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Hydrogenated acrylonitrile–butadiene rubber (HNBR) is widely used in automotive and sealing applications due to its oil resistance and mechanical durability; however, its long-term performance is significantly influenced by the curing chemistry. Sulfur vulcanization offers superior elasticity but restricted thermal stability, while peroxide curing improves heat resistance at the expense of flexibility. In this study, we investigate hybrid sulfur–peroxide curing to integrate these benefits. The hybrid pathway encompasses competitive and sequential processes, such as partial radical quenching and accelerator oxidation, resulting in a dual crosslink network. Dynamic mechanical, thermal, and temperature scanning stress relaxation (TSSR) evaluations demonstrate that hybrid systems provide precise modulation of the operational temperature–frequency range, broaden the glass-transition relaxation, and control stress dissipation. The coexistence of sulfur and C–C crosslinks results in a heterogeneous structure characterized by diverse crosslink densities and bond energies, leading to numerous relaxation modes and an optimal blend of elasticity, strength, and thermal stability. Microscopy confirms the absence of phase separation, indicating that hybrid vulcanization is a viable approach for producing robust, high-performance HNBR elastomers.

Hydrogels are hydrophilic polymer materials that can swell but are insoluble in water. Hydrogels can be synthesized with synthetic or natural polymers, but natural polymers are preferred because they are similar to natural tissues, which can absorb a high water content, are biocompatible, and are biodegradable. The three-dimensional structure of the hydrogel affects its water insolubility and ability to maintain its shape. Cellulose hydrogels are preferred over other polymers because they are highly biocompatible, easily accessible, and affordable. Carboxymethyl cellulose sodium (CMCNa) is an example of a water-soluble cellulose derivative that can be synthesized using natural materials. A crosslinking agent is used to strengthen the properties of the hydrogel. Chemical crosslinking agent is used more often than physical crosslinking agent. In this review, article, different types of crosslinking agents are discussed based on synthetic and natural crosslinking agents. Hydrogels that utilize synthetic crosslinking agent have advantages, such as adjustable mechanical properties and easy control of the chemical composition. However, hydrogels that use natural crosslinking agent have better biocompatibility and less latent toxic effect.

Hyaluronic acid (HA) is an attractive extracellular matrix‐derived polymer. The related HA‐based hydrogels are emerging to be the hotspots in the cutting edge of biomaterials. The continuous sights concentrate on exploring modification methods and crosslinking strategies to promote the advancement of HA‐based hydrogels with enhanced physical/chemical properties and enriched biological performance. Here, the advances on modification methods and crosslinking strategies for fabricating HA‐based hydrogels with diverse capacities are summarized. Firstly, the modification reactions that occur on the active hydroxyl, carboxyl and N‐acetyl groups of HA molecule are discussed. Next, the emphasis is put on various crosslinking strategies including physical crosslinking, covalent crosslinking and dynamic covalent crosslinking. Finally, we provide a general summary and give a critical viewpoint on the remaining challenges and the future development of HA‐based hydrogels. It is hoped that this review can provide new proposals for the specific design of functional hydrogel biomaterials. The advances on modification methods and crosslinking strategies for fabricating hyaluronic acid‐based hydrogels with diverse capacities are summarized. The emphasis is put on various crosslinking strategies including physical crosslinking, covalent crosslinking and dynamic covalent crosslinking. A general summary and a critical viewpoint are provided on the remaining challenges and the future development of hyaluronic acid‐based hydrogels.

We report a facile method for encapsulation of carbonic anhydrase (CA) with magnetic nanogel (MNP-CA nanogel), in which amino and vinyl groups are first grafted onto the surface of magnetic Fe.sub.3O.sub.4 nanoparticles (MNP) using 3-aminopropyltriethoxysilane (APTES) and N-acryloylsuccinimide (NAS), followed by CA attachment with glutaraldehyde and in situ polymerization with acrylamide. The MNP-CA nanogel shows much improved thermostability at elevated temperatures, e.g. staying unchanged at 60 °C for 80 min, owing to multiple linkage with the hydrophilic polymer network coated at the MNP surface. Addition of the MNP-CA nanogel into a methyldiethanolamine (MDEA) solution at an ultralow mass ratio (1:10.sup.4) is able to enhance the CO.sub.2 absorption rate at 60 °C by 1.45 fold. The CA-enhanced mass transport of the absorbate has been demonstrated in a wetted-wall column, in which the MNP-CA nanogel increases the total mass transfer coefficient in the gas phase (K.sub.G) by 4.61 fold compared with that determined in the MDEA solution. The greatly increased absorption performance and much enhanced stability make MNP-CA nanogel appealing for industrial applications.

The physical characteristics of tumours are intricately linked to the tumour phenotype and difficulties during treatment. Many factors contribute to the increased stiffness of tumours; from increased matrix deposition, matrix remodelling by forces from cancer cells and stromal fibroblasts, matrix crosslinking, increased cellularity, and the build-up of both solid and interstitial pressure. Increased stiffness then feeds back to increase tumour invasiveness and reduce therapy efficacy. Increased understanding of this interplay is offering new therapeutic avenues. Tumours are often more stiff than normal tissue. In this Review, Mohammadi and Sahai discuss recent insights into how such altered tumour mechanics arise and how this affects tumorigenesis.

