Synthesis, characterization and fluorescence quenching of conjugated polymer containing triphenylamine group

Poly(triphenylamine-p-phenylenevinylene)s with two different end-groups were obtained through a Wittig polycondensation. The structures of two copolymers were characterized. Ultraviolet and visible spectroscopy (UV-Vis) and photoluminescence (PL) spectra show the end-capped polymer emits intensive green light in both solution and film state. Their applications in the detection of nitro compounds were investigated, and the results show high fluorescence quenching sensitivity of the end-capped polymer towards o-nitrotoluene (o-NT). When the concentration of o-NT was 21.5 × 10⁻³ mol/L, the fluorescence quenching reached 96%. Additionally, after the exposure of polymer film in three different quenchers such as dinitrotoluene (DNT), p-nitrobenzoquinone (p-BQ) and p-nitrotoluene (p-NT) for 600 s, its fluorescence quenching reached 93.6%, 11.5% and 77.9%, respectively. This kind of polymer has great advantages in preparation and may find applications in the detection of nitro explosives. __________ Translated from Journal of Functional Polymers, 2008, 21(1): 11–16 [译自: 功能高分子学报]     

Synthesis and characterization of photoelectronic polymers containing triphenylamine moiety

Several polymers containing triphenylene moieties in main chain were synthesized by Knovenagel or Wittig condensations. The polymers were characterized by ¹H NMR, IR, GPC, TG, UV–vis, FL and CV. Results indicated that PNB, which was prepared from the polycondensation of 4,4′-dialdehyde-4″-n-butyltriphenylamine with 1,4-bis(triphenylphosphonionmethyl)benzene dibromide, is the most thermally stable one and that PNP, which was prepared from the polycondensation of 4,4′-dialdehyde-4″-n-butyltriphenylamine with p-phenylene diacetonitrile, is the most thermally instable one. The fluorescence quantum efficiency of PNB is 94.3%, which is a high value for optoelectronic polymer materials. All the polymers have a similar CV curve with a reversible oxidation peak and two reduction peaks except that PNB has a single reduction peak.     

含噁二唑-三苯胺基的双光子化合物合成及光谱研究

为了开发高强度的有机电致发光材料,合成了一种含空穴传输基团三苯胺、电子传输基团1,3,4-噁二唑,所含的三苯胺和1,3,4-噁二唑基用吡啶基链接,相互之间存在共轭,可形成分子内的偶极,有利于提高载流子传输的性能。用红外光谱、质谱、核磁共振谱和元素分析对合成化合物进行了结构表征,用荧光光谱仪对它们的荧光性能进行了测试,所合成化合物的荧光性能较好,荧光发射波长为446 nm,并且荧光量子产率最高能达到0.42。     

一种新型共轭Schiff碱聚合物的合成与表征

以对苯二甲醛和水合肼为原料,无水乙醇作溶剂合成了一种共轭Schiff碱聚合物,并通过GPC、IR、1 H NMR、紫外-可见吸收光谱和荧光光谱对其分子量和组成结构进行表征。结果表明,该物质为一种分子量较大的共轭Schiff碱聚合物,具有良好的荧光性。     

Synthesis and properties of a new conjugated polymer containing benzodithiophene for polymer solar cells

We have synthesized a new conjugated polymer PBDTDT containing 4,8-dioctyloxybenzo[1,2-b;3,4-b′]di-thiophene and 2,2′-dithiophene via a Stille coupling reaction. The copolymer was characterized by FTIR, NMR, GPC, TGA, DSC, UV–vis absorption, and electrochemical cyclic voltammetry. TGA showed that the copolymer exhibited good thermal stability. The optical, electrochemical, photovoltaic properties, and hole mobility of the copolymer were investigated and discussed. As a result, the polymer solar cell based on PBDTDT with a conventional device configuration of ITO/PEDOT:PSS/PBDTDT:PC₆₁BM/LiF/Al showed a power conversion efficiency of 1.19 %, with a short-circuit current density (J _sc) of 4.72 mA/cm², an open-circuit voltage (V _oc) of 0.6 V and a fill factor of 53.3 % under the AM 1.5G illumination with an intensity of 100 mW/cm² from a solar simulator.     

A novel electrochromic polymer containing triphenylamine derivative and pyrrole

A novel conducting polymer was successfully synthesized via electropolymerization of N¹,N⁴-bis(4-(1H-pyrrol-1-yl)phenyl)-N¹,N⁴-diphenylbenzene-1,4-diamine (DPTPA). This polymer film exhibited six various colors under different potentials. Besides, this polymer film showed high optical contrast (41% at 852 nm, 52% at 617 nm) and fast switching time (1.3 s at 410 nm, 1.4 s at 852 nm and 0.6 s at 617 nm). Cyclic voltammogram and electro-optical study showed that the polymer film has a stable and well-defined reversible redox process as well as electrochromic behavior.     

