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 共查询到20条相似文献,搜索用时 15 毫秒
1.
The first polymer bearing exTTF units intended for the use in electrical charge storage is presented. The polymer undergoes a redox reaction involving two electrons at −0.20 V vs Fc/Fc+ and is applied as active cathode material in a Li‐organic battery. The received coin cells feature a theoretical capacity of 132 mAh g−1, a cell potential of 3.5 V, and a lifetime exceeding more than 250 cycles.

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2.
A series of fluorene‐based conjugated polymers containing the aggregation‐induced emissive (AIE)‐active tetraphenylethene and dicarboxylate pseudocrown as a receptor exhibits a unique dual‐mode sensing ability for selective detection of lead ion in water. Fluorescence turn‐off and turn‐on detections are realized in 80%–90% and 20% water in tetrahydrofuran (THF), respectively, for lead ion with a concentration as low as 10−8 m .

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3.
Electrohydrodynamic cojetting has been employed to synthesize compartmentalized microfibers from thermally responsive hydrogels. The synthesis of the hydrogels as well as their transformation into compartmentalized microcylinders is discussed. After programmable shape‐shifting, snail‐like particles are obtained that undergo functional and structural reconfiguration in response to a change in temperature.

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4.
Novel supramolecular phosphorescent polymers (SPPs) are synthesized as a new class of solution‐processable electroluminescent emitters. The formation of these SPPs takes advantage of the efficient non‐bonding assembly between bis(dibenzo‐24‐crown‐8)‐functionalized iridium complex monomer and bis(dibenzylammonium)‐tethered co‐monomer, which is monitored by 1H NMR spectroscopy and viscosity measurements. These SPPs show good film morphology and an intrinsic glass transition with a Tg of 94–116 °C. Noticeably, they are highly photoluminescent in solid state with quantum efficiency up to ca. 78%. The photophysical and electroluminescent properties are strongly dependent on the molecular structures of the iridium complex monomers.

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5.
Diselenide‐containing polymers are facilely synthesized from polymers prepared by atom transfer radical polymerization (ATRP). Benefiting from the ATRP technology, this protocol provides a flexible route for controlling the polymer structure, which allows for a great variety of architectures of selenium‐containing polymer materials for applications in various fields. The oxidative and reductive responsive behavior of the obtained diselenide‐containing polymers is also investigated.

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6.
The chemical control of cell division has attracted much attention in the areas of single cell‐based biology and high‐throughput screening platforms. A mussel‐inspired cytocompatible encapsulation method for achieving a “cell‐division control” with cross‐linked layer‐by‐layer (LbL) shells is developed. Catechol‐grafted polyethyleneimine and hyaluronic acid are chosen as polyelectrolytes for the LbL process, and the cross‐linking of polyelectrolytes is performed at pH 8.5. Cell division is controlled by the number of the LbL nanolayers and cross‐linking reaction. We also suggest a new measuring unit, , for quantifying “cell‐division timing” based on microbial growth kinetics.

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7.
A simple and effective airflow method to prepare sandwich‐type block copolymer films is reported. The films are composed of three layers: vertically oriented nanocylinders align in both upper and bottom layers and irregular nanocylinders exist in the bulk of the film. The vertically oriented nanocylinders in both sides can provide high accessibility to ions and ensures the exchange of chemical species between the membrane and external environment, while the irregularly oriented nanocylinders in the middle part of the film can prolong the pathway of ions transportation and enhance ions selectivity.

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8.
A facile and versatile approach to constructing colorless surface coatings based on green tea polyphenols is reported, which can further act as a photoinitiating layer to initiate radical polymerization. These colorless green tea polyphenol coatings are capable of successfully photografting polymer brushes, and the resulting polymer brush patterns show spatial shape adjustability by masked UV irradiation. Both surface modifications and photografted polymer brushes do not alter the original color of the substrates. This method could be promising for the development of surface modifications.

