liquid crystal elastomer (CLCE) is a promising candidate for mechanochromic textile due to its flexibility and ease of adhesion to textile substrates. However, synergistically improving the mechanochromic sensitivity, color uniformity, and reversible stability of CLCE remains a major challenge. Herein, we leveraged the density compatibility and intermolecular interaction between reduced graphene oxide (RGO), dichloromethane (DCM) and CLCE prepolymer to achieve uniform and stable RGO dispersion. Scrapping shear force was applied to induce alignment of both liquid crystal mesogens and RGO sheets. Subsequent solvent evaporation facilitated the helical self-assembly of cholesteric mesogens, producing RGO/CLCE composite films with high mechanochromic sensitivity, excellent color uniformity, and superior mechanical performance. These films were then integrated with elastic fabrics through thermal bonding, forming a composite textile with both physical and chemical adhesion. Notably, the resulting composite textile exhibited stable resilience and reversible mechanochromic behavior over 1000 stretching-recovery cycles. Furthermore, leveraging the circular polarization and mechanochromic properties, the composite textile enabled a dual-mode information encryption strategy. Thus, this work deepens the understanding of the interplay between microstructure, mechanical deformation, and optical properties in CLCEs, paving the way for advanced functional textile and multifunctional device.