The remediation of environmental boron contamination has received extensive research attention. The adsorbent ECH@NGM aerogel with high hydrophilic and mechanical properties was synthesized to remove boron. The ECH@NGM aerogel had a high adsorption capacity of 81.11 mg/g, which was 14.50% higher than that of commercial boron-selective resin Amberlite IRA743. The Freundlich model and pseudo-second-order model described the adsorption behavior well. In addition, the response surface methodology (RSM) could predict the experimental outcomes and optimize the reaction conditions, and X-ray photoelectron spectroscopy (XPS) and control tests were utilized to investigate probable adsorption mechanisms. These data showed that the B ← N coordination bond was the primary adsorption force. The adsorbent had good resistance to interference from coexisting salts, high reusability, good adsorption performance even after five reuse cycles, and a high desorption rate in a relatively short time. The adsorption performance in real brines could be maintained at 80%. Therefore, this work not only provided ECH@NGM aerogels for the removal of boron from brine but also elucidated the main adsorption processes between N-containing adsorbents and boron, facilitating the design of future adsorbents for boron removal.
Achieving simultaneous exceptional adhesion and recyclability remains a formidable challenge due to the inherent strength-toughness trade-off and stability-switchability conflict in adhesive systems. Inspired by the hierarchical architecture of cartilage, we report a bioinspired cross-linked network integrating B-N coordination bonds and dynamic boronic ester linkages for high-performance recyclable adhesives. The biomimetic design replicates the structural organization of cartilage's collagen-proteoglycan matrix, where dynamic B-N coordination bonds between network junctions facilitate energy dissipation through bond dissociation-induced network elongation. The network is constructed via 3-amino-1,2-propanediol-mediated epoxy ring-opening and subsequent cross-linking with 1,4-phenylenediboronic acid, forming a dynamic covalent polymer network, denoted as BEAD (boronic ester adhesive), with high cross-linking density. BEAD exhibits exceptional mechanical properties (46.42 ± 5.32 MPa tensile strength, 2.60 ± 0.31 MJ/m³ toughness) and robust adhesion (26.69 ± 0.74 MPa lap shear strength on steel). The synergy of B-N coordination (enhancing cohesion) and boronic ester exchange (enabling reprocessability) yields an optimal balance of strength and recyclability, retaining 80.7% adhesion performance after five reprocessing cycles. The study presents a biomimetic dynamic bonding strategy to overcome the strength-recyclability trade-off in adhesives, establishing a sustainable paradigm for structural materials.
Riting Huang,Furui He,Shujuan Yang,Keyang Mai,Shuntian Huang,Haifang Liu,Yuhong Feng,Gaobo Yu,Jiacheng Li
High quantum yield polysaccharide-based materials are significative for the dynamic anti-counterfeiting, while that are limited by weak fluorescence. However, natural polysaccharides with weak fluorescence are not suitable for anti-counterfeiting. Herein, alginate derivatives (SA-PBA) exhibiting aggregation-induced emission with high-quantum yields were synthesized by grafting phenylboronic acid (PBA) onto a sodium alginate (SA) chain. As the concentration increases, polymer assembly can be induced to form more compact soft colloidal aggregates, which enhances the fluorescence properties of alginate derivatives by introducing B ← N coordination bonds in the hydrophobic microregions. Interestingly, the clustered aggregates of SA-PBA can be dynamically controlled by pH, realizing the reversible adjustment of fluorescence. The corresponding mechanism is revealed by the combination of coarse-grained simulations and experiments. It is found that SA-PBA uses a hydrophobic driving force and hydrogen bond interaction to self-assemble in an aqueous solution and promote fluorescence emission. Moreover, the fluorescence quantum yield of SA-PBA can reach 14.4 % and can be reversibly altered by tuning soft colloidal microstructures. Therefore, a reversible information encryption system of SA-PBA is developed for anti-counterfeiting. This work shed some light on how to design novel anti-counterfeit materials based on natural polysaccharides and optimize the dynamic fluorescence conditions.