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1.
High quality poly(indole-5-carboxylic acid) (PICA) films were synthesized electrochemically by direct anodic oxidation of indole-5-carboxylic acid (ICA) in boron trifluoride diethyl etherate (BFEE) containing additional 80% diethyl ether (EE) (by volume). PICA films obtained from this medium showed good electrochemical behavior and good thermal stability with a conductivity of 10−2 S cm−1. The doping level of PICA increased during electrochemical growth processes. Dedoped PICA films were soluble in dimethyl sulfoxide (DMSO). The structure of the polymer were studied by UV-vis spectroscopy, FT-IR spectroscopy and 1H NMR spectroscopy, which indicated that the polymerization occurred at C(2) and C(3) position. Fluorescent spectral studies indicated that PICA was a good blue-light emitter.  相似文献   

2.
High‐quality poly(2‐phenylindole) (PPI) films were synthesized electrochemically by direct anodic oxidation of 2‐phenylindole (PI) in boron trifluoride diethyl etherate (BFEE). The onset oxidation potential of PI in this medium was measured to be only 0.83 V versus a saturated calomel electrode (SCE), which was much lower than that determined in acetonitrile (ACN) containing 0.1 mol L–1 tetrabutylammonium tetrafluoroborate (1.05 V vs. SCE). PPI films obtained from BFEE showed good electrochemical behavior and thermal stability with an electrical conductivity of 10–2 S cm–1. Structural studies showed that the polymerization of PI mainly occurred at the 3,6‐positions. As‐formed PPI films could be partly dissolved in dimethyl sulfoxide. Fluorescence spectral studies indicated that PPI was a blue‐green light emitter. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

3.
High‐quality freestanding and conducting poly[3‐(6‐bromohexyl)thiophene] (PBHT) films with electrical conductivity of 20 S/cm were synthesized electrochemically by direct anodic oxidation of 3‐(6‐bromohexyl)thiophene (BHT) in boron trifluoride diethyl etherate (BFEE). The oxidation potential of BHT in pure BFEE was measured to be only 1.2 V versus saturated calomel electrode, SCE much lower than that determined in acetonitrile (ACN) (1.8 V vs SCE). The polymer films obtained from this media were very shiny and flexible and can be easily cut into various shapes. The structure and morphology of the polymer films were investigated by UV‐vis, infrared, 1H‐NMR spectroscopy, thermal analysis, and scanning electron microscopy (SEM). All these results indicated that the terminal bromide did not have negative effect on the electrochemical polymerization of BHT. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

4.
High quality poly(p‐phenylene) (PPP) film with conductivity of 0.015 S cm?1 was synthesized electrochemically by direct anodic oxidation of p‐terphenyl (PP) oligomers in boron trifluoride diethyl etherate (BFEE) containing 37.5% CH2Cl2 (v/v). The oxidation onset potential of PP in this medium was measured to be only 1.23 V vs. saturated calomel electrode (SCE), which was lower than that determined in CH2Cl2 + 0.1 mol L?1 Bu4NBF4 (1.87 V vs. SCE). As‐formed PPP films showed good electrochemical behavior, good electrochromic property and good thermal stability. The structures and morphology of doped and dedoped PPP were investigated by UV‐vis, FTIR, and Scanning electron micrographs. The infrared spectroscopic measurements for the estimation of chain lengths revealed that PPP was composed of about 10 phenyl rings. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

5.
This article reports experimental work on the effect of N+ ion implantation on third‐order nonlinear optical properties of POT films. Using K2Cr2O7 as oxidizing agent, poly‐ortho‐toluidine (POT) was synthesized in 1 M hydrochloric. The POT films were prepared by spin‐coating method and then implantated by N+ ions (15–30 KeV) at a dose 1.9 × 1016 ions/cm2. The films were characterized by FT‐IR spectroscopy, visible spectroscopy and SEM, their third‐order nonlinear optical susceptibility (χ(3)) were also examined by a degenerate four‐wave mixing (DFWM) system at 532nm. Compared to pristine POT films, the optical band gap obtained from visible spectra decreased from 3.58 to 3.48 eV when the energy was 30 KeV. Also, The χ(3) value of implantated POT films increased from 3.31 × 10−10 esu to 4.04 × 10−9 esu when the implantated energy was 25 KeV. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers  相似文献   

