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1.
A new series of heteroaromatic polyazomethines containing 1,8‐naphthyridine moieties in the polymer backbone were synthesized with a solution polycondensation technique. A new heteroaromatic monomer containing 1,8‐naphthyridine moieties (4‐ethoxy‐2,7‐dicarboxaldehyde‐1,8‐naphthyridine) was synthesized with an analogous synthetic sequence and confirmed by elemental and spectral data. The resulting polymers were characterized by elemental, spectral analyses, solubility and viscometry measurements. All the synthesized polyazomethines had better solubility in polar aportic solvents. The thermal properties of those polymers were evaluated by thermogravimetric analysis, differential thermogravimetry, and differential thermal analysis measurements and correlated to their structural units. All the polymers had nearly similar maximum polymer decomposition temperatures, which were in the range 557–577°C. A very large difference between the glass transitions (92–222°C) was observed. In addition, with gel permeation chromatography, the molecular weight determination of selected examples of those polymers was evaluated. The values of the average molecular weight for polyazomethines 7 b and 7 c were 34,914 and 24,859, respectively. On the other hand, the biological screening of all of the synthesized polyazomethines was performed in variety of bacteria and fungi. Most of the polyazomethines showed a significant influence against Gram‐negative bacteria. The minimum inhibitory concentration of the most active polymers was 0.05 mg/mL. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

2.
Self‐assembly of mesogens in one polymer system reflects the capability for integrating intermolecular interactions and functions of materials. A series of novel supramolecular complexes (SCPs) containing cholesterol derivatives, siloxane backbone and copper phthalocyanine were synthesized. The SCPs were made from sulfonic acid‐containing precursor polymers (SAPs) synthesized by the use of 4‐(allyloxy)benzenesulfonic acid, cholest‐5‐en‐3‐ol‐(3β)‐4‐(allyloxy)benzoate and polymethylhydrosiloxane. Differential scanning calorimetry, polarizing optical microscopy and X‐ray diffraction results confirmed the mesomorphic properties. The SAPs showed smectic phase, but the SCPs showed columnar phase due to more lateral copper phthalocyanine groups in the polymer systems. Moreover, because of rigid side groups and cholesteric polymer, SCPs showed greater d‐spacings between the side mesogenic groups and exhibited very good electrical conductivity. © 2018 Society of Chemical Industry  相似文献   

3.
Copper nanoclusters were synthesized by a chemical reduction of an aqueous copper salt solution by sodium borohydride. A polyaniline nanocomposite containing copper nanoclusters was prepared by polymerizing a monomer aniline hydrochloride solution containing the copper nanoclusters using ammonium persulfate as an oxidizing agent. The synthesized nanocomposite was characterized using various techniques such as UV‐visible spectroscopy, FTIR spectroscopy, X‐ray diffraction (XRD), and transmission electron microscopy (TEM). The presence of copper was confirmed by XRD and the size of the copper clusters was found to be ~53 nm, which is in good agreement with that obtained from the TEM. The synthesized nanocomposite was used to serve as a catalyst in a Wacker oxidation reaction for the conversion of 1‐decene to 2‐decanone in the presence of molecular oxygen. The formation of 2‐decanone was confirmed using GC‐MS. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2412–2417, 2003  相似文献   

4.
A series of conjugated (poly{N‐(2‐ethylhexyl)‐3,6‐carbazole–vinylene‐alt‐[(2,5‐bisphenyl)‐1,3,4‐oxadiazole]}) and nonconjugated (poly{N‐(2‐ethylhexyl)‐3,6‐carbazole–vinylene‐alt‐[(2,5‐bisphenol)‐1,3,4‐oxadiazole]}) and poly{9,9‐dihexyl‐2,7‐fluorene–vinylene‐alt‐[(2,5‐bisphenol)‐1,3,4‐oxadiazole]}) polymers containing oxadiazole and carbazole or fluorene moieties in the polymer backbone were synthesized with a multiple‐step procedure. The properties of the polymers, including the photophysical and electrochemical characteristics, could be fine‐tuned by adjustment of the components or structures in the polymer chains. The polymers were used to examine the hole‐injection/transport behavior as hole‐injection/hole‐transport layers in double‐layer indium tin oxide (ITO)/polymer/aluminum tris(8‐hydroxyquinoline)/LiF/Al devices by the determination of their energy levels. The effects of the polymers in these devices on the charge‐transport behavior were compared with a control device fabricated with poly(ethylenedioxythiophene) (PEDOT)–poly(styrene sulfonate) (PSS). Devices containing the synthesized polymers showed comparable adhesion to the ITO anode and good hole‐injection/transport performance. In addition, they exhibited higher electroluminescence over an identical range of current densities than the control device. This was attributed to the prevention of radiative exciton quenching caused by the PEDOT–PSS interfaces and the improvement of electron/exciton blocking due to the higher electron affinity of the synthesized polymers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

