Polymeric ultralong organic phosphorescence with excellent humidity and temperature resistance via hydrophobic effect

Polymeric ultralong organic phosphorescence(UOP)with persistent emission is of great importance in practical applications.However,achieving good water-resistance for long-term environmental stability is a formidable challenge.In this contribution,through tailoring the alkyl-chain length of the hardeners and emitters,polymeric UOPs with varying crosslinking density and hydrophobic effect were obtained.Notably,all the polymers show no obvious decrease in UOP emission after high temperature-humidity test(85◦C/85%relative humidity for 7 days).Detailed investigations demonstrate that the rigid covalent crosslinking networks suppress the quenching of triplet excitons while the hydrophobic microenvironment affords good water/moisture-resistance ability.Moreover,the polymers with superior processability are successfully applied as optical coatings,prepreg,and afterglow displays.With this work,we provide a new strategy to promote the long-term stability of polymeric UOP materials in high-temperature-humidity conditions.

Thermoresponsive Fluorescent Semicrystalline Polymers Decorated with Aggregation Induced Emission Luminogens

Thermoresponsive fluorescent polymers(TFPs) with unique temperature-dependent luminescent properties are of great importance for the development of new functional devices in recent years. Herein, we facilely synthesized an efficient blue-emissive polymer, abbreviated as PCB-TPE, using tetraphenylethene(TPE) as the main building block. PCB-TPE is thermally stable with a novel property of aggregation induced emission(AIE). The thermoresponsive property and mechanism of PCB-TPE were investigated. Its emission shows temperature-dependent features and reveals fine details in the thermal transitions from-10 °C to 60 °C. The polymer offers a platform for the development of efficient luminescent materials for further biological and optoelectronic applications.

Investigation on Viscoelasticity of Waterborne Polyurethane with Azobenzene-containing Pendant Groups under Ultraviolet and Visible-light Irradiation

In this study,a novel waterborne polyurethane(WPU)with azobenzene-containing(azo-containing)pendant groups was synthesized by isophorone diisocyanate,long-chain diol of polycaprolactone,2-ethyl-2-methyl-butanoic acid(2,2-dimethylolpropionic acid),10-(4-(phenyldiazenyl)phenoxy)decyl-3-hydroxy-2-(hydroxymethyl)-2-methylpropanoate,and N,N-diethyl-ethanamine(triethylamine).Moreover,the influence of ultraviolet and visible(UV-Vis)light irradiation on the viscoelasticity of azo-containing WPU film in terms of the reversible trans-cis photoisomerization of azo-containing pendant groups was investigated by UV-Vis light spectroscopy,atomic force microscopy,and dynamic thermomechanical analysis.The results revealed that the adhesion of azo-containing WPU with single crystal silicon atomic force microscope probe was about 13 n N when irradiated by 450 nm Vis light for 60 s at 25°C.Subsequently,the adhesion increased to 82 n N after irradiation with 365 nm UV light for 60 s at 25°C.In addition,the azo-containing WPU presented a photo-induced reversible transition of tensile modulus and tanδin the range from about 2 MPa to 22 MPa and 6000 to 0.35 with UV-Vis light cyclic irradiation for 120 s at 25°C,respectively.

Fabrication of Silver Yolk@Porous Janus Polymer Shell Nanospheres for Synergistic Catalysis

Yolk-shell nanostructures have recently attracted tremendous research interests in various areas because of their unique structural merits.Currently,there is an urgent need for developing porous shells with multifunctional features to enhance their performance in various applications.Herein,advanced yolk-shell nanospheres have been facilely prepared by encapsulating silver nanoparticles with porous Janus polymer shells that consist of a hypercrosslinked polystyrene(xPS)outer layer and a tethered poly(acrylic acid)(PAA)brush lining.The xPS outer layer possesses well-developed porosity as mass diffusion pathways.More importantly,the tethered PAA brushes with customized carboxyl groups exhibit great affinity toward specific species(e.g.,cationic dyes),leading to their enrichment from the bulk solution into the interior cavity.The unusual combination of highly porous outer layers with customizable inbuilt polymer linings in the porous Janus shells endows them with great promise for synergistically catalytic degradation of cationic dyes.