6.
A novel monomer, 2,6‐di(thiophene‐2‐yl)‐3,5bis(4‐(thiophene‐2‐yl)phenyl)dithieno[3,2‐b;2',3'‐d]thiophene ( Th4DTT) has been synthesized and used as an electro‐active material. It has been electropolymerized onto glassy carbon (GC) electrode in sodium dodecyl sulfate (SDS) solution (0.1 M) together with multi‐walled carbon nanotubes (MWCNT). A good capacitive characteristics for P(Th4DTT)/MWCNT composite has been obtained by electrochemical impedance spectroscopy (EIS), which is, to our best knowledge, the first report on capacitor behavior of a dithienothiophene. A synergistic effect has been resolved by Nyquist, Bode‐magnitude—phase and admittance plots. Specific capacitance of the conducting polymer/MWCNT, calculated from cyclic voltammogram (CV) together with area and charge formulas, has been found to be 20.17 F g?1. Long‐term stability of the capacitor has also been tested by CV, and the results indicated that, after 500 cycles, the specific capacitance is 87.37% of the initial capacitance. An equivalent circuit model of Rs(C1(R1(Q(R2W))))(C2R3) has been obtained to fit the experimental and theoretical data. The double layer capacitance (Cdl) value of P(Th4DTT)/MWCNT (4.43 mF cm?2) has been found to be 25 times higher than P(Th4DTT) (Cdl= 0.18 mF cm?2). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40061.  相似文献   

7.
cis‐9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dicarboxylic acid anhydride ( 1 ) was converted to imide acid ( 2 ) by reaction with S‐valine. Compound 2 was converted to the acid chloride ( 3 ) by reaction with thionyl chloride and then treated with 5‐aminoisophthalic acid in dry N,N‐dimethylacetamide to obtain 5‐[(9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dicarboximido)‐3‐methylbutanoylamino]isophthalic acid ( 4 ). Direct step‐growth polymerization of this novel chiral diacid monomer 4 with a series of different diols in a system of tosyl chloride, pyridine, and N,N‐dimethylformamide was carried out. The optically active polyesters (PEs) were obtained with good yield and moderate inherent viscosity ranging from 0.23 to 0.48 dL/g. The resulting polymers were characterized with FTIR, 1H‐NMR, and elemental analysis techniques. The prepared PEs showed good thermal stability up to 320°C as measured by thermogravimetric analysis. Specific rotation experiments demonstrated the induction of optical activity due to successful insertion of S‐valine in the structure of pendant groups. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

8.
O‐Hydroxypropyl‐N‐butyl chitosan (C4‐HPCS) was prepared by microwave irradiation and phase‐transfer catalysis; this consisted of two steps: (1) the synthesis of O‐hydroxypropyl chitosan (HPCS) with chitosan and propylene oxide and (2) the synthesis of C4‐HPCS with HPCS and 1‐butyl bromide. The results of the experiment are as follows: Fourier transform infrared spectroscopy and 1H‐NMR displayed the characteristic peaks of C4‐HPCS, thermogravimetric analysis showed that C4‐HPCS was stable until 240°C, the critical micelle concentration was 0.025 wt %, the surface tension was equal to 65.70 ± 0.09 mN/m, the hydrophile–lipophile balance number value was 13.55, and the emulsifying power, foaming expansion, and foaming volume stability were 73.10, 45, and 94 wt %, respectively. This indicated that C4‐HPCS had superior surface performance and more excellent hydrophilicity. In addition, the microwave irradiation and phase‐transfer catalysis used in the experiment were considered to be more environmentally friendly and time‐saving methods. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41527.  相似文献   

9.
Poly(o‐methyl‐acrylamideyl‐benzoic acid)‐ZnS (P(o‐MAABA)‐ZnS) nanocomposites have been prepared and characterized. The resultant P(o‐MAABA)‐ZnS nanocomposites in solution show two emissions in the purple‐light area (370 nm) and in the blue‐light area (425 nm), which are assigned to the polymer and ZnS nanoparticles, respectively. The coordination between the polymer and Zn2+ and the surface chemical composition has been studied by Infrared spectroscopy and X‐ray photoelectron spectroscopy (XPS). The particle size of ZnS nanoparticles was homogeneous and the average size was 3.8 nm, which were characterized by UV absorption spectrum and X‐ray Diffraction. The P(o‐MAABA)‐ZnS composites displays good film formability and the films also show two emissions in 370 and 425 nm. After doped with Tb3+, there was effective energy transfer from ZnS nanoparticles to Tb3+. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

