Optically clear pressure-sensitive adhesives for foldable optical devices require a balanced combination of adhesion, optical transparency, creep resistance, and bending durability. In this work, a semi-interpenetrating network organogel OPSA, was designed and prepared to improve the dynamic bonding stability under repeated deformation. A ureido-containing polar acrylate monomer was first synthesized from 2-isocyanatoethyl methacrylate and butylamine, and then copolymerized with 2-ethylhexyl acrylate and acrylic acid to obtain linear polyacrylate (PA-1). Meanwhile, a cross-linked network (PA-2) was constructed by photopolymerization of a polypropylene glycol-based polyurethane acrylate flexible cross-linker (PUA), 2-ethylhexyl acrylate, and hydroxyethyl acrylate. The final OPSA was formed by combining PA-1, PA-2, and 1,5-pentanediol as a polar small molecule. In this system, the semi-interpenetrating network formed by PA-1 and PA-2 improves elastic recovery and creep resistance, while 1,5-pentanediol introduces abundant reversible hydrogen-bonding interactions, thereby enhancing stress dissipation during bending. The optimized OPSA containing 10 wt.% 1,5-pentanediol exhibits the best overall performance, including a 180 degrees peel strength of 12.5 N/25 mm, recovery efficiency above 93%, transmittance of 92.3%, haze of only 0.22%, and excellent folding durability over 300 000 cycles. These results demonstrate that combining a flexible semi-interpenetrating network with reversible hydrogen-bonding interactions is an effective strategy for developing high-performance OPSAs for dynamic optical devices.

ABSTRACT Currently, commercial photoinitiators and their corresponding photoinitiation systems are predominantly suitable for ultraviolet (UV) curing, which limits their broader applicability. Consequently, developing novel photoinitiators compatible with visible light LEDs has emerged as a critical research focus. This study designed and synthesized three hydrogen‐abstraction radical photoinitiators (PI1–3) operable under visible light by incorporating aldehyde‐functionalized phenothiazine units into an indole acetate framework. Spectroscopic characterization revealed that PI1–3 exhibited maximum absorption wavelengths at 501, 506, and 489 nm, respectively, demonstrating a significant red‐shift compared to the commercial photoinitiator benzophenone (BP, λ max = 257 nm), with absorption extending beyond 600 nm. The results of photopolymerization showed that the final double bond conversion of PI‐3 reached 99% under LED@500 nm light source irradiation. On the other hand, the migration stability evaluated via an immersion–extraction method indicated that after 24 h, the migration rates of PI1–3 were 1.7%, 1.4%, and 0.7%, substantially lower than that of BP (22.5%). These results underscore the advantages of PI1–3, including long‐wavelength absorption, low migration propensity, and straightforward synthesis, positioning them as promising candidates for visible light‐induced polymerization applications.

Abstract Developing soft materials that integrate high mechanical performance, self-healing, adhesion, and stimulus-responsive functions remains challenging due to the trade-off between dynamic reversibility and mechanical resilience. Here, we report a P(AA-MA-OA-FHMA) hydrogel fabricated via one-pot free-radical copolymerization, in which hydrophobic association and multivalent hydrogen bonding are synergistically integrated as dual dynamic cross-linking mechanisms. The salicylaldehyde-derived monomer (FHMA) serves as a triple-functional building block, providing hydrophobic domains, hydrogen bonding sites, and metal-chelating coordination sites. The hydrogel exhibits an ultrahigh fracture strain exceeding 4000%, a tensile strength of 278 kPa, self-healing efficiency of ∼75% at room temperature, and an adhesion strength of 40 kPa on porcine skin. The FHMA moieties enable multicolor fluorescence (blue with Zn2+, green with Al3+, and orange with hydrazine hydrate), while Al3+ coordination imparts selective antibacterial activity against Escherichia coli with nearly 100% killing efficiency. The ionic conductivity further enables strain-responsive sensing for both joint movements and subtle physiological activities. This work provides a simple platform for constructing multifunctional hydrogels with potential applications in wearable electronics, biointerfaces, and wound dressing.

