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A novel dynamic covalent gel has been prepared via the imine bond formation reaction of tetraamine building blocks with luminescent tetraphenylethene tetraaldehyde units. The gel shows high hierarchical porosity (SBET = 512 m² g-1) and remarkable aggregation-induced emission enhancement, which has been demonstrated to be a selective sensor. Dynamic covalent [ABSTRACT FROM AUTHOR]

Novel fluorescent nanoparticle (FNP)-based bioprobes are expected to generate new medical diagnostic techniques in biomedical and biological areas for their superior brightness and photostability compared with conventional molecular probes including small organic dyes and fluorescent proteins. Potentially interesting nanoscale platforms for various biomedical applications are greatly attractive due to the potential to avoid exposure of human tissues to toxic drugs, enhancing delivery of hydrophobic therapeutics and fabricating multifunctional imaging, targeting and delivery system. In this review, recent progress in the area of novel aggregation induced emission (AIE)-based FNPs is summarized over the past few years (2007 -- 2013), and the reported fabrication methodologies of these fluorescent systems including non-covalent and covalent strategies are mainly discussed, and the biomedical applications of AIE-based FNPs are also summarized. [ABSTRACT FROM AUTHOR]

A novel luminophore TPENSOH was facilely synthesized from the building blocks of tetraphenylethylene and 6-hydroxylbenzothiazole and exhibited unique AIE properties. This new dye was found to show a remarkable and reversible four-color switching based on a single molecule in the solid state. [ABSTRACT FROM AUTHOR]

Novel thermally conductive, insulated polyimide nanocomposite films are reported here for microelectronics applications. A thermally conductive, insulated inorganic nanolayer of AlO(OH) was successfully coated onto the surface of MWCNTs, which, on the one hand, can effectively avoid the formation of MWCNT electrically conductive networks in the PI matrix and, on the other, can provide the advantage of excellent thermal conductivity properties of the MWCNTs. [ABSTRACT FROM AUTHOR]

The phase stability and melting behavior of nylon 6 were studied by high-temperature wide-angle X-ray diffraction and differential scanning calorimetry (DSC). The results show that most of the α phase obtained by a solution-precipitation process [nylon 6 powder (Sol-Ny6)] was thermodynamically stable and mainly melted at 221°C; the double melting peaks were related to the melt of α crystals with different degrees of perfection. The γ phase formed by liquid nitrogen quenching (sample LN-Ny6) melted within the range 193-225°C. The amorphous phase converted into the γ phase below 180°C but into the high-temperature α phase at 180-200°C. Both were stable over 220°C. α- and γ*-crystalline structures were formed by annealing but were not so stable upon heating. Typical double melting peaks were shown on the DSC curve; melt recrystallization happened within the range 100-200°C. The peak at 210°C was mainly due to the melting of the less perfect crystalline structure of the γ phase and a fraction of the α phase; the one at 219°C was due to the high-temperature α- and γ-phase crystals. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

New compounds containing triphenylamine-anthrylenevinylene and tetraphenylethene moieties are synthesized by the Wittig–Horner reaction. The compounds exhibit weak emission in good solvents, but strong fluorescence in aggregates or in the solid state, indicating that they are aggregation-induced emission enhancement compounds. The symmetry of their molecular structure affects their aggregation structures and photoluminescence emission properties in aggregation. These compounds show high thermal stabilities with glass transition temperatures between 168–177 °C and decomposition temperatures between 521–537 °C. The HOMO levels of the compounds are in the region of 4.92–4.94 eV, very close to the work function of indium tin oxide anode (4.8–5.0 eV). One of the compounds exhibits obvious piezofluorochromic behavior. The piezofluorochromic nature is generated through changing the mode of molecular packing under external pressure. [ABSTRACT FROM AUTHOR]

A novel class of compounds containing tetraphenylethylene and dicarbazolyl triphenylethylene moieties combined with different spacers is synthesized. The compounds exhibit high thermal stabilities and aggregation-induced emission properties. The different spacers lead to differences in spatial conformation structures and spatial electron distributions, and markedly affect the thermal and photophysical properties of the compounds. The size of the aggregates formed in water–THF mixtures decreases with increasing water fractions. The time-resolved emission decay behaviors of the synthesized compounds in water–THF mixtures with water fractions from 60% to 99% show three relaxation pathways in their fluorescence decays. [ABSTRACT FROM AUTHOR]

A new class of compounds containing triarylamine and dicarbazolyl triphenylethylene moieties with high thermal stability and aggregation-induced emission enhancement properties was synthesized. The glass transition temperature and 5% weight loss temperature of 3B-TPA are up to 214.3 °C and 516.8 °C, respectively. The compounds exhibited significant photoinduced intramolecular charge-transfer properties. The aggregation considerably affected the π–π* transition and resulted in 6–7 nm red shift of the π–π* absorption wavelength at the peak in UV-vis spectra. The compounds could emit intense blue-green light in aggregated states. [ABSTRACT FROM AUTHOR]

A series of new aggregation-induced emission compounds with strong blue light-emitting properties derived from triphenylethylene were facilely synthesized by a Wittig–Horner reaction of bis(4-bromophenyl)methanone with diethyl 4-bromobenzylphosphonate, followed by a Suzuki reaction with arylboronic acids. Their maximum fluorescence emission wavelengths were 452–462 nm. The glass transition temperatures ranged from 70–145 °C, and the decomposition temperatures were 360–508 °C. The unoptimized device fabricated with benzofuranyl substituted compound as emitter turned on at ∼6 V, and the maximum luminance was ∼1500 cd m−2. [ABSTRACT FROM AUTHOR]