10.
A novel precursor, 1,2‐bis[6‐(9H‐carbazol‐9‐yl)hexyloxy] benzene (BCHB), was successfully synthesized. Its polycarbazole‐functionalized polycatechol network films, poly{1,2‐bis[6‐(9H‐carbazol‐9‐yl)hexyloxy] benzene} (PBCHB), with good redox activity were formed by the direct anodic oxidation of BCHB in CH2Cl2 and boron trifluoride diethyl etherate binary solvent solution. Ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, 1H‐NMR, and matrix‐assisted laser desorption ionization–time of flight mass spectrometry were used to characterize the polymers. The results indicate that the network polymers could be synthesized electrochemically with different polymerized units by controlled electropolymerization. The PBCHB films prepared at low potential were oligomers with short conjugation lengths and were soluble in common organic solvents, whereas the polymers with long conjugation lengths and hyperbranched network structures obtained at high potential were insoluble. The electrosynthesized polymers exhibited blue emission maxima around 450 nm and were much more redshifted than their monomer. The emissions were also brighter; this indicated the polymers are potential good blue‐light emitters. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

11.
The energetic material, 3‐nitro‐1,5‐bis(4,4′‐dimethyl azide)‐1,2,3‐triazolyl‐3‐azapentane (NDTAP), was firstly synthesized by means of Click Chemistry using 1,5‐diazido‐3‐nitrazapentane as main material. The structure of NDTAP was confirmed by IR, 1H NMR, and 13C NMR spectroscopy; mass spectrometry, and elemental analysis. The crystal structure of NDTAP was determined by X‐ray diffraction. It belongs to monoclinic system, space group C2/c with crystal parameters a=1.7285(8) nm, b=0.6061(3) nm, c=1.6712(8) nm, β=104.846(8)°, V=1.6924(13) nm3, Z=8, μ=0.109 mm−1, F(000)=752, and Dc=1.422 g cm−3. The thermal behavior and non‐isothermal decomposition kinetics of NDTAP were studied with DSC and TG‐DTG methods. The self‐accelerating decomposition temperature and critical temperature of thermal explosion are 195.5 and 208.2 °C, respectively. NDTAP presents good thermal stability and is insensitive.  相似文献   

12.
Two phosphorus‐containing acrylates of 1‐oxo‐2,6,7‐trioxa‐1‐phorsphabicyclo[2,2,2]oct‐4‐yl methyl acrylate and (10‐oxo‐10‐hydro‐9‐oxa‐10λ5‐phosphaphenanthrene‐10‐yl) methyl acrylate were free‐radical‐copolymerized with styrene (St). The r1 reactivity ratio values (related to the novel acrylates) were 0.342 and 0.225, respectively, and the r2 reactivity ratio values (related to St) were 0.432 and 0.503, respectively. The thermal stability of the copolymers was tested by thermogravimetric analysis (TGA) in N2 or air, and the ignitability was tested by measurements of UL‐94 vertical combustion tests and the limiting oxygen index. The results of TGA and combustion tests indicated that the effect of flame retardancy was determined by the nature of the phosphorus‐containing substituent. Compared with the 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide based group, the 1‐oxo‐2,6,7‐trioxa‐1‐phorsphabicyclo[2,2,2]oct‐4‐yl methol based group could enhance the ability of char formation with an antidripping effect. It is concluded that phosphorus‐containing acrylates are potential flame‐retarding monomers for styrenic polymers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

13.
A series of narrow‐band‐gap conjugated copolymers (PFO‐DPT) derived from pyrrole, benzothiadiazole, and 9,9‐dioctylfluorene (DOF) is prepared by the palladium‐catalyzed Suzuki coupling reaction with the molar feed ratio of 4,7‐bis(N‐methylpyrrol‐2‐yl)‐2,1,3‐benzothiadiazole (DPT) around 1, 5, 15, 30, and 50%. The obtained polymers are readily soluble in common organic solvents. The solutions and the thin solid films of the copolymers absorb light from 300 nm to 600 nm with two absorbance peaks at around 380 nm and 505 nm. The PL emission consists mainly of DPT unit emission at around 624–686 nm depending on the DPT content in solid film. The EL emission peaks are red‐shifted from 630 nm for PFO‐DPT1 to 660 nm for PFO‐DPT50. Bulk heterojunction photovoltaic cells fabricated from composite films of copolymer and [6,6]‐phenyl C61 butyric acid methyl ester (PCBM) as electron donor and electron acceptor, respectively, in device configuration: ITO/PEDOT : PSS/PFO‐DPT : PCBM/Ba/Al shows power conversion efficiencies 0.15% with open‐circuit voltage (Voc) of 0.60 V and short‐circuit current density (Jsc) of 0.73 mA/cm2 under AM1.5 solar simulator (100 mW/cm2). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