Photodynamic therapy (PDT) is a promising non-invasive strategy for breast cancer, yet its clinical translation is hindered by fluorescence quenching, insufficient reactive oxygen species (ROS) generation and poor tumor targeting. Herein, a novel lipid droplet-targeted aggregation-induced emission (AIE) photosensitizer CTC was designed and synthesized. CTC has a large Stokes shift of 150 nm to avoid self-absorption and exhibits typical AIE properties in aqueous environments. Under white light irradiation, it efficiently generates three cytotoxic ROS (1O2, ·OH, O2•-), with a high colocalization coefficient of 0.95 with lipid droplets in 4 T1 cells. CTC shows excellent biocompatibility in the dark and potent phototoxicity under illumination. In vivo, CTC combined with light significantly inhibits 4 T1 tumor growth without systemic toxicity. Density functional theory calculations elucidate its multi-type ROS generation mechanism, providing a novel candidate and new insight for safe and efficient breast cancer PDT.

Hydrogels possess high water content, excellent biocompatibility, and good processability, and hold great application potential in biomedicine, materials science, and other fields. However, they suffer from poor mechanical properties and insufficient functionality. Additionally, fluorescent hydrogels exhibit inadequate stability, which severely limits their practical applications. To meet these requirements, we report herein a high-strength and tough fluorescent hydrogel with excellent mechanical properties, which also exhibits outstanding antibacterial performance and fluorescent writing capability. A hydrazone-containing hydrophobic monomer (BHPAA) was incorporated into the hydrogel system via a solvent exchange method to design and fabricate P(AM-BHPAA) hydrogels based on hydrophobic interactions. Meanwhile, fluorescent Zn2+-P(AM-BHPAA) hydrogels were prepared by exploiting the coordination between hydrazone structures and metal ions. These hydrogels exhibit enhanced mechanical properties and are endowed with fatigue resistance, where the mechanical performance is regulated by the content of BHPAA and the concentration of Zn2+. The maximum tensile fracture strain and stress are 405% and 1.07 MPa, respectively, with a maximum toughness of 3.38 MJ/m3. After complexation with Zn2+, the hydrogel emits blue-green fluorescence, and the maximum fluorescence intensity increases by 1402% compared with that before complexation. Taking advantage of the approximate linear relationship between fluorescence intensity and Zn2+ concentration, this hydrogel can be used for the detection of Zn2+ concentration.

To address the critical limitations of conventional photoinitiators, including complex synthesis, poor LED wavelength matching, and high molecular mobility, this study rationally designed and synthesized ten vinyl ketone derivatives functionalized with diverse electron-donating substituents. Five of these structures, HMPO-4, HMPO-5, HMPO-6, HMPO-7, and HMPO-8 were found to possess excellent photo-initiating activity, with the maximum absorption wavelengths red-shifted to the visible region, with a maximum molar extinction coefficient of more than 24,000 M- 1cm- 1. The multi-component HMPO initiation system effectively initiated PEGDA polymerization under 405 nm and 480 nm LED irradiation, with HMPO-6 exhibiting optimal performance, achieving C--C double bond conversions of 96% and 91%, respectively. Steady-state photodegradation and ESR spectroscopy analyses revealed favorable photochemical properties, along with excellent solubility and biocompatibility. Notably, HMPO-6 demonstrated superior migration stability, exhibiting a minimal migration rate of 0.9%. Furthermore, this novel photoinitiator enabled efficient 3D printing under low-intensity (5 mW/ cm2) 405 nm LED irradiation.

