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.

With the escalating concerns over environmental pollution, effective management of industrial waste has emerged as a critical research focus in modern materials science. In this study, we developed cobalt-cobalt oxide doped lignin-based porous carbon materials (Co@CoO@MPC) by employing zeolitic imidazolate framework-67 (ZIF-67) decorated with industrial black powder—a byproduct rich in lignin and carbon. The synthesis involved potassium hydroxide (KOH)-assisted microwave activation, which enabled the creation of a porous structure, thereby markedly increasing the specific surface area and interfacial properties of the composites. During pyrolysis, ZIF-67 underwent transformation into cobalt (Co) and cobalt oxide (CoO) phases. The synergistic interaction between Co/CoO and the porous carbon significantly enhanced microwave absorption through both dielectric and magnetic loss mechanisms. The Co@CoO@MPC composites demonstrated exceptional microwave absorption properties across a broad frequency range, particularly at higher frequencies. Specifically, the sample after 2-min microwave irradiation exhibits a high EAB value of 5.7 GHz (1.6 mm thickness) and an RL_min value of −30 dB (2.0 mm thickness). This research not only offers an innovative approach to recovering resources from industrial black powder but also provides groundbreaking strategies for developing high-performance microwave-absorbing materials.

Oil pollution is a serious environmental and natural resource problem. Traditional adsorption materials for oil–water separation have limitations in terms of their preparation cost, reusability, and mechanical properties. Among the conventional adsorption materials, super-hydrophobic/super-lipophilic materials are easily contaminated by oil. In this study, polypropylene (PP) is used as a foam substrate to prepare an open-cell PP foam via hot pressing, supercritical CO₂ foaming, and electron beam (EB) irradiation. The impact of EB irradiation dose on the open-cell content of PP foam can lead to cell wall rupture, resulting in an open-cell structure that enhances oil-water separation performance. At an absorbed radiation dose of 200 kGy, the PP foams exhibit optimal oil–water separation performance, cyclic compression stability, heat insulation, and preparation cost. The open-cell content of PP foam is increased to 86.5%, the adsorption capacity for diesel oil is 42.8 g/g, and the adsorption efficiency remains at 99.6% after 100 cycles of oil desorption in a complex pH environment. Meanwhile, cracks and nano-voids simultaneously promote the capillary action of oil, and the oil transport rate is 0.0713 g/(g·s). This study provides a new concept for the preparation of open-cell polymer foams that can meet the demand for high oil-absorption capacity under complex acid-base pH conditions.