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1.
Three novel bithiazole‐containing polymers were synthesized from 2,2′‐diamino‐4, 4′‐bithiazole (DABT) condensed with bismaleimide, bis(methyloxycarbonyl ethyl)tin dichloride (BETD), and 4,4′‐diphenylmethane diisocyanate (DPDI), respectively. A new series of polymeric complexes were prepared from Fe2+ and the three polymers. These polymers and their complexes were characterized through FTIR, 1H‐NMR, and related techniques. The chemical compositions of the complexes were determined by XPS. The presence of the exchange interaction between the unpaired electrons was investigated by ESR spectroscopy. The magnetic behavior of these complexes was measured as a function of the magnetic field strength (0–40 kOe) at 5 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1353–1359, 2001  相似文献   

2.
A novel polymer (poly[2,2'‐(4,4'‐bithiazolylene)][N‐(2‐ethylhexyl)‐3,6‐carbazylene] (PBTCA) was first synthesized from 2,2′‐diamino‐4,4′‐bithiazole and N‐(2‐ethylhexyl)‐3,6‐diformylcarbazole. The structure of the polymer was determined with IR and 1H‐NMR spectroscopy. The PBTCA–Nd3+ complex was prepared via the mixing of neodymium trichloride hexahydrate and PBTCA in dimethyl sulfoxide under a nitrogen atmosphere. The magnetic behaviors of the Nd3+ complex of a poly(Schiff base) were measured as a function of the magnetic field strength (0–50 kOe) at 4 K and as a function of the temperature (4–300 K). The results show that PBTCA–Nd3+ is a ferromagnet when the temperature is below 15 K, and above that, it is a diamagnet. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 443–446, 2006  相似文献   

3.
Two novel bithiazole‐containing polyamides, DClAI and DTTPA, and their complexes were synthesized by condensation and complexation. Novel homogeneous composite films were prepared by in situ blending these complexes with polyvinyl alcohol. These polymeric complexes and composite films were characterized by FTIR. The magnetic properties of the complex and its related composite film were measured using a physical property measurement system. It was found that the properties of films are similar to those of their related polymeric complexes. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1264–1270, 2004  相似文献   

4.
We report the synthesis and linear and third‐order nonlinear optical (NLO) characterization of two novel copolymers containing alternating 3,4‐dialkoxythiophene and 1,4‐bis(1,3,4‐oxadiazolyl)benzene units. The copolymers were synthesized with a precursor polyhydrazide route. Both copolymers exhibited fluorescence around 430 nm under the irradiation of UV light. The NLO measurements were made with the single‐beam Z‐scan technique with Nd:YAG nanosecond laser pulses at 532 nm. The nonlinear refractive index of the investigated copolymers was negative, and the magnitude was as high as 10?10 esu. The samples exhibited strong reverse saturation absorption and very good optical limiting properties at the wavelength used. The concentration dependence of third‐order NLO parameters was studied. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

5.
A polymer containing 1,3,4‐oxadiazole and carbazole units in the main chain and naphthalene moieties as side groups (P‐OCN) was synthesized by the Wittig reaction of [2,5‐bis(3‐tolylene)1′,3′,4‐oxadiazole]‐9‐(α‐naphthyl)‐carbazole polymer (P‐OCN). The optical properties were investigated with ultraviolet–visible absorption and fluorescence emission spectra. The results showed that the luminescence quantum yield of P‐OCN was 0.673 in chloroform, and it emitted blue and blue‐green light with a band gap of 3.49 eV estimated from the onset absorption. Thermogravimetric analysis and differential scanning calorimetry showed that the polymer exhibited good thermal stability up to 354°C with a glass‐transition temperature higher than 110°C. To investigate the donating and accepting capacities of P‐OCN, the fluorescent quenching technique was used to determinate the interactions between the polymer and the electron donor and electron acceptor. The results showed that the light emission could be quenched by both the electron donor (N,N‐dimethylaniline) and electron acceptor (dimethylterephthalate). Furthermore, the interaction between P‐OCN and fullerene was also studied with fluorescent quenching, and the processes followed the Stern–Volmer equation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