In response to the known limitations of smart optical hydrogels, which suffer from poor mechanical properties and lack of antibacterial performance, we report a smart optical metallic hydrogel (Zn2+-P(AM-EMA-BMHPD)) with excellent elongation, antibacterial capability, and controllable fluorescence intensity. The solvent exchange method was successfully used to incorporate the diacylhydrazone-based hydrophobic cross-linker (BMHPD) into the hydrogel system, resulting in P(AM-EMA-BMHPD) hydrogels with dual chemical covalent and hydrophobic physical cross-linking. BMHPD serves as both a monomer and a cross-linking agent, reducing the use of functional monomers and further enhancing mechanical properties. The maximum tensile strain and stress are 515% and 1.76 MPa, respectively, with a maximum toughness of 5.11 MJ/m3. After complexation with Zn2+, the hydrogel exhibits blue fluorescence, with the fluorescence intensity increasing by 535% compared to before complexation. The incorporation of the acylhydrazone structure imparts excellent antibacterial properties to P(AM-EMA-BMHPD) hydrogels, with optimal inhibition rates of 62% and 98% against E. coli and S. aureus, respectively. Furthermore, based on the controllable regulation of Zn2+ by P(AM-EMA-BMHPD) hydrogels, an erasable fluorescence writing process was designed, which exhibits the ability to be repeated multiple times.

Against the backdrop of green and sustainable development in the polyurethane industry, nonisocyanate polyurethane (NIPU) has increasingly attracted attention as a promising alternative. Among various synthetic strategies, the synthetic route using cyclic carbonates and polyamines to prepare NIPU stands out for its exceptional application potential. In this study, soybean oil-based cyclic carbonate (TSO) was synthesized from soybean oil and thioglycerol under atmospheric pressure. Subsequently, a series of nonisocyanate polyurethanes (S-NIPU) with high biobased content were prepared through copolymerization of TSO with biobased diamines. Different from conventional linear NIPU, TSO provides multifunctional cyclic carbonate groups, enabling the formation of a three-dimensional cross-linked network upon amination. This robust network structure significantly enhances both the thermal stability and mechanical properties of S-NIPU. The results demonstrate that S-NIPU exhibits excellent and tunable tensile properties, with a tensile strength of 2.4 MPa and an elongation at break of 139%. Simultaneously, owing to the dynamic interactions between carbamate and hydroxyl groups, as well as multiple hydrogen-bond rearrangements, S-NIPU displays outstanding self-healing capability. Following thermal treatment, the self-healing efficiency reaches up to 94%. Furthermore, S-NIPU can be chemically recovered, reprocessed, and recycled in ethanol solutions. After three recycling cycles, it retains 91% of its original mechanical performance. This work begins with molecular structure design and employs a green, facile strategy to synthesize biobased S-NIPU materials, which exhibit significant potential for applications in coatings and adhesives.

Thiophenol (PhSH) is a highly toxic aromatic thiol endangering ecosystems, food safety, and human health. Traditional detection methods are limited by instrument dependence and inability for real-time imaging. This study developed a red-emitting fluorescent probe, TTCP-DN, based on the PET mechanism. The probe employs 5-(4-diphenylamino)benzothiophene as the fluorophore and 2,4-dinitrophenoxy as the PhSH-specific recognition moiety, achieving mitochondrial targeting via a pyridine salt. Without PhSH, fluorescence is quenched; upon PhSH-induced reaction, fluorescence restores at 623 nm. The probe has low detection limit (37.8 nM), large Stokes shift (153 nm), good biocompatibility, and high selectivity. It was applied for mitochondrial imaging in 4 T1 cells, qualitative detection and semi-quantitative concentration trend analysis of PhSH in zebrafish, plant tissues, environmental, food and biological samples (recoveries 95-105%), and fabricated into portable paper-based test strips. This work provides a versatile PhSH detection tool and a paradigm for targeted probes of toxic aromatic pollutants.

