JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
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2010
·Vol. 48
·期 13
·2838-2845
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IF 3.971
Li Chen,Tian-Hui Hu,He-Lou Xie,Hai-Liang Zhang
A well-defined structure liquid crystal heptakis [6-deoxy-6-(1-H-1,2,3-triazol-4-yl)(methyl)6-(4-methoxybiphenyl-4′-yloxy) hexanoyl]-β-cyclodextrin (H6B-β-CD) was synthesized from propargyl 6-(4-methoxybiphenyl-4′-yloxy) hexanoate (P6B) and heptakis (6-deoxy-6-azido)-β-cyclodextrin ((N 3 ) 7 -β-CD) by click reaction. The chemical structure of H6B-β-CD was confirmed by 1 H NMR, FTIR, and MALDI-TOF MS. The thermal stability of the compound was investigated by thermogravimetric analysis (TGA). The liquid crystalline behavior was studied by differential scanning calorimetry (DSC), polarizing optical microcopy (POM), and wide-angle X-ray diffraction (WAXD) measurement. These investigations have shown that the supramolecular structure of H6B-β-CD are consisted of a large scale ordered lamellar structure and a small scale ordered structure (SmE) at low temperature region. As the temperature increases, the small scale structure becomes disordered relatively in the first instance, from smectic E to smectic A. Then, the lamellar structure collapses and nematic phase and isotropic phase are observed in sequence. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2838–2845, 2010
研究领域:
材料化学
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超分子化学
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高影响因子
JOURNAL OF CHEMICAL RESEARCH
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2015
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IF 0.633
Xiang Jiang,Guo-Wei Yu,Zu-Guang Li,Shi-Peng Chu,Shen-Peng Wang
2,2-Dichloro-4,4,6,6-bis[spiro(2′,2″-dioxy-1′,1″-biphenylyl)]cyclotriphosphazene was synthesised from the reaction of hexachlorocyclotriphosphazene with biphenyl-2,2′-diol. 2,2-Bis(4-formylphenoxy)-4,4,6,6-bis[spiro(2′,2″-dioxy-1′,1″-biphenylyl)]cyclotriphosphazene was obtained from the reaction of 2,2-dichloro-4,4,6,6-bis[spiro(2′,2″-dioxy-1′,1″-biphenylyl)] cyclotriphosphazene with 4-hydroxybenzaldehyde. 2,2-Bis[4-(4-quinazolinone)phenoxy]-4,4,6,6-bis[spiro(2′,2″-dioxy-1′,1″-biphenylyl)]cyclotriphosphazene was synthesised from the reaction of 2,2-bis(4-formylphenoxy)-4,4,6,6-bis[spiro(2′,2″-dioxy-1′,1″-biphenylyl)]cyclotriphosphazene with anthranilamide in N,N-dimethylformamide. The novel cyclophosphazene derivatives were synthesised under mild conditions from the reaction of 2,2-bis[4-(4-quinazolinone)phenoxy]-4,4,6,6-bis[spiro(2′,2″-dioxy-1′,1″-biphenylyl)]cyclotriphosphazene with 4-chlorobenzenemethanethiol, p-thiocresol, 4-aminothiophenol, and 4-chlorothiophenol in the presence of p-toluenesulfonyl chloride via C-OH bond activation under mild conditions. All products were generally obtained in high yields. Their structures were characterised by HRMS, IR and 1H, 13C spectroscopy.
研究领域:
有机化学
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材料科学
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2024
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IF 5.3
Ran Chen,Junyu Zou,Zihao Mao,Zhongwei An,Pei Chen,Xinbing Chen
Laser display technology can enhance the image quality of liquid–crystal on silicon (LCoS) devices in AR displays. High birefringence (Δ n ), large dielectric anisotropy (Δ ε ), low rotational viscosity ( γ 1 ) and good blue-light stability are inevitable performance requirements for achieving fast response time, low voltage and 2π phase modulation in LCoS devices based on laser display technology. However, people lack attention to how to obtain liquid crystal compounds with above properties. In this work, we propose to utilize one fluorinated terphenyl unit with excellent blue-light stability as the molecular skeleton, and then employ large polar terminal groups to modulate the molecular polarizability and dipole moment , and finally screen to obtain the LCs with high Δ n and large Δ ε . The effects of methyl, fluorinated, chlorinated and cyano terminal groups on the mesomorphic and electro-optical properties of fluorinated terphenyl LCs were systematically studied. Experimental and theoretical results show that the target compounds exhibit wide LC phase intervals, and could enhance the Δ n , Δ ε of the parent LC mixture and reduce its viscoelastic constant, further meaning that they would help to improve the electro-optical properties of LC mixtures for AR displays. Our results would provide experimental data and technical support for the future development of LC mixtures with high blue-light stability for AR displays.
