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1.
Summary A new class of soluble poly(p-phenylenevinylene)-modified conjugated polymers with a simple aromatic unit of 3,4-bis(phenylene)-3-cyclobutene-1,2-dione in the main chain was synthesized by the dehalogenation polycondensation and the Heck reaction. The monomer and the polymers were characterized by FT-IR, 1H-NMR, UV-visible, Elemental Anaylsis, TGA and DSC. The resultant polymers were obtained as yellow powder, formed the brittle film from the DMAc solution. These polymers were soluble in polar aprotic solvents, such as NMP, DMAc, DMF and DMSO. The present polymers show absorption bands in the range of 286∼325nm, corresponding to the π-π* electronic transition of the conjugated polymer backbones. The photoluminescence spectrum of the polymer 1 shows a peak at 471nm while the polymer 2 has the peak at 522nm with DMAc solution, in the blue emission region. Received: 21 January 1999/Revised version: 2 April 1999/Accepted: 5 April 1999  相似文献   

2.
The synthesis of the title complex was achieved via the reaction of a η6-p-dichlorobenzene-η5-cyclopentadienyliron cation with an organic four-arm core to produce the tetrairon complex. This tetrairon-containing core was subsequently polymerized via nucleophilic aromatic substitution with various dinucelophiles such as 4,4′-thiobenzenethiol, bisphenol-A, 4,4′-(1-phenylethylidene)bisphenol, 4,4′-biphenol, bis(4-hydroxyphenyl)methane, producing five different cross-linked cationic organoiron polymers. Another cross-linked polymer was produced via direct polymerization of the four-arm organic core with the η6-p-dichlorobenzene-η5-cyclopentadienyliron cation. Due to the poor solubility of these cross-linked polymers, solid-state 13C CPMAS NMR was performed in order to verify that polymerization was successful. Thermogravimetric analysis (TGA) revealed that following the decoordination of the cyclopentadienyliron moieties, the polymers were thermally stable. Differential scanning calorimetry (DSC) showed that the polymers exhibited glass transition temperatures (T g’s) ranging from 104 to 146°C. This article is dedicated to Professor Ian Manners for his outstanding contribution to the field of metal-containing polymers.  相似文献   

3.
Polyphenylenes consisting of nitrophenylene and didodecyloxy‐p‐phenylene units have been synthesized by Pd‐catalyzed organometallic polycondensation. The polymers showed good solubility and had number–average molecular weights (Mn) of 13,000–37,000. Their spin‐coated films showed fairly high dielectric constants (ε) of 3.75–6.36. The polymers were electrochemically active with electrochemical reduction peaks in the range of ?1.72 to ?1.99 V versus Ag+/Ag in an acetonitrile solution of [NEt4]BF4 (0.10M). The polymer composed of 2,3′‐dinitrobiphenyl and didodecyloxy‐p‐phenylene units showed thermotropic liquid crystalline phase at about 240°C. Cast films of the polymer had a birefringent phase at room temperature, suggesting self‐assembly of the polymer in the solid. XRD studies revealed that the polymers assumed an ordered structure assisted by aggregation of the long alkoxy side chains in the solid. The polymer main chain in the cast film is considered to be aligned parallel with respect to the surface of substrates. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

4.
We synthesized new thiodicarboxylic acids, p-tolylmethylthiomethylsuccinic acid and 1-naphthylmethylthiomethylsuccinic acid, and thiodiols, 2-(p-tolylmethylthiomethyl)-1,4-butanediol and 2-(1-naphthylmethylthiomethyl)-1,4-butanediol, by the addition of dimethyl itaconate with p-tolylmethanethiol or 1-naphthylmethanethiol, followed by hydrolysis or reduction, respectively, of the resultant dimethyl esters. These difunctional monomers were used for the synthesis of new linear polyesters and polyurethanes containing sulfur in the side chain. The polyesters were synthesized by melt polycondensation of the obtained acids with 2,2′-oxydiethanol. We found reduced viscosity, molecular weight (by GPC), and softening temperature for the reaction products. Low molecular weights, low softening temperature, and very good solubility in organic solvents are their characteristics. The polyurethanes were prepared by polyaddition diols with hexamethylene diisocyanate and tolylene diisocyanate in benzene. They were characterized by reduced viscosity and some tensile properties. The polyurethane derived from 2-(p-tolylmethylthiomethyl)-1,4-butanediol and hexamethylene diisocyanate (ηred. 1.17 dL/g) behaves like a high elasticity thermoplastic elastomer. Thermal stability of all polymers was determined by thermogravimetric analysis. The structure of the monomers and polymers were confirmed by elemental analysis and FTIR and 1H-NMR spectroscopy. © 1996 John Wiley & Sons, Inc.  相似文献   