Zinc-ion batteries (ZIBs) are regarded as promising candidates for flexible wearable electronics due to their high safety, environmental friendliness, and low cost. However, the uncontrollable dendrite growth and side reactions at the zinc anode hinder their practical application. Here, we report a multinetwork antifreeze eutectogel (SB eutectogel) electrolyte that demonstrates superior self-healing efficiency (70%) with Schiff base. The synergistic effects of the dynamic imine bonds and metal-coordination interactions endow the SB eutectogel with antifreezing capability (Tg = -95.1 °C), robust environmental adaptability, a strong binding energy of -35.68 eV, high conductivity (1.71 mS·cm-1), and a wide electrochemical stability window, which collectively suppress zinc dendrite growth and parasitic reactions throughout cycling. The Zn//Zn symmetric cell with this electrolyte demonstrates an extended cycling life of 1800 h (0.2 mA·cm-2/ 0.2 mAh·cm-2), and the Zn//PANI full cell exhibits 80.15% retention of its original specific capacity after 2850 cycles, with an average Coulombic efficiency of 99.88%. Furthermore, the Zn//Zn cell exhibits prolonged cycling stability, with a duration of 800 h at -20 °C (0.1 mA·cm-2/0.1 mAh·cm-2). Additionally, flexible batteries based on SB eutectogel electrolytes can power light bulb at low temperatures. This Schiff-based eutectogel electrolyte with excellent self-healing efficiency, freezing resistance, and high electrochemical stability is expected to pave the way for the development of high-performance flexible energy storage and wearable devices.

Two-component waterborne polyurethane is composed of water-based polymer polyols and water-dispersible polyisocyanates. Among them, hydroxyl polyacrylate aqueous dispersion (PAD) has attracted extensive research interest owing to its small particle size and exceptional film-forming performance. However, conventional PAD suffers from critical limitations, including low solid content and insufficient chemical resistance of cured film, which severely restrict its industrial applications. To address these drawbacks, a sulfonic acid-containing vinyl hydrophilic monomer was synthesized to fabricate high-solid and low-viscosity PAD, followed by organosilicon modification. The effects of organosilicon type and dosage on the properties of PAD and its cured film were systematically investigated. Results reveal that the dosage of vinyl-based sulfonate enhances the solid content of PAD and improves coating transparency. Organosilicon incorporation effectively boosts the chemical resistance of the coating film but compromises the storage stability of PAD. Notably, PAD modified with vinyl triisopropoxysilane (KH1706) exhibits optimal overall performance, with a solid content of 45%, a low viscosity of 357 mPa s, along with excellent chemical resistance and thermal stability.

Trimellitic anhydride-based cyclic carbonate (TAC) was synthesized via the ring-opening reaction of glycerol carbonate (GC) and trimellitic anhydride under atmospheric pressure. The resulting TAC was then reacted with epoxidized soybean oil (ESO), followed by neutralization and dispersion to form aqueous soybean oil-based cyclic carbonate (ECC) dispersions. This study examines the influence of the carboxyl-to-epoxy group ratio on the stability of the ECC dispersion. A series of non-isocyanate polyurethanes (NIPUs) were subsequently prepared by curing ECC with diamines, and their mechanical properties and thermal stability were evaluated. Results indicate that NIPU-2 samples, cured with 1,6-hexanediamine (HAD), exhibited the highest elongation at break, reaching 347.14

Mitochondrial autophagy is closely related to various diseases such as neurodegenerative diseases and cancer, and changes in mitochondrial polarity are key markers of these diseases. Traditional fluorescent probes rely on membrane potential and often lose signal during key stages of autophagy. This work develops a mitochondria-immobilized fluorescent probe, Mito-NT, which uses naphthylimide as the fluorescent moiety, triphenylamine as the electron donor, pyridine salt as the electron acceptor, and a mitochondrial-targeting group. The probe achieves polarity-dependent fluorescence response through the activation of an intramolecular charge transfer (ICT) mechanism. The active chlorine unit in its structure ensures that the probe remains stable in the mitochondria and is not affected by changes in the membrane potential. Mito-NT exhibits high polarity sensitivity, pH stability, strong interference resistance, and low cytotoxicity, enabling dynamic monitoring of the mitochondrial autophagy process, tracking the fusion of mitochondria and lysosomes, and distinguishing mouse hunger-induced cardiac mitochondrial autophagy (manifested as enhanced fluorescence). This probe provides a powerful tool for mitochondrial autophagy research and related disease diagnosis.

