The synthesis of ladder-type 9,9′-bifluorenylidene-based conjugated polymer is reported. Unlike the typical synthetic strategy, the new designed ladder-type conjugated polymer is achieved via tandem ...Suzuki polymerization/Heck cyclization reaction in one-pot. In the preparation process, Suzuki polymerization reaction occurred first and then the intramolecular Heck cyclization followed smoothly under the same catalyst Pd(PPh3)4. The model reaction proved that the introduction of iodine (I) for this tandem reaction can effectively control the sequential bond-forming process and inhibit the additional competitive side reactions. Thus, small-molecule model compounds could be obtained in high yields. The successes of the synthesized small molecule and polymer compounds indicate that the Pd-catalyzed tandem reaction may be an effective strategy for improving extended π-conjugated materials.
Developing X-ray scintillators that are water-dispersible, compatible with polymeric matrices, and processable to flexible substrates is an important challenge. Herein, Tb
-doped Na
Lu
F
is ...introduced as an X-ray scintillating material with steady-state X-ray light yields of 15,800 photons MeV
, which is generated as nanocrystals on halloysite nanotubes. The obtained product exhibits good water-dispersibility and highly sensitive luminescence to X-rays. It is deposited onto a polyurethane foam to afford a composite foam material with dose-dependent radioluminescence. Moreover, the product is dispersed into polymer matrixes in aqueous solution to prepare rigid or flexible scintillator screen for X-ray imaging. As a third example, it is incorporated multilayer hydrogels for information camouflage and multilevel encryption. Encrypted information can be recognized only by X-ray irradiation, while the false information is read out under UV light. Altogether, we demonstrate that the water-dispersible scintillators are highly promising for aqueous processing of radioluminescent, X-ray imaging, and information encrypting materials.
A series of pyrene/phenanthrene‐fused furan derivatives (1–8) were synthesized by a simple condensation reaction between pyrene‐4,5‐diketone/phenanthrenequinone and substituted phenol/naphthol in the ...presence of trifluoromethanesulfonic acid in 1,2‐dichlorobenzene heated at reflux. The formed compounds can emit strong blue light in organic solvents. Additionally, the self‐assembly behaviors of two of the compounds (3 and 5) were studied through re‐precipitation method and the resulting nanostructures were characterized by UV/Vis, fluorescence spectra, and field‐emission scanning electron microscopy (FESEM). The findings showed that the shape and size of compounds 3 and 5 could be tuned by the ratio of THF and hexadecyl trimethyl ammonium bromide (CTAB) solution in water.
Fluorescent furan‐embedded heteroarenes: Eight enlarged cyclic pyrene/phenanthrene‐fused furan derivatives were synthesized through a one‐step reaction. All the resulting compounds emitted blue fluorescence in dichloromethane. The self‐assembly behaviors of two of the molecules were investigated (see figure), indicating that the shape, size, and morphology could be tuned by the ratio of THF to a solution of hexadecyl trimethyl ammonium bromide (CTAB).
Novel oral therapeutic agents based on inhibition or binding activity without adverse events in CKD patients are urgently needed. Here, 5/6 nephrectomy (NX) rats were used to construct a CKD model. ...Aminated cellulose (AC711), which is metal-free, non-absorbable, and low-volume expansive, was used as a novel oral therapeutic agent for hyperphosphataemia treatment in rats. The efficacy of AC711 on serum and urinary phosphate levels, the expression of type II sodium-dependent phosphate cotransporter (NPT2b), and type III Na-dependent phosphate cotransporter (PiT-1/2) was examined. Serum fibroblast growth factor-23 (FGF-23) levels, parathyroid hormone (PTH) levels, and the phenotypic transformation of vascular smooth muscle cell markers (smooth muscle 22 (SM22) and Runx2) are considered an adaptive response to elevated serum phosphate levels. A similar efficacy of AC711 was observed on serum and urinary phosphate levels when the same dose of AC711 and sevelamer was administered to 5/6 NX rats. The decreasing expression of NPT2b, PiT-1, and PiT-2 was examined in the AC711 groups in a dose-dependent manner. The sevelamer and AC711-MD groups for FGF-23 and PTH indicated no significant difference. The down-regulation of Runx2 expression and up-regulation of SM22 expression were seen in the AC711 groups in a dose-dependent manner. Two suppression mechanisms (binding and inhibiting activities) were observed in the gastrointestinal (GI) tract in the AC711 groups. A novel oral phosphate binder, AC711, showed both binding and inhibition characteristics. The low-volume expansion of AC711 following exposure to simulated intestinal fluid provides the potential therapeutic benefits with the advantage of moderate GI side effects.
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•A novel oral therapeutic agent AC711 is developed for treatment of hyperphosphataemia.•AC711 characters binding and inhibition activities.•AC711 is mental-free, non-absorbable, and low volume expansive.•AC711 has been demonstrated to exhibit good drug safety.
Sulfur-containing polymer supported palladium nanoparticles (Pd/SPMB) were prepared by using the cross-linked poly(N,N′-methylene bis(acrylamide)) (SPMB) as the platform. The SPMB was synthesized ...via the reversible addition–fragmentation chain transfer (RAFT) polymerization, from which the sulfur inherently exists in the RAFT polymer due to the use of thiocarbonate as the chain transfer agent, and could be further utilized as a modifier of Pd nanoparticles. The Pd/SPMB showed size-dependent activity and selectivity in the semihydrogenation of alkynes to alkenes. The catalyst with an average Pd size of 5.3 nm was active in the semihydrogenation of both internal and terminal alkynes. Most of the surface of Pd NPs was covered (or poisoned) by sulfide and thiolate due to the moderate complexation strength between Pd NPs and SPMB, thus leading to the selectivity enhancement toward alkene. Furthermore, the catalyst was highly stable and can be reused 10 times without an appreciable loss in either activity or selectivity.