5.
Hexafluoroisopropanol (HFIP) was the most widely used functional group for nerve agents detection. However, to incorporate HFIP group into a polymer backbone, highly toxic hexafluoroacetone gas was needed in a conventional synthetic route. In this article, a new route with low toxicity was proposed to synthesize a strong hydrogen‐bond acidic (HBA) siloxane polymer by using 2‐vinylhexfluoroisopropanol as the raw material in the hydrosilylation reaction. The synthesized fluoroalcoholic linear polysiloxane (LSFA) was characterized by FT‐IR, confirming its molecular structure was much similar to SXFA, a well‐established HBA polymer synthesized by the conventional route. TGA data verified the adduct's thermal stability. The dimethyl methylphosphonate (DMMP) sensing properties of LSFA and SXFA, along with PLF, were compared basing on the surface acoustic wave (SAW) platform. The results demonstrated that the conventional synthetic route was somewhat difficult to handle and control, while the new route was simpler, easier and was an effective and promising alternative. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4516–4520, 2013  相似文献   

6.
The quaternary ammonium monomer 1,1‐diallyl‐4‐methoxycarbonylpiperidinium chloride was synthesized in good yield. On polymerization in water using t‐butylhydroperoxide as initiator, a cationic polyelectrolyte (CPE) with a five‐membered cyclic structure on the polymeric backbone was obtained. On acid hydrolysis, followed by basification, the CPE gave the corresponding polybetaine (PB). The solution properties of these polymers were investigated by potentiometric and viscometric techniques. The PB demonstrated “antipolyelectrolyte” behavior. The basicity constant of the carboxylate functionality in the polyzwitterionic polymers was ‘apparent’ in a 0.1 N NaCl solution and followed the modified Henderson‐Hasselbalch equation. It was found that as the degree of protonation (α) of the whole macromolecule increases, the protonation of the amine nitrogen becomes increasingly more difficult. Unlike other polyzwitterions/polybetaines, the PB was soluble in salt‐free water. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

7.
The objective of this work was to synthesize functional polymers, with boron removal properties, from high molecular weight linear polyols based on N‐methyl‐d ‐glucamine (NMDG) and polyurethane units as crosslinking reagent. For that, (4‐vinylbenzyl)‐N‐methyl‐d ‐glucamine monomer (VbNMDG) was synthesized from vinylbenzyl chloride and NMDG, and subsequently, high molecular weight linear poly(VbNMDG) was obtained by radical free polymerization. Later, polymer dots were obtained from poly(VbNMDG) and urethanization reactions using methylene diphenyl diisocyanate at room temperature. Monomers and polymers were characterized by different techniques (FTIR, DLS, elemental analysis, H1‐NMR). In addition, boron retention properties were studied by diafiltration technique using the azomethine‐H method. It was concluded that synthesis of polymer dots, with high boron retention capacity, can be easily synthesized by procedure described. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43895.  相似文献   

8.
Two linear phosphazene polymers were synthesized with differing amounts of hydrophilic 2‐(2‐methoxyethoxy)ethanol (MEE) and hydrophobic 4‐methoxyphenol (MEOP) substituted on the backbone. These high polymers were cast into membranes and their permeability to water, methanol, ethanol, and 2‐propanol was evaluated as a function of temperature. An additional polymer with a low content of MEE was studied for water permeation and was characterized by trace flux. At higher levels of MEE on the backbone, fluxes of all solvents increased. Solubility also was found to increase with increasing MEE content for all solvents except water. Unexpectedly, water was found to be less soluble in the higher MEE polymer, although higher membrane fluxes were observed. Diffusion coefficients showed the following trend: methanol ? 2‐propanol > ethanol ? water. Finally, the affinity of solvents and polymers was discussed in terms of Hansen solubility parameters. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 939–945, 2005  相似文献   