Flexible strain sensors have garnered significant interest for applications in wearable devices, health monitoring, and electronic skin. However, their functionality is typically confined to electrical signal output, lacking an intuitive visual feedback mechanism, which severely limits their application in scenarios requiring rapid visual interaction. Although attempts have been made to integrate color-changing mechanisms, the mechanical and electrical properties of existing systems are often inadequate. This paper presents a simple yet effective strategy for preparing a multifunctional hydrogel with outstanding mechanical properties, conductivity, and photochromic characteristics by copolymerizing acrylamide (AAm), (3-acrylamidopropyl) trimethylammonium chloride (APTAC), octadecyl acrylate (C18), and rhodamine B-3-allylsalicylaldehyde hydrazone. Benefiting from the synergistic effects of dynamic ionic interactions, hydrophobic associations, hydrogen bonding, and coordination, the resulting hydrogel exhibits ultrahigh extensibility (fracture strain 2550%), high sensitivity (a gauge factor of up to 29.17), and rapid photochromic performance. Leveraging this highly integrated functionality, the hydrogel successfully enables a novel flexible device capable of simultaneously achieving precise electrical monitoring of human motion, visual information display, and encryption. This work not only provides a high-performance material but also demonstrates an effective strategy for achieving multifunctional integration through rational molecular design, thereby advancing the development of next-generation intelligent, flexible electronics.

Four novel benzophenone photoinitiators were synthesized by one-step reaction, including (4-(dimethylamino) phenyl)(10-ethyl-10H-phenothiazin-3-yl)methanone (PEPM), (4-(dimethylamino)phenyl)(10-phenyl-10H-phe- nothiazin-3-yl)methanone (PPPM), (10-allyl-10H-phenothiazin-3-yl)(4-(dimethylamino)phenyl)methanone (PAPM) and (4-(dimethylamino)phenyl)(10-(hex-5-en-1-yl)-10H-phenothiazin-3-yl)methanone (PHPM). Compared with benzophenone (BP), the absorption spectra of PIs are red-shifted to the visible light range, with a high molar absorption coefficient and wide absorption range from 365 nm to 475 nm. Surprisingly, under the irradiation of low intensity LED@405 nm (5 mW/cm2) and LED@440 nm (5 mW/cm2), PIs can initiate free radical polymerization and undergo rapid polymerization of PEGDA 400. Among them, the double bond conversion rate (DC) of PPPM reaches a stable value (98 %) within 20 s, which is much higher than that of BP (65 %). In addition, the curing depth of PPPM reaches 8.1 cm under the irradiation of LED@440 nm. Besides, PPPM can still perform multi-color 3D printing with 3 s/slice after adding different color (black, red, blue and yellow) dyes. At the same time, we explored the photopolymerization mechanism of the photoinitiator through photo- degradation and ESR tests.

To solve the problem of poor film flatness of matte waterborne polyurethane (WPU) prepared with additional matting agent and the shortcomings of poor water and heat resistance of vegetable oil-based WPU, the bio-based emulsifier monotrihydroxyethyl isocyanurate succinate (SATH) was prepared by using succinic anhydride and trihydroxyethyl isocyanurate and used together with sodium salt of 2-(2-aminoethyl)aminoethanesulfonate (SAAS) to prepare castor oil-based self-matting WPU. Compared with the WPU prepared using dimethylolpropionic acid, the WPU prepared using SATH showed better water and heat resistance, with a reduction in water absorption from 34.31