Inhibition of osteosarcoma growth and metastasis using a polysaccharide derivative of Amy-g-PLLD for the delivery of AEG-1 siRNA

Osteosarcoma is the most common primary malignant neoplasm of the bone in children and adolescents and has a high risk of relapse and metastasis. Of the various methods to treat osteosarcoma, the use of genetic approaches to inhibit the rapid growth of osteosarcoma while limiting tumor metastasis has presented a challenge in its implementation. Here, we successfully synthesized a polysaccharide derivative （Amy-g-PLLD） for delivery of astrocyte elevated gene-1 （AEG-1） small-interfering RNA （siRNA） （siAEG-1）, and used it for the first time to suppress osteosarcoma tumors in vitro and in vivo. Amy-g-PLLD/ siAEG-1 complexes were delivered into 143B human osteosarcoma cells with low resultant cytotoxicity. Osteosarcoma tumor proliferation and invasion were inhibited in vitro. Intratumoral injection of Amy-g-PLLD/siAEG-1 complexes markedly inhibited tumor growth and lung metastasis in 143B tumor-bearing mice. This biocompatible and effective approach employing a natural material- siRNA complex should pave the way for more genetic research in treating osteosarcoma.

Sulfonyldibenzene-based hole-transporting materials for efficient n-i-p perovskite solar cells

Organic hole-transporting materials(HTMs)are an essential component in conventional perovskite solar cells(PSCs).In this work,two sulfonyldibenzene-based molecules,named CS-04 and CS-05,are synthesized and employed as HTMs in n-i-p PSCs.In comparison with CS-04,the carbazole-substituted methoxytriphenylamine(Cz MOTPA)group in CS-05 exhibits an increased degree of molecular distortion,thus endowing CS-05 with excellent solvent solubility and film-formation ability.Moreover,CS-05 shows a high hole mobility,superior hole extraction and hole transporting properties.As a result,CS-05 yields impressive device performances with a high power conversion efficiency(PCE)of 20.15%,while that of CS-04 based device is 19.50%,which is comparable to that of the Spiro-OMe TAD based control device(19.59%).This finding illustrates the potential of sulfonyldibenzene-based molecules for the applications in PSCs,and also provides a novel avenue to improve the performances and stability of PSCs by tailoring the sulfonyldibenzene-based molecules.

Metallophilicity-Induced Clusterization:Single-Component White-Light Clusteroluminescence with Stimulus Response

Materials showing metallophilic interactions continue to attract considerable theoretical and experimental attention largely because of their unusual and unanticipated photophysical behavior as well as their unique stimuli-responsive behavior in an aggregate or solid state.Metallophilic interactions are mostly found between metals with either identical(d^(10)–d^(10))or different(s^(2)–d^(8),d^(8)–d^(10))configurations.Among various metallophilic interactions,aurophilic interactions(Au⋯Au)are well-known and widely reported.In this study,a new phosphorescent gold(I)complex,[(CF_(3)Ph)_(3)PAuC≡CPh](TPPGPA)was reported.

Achieving Bright Mechanoluminescence in a Hydrogen-Bonded Organic Framework by Polar Molecular Rotor Incorporation

Luminescent hydrogen-bonded organic frameworks(HOFs)have attracted increasing attention due to their corresponding luminescence that enables readily visualization of structural dynamics.HOFs with the mechanoluminescence(ML)property can emit light without photon excitation and are greatly attractive for advanced applications,but research in this area has been limiting.Herein,we report the first example of an ML-active flexible HOF with permanent porosity,named 8PCOM,assembled from polar molecular rotors with an aggregation-induced emission property.When responding to different solvent vapors,reversible structural transformations between ML-active and-inactive 8PCOM frameworks occur,including a single-crystal-to-single-crystal(SCSC)transformation.Thus,guest-induced breathing behaviors are mainly attributed to phenyl rotations of polar molecular rotors induced by external stimuli.During reversible structural transformations of various 8PCOM frameworks with different pores,the significant ML property is achieved successfully through supramolecular dipole moment regulation.Upon mechanical force,bright emission of the ML-active 8PCOM framework is observed without UV irradiation,and the ML-active crystals can be easily prepared and regenerated.This work not only provides a valuable strategy for engineering future multifunctional HOFs but also enriches the types and applications of existing luminescent porous materials.