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Zwitterionic polymer coatings facilitate the formation of hydration layers via electrostatic interactions on their surfaces and have demonstrated efficacy in preventing biofouling. They have emerged as a promising class of marine antifouling materials. However, designing multifunctional, environmentally friendly, and natural products-derived zwitterionic polymer coatings that simultaneously resist biofouling, inhibit protein adhesion, exhibit strong antibacterial properties, and reduce algal adhesion is a significant challenge. This study employed two diisocyanates as crosslinkers and natural urushiol and ethanolamine as raw materials. The coupling reaction of diisocyanates with hydroxyl groups was employed to synthesize urushiol-based precursors. Subsequently, sulfobetaine moieties were introduced into the urushiol-based precursors, developing two environmentally friendly and high-performance zwitterionic-functionalized polyurushiol antifouling coatings, denoted as HUDM-SB and IPUDM-SB. The sulfobetaine-functionalized polyurushiol coating exhibited significantly enhanced hydrophilicity, with the static water contact angle reduced to less than 60°, and demonstrated excellent resistance to protein adhesion. IPUDM-SB exhibited antibacterial efficacy up to 99.9% against common Gram-negative bacteria (E. coli and V. alginolyticus) and Gram-positive bacteria (S. aureus and Bacillus. sp.). HUDM-SB achieved antibacterial efficacy exceeding 95.0% against four bacterial species. Furthermore, the sulfobetaine moieties on the surfaces of the IPUDM-SB and HUDM-SB coatings effectively inhibited the growth and reproduction of algal cells by preventing microalgae adhesion. This zwitterionic-functionalized polyurushiol coating does not contain antifouling agents, making it a green, environmentally friendly, and high-performance biomaterial-based solution for marine antifouling.

Marine antifouling coatings that rely on the release of antifouling agents are the most prevalent and effective strategy for combating fouling. However, the environmental concerns arising from the widespread discharge of these agents into marine ecosystems cannot be overlooked. An innovative and promising alternative involves incorporating antimicrobial groups into polymers to create coatings endowed with intrinsic antimicrobial properties. In this study, we reported an urushiol-based benzoxazine (URB) monomer, synthesized from natural urushiol and antibacterial rosin amine. The URB monomer was subsequently polymerized through thermal curing ring-opening polymerization, resulting in the formation of a urushiol-based benzoxazine polymer (URHP) coating with inherent antimicrobial properties. The surface of the URHP coating is smooth, flat, and non-permeable. Contact angle and surface energy measurements confirm that the URHP coating is hydrophobic with low surface energy. In the absence of antimicrobial agent release, the intrinsic properties of the URHP coating can effectively kill or repel fouling organisms. Furthermore, with bare glass slides serving as the control sample, the coating demonstrates outstanding anti-adhesion capabilities against four types of bacteria (E. coli, S. aureus, V. alginolyticus, and Bacillus sp.), and three marine microalgae (N. closterium, P. tricornutum, and D. zhan-jiangensis), proving its efficacy in preventing fouling organisms from settling and adhering to the surface. Thus, the combined antibacterial and anti-adhesion properties endow the URHP coating with superior antifouling performance. This non-release antifouling coating represents a green and environmentally sustainable strategy for antifouling.

Oral corticosteroids represents the most prevalent treatment for idiopathic granulomatous mastitis. Ductal lavage with triamcinolone acetonide and antibiotics followed by observation (DL-OBS) has emerged as a novel strategy, but a comparison of them remains lacking. Here in this multicenter, open-label, non-inferiority, randomized trial (ClinicalTrials.gov identifier: NCT03724903), we assigned 140 patients to oral corticosteroids (N = 71) and DL-OBS (N = 69), stratified by baseline M-score. The primary outcome is complete Clinical Response rate at 1 year. The non-inferiority margin is −15%. The primary outcome is 85.5% in DL-OBS and 87.3% in oral corticosteroids (difference: −1.8%; 95%CI, 13.2 to 9.5; P non-inferiority  = .01) in intention-to-treat population, and 92.6% vs 98.2% (difference −5.6%; 95%CI −13.4 to 2.2; P non-inferiority  = .01) in per-protocol population, respectively. The most common (>15%) adverse events were Cushingoid, epigastric pain and arthralgia in oral corticosteroids, and irregular menstruation in DL-OBS, respectively. Here, we report that DL-OBS shows similar efficacy to oral corticosteroids but with better safety profile. Ductal lavage represents a treatment option for idiopathic granulomatous mastitis. Here, the authors report the results of a randomized clinical trial, indicating that ductal lavage followed by observation is non-inferior to oral corticosteroids

