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With the quick development of flexible memory electronics, multifunctional organic materials have been the necessary for fabricating electronics. In this work, the highly transparent and flexible electrode was successfully prepared by coating the high‐performance silver nanowires (AgNWs) onto the colorless polyimide (PI) substrate. The prepared flexible PI–AgNWs electrodes exhibited a relatively low sheet resistance of 15 Ω/sq with the high transparency of 68% at the wavelength of 400 nm. A novel kind of polyimide TPC6FPI was successfully synthesized and characterized with the excellent thermostability and high glass transition temperature (Tg) above 250°C. Furthermore, a kind of flexible transparent PI–AgNWs/TPC6FPI/Al resistive memory device was prepared and exhibited good SRAM switching behavior with the threshold voltage of around 2.1 V and the ON/OFF current ratio of ˜104, which indicated that multifunctional PI‐based memory device showed the potential to the wearable devices. [ABSTRACT FROM AUTHOR]

Organic room temperature phosphorescence (RTP) materials have drawn wide attention due to their dynamic phosphorescence performance under ambient conditions. However, most of the pure organic RTP materials show low phosphorescence efficiency and short lifetime because of their weak spin–orbit coupling and fast nonradiative decay process. Introducing halogen heavy atoms can effectively improve the efficiency, while the lifetime would be shortened obviously. Thus, there is still a great challenge especially for developing halogen heavy atom free organic RTP materials, with simultaneously enhanced phosphorescence efficiency and lifetime. Herein, it is demonstrated that triphenylphosphine group possesses a strong n‐electron donating character and adopts a rigid tetrahedral configuration, which are in favor of accelerating intersystem crossing process and suppressing the nonradiative decay process, respectively. Benefited from the dual promotion of triphenylphosphine group, the obtained compound named CzPhP shows a decent phosphorescence efficiency of 14.36% and a prolonged lifetime of 340 ms. Another three pentavalent phosphine‐bearing analogs synthesized, i.e., CzPhPO, CzPhPS, and CzPhPSe, also present different conformational aggregations and good RTP performance. The diversity of the RTP performance of these compounds affords a potential application in anticounterfeiting and data encryption. [ABSTRACT FROM AUTHOR]

The BiOCl/graphene composite was synthesized by vapor‐thermal method. The morphologies, structures, chemical states, and optical properties of the samples were systematically characterized. The visible light catalytic activity of the composite was studied by degrading methylene blue (MB). The results show that the sample obtained with 300‐mg BiCl3 and 1‐mg graphene (named Bi300GP1) forms Bi–C bond, has highly exposed (001) facets, forms a tight contact between BiOCl and graphene, and has more electron transfer channels, which effectively promoted the separation and migration of photoexcited carriers. In addition, the introduction of electronic states near the top of the valence band improved the visible light absorption of the sample, and the degradation rate of MB was the highest, which was increased from 76.64% to 98.12%. Meanwhile, it was confirmed by the ESR test that ·O2− played a major role in the photocatalytic degradation process. [ABSTRACT FROM AUTHOR]

A novel composite of N‐doped TiO2‐quantum dots tightly anchored on graphene (denoted as N‐doped TiO2‐QDs@GP) with superior interfacial contact via C–Ti bond was synthesized via the simple one‐pot vapor‐thermal method. The as‐obtained N‐doped TiO2‐QDs@GP includes TiO2 QDs with an average size of 3.28 nm uniformly distributed on the surface of GP. The large specific area and superior interfacial contact via C–Ti bond ensured its potential photocatalytic application. Except for the effective interfacial charge transfer achieved via C–Ti chemical bond between TiO2 QDs and GP, its enhanced visible light absorption and larger oxygen vacancy ratio also make contributions. Electron spin resonance spectra (ESR) were used to study the photocatalytic mechanism, which proved the participation of both superoxide radical (·O2−) and hydroxyl radical (·OH) in the photocatalytic reactions. This work provides a promising one‐pot method for constructing intimately contacted N‐doped TiO2/GP composite with superior interfacial contact via C–Ti bond and excellent photocatalytic activities. [ABSTRACT FROM AUTHOR]

