Efficient synthesis of poly(enamine)s has been a great challenge because of their poor stability, poor solubility, and low molecular weights. In this work, a spontaneous amino-yne click polymerization for the efficient preparation of poly(enamine)s was established, which could proceed with 100% atom efficiency under very mild conditions without any external catalyst. Through systematic optimization of the reaction conditions, several soluble and thermally stable poly(β-aminoacrylate)s with high molecular weights (M up to 64400) and well-defined structures were obtained in excellent yields (up to 99%). Moreover, the polymerization can perform in a regio- and stereospecific fashion. Nuclear magnetic resonance spectra analysis revealed that solely anti-Markovnikov additive products with 100% E-isomer were obtained. The reaction mechanism was well demonstrated with the assistance of density functional theory calculations. In addition, by introducing the tetraphenylethene moiety, the resulting polymers exhibit unique aggregation-induced emission characteristics and could be applied in explosives detection and bioimaging. This polyhydroamination is a new type of click polymerization and opens up enormous opportunities for preparing functional polymeric materials.
Graphene oxide (GO) is emerging as a potential adsorbent for environmental cleanup due to its attractive attributes associated with high removal efficiency toward water pollutants. However, it is difficult to separate GO from water after adsorption. Until now, the development of an effective approach that can simultaneously take advantage of the adsorption feature of GO and overcome the separation problem is still a challenge. Herein, we demonstrate a simple one-step approach to fabricate magnetic GO/poly(vinyl alcohol) (PVA) composite gels (mGO/PVA CGs), which not only exhibit convenient magnetic separation capability but also show remarkably enhanced adsorption capacity for cationic methylene blue (MB) and methyl violet (MV) dyes as compared with the one without GO (e.g., the adsorption capacities of mGO/PVA-50% and mGO/PVA-0% for MB are 231.12 and 85.64 mg/g, respectively). Detailed adsorption studies reveal that the adsorption kinetics and isotherms can be well-described by pseudo-second-order model and Langmuir isotherm model, respectively. Moreover, the adsorbent could be well regenerated in an acid solution without obvious compromise of removal efficiency. Considering the facile fabrication process and robust adsorption performance of the mGO/PVA CG, this work opens up enormous opportunities to bring GO from experimental research to practical water treatment applications. In addition, the mGO/PVA CG can act as a magnetic support for in situ growth of noble metal nanocatalyst with excellent catalytic performance, as exemplified by the synthesis of mGO/PVA-Pt catalyst in this paper.
The unique advantages and the exciting application prospects of AIEgens have triggered booming developments in this area in recent years. Among them, stimuli‐responsive AIEgens have received particular attention and impressive progress, and they have been demonstrated to show tremendous potential in many fields from physical chemistry to materials science and to biology and medicine. Here, the recent achievements of stimuli‐responsive AIEgens in terms of seven most representative types of stimuli including force, light, polarity, temperature, electricity, ion, and pH, are summarized. Based on typical examples, it is illustrated how each type of systems realize the desired stimuli‐responsive performance for various applications. The key work principles behind them are ultimately deciphered and figured out to offer new insights and guidelines for the design and engineering of the next‐generation stimuli‐responsive luminescent materials for more broad applications.
Two-dimensional layered MoS 2 nanosheets exhibit a wide range of attractive properties and hold great promise in myriad fields. However, the poor performance of surface functionality greatly limits their applications. In this paper, we report on a facile approach to direct synthesis of organic functional group decorated MoS 2 (OFGD-MoS 2 ) nanosheets based on the simultaneous exfoliation of bulk MoS 2 crystals and chemical conjugation of thiol ligands. The morphology and structure of OFGD-MoS 2 nanosheets are systematically characterized using microscopy (TEM, SEM, AFM), thermal gravimetric analysis (TGA), and spectroscopy (Raman, FTIR, XPS) measurements. The content of attached functional groups can be controlled simply by changing the experimental conditions. Furthermore, the introduced functional groups show excellent structural stability and high chemical reactivity, making them promising for further modification as confirmed by the in situ growth of inorganic nanoparticles and polymers. In addition, surface functionalized WS 2 nanosheets can also be synthesized by this approach. This investigation paves the way for the synthesis and applications of advanced MoS 2 -based materials.
Constructing artificial helical structures through hierarchical self-assembly and exploring the underlying mechanism are important, and they help gain insight from the structures, processes, and functions from the biological helices and facilitate the development of material science and nanotechnology. Herein, the two enantiomers of chiral Au(I) complexes ( S )-1 and ( R )-1 were synthesized, and they exhibited impressive spontaneous hierarchical self-assembly transitions from vesicles to helical fibers. An impressive chirality inversion and amplification was accompanied by the assembly transition, as elucidated by the results of in situ and time-dependent circular dichroism spectroscopy and scanning electron microscope imaging. The two enantiomers could serve as ideal chiral templates to co-assemble with other achiral luminogens to efficiently induce the resulting co-assembly systems to show circularly polarized luminescence (CPL). Our work has provided a simple but efficient way to explore the sophisticated self-assembly process and presented a facile and effective strategy to fabricate architectures with CPL properties.
A facile and green approach for the synthesis of amphibious fluorescent carbon dots (CDs) from natural polysaccharide is reported. Light-emitting polymer nanocomposites with excellent optical performance can be easily prepared by incorporation of the amphibious CDs into the polymer matrix.
In this paper, a facile one-pot strategy for scalable synthesis of robust magnetic poly(vinyl alcohol) (mPVA) gel beads is developed. Through dropwise addition of mixed aqueous solution of iron salts and PVA solution into alkaline (e.g., ammonia, NaOH, and KOH) solution, mPVA gel beads with uniform size and excellent superparamagnetic property can be fabricated based on the simultaneous formation of magnetic iron oxide nanoparticles (MIONs) and cross-link of PVA chains. Moreover, this approach can be extended to prepare dual- or multiresponsive gel beads through simply adding functional fillers into PVA solution (e.g., mPVA-PNIPAM gel beads that possess both magnetic and temperature responsibilities can be readily prepared by adding temperature responsive poly(N-isopropylacrylamide) (PNIPAM) into PVA solution). It is found that that the obtained mPVA gel beads exhibit high drug loading level (e.g., above 70%) after the treatment of freezing-thawing. Drug release experiments reveal that the drug release rate and amount of the mPVA gel beads can be tuned by operating the external magnetic field and adjusting the concentration of iron oxide nanoparticles and temperature (for mPVA-PNIPAM gel beads). The present work is of interest for opening up enormous opportunities to make full use of magnetic gel beads in drug delivery and other applications, because of their facile availability, cost-effective productivity, and tunable drug release performance.
Inspired by the respective advantages of aggregation‐induced emission (AIE)‐active photosensitizers and black phosphorus nanomaterials in cancer treatment, the facile construction of novel AIE photosensitizers married to 2D black phosphorus nanosheets and their application for multimodal theranostics are demonstrated. The developed nanomaterial simultaneously possesses distinctive properties and multiple functions including excellent stability, good biocompatibility, intensive fluorescence emission in the NIR region, high‐performance reactive oxygen species generation, good photothermal conversion efficiency, outstanding cellular uptake, and effective accumulation at the tumor site. Both in vitro and in vivo evaluation show that the presented nanotheranostic system is an excellent candidate for NIR fluorescence–photothermal dual imaging‐guided synergistic photodynamic–photothermal therapies. This study thus not only extends the applications scope of AIE and black phosphorus materials, but also offers useful insights into designing a new generation of cancer theranostic protocol for potential clinical applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.