A series of Type II photoinitiators (PIs) bis(5-(4-(diethylamino)phenyl)thiophen-2-yl)methanone (EATM), bis(5-(9-ethyl-9H-carbazol-3-yl)thiophen-2-yl)methanone (ECTM) and bis(5-(4-(diphenylamino)phenyl)thiophen-2-yl)methanone (PATM) based on di-2-thienyl ketone were synthesized for the visible light photoploymerization. The maximum absorption wavelengths of EATM, ECTM and PATM in DMSO were 437 nm, 455 nm and 477 nm, respectively. The fast photopolymerization of polyethylene glycol diacrylate (PEGDA) could be initiated in a three-component system consisting of photoinitiator, diphenyliodonium hexafluorophosphate (Iod) and triethanolamine (TEOA) under visible light. The conversion rate of CC bond under different light sources (405 nm, 440 nm and 480 nm) were measured by real-time Fourier transformed infrared spectroscopy (RT-FTIR). The CC bond conversion rate of PATM reached >93 % within 5 s, and the final conversion was up to 98 %, and the polymerization was completed in 10 s. The mechanism of light initiation was analyzed by density functional theory (DFT), steady-state photolysis and electron spin resonance spin trapping (ESR) experiments. Photobleaching, deep photocuring, migration ratio and cytotoxicity were evaluated. Three PIs were used to realize rapid 3D printing in an LCD 3D printer (405 nm). The printing rate was as high as 90 mm h−1 with exposure time 2 s/layer. This study provides ideas for the development of PIs for fast photopolymerization and 3D printing under visible light.

As a key acidic organelle, the pH homeostasis of lysosomes is critical for cellular functions. Existing pH fluorescent probes generally face limitations such as poor water solubility, insufficient targeting, and narrow pH response range, which hinder their practical applications in biomedical fields. In this study, a novel lysosome-targeted fluorescent probe, ANM, was designed and synthesized, which was molecularly optimized to possess excellent water solubility, precise lysosomal localization ability (P = 0.94), and a wide range of pH response properties (pH 3-8). ANM exhibits high fluorescence quantum yield (52.59%) and excellent photostability and selectivity for real-time monitoring of lysosomal pH dynamics in complex biological environments. ANM was demonstrated to be useful for visual imaging of lysosomal pH imbalance under oxidative stress and it enabled non-invasive diagnosis of gastritis in a mouse model of alcoholic gastritis by means of oral administration. This work provides a new strategy for developing diagnostic tools for pH imbalance-related diseases.

Non-isocyanate polyurethane (NIPU) has been widely considered for its green production process and sustainable development, and it is expected to be an effective substitute for traditional polyurethane. In this work, biobased five-membered cyclic carbonate was synthesized from trimethylolpropane (TMP) and glycerol (GA) at atmospheric pressure, and then NIPU with high strength, high hydrophobicity, and self-repairing was prepared by reacting cyclic carbonates with polyamines. The three-dimensional cross-linked network structure formed after curing improves the mechanical properties and thermal stability of NIPU, with tensile strengths up to 31.05 MPa. At the same time, benefiting from the dynamic covalent bonding movement and reorganization between urethane and hydroxyl groups, NIPU has a favorable self-repairing function, and the self-repairing efficiency can reach 90 %. The abundance of polar groups provides NIPU with excellent adhesion capabilities and shear strengths up to 4.02 MPa. In addition, the long-chain diamine significantly enhanced NIPU4 hydrophobicity, and the NIPU4-4 coating water contact angle was elevated to 112.65 degrees. This simple and efficient preparation method not only realizes the green preparation of NIPU at atmospheric pressure, but also overcomes the shortcomings of poor hydrophobicity and water resistance on the basis of ensuring good mechanical properties and heat resistance, which provides research ideas for the design and development of bio-based NIPU and expands its applications in building materials, furniture, electronic devices and other industries.