Z-ligustilide is a natural benzoquinone derivative found in many widely used Chinese herbal medicines such as Angelica sinensis (Oliv.) Diels as well as Ligusticum chuanxiong Hort and so on. It has been used as a part of traditional Chinese medicine and is also present in various Chinese medicine preparations. Pharmacokinetic studies have shown that Z-ligustilide has poor oral bioavailability in rats due to severe first-pass metabolic reactions. New evidence suggests that Z-ligustilide has a wide range of pharmacological properties, including anticancer, antiinflammatory, anti-oxidant as well as neuroprotective activities and so on. The literature discussed is derived from readily accessible papers spanning the early 1970s to the end of March 2019. Information were collected from journals, books, and online searches (Google Scholar, PubMed, Science Direct, Science Citation Index Finder, Springer link, and CNKI). This review intends to provide a comprehensive overview of the pharmacokinetics and pharmacology of Z-ligustilide in recent years, with a focus on its biological properties and mechanisms, which is of great significance for Chinese medicine. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of sulfonated poly(arylene ether nitrile) copolymers containing carboxyl groups were synthesized via a nucleophilic aromatic substitution reaction from phenolphthalein, hydroquinone sulfonic acid potassium salt, and 2,6-difluorobenzonitrile in N-methyl pyrrolidone (NMP) with K2CO3 as a catalyst. The synthesized copolymers had good solubility in common polar organic solvents and could be easily processed into membranes from solutions of dimethyl sulfoxide, NMP, N,N′-dimethyl acetylamide, and dimethylformamide. Typical membranes in acid form were gained, and the chemical structures of these membranes were characterized by Fourier transform infrared analysis. The thermal properties, fluorescence properties, water uptake, ion-exchange capacity, and proton conductivities of these copolymers were also investigated. The results indicate that they had high glass-transition temperatures in the range 151-187°C and good thermal stability, with the 10 wt% loss temperatures ranging from 330 to 351°C under nitrogen. The copolymers showed characteristic unimodal ultraviolet-visible (UV-vis) absorption and fluorescence emission, and the UV-vis absorption, fluorescence excitation, and emission peaks of the copolymers were obvious. Moreover, the copolymer membranes showed good water uptake and proton conductivities at room temperature and 55% relative humidity because of the introduction of both sulfonic acid groups and carboxyl groups into the copolymers, whose contents were in ranges 18.45-67.86 and 3.4 × 10−4 to 3.0 × 10−3 s/cm, respectively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40213. [ABSTRACT FROM AUTHOR]