Raw lacquer (RLA) has been widely used indoors for centuries in Asia. But its weak UV-resistant property limited its outdoor application. In this article, the UV-resistant property of lacquer film was significantly improved by solution intercalation method. The intercalated nanocomposites were obtained from RLA, multihydroxyl polyacrylate resin (MPA), and organophilic montmorillonite (OMMT). The structure and morphology of the RLA/MPA/OMMT nanocomposites were confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The variation of the film gloss and impact strength with different UV exposure time was also investigated. Owing to the dispersion of nanometer-sized OMMT in polymer matrix, the RLA/MPA/OMMT nanocomposites exhibited improved UV-resistant property. When the OMMT content is 3.0 wt%, the best physical–mechanical properties can be obtained. These results indicated that the solution intercalation with nanoparticles was an efficient and convenient method to improve the properties of raw lacquer.

Benzoxazine resins are new thermosetting resins with excellent thermal stability, mechanical properties, and a flexible molecular design, demonstrating promise for applications in marine antifouling coatings. However, designing a multifunctional green benzoxazine resin-derived antifouling coating that combines resistance to biological protein adhesion, a high antibacterial rate, and low algal adhesion is still challenging. In this study, a high-performance coating with a low environmental impact was synthesized using urushiol-based benzoxazine containing tertiary amines as the precursor, and a sulfobetaine moiety into the benzoxazine group was introduced. This sulfobetaine-functionalized urushiol-based polybenzoxazine coating (poly(U−ea/sb)) was capable of clearly killing marine biofouling bacteria adhered to the coating surface and significantly resisting protein attachment. poly(U−ea/sb) exhibited an antibacterial rate of 99.99% against common Gram negative bacteria (e.g., Escherichia coli and Vibrio alginolyticus) and Gram positive bacteria (e.g., Staphylococcus aureus and Bacillus sp.), with >99% its algal inhibition activity, and it effectively prevented microbial adherence. Here, a dual-function crosslinkable zwitterionic polymer, which used an “offensive-defensive” tactic to improve the antifouling characteristics of the coating was presented. This simple, economic, and feasible strategy provides new ideas for the development of green marine antifouling coating materials with excellent performance.

Marine anti-fouling coatings represent an efficient approach to prevent and control the marine biofouling. However, a significant amount of antifouling agent is added to improve the static antifouling performance of the coatings, which leads to an issue whereby static antifouling performance conflicts with eco-friendly traits. Herein, this work reports an in situ reduction synthesis of silver nanoparticles (AgNPs) within polymers to produce composite coatings, aiming to solve the aforementioned issue. Firstly, urushiol-based benzoxazine monomers were synthesized by the Mannich reaction, using an eco-friendly natural product urushiol and n-octylamine and paraformaldehyde as the reactants. Additionally, AgNPs were obtained through the employment of free radicals formed by phenolic hydroxyl groups in the urushiol-based benzoxazine monomers, achieved by the in situ reduction of silver nitrate in benzoxazine. Then, the urushiol-based benzoxazine/AgNPs composite coatings were prepared by the thermosetting method. AgNPs exhibit broad-spectrum and highly efficient antimicrobial properties, with a low risk to human health and a minimal environmental impact. The composite coating containing a small amount of AgNPs (≤1 wt%) exhibits effective inhibition against various types of bacteria and marine microalgae in static immersion, thereby displaying outstanding antifouling properties. This organic polymer and inorganic nanoparticle composite marine antifouling coating, with its simple preparation method and eco-friendliness, presents an effective solution to the conflict between static antifouling effectiveness and environmental sustainability in marine antifouling coatings.