5.
A series of novel polymers (coded as BCT-1 to BCT-6 (BTC is block triphenylamine)) based on N1-(4-aminophenyl)-N1-phenyl benzene-1,4-diamine, pyridine-2,6-dicarboxylic acid, 4,4′-(phenyl azanediyl)dibenzoic acid (PDA), and different diamine compounds were synthesized successfully through a polymer condensation reaction. For comparison, model polymers, BCT–2,6-pyridine dicarboxylic acid (PA) and BCT–PDA, were synthesized as well. The electrochromic properties of the BCTs were determined via an electrochemical workstation and a UV–visible spectrophotometer. Through electrooxidation, the polymer films showed reversible redox processes and steady color changes. In a comparision of the electrochromic characteristics of the BCTs, almost all the novel polymer films showed a better electrochromism stability, a higher electrochromic coloration efficiency (CE), and a more rapid switching time than BCT–PA and BCT–PDA. Among these polymers, BCT-1 exhibited the highest CE of 266.7 cm2/C, and BCT-4 showed the most rapid switching time (color switching time = 3.08 s and bleaching time = 2.01 s). © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47264.  相似文献   

6.
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   

7.
A series of novel aromatic diamines containing kinked m-chloro phenyl moiety was synthesized by the reaction of m-chloro benzaldehyde with 2,6-dimethyl aniline. The tetraimide diacid was synthesized by using the prepared diamine with benzophenone tetracarboxylic acid dianhydride (BPTDA) and p-amino benzoic acid. The polymers were prepared by treating the tetraimide diacid with different aromatic diamines. The structures of the monomers and polymers were identified by 1H-NMR, FTIR,13C-NMR and elemental analysis. The polymers showed excellent thermal stability, solubility and mechanical properties. Their structure–property relationship was studied by comparing these m-chloro polymers with polymers containing rigid Pyridine moiety.  相似文献   

8.
Poly(ester amides) with physical properties similar to those of liquid crystalline polyesters were prepared by acidolysis of poly(ethylene terephthalate) with p-acetamidobenzoic acid and then polycondensation through the acetamido and carboxyl groups. The ester amide polymers had a random sequence distribution, contained some branching, and at low frequencies had relaxation times appreciably longer than those of poly(ethylene terephthalate). Because of the extended chain orientation of the polymer segments that contained p-aminobenzoic acid (PAB) units, the mechanical properties of injection-molded polymers containing 20–30 mole % PAB were anisotropic. The liquid crystalline characteristics and mechanical properties were further increased by incorporating p-hydroxybenzoic acid units into the polymers.  相似文献   

9.
A novel, slow-release polymer containing phosphorous fertilizer was synthesized by the rapid coordination of iron ions with polymers after the microwave radiation polymerization of collagen, 2-acrylamido-2-methyl-1-propanesulfonic acid, and acrylic acid. We obtained an optimized collagen-g-poly(acrylic acid-co-2-acrylamido-2-methyl-1-propane sulfonic acid) collagen-g-p(AA-co-AMPS)–Fe(III) polymer with great equilibrium swelling capacities of 2595 g/g in distilled water and 121 g/g in 0.9 wt % NaCl solution and an excellent sustained fertilizer release of about 30 days. In addition, for the collagen-g-p(AA-co-AMPS)–Fe(III) polymer, the effect of cations on its swelling followed the order K+ > Na+ > Mg2+ > Ca2+. The structure and morphology were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. Moreover, the collagen-g-p(AA-co-AMPS)–Fe(III) polymers emancipated the nutrients in a more controlled manner than collagen-g-p(AA-co-AMPS). The thermal stability, water absorbency, and good slow-release of fertilizer provide the collagen-g-p(AA-co-AMPS)–Fe(III) polymer with great potential as a fertilizer-carrying vehicle and an aquasorb to be applied in agriculture and horticulture. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47178.  相似文献   