Semicoke, a coal pyrolysis product, is a cost‐effective and high‐yield precursor for hard carbon used as anode in sodium‐ion batteries (SIBs). However, as a thermoplastic precursor, semicoke inevitably graphitizes during high‐temperature carbonization, so it is not easy to form the hard carbon structure. Herein, we propose an oxidation‐crosslinking strategy to realize fusion‐to‐solid‐state pyrolysis of semicoke. The semicoke is first preoxidized using a modified alkali‐oxygen oxidation method to enrich its surface with carboxyl groups, which are localization points and the cross‐linking reactions occur with citric acid to build the semicoke precursor with homogeneous and abundant ‐C‐(O)–O‐ groups (up to 21 at% oxygen content). The ‐C‐(O)–O‐ groups effectively prevent the rearrangement of carbon microcrystals in semicoke during carbonization, resulting in the formation of an abundant pseudographite structure with larger carbon interlayer spacing and micropores. The optimized semicoke‐based hard carbon shows both a high initial Coulombic efficiency of 81% and a specific capacity of 307 mAh g−1, with low‐voltage plateau capacity increased to 2.5 times, compared to that of the unmodified semicoke carbon. By the combination of detailed discharge curves and in situ X‐ray diffraction analysis, the plateau capacity of semicoke‐based hard carbon is mainly derived from interlayer intercalation of Na+ ion. The proposed oxidation‐crosslinking strategy can contribute to the usage of low‐cost and high‐performance hard carbons in advanced SIBs. A novel oxidation‐crosslinking strategy was proposed for the first time to prepare semicoke‐based hard carbon anodes. The optimized optimal OHC‐2 electrode shows both a high initial Coulombic efficiency of 81% and a specific capacity of 307 mAh g−1, owing to this effective pretreatment method that can achieve the formation of abundant pseudographite structure with larger carbon interlayer spacing and micropore.

Nanogel-based nanoplatforms have become a tremendously promising system of drug delivery. Nanogels constructed by chemical crosslinking or physical self-assembly exhibit the ability to encapsulate hydrophilic or hydrophobic therapeutics, including but not limited to small-molecule compounds and proteins, DNA/RNA sequences, and even ultrasmall nanoparticles, within their 3D polymer network. The nanosized nature of the carriers endows them with a specific surface area and inner space, increasing the stability of loaded drugs and prolonging their circulation time. Reactions or the cleavage of chemical bonds in the structure of drug-loaded nanogels have been shown to trigger the controlled or sustained drug release. Through the design of specific chemical structures and different methods of production, nanogels can realize diverse responsiveness (temperature-sensitive, pH-sensitive and redox-sensitive), and enable the stimuli-responsive release of drugs in the microenvironments of various diseases. To improve therapeutic outcomes and increase the precision of therapy, nanogels can be modified by specific ligands to achieve active targeting and enhance the drug accumulation in disease sites. Moreover, the biomembrane-camouflaged nanogels exhibit additional intelligent targeted delivery features. Consequently, the targeted delivery of therapeutic agents, as well as the combinational therapy strategy, result in the improved efficacy of disease treatments, though the introduction of a multifunctional nanogel-based drug delivery system.

Understanding complex biological systems requires the system-wide characterization of both molecular and cellular features. Existing methods for spatial mapping of biomolecules in intact tissues suffer from information loss caused by degradation and tissue damage. We report a tissue transformation strategy named stabilization under harsh conditions via intramolecular epoxide linkages to prevent degradation (SHIELD), which uses a flexible polyepoxide to form controlled intra- and intermolecular cross-link with biomolecules. SHIELD preserves protein fluorescence and antigenicity, transcripts and tissue architecture under a wide range of harsh conditions. We applied SHIELD to interrogate system-level wiring, synaptic architecture, and molecular features of virally labeled neurons and their targets in mouse at single-cell resolution. We also demonstrated rapid three-dimensional phenotyping of core needle biopsies and human brain cells. SHIELD enables rapid, multiscale, integrated molecular phenotyping of both animal and clinical tissues.

The cytoskeleton and its components — actin, microtubules and intermediate filaments — have been studied for decades, and multiple roles of the individual cytoskeletal substructures are now well established. However, in recent years it has become apparent that the three cytoskeletal elements also engage in extensive crosstalk that is important for core biological processes. Actin–microtubule crosstalk is particularly important for the regulation of cell shape and polarity during cell migration and division and the establishment of neuronal and epithelial cell shape and function. This crosstalk engages different cytoskeletal regulators and encompasses various physical interactions, such as crosslinking, anchoring and mechanical support. Thus, the cytoskeleton should be considered not as a collection of individual parts but rather as a unified system in which subcomponents co-regulate each other to exert their functions in a precise and highly adaptable manner.

Thermoplastic elastomers (TPEs) combine the properties of plastics and rubbers. With new varieties continuously emerging, the TPE industry has experienced rapid development and gained increasing commercial significance. In this work, PP-based thermoplastic elastomers were prepared by blending five non-polar rubber components (BR, SBR, NR, IR, HVBR) with the polypropylene matrix. The damping properties of the resulting materials were systematically investigated, demonstrating the feasibility of developing novel thermoplastic damping materials using PP as the matrix.