The
19
F nuclear magnetic resonance (NMR) has been widely employed as a detection tool in biological studies due to its low biological background, noninvasiveness, high sensitivity, and real-time ...monitoring capability. Herein, we report a one-pot synthesis of halloysite nanotubes (HNTs) treated with benzeneboronic acids (6FBB) to afford the HNT-based
19
F NMR probe which is capable to detect the H
2
O
2
in low concentration. The product was well characterized by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The intensity of signals of
19
F was enhanced with the increasing concentration of fluorine, and the signals apparently shifted from − 62.68 to − 62.85 ppm upon the addition of H
2
O
2
. The obtained
19
F NMR probes also displayed a long spin-spin (T2) relaxation time (91.27 ms), which can strengthen image intensity. Moreover, the
19
F NMR probe exhibited non-toxic against HeLa cell. The
19
F NMR probe may serve as a desirable candidate to predict the change of H
2
O
2
in vivo.
A new family of chemical cross-linked ionogel is successfully synthesized by photopolymerization of hyperbranched aliphatic polyester with acrylate terminal groups in an ionic liquid of ...1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF₄). The microstructure, viscoelastic behavior, mechanical property thermal stability, and ionic conductivities of the ionogels are investigated systematically. The ionogels exhibit high mechanical strength (up to 1.6 MPa) and high mechanical stability even at temperatures up to 200 °C. It is found to be thermally stable up to 371.3 °C and electrochemically stable above 4.3 V. The obtained ionogels show superior ionic conductivity over a wide temperature range (from 1.2 × 10
S cm
at 20 °C up to 5.0 × 10
S cm
at 120 °C). Moreover, the Li/LiFePO₄ batteries based on ionogel electrolyte with LiBF₄ show a higher specific capacity of 153.1 mAhg
and retain 98.1% after 100 cycles, exhibiting very stable charge/discharge behavior with good cycle performance. This work provides a new method for fabrication of novel advanced gel polymer electrolytes for applications in lithium-ion batteries.
To overcome the high flammability and brittleness of epoxy resins without sacrificing their glass transition temperature (
) and mechanical properties, three epoxy-terminated hyperbranched flame ...retardants (EHBFRs) with a rigid central core and different branches, named EHBFR-HB, EHBFR-HCM, and EHBFR-HBM, were synthesized. After chemical structure characterization, the synthesized EHBFRs were introduced into the diglycidyl ether of bisphenol A (DGEBA) and cured with 4, 4-diaminodiphenylmethane (DDM). The compatibility, thermal stability, mechanical properties, and flame retardancy of the resultant resins were evaluated. Results showed that all three EHBFRs could significantly improve the fire safety of cured resins, and 30 wt. % of EHBFRs (less than 1.0 wt. % phosphorus content) endowed cured DGEBA with a UL-94 V-0 rating. In addition, the increased rigidity of branches in EHBFRs could increase the flexural strength and modulus of cured resins, and the branches with appropriate rigidity were also beneficial for improving their room temperature impact strength and
.
The development of a facile approach to simultaneously detect and separate Hg(
) ions in an aqueous solution is a challenging topic in the chemosensing field. Herein, we focus on constructing the Hg(
...)-sensitive fluorescence “turn-on”-type composite materials by using halloysite nanotube (HNT) as substrate. Two types of HNTs-based chemosensors, HNTs-PHT and HNTs-BP, were developed in this study, which exhibit Hg(
)-sensitive fluorescence “turn on” behavior by forming interparticle and intraparticle excimers, respectively. Fortunately, HNTs-PHT is able to effectively restrict the solvent relaxation of π–π* transition and make it a better detection tool in aqueous solution than HNTs-BP. The addition of Hg(
) can trigger a dramatical increase at 469 nm in emission curves of HNTs-PHT, which cannot exhibit emission behaviors without the addition of Hg(
). Furthermore, the formation of interparticle excimers makes Hg(
) serve as a crosslinker to aggregate HNTs-PHT into precipitations. Following this way, Hg(
) ions can be facilely removed from the water
a simple filtration or centrifugation approach. The as-prepared HNTs-PHT shows high specificity and precision in simultaneously detecting and separating Hg(
) without the recourse to energy consumption, which will give a novel insight to deal with heavy metal pollution.
A series of novel hyperbranched ladder-type poly(p-phenylene)s containing truxene units have been prepared through the Pd(0)-catalyzed Suzuki polymerization with an “A2 + B3” or “A2 + B2+ B3” ...approach. The polymers with different linear length show pure blue light emission from 417 to 465 nm. All the ladder-type polymers exhibit well-resolved absorption and emission spectra and small Stokes shifts in both solutions and thin films, which are the characteristics of full ladder-type poly(p-phenylene)s. The three-dimensional structures make the materials soluble in common organic solvents and able to form quality amorphous films, leading to polymer light-emitting diodes (PLEDs) with improved stability and efficiency.
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