10.
To enhance apparent viscosities in brine solutions with high salinities for associative water-soluble polymers, a novel macromonomer (APEO): allyl-capped octylphenoxy poly(ethylene oxide) (degree of polymerization: 14) was synthesized, and a novel tetra-polymer (PAVO) was synthesized by copolymerizing APEO, acrylamide (AM), sodium 2-acrylamido-2-methylpropane sulfonate (NaAMPS), and vinyl biphenyl (VP). The macromonomer and the PAVO polymer were characterized with Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (1H-NMR). The apparent viscosities of PAVO in pure water were very low over all polymer concentrations, and the critical association concentration (C*p) was 0.15 g dL−1. However, in brine solutions above 40 g L−1 NaCl or 10 g L−1 CaCl2, the intermolecular hydrophobic associations of octylphenyl groups and biphenyl groups were enhanced dramatically, the polymer chains were still comparatively extended due to the incorporation of APEO into the polymer, C*p was reduced to 0.10 g dL−1, and the apparent viscosities were significantly higher than in pure water. The PAVO brine solutions exhibited excellent salt-thickening induced by metallic univalent or bivalent cations, heat-thickening effect, shear-thickening behavior, and thixotropy. Moreover, the brine solution also performed good resistance to ageing because of the simultaneous incorporation of bulky side groups. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

11.
The evaluation of frying oils with the p-Anisidine value   总被引:3,自引:2,他引:1  
This study was conducted to examine the relationship of p-anisidine value with headspace volatiles, sensory evaluation, and polymers. Partially hydrogenated soybean frying oil was used to fry shoestring potatoes. The oil was evaluated by p-anisidine value, headspace volatile analysis, sensory evaluation, and polymer analysis. p-Anisidine value was found to be correlated with hexanal (r=0.81), heptanal (r=0.66), t-2-hexenal (r=0.81), t-2-heptenal (r=0.71), t-2-octenal (r=0.92), and t,t-2,4-decadienal (r=0.86) contents. p-Anisidine value was correlated with overall odor intensity (r=0.82) and correlated with fried food odor (r=0.53) and burnt odor (r=0.43). p-Anisidine value and polymers were also correlated (r=0.84).  相似文献   

12.
Tetrahydropyranyl- (THP) and furanyl- (THF) protected polyhydroxystyrene (PHS) polymers have been investigated for their potential use in conjunction with onium salt acid precursors to yield high-sensitivity resist systems. The synthesized polymers have high transmittance at 248 nm (the wavelength used in next-generation excimer laser, KrF exposure tools). At 248 nm the transmittance for a 1-μm thick film is ~ 80% (Abs = 0.097 μm?1). The acid sensitivity of the acetal functionality at room temperature is high, requiring careful handling of all materials to prevent any premature deprotection of the hydroxy group. The highest lithographic sensitivities obtained so far with a system consisting of poly(p-tetrahydropyranyl-oxy-styrene) base resin and 1 mol % of bis (p-tert-butyl phenyl) iodinium triflate (TBIT) was ~ 2 mJ / cm2. High-resolution line and space patterns (0.35 μm) were obtained with a system comprising PHS-p-THP and an acid precursor, using an excimer laser step and repeat exposure at 248 nm.  相似文献   