14.
This paper describes the synthesis, characterization and electro‐optical properties of a 9,10‐phenanthrenequinone (PQ)‐containing alternating conjugated copolymer: poly[(9,10‐phenanthrenequinone‐2,7‐diyl)‐alt‐(9,9‐di‐n‐hexylfluorene‐2,7‐diyl)] (PPQF). The copolymer has good solubility in common organic solvents such as CH2Cl2, CHCl3 and tetrahydrofuran. The polymer structure was determined using 1H NMR, Fourier transform infrared spectroscopy, gel permeation chromatography and elemental analysis. The polymer possesses a low‐energy n → π* electronic state caused by the C?O groups of the PQ repeating units, and exhibits interesting and improved electrochemical reduction activity as compared to poly(9,9‐di‐n‐hexylfluorene‐2,7‐diyl) and molecular PQ. PPQF has no fluorescence in solution but shows interesting transitions from no fluorescence to strong fluorescence after it undergoes electrochemical reduction. The polymer PPQF may find use as a starting material for a range of applications and can also be used to prepare other polymers due to the presence of the PQ repeating units. Copyright © 2007 Society of Chemical Industry  相似文献   

15.
Polythiophene (PTh) films were prepared by the electrochemical polymerization of thiophene in acetonitrile solution with boron fluoride–ethyl ether (BFEE) as the electrolyte. The electropolymerization processes were investigated by cyclic voltammetry. The onset potential of the electropolymerization decreased dramatically with increasing BFEE proportion in the solution. The free‐standing PTh films obtained were characterized by Founier transform infrared spectroscopy, scanning electron microscopy, and X‐ray photoelectron microscopy. The influence of BFEE on the morphology and conductivity of the PTh films was also examined. The binary solvent solution consisted of acetonitrile (10 vol %) and BFEE (90 vol %), which turned out to be the optimal electrosythesis system, in which a current density of 1 mA/cm2 and a monomer concentration of 50 mM were the optimal conditions for electropolymerization. The PTh film obtained under the optimized conditions had a high tensile strength of 60 MPa and a high conductivity of 153 S/cm. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 940–946, 2003  相似文献   

16.
A new blue fluorescent monomer, 9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene, was designed and synthesized in good yield. Its homopolymer poly(9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene) (P(ADN)) and soluble conductive vinyl copolymers poly[(9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene)‐co‐styrene] (P(ADN‐co‐S)) and poly[(9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene)‐co‐(9‐vinylcarbazole)] (P(ADN‐co‐VK)) were synthesized using free radical solution polymerization. All the polymers showed high glass transition mid‐point temperatures (203 to 237 °C) and good thermal stabilities. The photoluminescence emission of the copolymers was similar to that of P(ADN) (with two maxima at 423 and 442 nm). The lifetimes of P(ADN‐co‐S) (6.82 to 7.91 ns) were all slightly less than that of P(ADN) (8.40 ns). The lifetime of P(ADN‐co‐VK) increased from 7.8 to 8.8 ns with an increase in VK content. The fluorescence quantum yields of P(ADN‐co‐S) showed an overall increasing tendency from 0.42 to 0.58. The quantum efficiencies of P(ADN‐co‐VK) decreased from 0.36 to 0.19 with an increase of VK fraction. With increasing S/VK content, the highest occupied molecular orbital of P(ADN‐co‐S)/P(ADN‐co‐VK) ranged from ?5.58 to ?5.73 eV, which was similar to that of P(ADN) (?5.71 eV). The band gaps of P(ADN‐co‐S) and P(ADN‐co‐VK) were about 2.97 eV, which were equal to that of P(ADN), and smaller than that of 2‐methyl‐9,10‐di(1‐naphthalenyl)anthracene (MADN) (3.04 eV) and poly(9‐vinylcarbazole) (3.54 eV). Preliminary electroluminescence results were obtained for a homojunction device with the configuration ITO/MoO3 (20 nm)/P(ADN)/LiF (1 nm)/Al (100 nm), which achieved only 30–50 cd m?2, due to P(ADN) having a low mobility of 4.7 × 10?8 cm2 V?1 s?1 compared to that of its model compound MADN of 6.5 × 10?4 cm2 V?1 s?1. © 2013 Society of Chemical Industry  相似文献   