Ionic conductive hydrogels have attracted increasing research interest in flexible electronics. However, the limited resilience and poor fatigue resistance of current ionic hydrogels significantly restrict their practical application. Herein, an urushiol-based ionic conductive double network hydrogel (PU/PVA-Li) was developed by one-pot thermal initiation polymerization assisted with freeze–thaw cycling and subsequent LiCl soaking. Such a PU/PVA-Li hydrogel comprises a primary network of covalently crosslinked polyurushiol (PU) and a secondary network formed by physically crosslinked poly(vinyl alcohol) (PVA) through crystalline regions. The obtained PU/PVA-Li hydrogel demonstrates exceptional mechanical properties, including ultrahigh strength (up to 3.4 MPa), remarkable toughness (up to 1868.6 kJ/m3), and outstanding fatigue resistance, which can be attributed to the synergistic effect of the interpenetrating network structure and dynamic physical interactions between PU and PVA chains. Moreover, the incorporation of LiCl into the hydrogels induces polymer chain contraction via ionic coordination, further enhancing their mechanical strength and resilience, which also impart exceptional ionic conductivity (2.62 mS/m) to the hydrogels. Based on these excellent characteristics of PU/PVA-Li hydrogel, a high-performance flexible strain sensor is developed, which exhibits high sensitivity, excellent stability, and reliability. This PU/PVA-Li hydrogel sensor can be effectively utilized as a wearable electronic device for monitoring various human joint movements. This PU/PVA-Li hydrogel sensor could also demonstrate its great potential in information encryption and decryption through Morse code. This work provides a facile strategy for designing versatile, ultrastrong, and tough ionic conductive hydrogels using sustainable natural extracts and biocompatible polymers. The developed hydrogels hold great potential as promising candidate materials for future flexible intelligent electronics.

Soluble conjugated aromatic poly(1,3-dialkoxybenzene)s were obtained in high yield up to 80% in 30 min by grinding 1,3-dialkoxybenzene with anhydrous FeCl 3 powder in a mortar at ambient and solvent-free condition. The polymers were characterized by FT-IR, 1 H-NMR, 13 C-NMR, and gel permeation chromatography. The structure of the aromatic rings linkage at meta-position was confirmed. Thermogravimetric analysis, UV–Vis, fluorescence spectroscopy, and four-probe a.c. technique were used to probe the thermal, optical, and electrical properties of the polymers. The polymers displayed high thermostability with the decomposition temperatures at about 382–388 °C. The optical energy gap ( E g ) of the polymers was 4.23 eV and electrical conductivity at room temperature was 10 −6  S cm −1 . The fluorescence curve of the polymers displayed the maximum at 344 nm in CH 2 Cl 2 solution. The morphology of the polymers was determined by X-ray diffraction and scanning electron microscope technique.

Nanocellulose hydrogels are a crucial category of soft biomaterials with versatile applications in tissue engineering, artificial extracellular matrices, and drug-delivery systems. In the present work, a simple and novel method, involving the self-assembly of cellulose nanocrystals (CNCs) induced by tannic acid (TA), was developed to construct a stable hydrogel (SH-CNC/TA) with oriented porous network structures. The gelation process is driven by the H-bonding interaction between the hydroxyl groups of CNCs and the catechol groups of TA, as substantiated by the atoms in molecules topology analysis and FTIR spectra. Interestingly, the assembled hydrogels exhibited a tunable hierarchical porous structure and mechanical moduli by varying the mass ratio of CNCs to TA. Furthermore, these hydrogels also demonstrate rapid self-healing ability due to the dynamic nature of the H-bond. Additionally, the structural stability of the SH-CNC/TA hydrogel could be further enhanced and adjusted by introducing coordination bonding between metal cations and TA. This H-bonding driven self-assembly method may promote the development of smart cellulose hydrogels with unique microstructures and properties for biomedical and other applications.

Anti-corrosion coatings often fail due to aging effects. Therefore, taking advantage of the positive effects of multilayer structure of α-zirconium phosphate (α-ZrP) on the anti-aging properties of coatings, organic–inorganic composite materials based on α-ZrP were synthesized. Firstly, α-ZrP was synthesized by a hydrofluoric acid precipitation method. Then, CT-ZrP was prepared by α-ZrP, pre-intercalated successively with cholamine and cetyltrimethylammonium bromide (CTAB). The synthesized CT-ZrP was then used for synthesizing urushiol-titanium polymer/ZrP composite coatings (M-ZrP) through intercalation. The results of XRD, TEM, and FTIR proved the successful intercalation of α-ZrP and the loss of layering M-ZrP composite coatings in the process of exfoliation. TG results showed that the thermal stability of M-ZrP3 (3 wt% CT-ZrP) was higher than that of urushiol-titanium polymer (UTP). After 1000 h of accelerated aging, 3 wt% of CT-ZrP could significantly improve the anti-aging property of the UTP coating, and the maximum rate of gloss loss was the lowest (5.9%).