13.
Summary Synthesis and cyclopolymerization of 5,6;14,15-dibenzo- 1, 2; 18, 19-diepoxy- 4, 7, 10, 13, 16-pentaoxanonadeca- 5,14-diene (3) was carried out. The polymerization of 3 with tin tetrachloride and boron trifluoride etherate gave the polymers with lower molecular weight. Alternatively, triethylaluminium-water-acetylacetone (Vandenberg catalyst) was effective in preparing polymers of high molecular weight which were soluble in p-cresol and p-chlorophenol. The polymers were essentially composed of cyclic constitutional units corresponding to dibenzo-19-crown-6. The cation-binding ability of the polymer showed the highest selectivity for K+.  相似文献   

14.
Summary Polymerization of 1-phenyl-2-(p-phenoxyphenyl)acetylene (p-PhODPA), 1-phenyl-2-(p-methoxyphenyl)acetylene, and 1-phenyl-2-(p-n-butoxyphenyl)acetylene was examined. These monomers polymerized with TaCl5-n-Bu4Sn to give methanol-insoluble polymers in over 60% yields. Poly(p-PhODPA) was a yellow solid completely soluble in toluene, CHCl3, etc., and its weight-average molecular weight was about 1.0x106 or higher. This polymer was thermally very stable (the onset temperature of weight loss in TGA in air was 420 °C). Its oxygen permeability coefficient (P o 2) was 37 barrers (P o 2/P n 2 2.2) and similar to that of natural rubber. In contrast, the other two polymers did not completely dissolve in any organic solvent, and their thermal stability was lower.  相似文献   

15.
The reaction of N-(2,4-dinitrophenyl)pyridinium chloride (salt[Cl]) with sodium salts of anionic dyes, such as acid red 52 (AR52), acid violet 49 (AV49), and coomassie brilliant blue G-250 (CBBG250) involves an anion exchange between the chloride anion of salt(Cl) and sulfonium anion of the dyes, resulting in the generation of novel Zincke salts, namely, salt(AR52), salt(AV49), and salt(CBBG250), respectively. Reactions of salt(AR52), salt(AV49), and salt(CBBG250) with piperazine in the absence of catalysts resulted in the opening of the pyridinium ring to yield ionic polymers comprising units of 5-piperazinium-2,4-dienylideneammonium and the corresponding dye anion, namely polymer(AR52), polymer(AV49), and polymer(SBBG250), respectively. The corresponding model compounds for the polymers were also synthesized by reacting salt(AR52), salt(AV49), and salt(CBBG250) with piperidine. Polymer(AV49) and polymer(SBBG250) were found to be suitable for the detection of nucleosides, DNA, and proteins, realized by monitoring the changes in their UV–vis absorption spectra, arising from the anionic dyes within the polymers. The polymers and the model compounds were electrochemically oxidized in solution.  相似文献   

16.
The synthesis and characterization of calcium‐containing poly(urethane‐ether)s, having ionic links in the main chain, is reported. Calcium salt of p‐hydroxybenzoic acid (HBA‐Ca) was prepared from p‐hydroxybenzoic acid (HBA) and used as the chain extender in the preparation of calcium‐containing poly(urethane‐ether)s. Poly(urethane‐ether)s, having two different compositions, were prepared by varying the mole ratios of poly(tetramethylene glycol), hexamethylene diisocyanate, and HBA‐Ca. The synthesized poly(urethane‐ether)s were characterized by infrared spectroscopy, thermogravimetric analysis, and dynamic mechanical analysis. The presence of calcium in the polymer chain was confirmed by energy‐dispersive X‐ray analysis. The inherent viscosity of metal‐containing polymers decreased with the increase in the metal content of the polymer. The introduction of metal into the polymer lowers the thermal stability of the polymers as indicated by the decreased initial decomposition temperature. The glass transition temperature (Tg) and the storage modulus of the metal‐containing polymers increase with the increase in metal content presumably due to the formation of physical crosslink's in the polymer. From the mechanical studies of the polymer, it was observed that the metal‐containing polymers exhibit high tensile strength and modulus. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.  相似文献   