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9.
The glucose oxidase and glucose mediated formation of amphipilic copolymers of N‐(ferrocenoylmethyl)acrylamide (NFMA) and N,N‐diethylacrylamide (DEA) in aqueous cyclodextrin solution is presented. Thereby, NFMA is not only a comonomer but also part of the redox initiation system. The obtained copolymers contain NFMA units between 1 and 10 mol%. The molecular masses of the copolymers are dependent on the ferrocene content, whereupon molecular weights between 38 000 and 71 000 g mol−1 are achieved.

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10.
The synthesis of highly efficient two‐photon uncaging groups and their potential use in functional conjugated polymers for post‐polymerization modification are reported. Careful structural design of the employed nitrophenethyl caging groups allows to efficiently induce bond scission by a two‐photon process through a combination of exceptionally high two‐photon absorption cross‐sections and high reaction quantum yields. Furthermore, π‐conjugated polyfluorenes are functionalized with these photocleavable side groups and it is possible to alter their emission properties and solubility behavior by simple light irradiation. Cleavage of side groups leads to a turn‐on of the fluorescence while solubility of the π‐conjugated materials is drastically reduced.

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11.
A novel and non‐cytotoxic self‐healing supramolecular elastomer (SE) is synthesized with small‐molecular biological acids by hydrogen‐bonding interactions. The synthesized SEs behave as rubber at room temperature without additional plasticizers or crosslinkers, which is attributed to the phase‐separated structure. The SE material exhibits outstanding self‐healing capability at room temperature and essential non‐cytotoxicity, which makes it a potential candidate for biomedical applications.

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12.
Five three‐component chiral polymers incorporating (S )‐1,1′‐binaphthyl, tetraphenylethene (TPE) and fluorene moieties are designed and synthesized by Pd‐catalyzed Sonogashira reaction. All these polymers show obvious aggregation induced emission enhancement response behavior in the fluorescence emission region of 460–480 nm. Interestingly, three of them show aggregation‐induced circularly polarized luminescence (AICPL) signals in tetrahydrofuran–H2O mixtures. Most importantly, these AICPL signals can be tuned by changing the molar ratios of TPE and fluorene components through fluorescence resonance energy transfer and give the highest glum = ±4.0 × 10−3. This work provides a novel strategy for developing AICPL‐enhanced materials.

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13.
Novel macrocyclic amine‐linked oligocarbazole hollow microspheres are synthesized via a one‐step oxidative method in aqueous solution. Upon altering the oxidants and acidic media, the average diameters of the obtained hollow microspheres are tunable from 0.23 to 2.0 μm. With attractive amine and carbazole functionalities, exposed surface area, thermostability, and photoluminescent properties, the amine‐linked oligocarbazole hollow microspheres are directly assembled to yield heavy metal sorbents with excellent selectivity and recyclability, shown to efficiently remove lead from contaminated water.

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14.
The ruthenium benzimidazolylidene‐based N‐heterocyclic carbene (NHC) complex 4 catalyzes the direct dehydrogenative condensation of primary alcohols into esters and primary alcohols in the presence of amines to the corresponding amides in high yields. This efficient new catalytic system shows a high selectivity towards the conversion of diols to polyesters and of a mixture of diols and diamines to polyamides. The only side product formed in this reaction is molecular hydrogen. Remarkable is the conversion of hydroxytelechelic polytetrahydrofuran ( = 1000 g mol−1)—a polydispers starting material—into a hydrolytically degradable polyether with ester linkages ( = 32 600 g mol−1) and, in the presence of aliphatic diamines, into a polyether with amide linkages in the back bone ( = 16 000 g mol−1).

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15.
Vinyl acetate is polymerized in the living way under the irradiation of blue light‐emitting diodes (LEDs) or sunlight without photocatalyst at ambient temperature. 2‐(Ethoxycarbonothioyl)sulfanyl propanoate is exclusively added and acts as initiator and chain transfer agent simultaneously in the current system. Poly(vinyl acetate) with well‐regulated molecular weight and narrow molecular weight distribution (Đ < 1.30) is synthesized. Near quantitative end group fidelity of polymer is demonstrated by nuclear magnetic resonance (NMR) and matrix‐assisteed laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS).