6.
The aim of this study was to prepare magnetic beads that could be used for the removal of heavy‐metal ions from synthetic solutions. Magnetic poly(ethylene glycol dimethacrylate–1‐vinyl‐1,2,4‐triazole) [m‐poly(EGDMA–VTAZ)] beads were produced by suspension polymerization in the presence of a magnetite Fe3O4 nanopowder. The specific surface area of the m‐poly(EGDMA–VTAZ) beads was 74.8 m2/g with a diameter range of 150–200 μm, and the swelling ratio was 84%. The average Fe3O4 content of the resulting m‐poly(EGDMA–VTAZ) beads was 14.8%. The maximum binding capacities of the m‐poly(EGDMA–VTAZ) beads from aquous solution were 284.3 mg/g for Hg2+, 193.8 mg/g for Pb2+, 151.5 mg/g for Cu2+, 128.1 mg/g for Cd2+, and 99.4 mg/g for Zn2+. The affinity order on a mass basis was Hg2+ > Pb2+ > Cu2+ > Cd2+> Zn2+. The binding capacities from synthetic waste water were 178.1 mg/g for Hg2+, 132.4 mg/g for Pb2+, 83.5 mg/g for Cu2+, 54.1 mg/g for Cd2+, and 32.4 mg/g for Zn2+. The magnetic beads could be regenerated (up to ca. 97%) by a treatment with 0.1M HNO3. These features make m‐poly(EGDMA–VTAZ) beads potential supports for heavy‐metal removal under a magnetic field. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

7.
Two novel poly(p‐phenylene vinylene) (PPV) derivatives with conjugated thiophene side chains, P1 and P2, were synthesized by Wittig‐Horner reaction. The resulting polymers were characterized by 1H‐NMR, FTIR, GPC, DSC, TGA, UV–Vis absorption spectroscopy and cyclic voltammetry (CV). The polymers exhibited good thermal stability and film‐forming ability. The absorption spectra of P1 and P2 showed broader absorption band from 300 to 580 nm compared with poly[(p‐phenylene vinylene)‐alt‐(2‐methoxy‐5‐octyloxy‐p‐phenylene vinylene)] (P3) without conjugated thiophene side chains. Cyclic voltammograms displayed that the bandgap was reduced effectively by attaching conjugated thiophene side chains. This kind of polymer appears to be interesting candidates for solar‐cell applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

8.
π‐Conjugated poly(3‐nitropyridine‐2,5‐diyl) ( PPy‐3‐NO2 ), poly(3,3′‐dinitro‐2,2′‐bipyridine‐5,5′‐diyl) ( PBpy‐3,3′‐diNO2 ), and a poly(arylene ethynylene) type polymer consisting of a 3,3′‐dinitro‐2,2′‐bipyridine unit ( PAE‐1 ) were synthesized by Cu‐promoted Ullmann coupling reaction and Pd‐catalyzed coupling reaction. PPy‐3‐NO2 and PAE‐1 were soluble in organic solvents such as DMSO, DMF, and chloroform, and gel permeation chromatography analysis showed a number average molecular weight (Mn) of 9,300 and 12,300, respectively. PPy‐3‐NO2 gave intrinsic viscosity, [η], of 0.53 dL g?1 in DMF. PBpy‐3,3′‐diNO2 had somewhat lower solubility. The polymers exhibited a UV–vis peak at about 430 nm. PPy‐NO2 received electrochemical reduction at ?1.5 V versus Ag+/Ag in acetonitrile, and gave an electrochemical redox cycle in a range from 0 to ?1.1 V versus Ag+/Ag in an aqueous solution. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1763–1767, 2006  相似文献   

9.
A polyether, poly[(2,5‐dimethylene‐1,3,4‐oxadiazole)dioxy‐1,4‐phenylene‐1,2‐ethenylene‐1,4‐phenylene‐1,2‐ethenylene‐1,4‐phenylene], based on short alternating conjugated oxadiazole units, has been synthesized, which is a kind of PPV derivative that emits blue light. The resulting polymer is fairly soluble in chloroform. The synthesized polymer shows a UV–visible absorbency maximum wavelength around 310 nm in solution. The photoluminescence maximum wavelength for the resulting polymer appears around 470 nm. The polymer also exhibits good thermal stability up to 300°C under N2 atmosphere. It is also observed that the onset temperature of thermal decomposition is as high as 355°C. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2682–2686, 2002  相似文献   

10.
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   

11.
Dichloromethyl(2,9‐diphenyl‐7,8‐benzophenanthryl)silane ( 1 ) was synthesized by the Diels–Alder reactions of dichloromethylvinylsilane with 2,5‐diphenyl‐3,4‐(o,o′‐biphenylene)cyclopentadienone in a sealed tube. Poly [methylphenylsilylene‐co‐(2,9‐diphenyl‐7,8‐benzophenanthryl)methylsilylene] (PMBSI) was obtained by Wurtz‐type coupling of dichloromethylphenylsilane and 1 and was characterized with Fourier transform infrared, 1H‐NMR, 13C‐NMR, 29Si‐NMR, gel permeation chromatography, and ultraviolet and fluorescence spectroscopy. The conducting properties and thermal properties of the polymer were investigated. Because of the introduction of benzophenanthrene groups into the Si atoms of the polymer, the ultraviolet absorption wavelengths of the PMBSI redshifted significantly in the ultraviolet region, and a strong photoluminescence band could be observed in the visible region. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2445–2450, 2007  相似文献   