17.
Frying of frozen foods has become popular because it considerably reduces cooking time. Polymers and cyclic fatty acid monomers (CFAM) formed during frying are potentially toxic and therefore their production should be minimized. Twenty discontinuous fryings of different frozen foods were carried out over ten consecutive days, in sunflower oil (SO) and in high‐oleic acid sunflower oil (HOSO), by adding fresh oil after each frying to bring the volume of the fryer oil back to 3 L. CFAM methyl ester derivates were hydrogenated, isolated, concentrated and quantified by HPLC using a reverse‐phase column, followed by gas chromatography. After 20 fryings, significantly higher contents of polar material, polymers and CFAM (all p <0.001) were found in SO than in HOSO. Bicyclic compound formation was four times higher in SO (p <0.001). The fat from the fried potatoes presented a polymer content very similar to that of their corresponding oils. The 100‐g rations of the SO‐fried potatoes from the 20th frying supply 49 or 15%, respectively, more polymers and CFAM and 1 mg more bicyclic fatty acids than the 100‐g rations of HOSO‐fried potatoes. Because digestion and absorption of polar material, polymers and CFAM occur, the data clearly show the advantageousness and advisability of frying with HOSO rather than SO.  相似文献   

18.
A series of new polyphosphazene polymers were synthesized using three different pendant groups with the goal of probing structure–function relationships between pendant group substitution and polymer swelling/water flux through thin dense films. Formation of polymers with relative degrees of hydrophilicity was probed by varying the stoichiometry of the pendant groups attached to the phosphazene backbone: p‐methoxyphenol, 2‐(2‐methoxyethoxy)ethanol, and o‐allylphenol. The polymers in this study were characterized using NMR, thermal methods, and dilute solution light‐scattering techniques. These techniques revealed that the polymers were amorphous high polymers (Mw = 105–107) with varying ratios of pendant groups as determined by integration of the 1H‐ and 31P‐NMR spectra. Thin dense film membranes were solution‐cast with azo‐bis(cyclohexane)carbonitrile included in the matrix and crosslinked using thermal initiation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 422–431, 2001  相似文献   

19.
Electroactive poly(amic acid), with oligoaniline in the main chain, was synthesized from macro-monomer of oligoaniline and p-phenylenediamine by oxidative coupling polymerization. The polymer characterization included Fourier-transform infrared spectra (FTIR), 1H nuclear magnetic resonance spectra (1H NMR) and gel permeation chromatography (GPC) as a determination of polymer structure, spectral analysis of different oxidation states via UV-visible spectra. Then the obtained poly(amic acid) was heated at 260 °C to induce cyclization, and transformed into polyimide materials. X-ray powder diffraction (XRD) and thermogravimetric analysis (TGA) were used for the characterization of poly(amic acid) and polyimide materials. Moreover, poly(amic acid) and polyimide were tested in 1.0 M H2SO4 aqueous solution by cyclic voltammetry and they showed different electrochemical activity from each other. The prepared poly(amic acid) and polyimide doped with HCl exhibit a large enhancement in the dielectric constant in comparison to that of traditional polymers, ascribed to the improvement in charge delocalization of the polymers by introduction of the conjugated oligoaniline segments.  相似文献   

20.
Three ionic liquid (IL)‐modified porous polymers were synthesized and used for the adsorption of lactic acid. The experimental adsorption kinetics and equilibrium data from the IL‐modified polymers were obtained. The kinetic study revealed a low temperature to be advantageous to the adsorption process. The dependence of the level of lactic acid adsorption on the amount of polymer, initial lactic acid concentration, and pH was examined at equilibrium. The maximum efficiency was obtained using the maximum adsorbent dose. A comparison of lactic acid adsorption at different pH revealed anion exchange to be the main interaction between the lactic acid and polymers, not molecular adsorption. The amounts adsorbed were fitted to the Langmuir, Freundlich, and Temkin equations. The equilibrium data for modified polymers (imidazole modified polymer, methylimidazole modified polymer, and ethylimidazole modified polymer) were best represented by the Langmuir and Freundlich isotherm with R2 values of 0.99. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

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