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16.
The polymerisation of N‐acryloylmorpholine in water is reported utilising Cu(0)‐mediated living radical polymerisation (SET‐LRP). The inherent instability of [CuI(Me6‐Tren)Br] in aqueous solution is exploited via rapid disproportionation to prepare Cu(0) particles and [CuII(Me6‐Tren)Br2] in situ prior to addition of monomer and initiator. Quantitative conversion is attained within 30 min for various degrees of polymerisation (DPn = 20–640) with SEC showing symmetrical narrow molecular weight distributions (Đ < 1.18) in all cases. Optimised conditions are subsequently applied for the preparation of a diblock copolymer poly(NIPAm)‐b‐(N‐acryloylmorpholine), illustrating the versatility of this approach.

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17.
The controlled folding of a single polymer chain is for the first time realized by metal‐ complexation. α,ω‐Bromine functional linear polymers are prepared via activators regenerated by electron transfer (ARGET) ATRP (,SEC = 5900 g mol−1, Đ = 1.07 and 12 000 g mol−1, Đ = 1.06) and the end groups of the polymers are subsequently converted to azide functionalities. A copper‐catalyzed azide–alkyne cycloaddition (CuAAC) reaction is carried out in the presence of a novel triphenylphosphine ligand and the polymers to afford homotelechelic bis‐triphenylphosphine polymeric‐macroligands (MLs) (,SEC = 6600 g mol−1, Đ = 1.07, and 12 800 g mol−1, Đ = 1.06). Single‐chain metal complexes (SCMCs) are formed in the presence of Pd(II) ions in highly diluted solution at ambient temperature. The results derived via 1H and 31P{1H} NMR experiments, SEC, and DLS unambiguously evidence the efficient formation of SCMCs via metal ligand complexation.

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18.
Polymeric nanosheets organized by molecular building blocks bearing specifically oriented reactive groups provide abundant and versatile strategies for tailoring structure and chemical functionality periodically over extended length scales that complement graphene. Here we report the bulk synthesis of free‐standing polymeric nanosheets via spatially confined polymerization from an elaborate 2D supramolecular system composed of two liquid‐crystalline lamellar bilayer membranes of a self‐assembled nonionic surfactant—dodecylglyceryl itaconate (DGI)—sandwiched by a water layer. By employing a covalent polymerization on the lamellar bilayer membranes, single‐bilayer‐thick (4.2 nm), and large area (greater than 100 μm2) polymeric nanosheets of bilayer membranes are achieved. The polymeric nanosheets could serve as a well‐defined 2D platform for post‐functionalization for producing advanced hybrid materials by introducing the reactions on the hydroxyl groups at the head of DGI on the outer surfaces.

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19.
Halo‐ester‐functionalized poly(ethylene glycol)s (PEGs) are successfully prepared by the transesterification of alkyl halo‐esters with PEGs using Candida antarctica lipase B (CALB) as a biocatalyst under the solventless conditions. Transesterifications of chlorine, bromine, and iodine esters with tetraethylene glycol monobenzyl ether (BzTEG) are quantitative in less than 2.5 h. The transesterification of halo‐esters with PEGs are complete in 4 h. 1H and 13C NMR spectroscopy with MALDI‐ToF and ESI mass spectrometry confirm the structure and purity of the products. This method provides a convenient and “green” process to effectively produce halo‐ester PEGs.

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20.
A new approach is reported for the preparation of a graphene–epoxy flexible transparent capacitor obtained by graphene–polymer transfer and UV‐induced bonding. SU8 resin is employed for realizing a well‐adherent, transparent, and flexible supporting layer. The achieved transparent graphene/SU8 membrane presents two distinct surfaces: one homogeneous conductive surface containing a graphene layer and one dielectric surface typical of the epoxy polymer. Two graphene/SU8 layers are bonded together by using an epoxy photocurable formulation based on epoxy resin. The obtained material showed a stable and clear capacitive behavior.

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