Synthesis and characterization of new polyimides and polyamide-imides containing azomethine group in the polymer backbone

Summary New aromatic polyimides and polyamide-imides containing azomethine linkages in the polymer backbone have been synthesized by reacting 4,4-bis(isocyanato) benzylidene aniline (AZMI) with pyromellitic dianhydride (PMDA), 3,3, 4,4-benzophenone tetracarboxylic dianhydride (BTDA) and trimellitic anhydride (TMA) by one-step method. The AZMI was synthesized from 4,4-bis(carboxy) benzylidene aniline (AZMA) by a Weinstock modified curtius rearrangement. All the polycondensation reactions were carried out in N-methyl-2-pyrrolidone (NMP) and the polymers obtained were characterized by infrared spectroscopy, solution viscosity, elemental analysis, thermogravimetric analysis, differential scanning calorimetry and X-ray diffraction.NCL Communication No. 4762     

Synthesis and characterization of side chain polymer with helical PLLA segments containing mesogenic end group

Series of mesogenic biphenol derivatives HO6OPPOn (n = 4,6,8) were prepared by asymmetric reaction and purified. Then HOLAxO6OPPOn were prepared with controlled molecular weights by adjusting the feed ratios of HO6OPPOn, SnOct₂ catalyst and LLA by Ring-Opening Polymerization. P-AOLAxO6OPPOn materials were obtained in high yields by the free radical polymerization of polymerizable macromonomers of AOLAxO6OPPOn synthesized by esterization of HOLAxO6OPPOn with acrylic acid in the presence of DCC/DMAP. Their molecular weights were characterized by ¹H NMR and GPC. Differential Scanning Calorimeter method and Polarized Optical Microscopy method were used to study their thermal behaviors. Both AOLAxO6OPPOn and P-AOLAxO6OPPOn materials are found to form LCs with increased T_g, T_m and T_i with longer O-LLA segment length. Polymerization of AOLAxO6OPPOn also resulted in the increase of T_g, T_m and T_i. X-ray diffraction measurements revealed the presence of smectic phase in these materials. The O-LLA segments are in helical structure from CD spectra and this makes the resulting polymer materials good candidate of optical materials for huge optical rotation power.     

Synthesis and characterization of polymer brushes containing metal nanoparticles

Summary Poly(2-hydroxyethyl methacrylate) (PHEMA) brushes were grown from flat silicon wafers with surface-tethered α-bromoester initiator via atom transfer radical polymerization (ATRP) in aqueous media at ambient temperature first. Kinetics studies revealed an approximate linear increase in thickness with reaction time, indicating that the polymerization process owned some “living” character. Then a kind of polymer-metal complexes (PMCs) were obtained after the introduction of Cu²⁺ cations into the PHEMA brushes by the complexing bond between Cu²⁺ cations and the hydroxyl groups in PHEMA brushes. Finally, the Cu²⁺ cations in PMCs were reduced by NaBH₄ and a kind of PHEMA brushes containing metal nanoparticles of Cu⁰ was formed.     

Synthesis and photovoltaic properties of two-dimensional conjugated polythiophene derivatives presenting conjugated triphenylamine/thiophene moieties

In this study we synthesized three two-dimensional (2-D) polythiophene derivatives (PTs), namely PTBPTPA, PTStTPA, and PTCNStTPA, featuring three different conjugated units—biphenyl (BP), stilbene (St), and cyanostilbene (CNSt), respectively—in the polymer backbones and presenting conjugated triphenylamine/thiophene (TPATh) moieties on the side chains. In addition, we also synthesized three conjugated BP-, St-, and CNSt-based main-chain-type conjugated polymers (PTBP, PTSt, and PTCNSt, respectively). Incorporating the St and CNSt moieties into the polymer backbones and appending TPATh units induced high degrees of intramolecular charge transfer within the conjugated frameworks of the polymers, thereby resulting in lower band gap energies and red-shifting of the maximal UV–Vis absorption wavelengths. Moreover, the energy levels of the highest occupied molecular orbitals of the BP-, St-, and CNSt-based main-chain-type and 2-D PTs were lower than that of P3HT, implying that they would be applicable for the preparation of polymer solar cells (PSC) with greater open-circuit voltages. The photovoltaic performances of PSCs fabricated from blends of the 2-D PTs and the fullerene derivative PC₆₁BM were superior to those of PSCs based on the main-chain-type polymer/PC₆₁BM blends.     