9.
A series of novel 4‐arylazo‐3‐methylthiophenes was synthesized by the heterocyclization of 2‐arylhydrazono‐2‐acetyl thioacetanilide derivatives with a variety of α‐halogenated reagents, such as chloroacetone, phenacyl bromide, ethyl chloroacetate, and chloroacetonitrile. The structures of the synthesized thiophene derivatives were confirmed by ultraviolet–visible, IR, and 1H‐NMR spectroscopic techniques and elemental analysis. The synthesized dyes were applied to polyester fabrics as disperse dyes, and their fastness properties were evaluated. The dyed polyester fabrics displayed antibacterial efficacy against Gram‐positive (Staphylococcus aureus) and Gram‐negative (Escherichia coli) bacteria. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

10.
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   

11.
A facile and rapid enhanced microwave‐assisted route for one‐pot synthesis has been developed to polymerize indole moiety using two different oxidizing agents for 60 s exposure at 30 ± 1°C. As‐synthesized conducting polyindoles, obtained by varying the synthesis process and oxidant, have been well characterized by various techniques. UV–vis, FT‐IR, and NMR have been used for their structural analysis while gel permeation chromatography, thermogravimetric analysis, and conductivity measurement to evaluate their enhanced properties and to perform a comparative study. Morphological texture of polyindole synthesized via different techniques has studied by scanning electron microscopy analysis. PIn synthesized by KIO3 (microwave synthesis) exhibit interconnecting texture which may be due to high level of supersaturation of solution under the influence of microwave irradiation. Thereafter, electrical property of spin‐coated thin film of polyindole is examined using four probe method and Al metal/semiconducting material Schottky junction. Microwave‐assisted polymer shows better performance for Schottky devices due to difference in charge transport, morphological texture, and distribution of Mn. The PIn synthesized via microwave irradiation with better charge transport across the metal/polymer interfaces shows the potential of this technique for synthesis of such polymers with enhanced electronic properties. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42192.  相似文献   

12.
A high‐performance polymer polyethersulfone (CN‐Azo‐PES), with a flexible ethoxyl linkage between the azobenzene chromophore side chain and the PES backbone, has been designed and successfully synthesized for an application in a WORM type memory device as an active polymer layer. CN‐Azo‐PES has excellent thermal properties with Tg of 151°C and the degradation temperature higher than 373°C, which can contribute to a better performance of the device. The device based on CN‐Azo‐PES exhibits a write‐once read‐many (WORM) type memory performance with an onset voltage as low as ?1.0 V and an ON/OFF current ratio higher than 102 at a reading voltage of 0.4 V. Moreover, the data can be maintained for longer than 4 × 105 s once written and can be read for more than 400 cycles under a reading voltage of 0.4 V. Thus CN‐Azo‐PES can serve as an energy saving memory material in the data storage field of next generation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42644.  相似文献   

13.
A new interesting class of conducting polymer and copolymers based on 4‐teriary butyl‐cyclohexanone in the main chain has been synthesized by solution polycodensation of terephthalaldehyde with 4‐teriary butyl‐cyclohexanone and/or cycloalkanone derivatives. The model compound I was synthesized from the 4‐teriary butyl‐cyclohexanone with benzaldehyde, and its structure was confirmed by elemental and spectral analyses. The resulting polymer and copolymers were characterized by elemental and spectral analyses including Fourier transform infrared spectrometer (FT‐IR) and nuclear magnetic resonance (1H‐NMR), beside solubility and viscometry measurements. The thermal properties of those polymer and copolymers were evaluated by thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) measurements and correlated to their structural units. X‐ray analysis showed that it has some degree of crystallinity in the region 2θ = 5–60°. The UV–visible spectra of some selected polymers were measured in dimethyl sulfoxide (DMSO) solution and showed absorption bands in the range 253–398 nm, due to n–π* and π–π* transition. The morphological properties of selected examples were tested by scanning electron microscope (SEM). Moreover, the electrical conductivities and the doping with iodine were tested. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

14.
The interfacial interaction and orientation of molecules during the polymerization process plays a vital role in the enhancement of the surface properties of conducting polymers. In this perspective, a solid‐phase mechanochemical route is employed to prepare poly(2,5‐dimethoxy aniline) (PDMA) and its salts with superior properties. Various studies performed on the as‐prepared polymer highlights the formation of polymeric particles with excellent physicochemical properties. Elemental analysis showed the presence of dopants anion in the polymeric backbone. Spectroscopic profile of PDMAs revealed the formation of emeraldine form of PDMAs. Moreover, these studies indicate the formation of PDMA‐HCl in a highly doped state. The surface morphological pictures of PDMAs revealed the formation of aggregated microstructured to nanostructured particulates. X‐ray diffraction, cyclic voltammetry were used to evaluate the physicochemical properties of PDMAs. PDMA salts exhibited crystalline behavior and good electrochemical activity. TG/DTA analysis showed that all the PDMAs were thermally stable up to 240°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