研究领域:
材料科学
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光学
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显示技术
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DOI
高影响因子
LIQUID CRYSTALS
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2023
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IF 2.2
Ran Chen,Wenjing Zhao,Xinbing Chen,Pei Chen,Zhongwei An
A series of liquid crystal (LC) diluters containing a rigid biphenyl core with a lateral fluorine substituent, a 2,2-difluorovinyloxyl terminal group and a flexible n-alkyl chain were designed and synthesised through classical organic synthetic reactions. Their chemical structures were characterised and confirmed by traditional methods. Meanwhile, the effects of alkyl-chain length, terminal group and lateral fluorine substituent on the melting point (Tm), birefringence (Δn), dielectric anisotropy (Δε) and rotational viscosity (γ1) of LC diluters were investigated. Density functional theory (DFT) calculations were employed to obtain the molecular polarisability, dipole moment, frontier orbitals, biphenyl dihedral angle and aspect ratio. Furthermore, their comprehensive properties in low-Δn LC mixture 002 and high-Δn LC mixture P01-F were further evaluated, and it was found that the 2,2-difluorovinyloxyl LC diluter 3FV have a significant advantage in reducing the Tm and γ1 of LC mixtures, and increasing the values of Δn and Δε. The research results provide technical support and theoretical guidance for the molecular design of new LC diluters and the development of fast response liquid crystals.
研究领域:
材料化学
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液晶物理
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DOI
高影响因子
POLYMER INTERNATIONAL
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2020
·Vol. 69
·期 12
·1267-1274
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IF 2.574
Xin Liu,Yanwei Gao,Xuanbo Zhu,Yingshuang Shang,Zengduo Cui,Qixing Yan,Haibo Zhang
Two novel poly(arylene ether sulfone)s with high biphenylene content (BDS-PES and BDS-PDBES) are prepared by nucleophilic substitution polymerization of synthesized 4,4′-bis(4-hydroxyphenyl)diphenyl sulfone (BDS) with 4,4′-sulfonylbis(fluorobenzene) and 4,4-bis[(4-chlorophenyl)sulfonyl], respectively. The prepared polymers show high glass transition temperature and excellent high-temperature mechanical properties. The glass transition temperature of BDS-PDBES with higher biphenylene content is as high as 300 °C, and BDS-PDBES can still maintain its 30% storage modulus at 295 °C. In addition, the two novel polymers also show excellent thermal stability ( T d5 = 526 °C), high elongation at break ( ε ≈ 20%), good tensile strength (73 MPa) and modulus (1.73 GPa) and good thermal conductivity ( λ 300°C = 0.28 W ·m −1 ·K −1 ).
研究领域:
高分子化学
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材料科学
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
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2014
·Vol. 25
·期 9
·920-926
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IF 1.964
Cuihong Zhang,Dongrui Wang,Jin He,Tao Liang,Guo-Hua Hu,Zhi-Min Dang
In this work, self-assembly method was used to improve the dielectric constant of triblock copolymers. A series of ABA triblock copolymers with a defined length of poly(n-butyl acrylate) (PBA, B block) segment and different lengths of liquid crystalline (LC) poly[11-(4-cyano-4′-biphenoxy)undecyl methacrylate] (P11CBMA, A block) segments were synthesized by using the atom transfer radical polymerization method. The well-defined triblock copolymers P11CBMA m - b -PBA n - b -P11CBMA m possess three different B/A ratios ( n = 50, m = 17, 43, 53). Due to the supramolecular cooperative motion effect, the copolymers can form worm-like microstructure ( W LC = 52.8%), cylinder-like nanostructure with P11CBMA phase embedded in PBA matrix ( W LC = 73.9%), and wide stripe structure with LC domains distributed unevenly in a continuous PBA matrix ( W LC = 77.7%) after annealed at 160°C (above T i ) under N 2 for 24 h, respectively. In order to study the influence of microphase separated morphology of triblock copolymer on the dielectric properties, solvent annealing was also used to develop various nanostructures. After thermal or solvent annealing, the dielectric constants of block copolymers increased dramatically while their loss factors remained the same. For different block copolymers, the dielectric constants increased with the increase of the LC block length. For diverse treatments, dielectric permittivities of samples varied widely with different nanostructures. The results show that the dielectric constants of block copolymers could be tuned by the block ratios and the self-assembled microstructures. These findings will inspire researchers using self-assembly method to design and develop novel flexible materials with high dielectric permittivity. Copyright © 2014 John Wiley & Sons, Ltd.