12.
N‐2‐thiazolyl(meth)acrylamides were polymerized by a radical route to obtain polymers in good yields. The polymers, with a pendent heterocyclic group, are soluble in common organic solvents, which allow the corresponding metal complexes with higher loads to be prepared easily. FTIR, 1H NMR, and energy‐dispersive X‐Ray spectroscopy (EDX) were applied to characterize these materials. The magnetic behavior of poly(N‐2‐thiazolyl(meth)acrylamide)‐Fe(II) complexes was examined as a function of applied magnetic field at 4 K and as a function of temperature (4 ~ 300 K) at an applied magnetic field of 1 ~ 3 kOe, exhibiting the characteristics of a ferromagnet. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 83–87, 2005  相似文献   

13.
Two novel fully conjugated polymers containing bithiazole rings (PDDBTz and PDABTz) were first synthesized by polycondensation of 2,7-dimethyl-2,4,6-octatriene-1,8-dial with 2,2′-bis(diethylphosphinatyl methyl)-4,4′-bithizole or 2,2′-diamino-4,4′-bithiazole (DABT). The structure of the polymers was determined by IR, 1H NMR and elemental analysis. PDDBTz is soluble in trifluoroacetic acid and DMSO, whereas PDABTz is soluble in common solvent such as THF, DMSO, DMF. Bithiazole rings were introduced to provide bidentate N-donor sites for binding metal ions. Their lanthanide metal complexes were prepared. The magnetic behavior of these polymeric complexes was measured as a function of magnetic field strength (0-60 kOe) at 4 K and as a function of temperature (4-300 K) at magnetic field strength of 30 kOe. The results show that they all exhibit features of soft ferromagnet.  相似文献   

14.
A new ionic polyacetylene was prepared by the activation polymerization of 2‐ethynylpyridine with 2‐(bromomethyl)‐5‐nitrofuran in high yield without any additional initiator or catalyst. This polymerization proceeded well in a homogeneous manner to give a high yield of the polymer (92%). The activated acetylenic triple bond of N‐(5‐nitro‐2‐furanmethylene)‐2‐ethynylpyridinium bromide, formed in the first quaternerization process, was found to be susceptible to linear polymerization. This polymer was completely soluble in such polar organic solvents as dimethylformamide, dimethyl sulfoxide, and N,N‐dimethylacetamide. The inherent viscosities of the resulting polymers were in the range 0.12–0.19 dL/g, and X‐ray diffraction analysis data indicated that this polymer was mostly amorphous. The polymer structure was characterized by various instrumental methods to have a polyacetylene backbone structure with the designed substituent. The photoluminescence peak was observed at 593 nm; this corresponded to a photon energy of 2.09 eV. The polymer exhibited irreversible electrochemical behaviors between the doping and undoping peaks. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

15.
A novel luminescent conjugated polymer, poly[{9‐(α‐naphthyl)‐3,6‐divinylenecarbazolylene}‐altco‐(1,4‐phenylene)] (PNVCP), bearing alternated 9‐(α‐naphthyl)‐carbazole and benzene units, was synthesized via a Wittig–Horner reaction. The solubility, thermal, and optical properties were investigated. It was soluble in common organic solvents, such as tetrahydrofuran and 1,2‐dichlororoethane. Thermogravimetric analysis and differential scanning calorimetry showed that the conjugated polymer exhibited good thermal stability up to 496°C with a glass‐transition temperature higher than 110°C. The photoluminescence properties were studied. The polymer emits blue light and the quantum yield is 93% in solution. The emission spectra exhibited an obvious solvent effect. With the increase of the polarity of the solvents, the fluorescence spectra changed obviously and appeared to be redshifted at room temperature. The redshift was more obvious in aromatic solvents than in aliphatic solvents. When N,N‐dimethylaniline was gradually added into the solution of the conjugated polymer, the emission intensity of the fluorescence decreased. In comparison, the emission intensity of the polymer showed invariability when 1,4‐dicyanobenzene was added into the polymer solution. Moreover, the fluorescence of the polymer could be effectively quenched by fullerene. Overall, the synthesized polymer is a potential candidate material for fabrication of polymeric light‐emitting devices. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 923–927, 2006  相似文献   