A new cyanoacrylic acid derivative of carbazole-triphenylethylene as a fluorescent probe has been synthesized and characterized. The derivative exhibits not only aggregation-induced effect (AIE) properties, but also interesting fluorescence multi-responses to solvents, water, ethanol and metal ions due to its chemical structure. Responses of the compound solution in DMF to water can be explained in terms of H-bond, multimer and AIE effects. In addition, the derivative was found to be highly sensitive to potassium ions. It is suggested that the compound has potential applications in chemosensors. [ABSTRACT FROM AUTHOR]

The article provides information on a study which investigated the reinforcing and toughening effects of a novel thermo tropic liquid crystalline poly(ester-imide-ketone) (TLCPEIK) with low content on the thermoplastic poly(ether amide) (PEI). The study synthesized the novel TKCPEIK with kink naphthalene structure in the backbone and prepared a series of in situ composites with a low concentration of TLCPEK by direct extrusion.

A new class of aggregation-induced emission (AIE) compounds with strong blue-light-emitting properties and a high thermal stability, derived from triphenylethylene carbazole, has been synthesized. Their glass transition temperatures range from 126–151 °C and the maximum fluorescence emission wavelengths are 451–466 nm. [ABSTRACT FROM AUTHOR]

New star-shaped crystalline molecules have been synthesized through Horner-Emmons reactions using hexyl-substituted thiophene-based carbaldehydes as dendrons and 1,2,4,5-tetra-(diethoxy-phosphorylmethyl)-benzyl-phosphonic acid diethyl ester as the core units; these molecules have been fully characterized. Three thiophene-based star-shaped molecules exhibit good solubility in common organic solvents and good self-film-forming properties. They are intrinsically crystalline as they exhibit well-defined X-ray diffraction patterns from uniform and preferred orientations of molecules. The semiconducting properties of the star-shaped molecules have been evaluated in organic field-effect transistors. Three crystalline conjugated molecules, 4, 8, and 12, exhibit carrier mobilities as high as 6.0 (±0.5) × 10-3, 2.5 (±0.5) × 10-4, and 2.5 (±0.5) × 10-2cm2·V-1·s-1, respectively. The dithienothiophene dendrons in 12induce easy crystallization and small crystallite formation even in as-cast films and can be found to densely cover the surface of a dielectric layer. This helps in attaining good network interconnection of the carrier transport channel, which is responsible for the relatively high carrier mobility in solution-processed organic semiconductors for OFET. [ABSTRACT FROM AUTHOR]

A series of poly(ester imide ketone)s (PEIKs) with varied p‐hydroxybenzoic acid (HBA) molar fraction derived from N,N′‐hexane‐1,6‐diylbis(trimellitimide), 4,4′‐dihydroxybenzophenone, and p‐hydroxybenzoic acid were synthesized by a “step‐feeding” polycondensation method in benzene sulfonyl chloride, dimethylformamide, and pyridine. High field 1H, 13C, and 2D NMR spectroscopy measurements were combined to determine the assignments of hydrogen and carbon atoms in the copolymers. 13C inverse gated decoupling NMR spectra were taken and used as a quantitative method to analyze the chain sequence structures of these copolymers. The liquid crystalline behaviors and thermal properties of the PEIKs were characterized by polarized light microscopy (PLM), wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The NMR studies show that the monomeric unit ratios of the PEIKs are very close to the ratios of the monomers added into the polycondensation process. The analytical results of sequence distribution indicate that the sequence ratios of I‐H, H‐D, and H‐H dias rise with the increase of HBA molar fraction, while that of I‐D decrease. It is worth noting that the sequence ratios of H‐H are always very small among the four sequence ratios although the HBA molar fraction varied from 0 to 50%. It was shown that the copolymers possess a typical nematic thermotropic liquid crystalline character and high thermal stability, which is strongly related with the changes in sequence structure of the molecular chains. This type of liquid crystalline polymers also exhibits excellent fiber‐forming character in the melting state, which would find its potential usages in high performance fiber and fiber modification materials. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3183–3193, 2007 [ABSTRACT FROM AUTHOR]

An ABA block polymer, polyester-b-(aniline trimer)-b-polyester, was synthesized through the reaction of double amino-capped aniline trimer and 6-hexanolide, with stannous octoate as catalyst, via ring-opening polymerization in anhydrous toluene solution. The structure of the block polymer was characterized and verified by ¹H NMR, FT-IR, and UV--vis spectroscopies, CV, and GPC. The molecular weight (5.9x10³ g mol-1) calculated through ¹H NMR was very close to the data collected by GPC (Mn=5.0x10³, Mw=5.8x10³, DMF as solvent). The polymer has good solubility in common organic solvents, such as THF and DMF. Both thermostability and electrostability of the block polymer are enhanced, compared to aniline trimer. Moreover, the polymer's sensitivity to pH value is superior to the stand-alone aniline trimer. The enhancement of both stability and sensitivity may give the block polymer more opportunities to be used as sensor material. [ABSTRACT FROM AUTHOR]

Supramolecular gels with hierarchical order and complexity have been assembled. The gels contain well-defined Ag4L2 luminescent supramolecular cages as cores, which are cross-linked via Ag-P coordination bonding. The resulting gels are highly luminescent and exhibit rich stimuli-responsive behaviors toward mechanical and chemical (nitroexplosive and anions) stimuli. The gels could be transformed to highly luminescent crystal materials upon addition of halogen anions, in which only traces of lumiphor are accommodated in a host crystal matrix. [ABSTRACT FROM AUTHOR]