Synthesis,characterization, and electro‐optical properties of a soluble conjugated polymer containing an oxadiazole unit in the main chain

A novel copolymer, poly{[2,5‐diphenylene‐1,3,4‐oxadiazole‐vinylene]‐alt‐[2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylenevinylene]}(MEH‐OPPV) containing a high‐electron‐affinity unit of aromatic oxadiazole in the main chain is synthesized through the Wittig condensation reaction. The obtained copolymer is easily soluble in conventional organic solvents. The structure of the copolymer was characterized by Fourier transform infrared, ¹H nuclear magnetic resonance, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and ultraviolet‐visible and photoluminescence spectroscopy. The TGA result indicates that the copolymer has very high thermal stability (stable up to 310°C in nitrogen), while DSC investigation demonstrates that the glass transition temperature (T_g) is 143°C, which might be a merit for the long‐life operation of light‐emitting devices. The absorption spectrum of film sample of the copolymer reveals two peaks at 310 and 370 nm, respectively, and the edge absorption corresponds to a band gap of 2.46 eV. A single‐layer light‐emitting diode device ITO/MEH‐OPPV/Al is successfully fabricated. The device emits visible yellowish‐green light above the bias voltage of 4.0 V under ambient condition. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2618–2623, 2003     

Synthesis,characterization, and properties of interpenetrating polymer networks containing functionalized latex particles

Three-component interpenetrating polymer networks (IPNs) comprising polyurethane (PUR), poly(n-butyl methacrylate) (PBMA), and polystyrene (PS) latex particles were prepared in a modified one-shot synthesis. The hydroxy-functionlized and unmodified polystyrene latex particles were synthesized via a seeded emulsion polymerization. The incorporation of hydroxyethyl methacrylate into the latex particles was confirmed via diffuse reflectance infrared analysis and modulated-temperature differential scanning calorimetry. The IPNs were characterized by dynamic mechanical thermal analysis, tensile testing, hardness measurements, and transmission electron microscopy. The three-component materials exhibited higher values for the Young's modulus and the Shore A hardness and for the dynamic storage modulus in the higher temperature range from 80 to 140°C than did the PUR/PBMA IPN alone. The latex particles with the hydroxyl functionality exhibited a better miscibility with the microheterogeneous PUR/PBMA IPN than did unfunctionalized PS latex particles, and, therefore, resulted in materials with better damping properties in the temperature range between 80 and 140°C. Transmission electron micrographs confirmed the imporved miscibility of the functionalized latex particles. The latex particles were not, however, dispersed on an individual level but formed agglomerates of between 2 and 20 μm. © 1996 John Wiley & Sons, Inc.     

水性羟基丙烯酸树脂的制备及表征

以甲基丙烯酸甲酯、丙烯酸乙酯、甲基丙烯酸、丙烯酸羟丙酯为单体,BPO为引发剂,在氮气保护下,采用溶液聚合法合成了水性羟基丙烯酸树脂,探讨了引发剂用量、反应温度对粒径及转化率的影响,中和度等对其水溶性的影响,并用红外光谱表征了中和前后吸收峰变化,用热重对树脂进行热稳定分析。结果发现,引发剂用量越大,乳液粒径越小,反应温度为120℃时,丙烯酸树脂转化率最高,且时间最短最佳,合成树脂热稳定性良好。     

Synthesis and characterizations of a polyimide containing a triphenylamine derivative as an interlayer in polymer light-emitting diode

Polyimide containing triphenylamine derivative (TPD-PI) was synthesized to prepare a polymer interlayer having insolubility in common nonpolar solvent for light-emitting polymers. N,N′-diphenyl-N,N′-bis(4-aminophenyl)-1,1-biphenyl-4,4′-diamine, as a new triphenylamine-containing diamine monomer, was synthesized by the palladium-catalyzed amination reaction between 4-nitrodiphenylamine and 4,4′-dibromobiphenyl and subsequent reduction of the nitro-intermediate. The TPD-PI was prepared from the synthesized diamine monomer and 4,4′-(hexafluoropropylidene)-diphthalic anhydride by the standard two-step polymerization method, which involved ring-opening polymerization and subsequent cyclodehydration. The structures and properties of the monomer and the resulting polyimide were characterized with ¹H and ¹³C NMR, elemental analysis, gel permeation chromatography, UV-visible spectroscopy, etc. The TPD-PI is readily soluble in aprotic polar solvents such as N-methyl-2-pyrrolidinone and N,N-dimethylformamide and insoluble in nonpolar solvents such as toluene and xylene. The highest occupied molecular orbital (HOMO) level of the TPD-PI was measured to be 5.5 eV by a photoelectron spectrometer in air, and the band gap was calculated as 3.1 eV from the onset of UV-vis spectrum. The polymer light-emitting diode with the thin TPD-PI layer between a hole injection layer and an emitting polymer layer was fabricated to examine the performance of the polyimide as an polymer interlayer. Although the luminous efficiency of the device is lowered by the introduction of the TPD-PI interlayer, the lifetime of the device is improved.     