Adding caulis spatholobi residue fiber (CSRF) to reinforce biodegradable poly (propylene carbonate) (PPC) as a reinforcement was investigated. The morphology of CSRF before and after continuous steam explosion, the mechanical and morphological properties of PPC/CSRF bio-composites with different fiber content were investigated using scanning electron microscopy (SEM), mechanical tests and infrared spectroscopy. The tensile strength and modulus, and impact strength of the bio-composites increased as the content of fiber increased in composites, the elongation at break declined. It was found that a small stay-segment in the stress-strain curves and pulled-out fibers on fractured surfaces of the composites. Infrared spectra result showed esterification and formation of hydrogen bonds between the matrix and CSRF. The fractured surface of the composites addressed a promotion of the interfacial interactions. POLYM. COMPOS., 35:208-216, 2014. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Bisphthalonitrile (BAPh)/polyarylene ether nitrile end-capped with hydroxyl groups (PEN-OH) composite laminates reinforced with glass fiber (GF) have been fabricated in this article. The curing behaviors of BAPh/PEN-OH prepolymers have been characterized by differential scanning calorimetry and dynamic rheological analysis. The results indicate that with the introduction of PEN-OH the curing temperature of BAPh has decreased to 229.6-234.8°C and BAPh/PEN-OH prepolymers exhibit large processing windows with relatively low melt viscosity. The BAPh/PEN-OH/GF composite laminates exhibit tensile strength (272.4-456.5 MPa) and modulus (4.9-10.0 GPa), flexural strength (507.1-560.9 MPa), and flexural modulus (24.0-30.4 GPa) with high thermal (stable up to 538.3°C) and thermal stabilities (stable up to 475.5°C). The dielectric properties of BAPh/PEN-OH/GF composite laminates have also been investigated, which had little dependence on the frequency. Meanwhile, scanning electron microscopy results show that the BAPh/PEN-OH/GF composite laminates display excellent interfacial adhesions between the matrix and GFs. Herein, the BAPh/PEN-OH matrix can be a good matrix for high-performance polymeric materials and the advanced BAPh/PEN-OH/GF composite laminates can be used under high temperature environment. POLYM. COMPOS., 34:2160-2168, 2013. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A series of bisphenol A (BPA)-based 2,2-bis-[4-(3,4-dicyanophenoxy)phenyl]propane (BAPh) prepolymers and polymers were prepared using BPA as a novel curing agent. Ultraviolet-visible and Fourier transform infrared spectroscopy spectrum were used to study the polymerization reaction mechanism of the BAPh/BPA polymers. The curing behaviors were studied by differential scanning calorimetry and dynamic rheological analysis, the results indicated that the BAPh/BPA prepolymers exhibit large processing windows (109.5-148.5°C) and low complex viscosity (0.1-1 Pa·s) at moderate temperature, respectively. Additionally, the BAPh/BPA/glass fiber (GF) composite laminates were manufactured and investigated. The flexural strength and modulus of the composite laminates are 548.7-632.8 MPa and 25.7-33.2 GPa, respectively. The thermal stabilities of BAPh/BPA/GF composite laminates were studied by thermogravimetry analysis. The temperatures at 5% weight loss ( T5%) of the composite laminates are 508.5-528.7°C in nitrogen and 508.1-543.2°C in air. In conclusion, the BAPh/BPA systems can be used as superior matrix materials for numerous advanced composite applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

In this study, novel nitrile functionalized graphene (GN-nitrile)/poly(arylene ether nitrile) (PEN) nanocomposites were prepared by an easy solution-casting method and investigated for the effect of surface modification on the dielectric, mechanical and thermal properties. Graphene (GN) was first functionalized by introduction of nitrile groups onto the GN plane, which was confirmed by scanning electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy, thermogravimetric analysis and dispersibility research. Compared with pure GN, the grafted nitrile groups on the GN-nitrile can interact with nitrile groups in PEN and lead to flat but better dispersion and stronger adhesion in/to the PEN matrix. Consequently, GN-nitrile had a more significant enhancement effect on the properties of PEN. The dielectric constant of the PEN/GN-nitrile nanocomposite with 5 wt% GN-nitrile reaches 11.5 at 100 Hz, which is much larger than that of the pure PEN matrix (3.1). Meanwhile, dielectric loss is quite small and stable and the dielectric properties showed little frequency dependence. For 5 wt% GN-nitrile reinforced PEN composites, increases of 17.6% in tensile strength, 26.4% in tensile modulus and 21 °C in Td5% were obtained. All PEN/GN-nitrile nanocomposite films can stand high temperature, up to 480 °C. Hence, novel dielectric PEN/GN-nitrile nanocomposite films with excellent mechanical and thermal properties can be used as dielectric materials under some critical circumstances such as high wear and temperature. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Epoxidized soybean oil (ESO) was blended as a novel plasticizer with polybutylene succinate (PBS) in a twin-screw extruder. The effects of ESO on the mechanical and thermal properties of the PBS/ESO blends were investigated by means of tensile test, differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and scanning electronic microscope. ESO improved elongation at break for PBS, which increased and then decreased with the increase in ESO. Elongation at break reached a maximum of 15 times than that for pure PBS when the ESO loading was 5 wt%. The tensile strength and modulus for the blends were lower than those for pure PBS. Compared with pure PBS, the blends exhibited lower glass transition temperature, crystallization temperature, and melting temperature. The storage modulus and tan δ peaks for the blends were lower compared with that for pure PBS. ESO had very limited compatibility with PBS, and phase separation was observed when more ESO was added. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]