17.
In situ high‐pressure NMR spectroscopy of the hydrogenation of benzene to give cyclohexane, catalysed by the cluster cation [(η6‐C6H6) (η6‐C6Me6)2Ru33‐O)(μ2‐OH)(μ2‐H)2]+ 2 , supports a mechanism involving a supramolecular host‐guest complex of the substrate molecule in the hydrophobic pocket of the intact cluster molecule.  相似文献   

18.
An asymmetric 3‐oxa‐pentamethylene bridged dinuclear titanocenium complex (CpTiCl2)25‐η5‐C9H6(CH2CH2OCH2CH2)C5H4) ( 1 ) has been prepared by treating two equivalents of CpTiCl3 with the corresponding dilithium salts of the ligand C9H7(CH2CH2OCH2 CH2)C5H5. The complex 1 was characterized by 1H‐, 13C‐NMR, and elemental analysis. Homogenous ethylene polymerization catalyzed using complex 1 has been conducted in the presence of methylaluminoxane (MAO). The influences ofreaction parameters, such as [MAO]/[Cat] molar ratio, catalyst concentration, ethylene pressure, temperature, and time have been studied in detail. The results show that the catalytic activity and the molecular weight (MW) of polyethylene produced by 1 /MAO decrease gradually with increasing the catalyst concentration or polymerization temperature. The most important feature of this catalytic system is the molecular weight distribution (MWD) of polyethylene reaching 12.4, which is higher than using common mononuclear metallocenes, as well as asymmetric dinuclear titanocene complexes like [(CpTiCl2)25‐η5‐C9H6(CH2)nC5H4)] (n = 3, MWD = 7.31; n = 4, MWD = 6.91). The melting point of polyethylene is higher than 135°C, indicating highly linear and highly crystalline polymers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

19.
Color improvement of commercial C9 hydrocarbon resin (c‐C9HR) and prepared C9 hydrocarbon resin (p‐C9HR) has been investigated under various hydrogenation conditions over 2% Pd/γ‐alumina catalysts. The degrees of aromatic rings hydrogenation (DHs) and molecular structure of resin were determined from nuclear magnetic resonance of 1H and 13C (1H‐NMR and 13C‐NMR) and Fourier transform infrared spectroscopy (FTIR) analyses. The starting c‐C9HR presented in yellow color (Gardner color No. 8.4). Under the hydrogenation conditions used (H2 pressure 70 bar, 250°C, and 8 h), the ethylenic proton in c‐C9HR was completely removed, but the aromatic rings content remained unaltered and very little change in resin color was observed (Gardner color No.8.1). On the other hand, the starting p‐C9HR contained only unsaturated aromatic proton with Gardner color No.17.1. Under similar conditions, aromatic rings in p‐C9HR were converted to alicyclic rings, and its color was reduced to Gardner color No.5.7. By varying the DH of aromatics in p‐C9HR, two‐step decolorization was observed in which at lower DH (≤10%) the color decreased sharply from 17.1 to 9.3, while further color reduction to 5.7 was obtained when the DH was increased to 94%. It is suggested that both color body and aromatic rings were the main sources contributing to C9HR color. Nevertheless, color stability of the resin during heat treatment was significantly improved by hydrogenation especially at DH ≥ 50%. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

20.
The electrochemical behaviors of a novel class C60 covalently linked PPV derivatives (i.e., PPV‐1‐C60 and PPV‐2‐C60) in thin solid films as well as in solutions are reported. The first cathodic peak potentials of PPV‐1‐C60 and PPV‐2‐C60 have positive shifts by 30 and 50 mV, respectively, compared to pristine C60 in formal cyclic voltammetry (CV). Simultaneous CV and piezoelectric microgravimetry of the drop‐coated thin solid films of PPV‐1‐C60 and PPV‐2‐C60 in acetonitrile solutions of TBA+ counteractions are strongly influenced by the structure of the polymer‐C60, including the length of the chain macromolecule and the steric hindrance effect. In addition, the atomic force microscopy (AFM) images of PPV‐1‐C60 and PPV‐2‐C60 films deposited on Au/quartz electrode both exhibit even distribution. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2737–2741, 2002  相似文献   

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