研究领域:
材料科学
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高分子化学
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高影响因子
ORGANIC ELECTRONICS
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2014
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IF 3.676
Chunyu Zhang,Zhanchen Cui,He Wang,Donghang Yan,Yao Li,Zuosen Shi,Aihua Wu,Zhuo Zhao,Shengji Luan
Novel polyurethane containing terphenyl groups were designed and synthesized as gate insulators to induce the crystallization of p-sexiphenyl(p-6P) for organic thin-film transistors (OTFTs). Different sizes and shapes of p-6P grains were measured by atomic force microscopy (AFM), and results showed that the large size of p-6P grain can improve the performance of OTFTs. About 900 nm thick films can be easily fabricated by spin-coating under ambient conditions, followed by curing at UV irradiation for 10 min. OTFTs with this film as gate insulator were found to have good processability, a high charge-carrier mobility of 1.1 cm 2 /V s, a threshold voltage of −25 V, and an on/off current ratio >10 5 . The result indicated that this material is a promising candidate for the exploration of devices using OTFTs.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
Polymer Chemistry
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2023
·Vol. 14
·期 18
·2238-2245
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IF 4.6
Shengqi Ji,Xiaoyan Yuan,Qianjin Guo,Lixia Ren
Self-assembly is a universal method to prepare block copolymers with ordered structures, which is very important in organic magnets to align the magnetic centres to enhance ferromagnetic interaction. The amphiphilic magnetic polymers (PTMTBDI[FeCl4]) with para-terphenyl group in the cations and high spin FeCl4− as single spin carrier are prepared by ring-opening metathesis polymerization (ROMP) and post-modification. Due to the strong π–π stacking interaction between terphenyl groups, magnetic polymers are self-assembled into macromolecular mono-layer structures with hydrophilic FeCl4− on the two sides and the polymer main chain and side group in the middle in aqueous solution. Fe(III) atoms are arranged in lattice fringe with domain spacing of ca. 2.6 Å. Magnetic property studies show that the polymers are changed from paramagnetic to ferromagnetic with hysteresis loops after self-assembly. The ferromagnetic interaction is induced by the close packing and ordered alignment of the Fe(III) atoms. This work unveils a new method to generate ordered structures in angstrom periodicity and thus improve ferromagnetic interaction in organic magnets.
研究领域:
材料科学
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高分子化学
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磁学
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高影响因子
JOURNAL OF POWER SOURCES
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2025
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IF 7.9
Shuanglong Xiao,Yang Zhang,Fan Zhang,Lulu Wang,Shaoji Wang,Shiwen Zhang,Lingzhi Xiong,Jilin Wang
Poly(p-terphenylene quinuclidinium) anion exchange membranes (AEMs) have remarkable chemical stability. However, their application in anion exchange membrane fuel cells (AEMFCs) is limited by the low conductivity resulting from poor ion mobility. In this study, novel poly(p-terphenylene quinuclidinium) polymers grafted with piperidinium suspended at the end of a long flexible alkyl side-chain are designed to prepare AEMs with both high conductivity and stability. The microphase separation morphology can be optimized by modulating the length of the flexible piperidinium side chains. Quaternary ammonium poly(p-terphenylene quinuclidinium) grafted with (6-bromoalkyl)-1-methylpiperidine (QPPTQ-6-Pip) has the most pronounced microphase separation structure, with higher water uptake (110.7 %), and thus the highest conductivity (194.7 mS cm −1 ) at 80 °C. Multi-carbon quinuclidinium's hydrophobicity suppresses swelling (48.4 %, 80 °C), which in combination with the microphase separation results in excellent alkaline stability of the membrane (retained 91.6 % at 80 °C after 1680 h immersion in 1 M NaOH). In addition, the side-chain length modulation enables QPPTQ-6-Pip to have excellent mechanical properties (tensile strength: 52.8 MPa, elongation at break: 21.5 %), thus allowing for application in fuel cells. The single cell test show that the peak power density is able to reach 1.24 W cm −2 , and the performance decays by 13.9 % after 90 h. This study provides an effective strategy to regulate the microstructure and performance of AEMs by grafting side chain engineering, which is of great significance to promote the practical application of high performance AEMs.
研究领域:
材料科学
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高分子化学
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电化学
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能源技术
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DOI
高影响因子
POLYMER
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2024
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IF 4.1
Jie Zhang,Qian Liu,Zijian Li,Guanwen Huang,Hailong Li,Xiuchen Li,Shouhai Zhang,Xigao Jian
The enhancement of thermal resistance and mechanical properties for the soluble poly(aryl ether ketone)s is an important research topic. Based on the idea of introducing twisted N-heterocyclic structure and utilizing the restriction of intramolecular chain rotation by bulky pendant groups, the thermo-resistance, mechanical properties, and surface properties of polymers are modulated while ensuring their solubility. A novel bisphenol-like monomer 1′,4-di(biphenyl)-6,6′-biphthalazin-1,4(2H,3H)-dione (DBBD) and corresponding N-heterocycle copoly (aryl ether ketone)s with pendant biphenyl groups (PDPEKs) are prepared. PDPEKs exhibit good thermal stability in air and nitrogen, and the glass transition temperature ( T g ) is in the range of 288–347 °C. In addition, the storage modulus retention rate of PDPEKs reaches 60.6 % at 250 °C. PDPEKs exhibit good solubility in N-methylpyrrolidone and 1,1,2,2-tetrachloroethane, performing good film-formation properties. The tensile strength of PDPEKs films is between 102 and 121 MPa, the Young's modulus is between 2.01–2.30 GPa, and the water contact angle of PDPEKs is in the range of 79°–84°.
研究领域:
高分子科学
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材料科学
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化学工程
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高影响因子
危险品化学品经营许可证（带存储）