16.
The luminescent polymer, F‐DMBN, containing 2,2′‐dimethacrylanido‐1,1′‐binaphthyl (DMBN) and 9,9‐diphenylfluorene, is synthesized by the Heck reaction of halogenated and olefinic monomers. The structures are characterized by MS, 1H‐NMR, and IR, and the photoluminescent properties are investigated by UV/vis absorption and fluorescence spectra. The results show that the polymer emits blue and blue–violet light. The luminescence quantum yield is 0.424 in ethanol and the emission spectra exhibit obvious solvent effects. In addition, the light emitting can be quenched by both electron donor (N,N‐dimethylaniline) and electron acceptor (fullerene), where the processes follow the Stern–Volmer equation. Moreover, the interaction between F‐DMBN and carbon nanotubes is also studied by fluorescent quenching. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 434–438, 2005  相似文献   

17.
Poly[aniline‐coN‐(2‐hydroxyethyl) aniline] was synthesized in an aqueous hydrochloric acid medium with a determined feed ratio by chemical oxidative polymerization. This polymer was used as a functional conducting polymer intermediate because of its side‐group reactivity. To synthesize the alkyl‐substituted copolymer, the initial copolymer was reacted with NaH to obtain the N‐ and O‐anionic copolymer after the reaction with octadecyl bromide to prepare the octadecyl‐substituted polymer. The microstructure of the obtained polymers was characterized by Fourier transform infrared spectroscopy, 1H‐NMR, and X‐ray diffraction. The thermal behavior of the polymers was investigated by thermogravimetric analysis and differential scanning calorimetry. The morphology of obtained copolymers was studied by scanning electron microscopy. The cyclic voltammetry investigation showed the electroactivity of poly [aniline‐coN‐(2‐hydroxyethyl) aniline] and N and O‐alkylated poly[aniline‐coN‐(2‐hydroxyethyl) aniline]. The conductivities of the polymers were 5 × 10?5 S/cm for poly[aniline‐coN‐(2‐hydroxyethyl) aniline] and 5 ×10?7 S/cm for the octadecyl‐substituted copolymer. The conductivity measurements were performed with a four‐point probe method. The solubility of the initial copolymer in common organic solvents such as N‐methyl‐2‐pyrrolidone and dimethylformamide was greater than polyaniline. The alkylated copolymer was mainly soluble in nonpolar solvents such as n‐hexane and cyclohexane. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

18.
Anisotropy was induced in poly‐Schiff bases containing triphenylamine with linearly polarized light at 488 nm. Both writing and relaxation processes were described with a biexponential function. The alignment process involved two response modes: a fast response mode and a slow one. The fast response mode was associated with angular‐dependent trans–cis photoisomerization, whereas the slow one was attributed to the position adjustment of the rigid main chains used to obtain well‐aligned monodomains. The writing rate increased with an increase in the light intensity at a low intensity of the irradiation light. Structural factors such as main‐chain rigidity seemed to play important roles in the remaining stored information. The two polymers had large photoinduced birefringence values (0.01 and 0.0015, respectively). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2274–2279, 2004  相似文献   

19.
N‐2‐Thiazolylmethacrylamide (NTMA) was polymerized by a radical route to obtain the polymer in good yields. The complexes of PolyNTMA with three rare earth ions Nd(III), Pr(III), and Sm(III) were prepared for the first time. FTIR and 1H NMR were applied to characterize these materials. The magnetic behavior of PolyNTMA–metal complexes was examined as a function of applied magnetic field at 4 K and as a function of temperature (4–300 K) at an applied magnetic field of 30 kOe. It was found that Pr(III) complex exhibits an antiferromagnetic property, while Nd(III) and Sm(III) complexes exhibit a special magnetic property different from the typical magnet. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1289–1293, 2006  相似文献   

20.
A blue‐light‐emissive fluorene‐based polyoxadiazole, an n‐type polyfluorene derivative, was synthesized by both one‐step and two‐step methods. Directly polymerized poly[(9,9′‐didodecylfluorene‐2,7‐diyl)‐alt‐(1,3,4‐oxadiazole‐2,5‐diyl)] (PFOx‐DP) exhibited a higher molecular weight and a more efficient photoluminescence quantum yield than poly[(9,9′‐didodecylfluorene‐2,7‐diyl)‐alt‐(1,3,4‐oxadiazole‐2,5‐diyl)] (PFOx) prepared via a polyhydrazide precursor, poly[9,9′‐didodecylfluorene‐2,7‐(2,5‐dihydrazide‐ 1,3,4‐oxadiazole). Both polymers, differently prepared, showed similar photoluminescent properties in 1,2‐dichloroethane. However, in a film state, the influence of the interchain interactions on the photoluminescence of PFOx with the lower molecular weight was larger than on the photoluminescence of PFOx‐DP. The electron‐deficient property of an oxadiazole group in the polymer backbone resulted in low‐lying highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels of ?6.29 and ?3.26eV, respectively, of the polymer suitable for electron‐transport/hole‐blocking layers and emissive layers in multilayer electroluminescence devices. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3112–3118, 2004  相似文献   

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