含1,3,4-噁二唑与苯或吡啶共轭化合物的合成与表征

以间苯二甲酸和2,6-吡啶二甲酸为原料,经酯化、氨解、关环和取代4步反应合成了1,3-二(2-乙酸甲酯基硫醚-1,3,4-噁二唑)-苯和2,6-二(2-乙酸甲酯基硫醚-1,3,4-噁二唑)-吡啶,利用IR、1HNMR及MS对其结构进行表征。在304nm波长光激发下,1,3-二(2-乙酸甲酯基硫醚-1,3,4-噁二唑)-苯(1.0×10-5mol/L的DMF溶液)在357 nm发射荧光;在281 nm波长光激发下,2,6-二(2-乙酸甲酯基硫醚-1,3,4-噁二唑)-吡啶(1.0×10-5mol/L的DMF溶液)在354 nm发射荧光。结果表明,两种目标化合物均具有良好的荧光性能。     

Synthesis,characterization, and gas permeability of aromatic polyimides containing pendant phenoxy group

A diamine containing a pendant phenoxy group, 1-phenoxy-2,4-diaminobenzene, was synthesized and condensed with different aromatic dianhydrides [4,4′-oxydiphthalic dianhydride, 4,4′-(hexafluoroisopropylidene)diphthalic anhydride, 3,3′,4,4′-benzophenone tetracarboxylic dianhydride, 3,3′,4,4′-biphenyltetracorboxylic dianhydride, and pyromellitic dianhydride] by one-step synthesis at a high temperature in m-cresol to obtain polyimides in high yields. Most of the polyimides exhibited good solvent solubility and could be readily dissolved in chloroform, sym-tetrachloroethane, N,N-dimethylformamide, N,N-dimethylacetamide, and nitrobenzene. Their inherent viscosities were in the range of 0.33–1.16 dL/g. Wide-angle X-ray spectra revealed that these polymers were amorphous in nature. All these polyimides were thermally stable, having initial decomposition temperatures above 500°C and glass-transition temperatures in the range of 248–281°C. The gas permeability of 4,4′-oxydiphthalic dianhydride and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride based polyimides was investigated with pure gases: He, H₂, O₂, Ar, N₂, CH₄, and CO₂. A polyimide containing a  C(CF₃)₂ linkage showed a good combination of permeability and selectivity. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

New polymer syntheses. V. Synthesis,characterization, and morphology of new conjugated polymers,copolymers, and terpolymers containing piperidone moiety in main chain

A new interesting category of polyconjugated polymer, poly(3,5‐benzylidene)isopropylpiperidone, was obtained by condensation of isopropylpiperidone with terephthalaldehyde. Copolymerization and terpolymerization with cyclopentanone and/or cyclohexanone were also carried out. The model compound was prepared by the condensation of 2 mol benzaldehyde with isopropylpiperidone; the structure was elucidated by IR, ¹H‐NMR spectra, and elemental analyses. The polymers, copolymers, and terpolymers were characterized by elemental analyses, IR, ¹H‐NMR spectra, UV and visible spectra, viscometry, and X‐ray analysis. The thermal behavior of the synthesized polymers was evaluated by TGA and DSC analyses and correlated with their structures. The morphology of terpolymer IV was examined by a scanning electron microscope. Electrical conductivities in the 10⁻⁹–10⁻¹¹ Ω⁻¹ cm⁻¹ range were observed: doping with iodine showed a small increase. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2369–2377, 1999     

Electrochemical characterization of arylene vinylene oligomers containing triphenylamine and carbazole units

Cyclic voltammetry (CV) has been used to investigate the electrochemical behavior of three arylene vinylene oligomers containing triphenylamine and carbazole units at the ends. The synthesis of oligomers was performed using Wittig reaction conditions, between 4-formyltriphenylamine or 3-formyl-N-hexyl-carbazole and two diphosphonium salts. The cyclic voltammograms, recorded in anodic range of potentials, revealed that the oligomers undergo quasi-reversible or irreversible redox processes. Polymer films were deposited on Pt electrode by CV and CPE (Controlled Potential Electrolysis) methods. The polymer films obtained by electrochemical polymerization methods show no solubility in all organic solvents and present similar FT-IR data with those polymers synthesized by chemical oxidative polymerization. Characterizations of the oligomers were made by ¹H-NMR spectroscopy, UV–Vis and fluorescence spectroscopy. Due to the lack of their solubility, the polymers obtained by electrochemical methods were characterized only by FT-IR spectroscopy.