15.
We have investigated the optical properties of poly [2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylene vinylene] containing oxadiazole in backbone (MEH‐OPPV) in dilute tetrahydrofuran solution and solid solution films. There is a large dihedral angle between the two adjacent monomer units in MEH‐OPPV, which restrains interchain interactions and destroys the conjugation of the polymer to result in blue shifted absorption and emission spectra. The red shifted photoluminescence (PL) peak is continuously changed in the solid solution films with increasing the concentration of MEH‐OPPV. Comparison with the dilute solution, an obvious shoulder peak at 465 nm is found in the UV–vis absorption and PL excitation (PLE) spectra of the MEH‐OPPV film. The intensity of the PLE shoulder at 465 nm is increased with the concentration of MEH‐OPPV in the solid solution films, which is connected with the aggregation of the MEH‐OPPV chains. The interchain interactions are restrained and the π‐stack aggregates of the polymer chains can not form in the MEH‐OPPV due to the large dihedral angle, and then the interchain species are effectively suppressed in the MEH‐OPPV films. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

16.
A new series of liquid‐crystalline polymers with a polymer backbone of limonene‐co‐methyl methacrylate were synthesized and characterized, and the spacer length was taken to be nine methylene units. The chemical structures of the obtained olefinic compound and polymers were confirmed with elemental analysis and proton nuclear magnetic resonance spectroscopy. The thermal behavior and liquid crystallinity of the polymers were characterized with differential scanning calorimetry and polarized optical microscopy. The polymers exhibited thermotropic liquid‐crystalline behavior and displayed a glass‐transition temperature at 48°C. The appearance of the characteristic schlieren texture confirmed the presence of a nematic phase, which was observed under polarized optical microscopy. These liquid‐crystalline polymers exhibited optical activity. A comparison was also made with polyacrylates and polymethacrylate‐based materials. This revealed that the nature of the polymer backbone had a major effect on the liquid‐crystalline properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4595–4600, 2006  相似文献   

17.
Two new alternating copolymers based on dithienyl benzotriazole segment and phenylene vinyl unit were synthesized by Heck cross coupling method. The polymers exhibited broad absorption bands (from 300 nm to 752 nm for P1 , and from 300 nm to 654 nm for P2 ) in the UV‐visible region with optical bandgap ranging between 1.6 and 1.9 eV and proper electronic energy levels measured by cyclic voltammetry. The photovoltaic properties of the polymers as electron donors with 6.6‐phenyl C61‐butyric acid methyl ester as the electron acceptor in a bulk heterojunction structures were reported. Preliminary results showed moderate power conversion efficiency of 0.36% and 0.4%, respectively, under the illumination of AM 1.5, 100 mW/cm2 with a device structure of ITO/PEDOT : PSS/polymer : PC60BM (1 : 3)/Ca/Al. Furthermore, the side chain effect on properties has also been investigated. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

18.
Three water‐soluble polymers containing linear alkyl monool, 1,2‐diol, and 1,2,3‐triol groups, mostly on the primary amines of polyethylenimine, were synthesized, characterized, and tested for their ability to recover boric acid. The boron‐binding capacities of these polymers and the backbone polyethylenimine were determined by titration, ultrafiltration, and inductively coupled plasma/atomic emission spectroscopy analysis. At low boron concentrations, the 1,2,3‐triol polymer performed better than the 1,2‐diol, whereas at high boron concentrations, the 1,2‐diol outperformed the 1,2,3‐triol. 11B‐NMR spectroscopy and retention studies with various salt concentrations indicated that boron interacted with these two polymers by means of ion pairing with the protonated amines and by borate ester formation. For the monool and the polyethylenimine backbone, the mechanism for boron binding was ion pairing only. These polymers are under consideration for the selective recovery and recycling of enriched boric acid used in the primary coolant loop of pressurized water nuclear reactors. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1590–1604, 2005  相似文献   

19.
Two new poly(p‐phenylenevinylene) (PPV) derivatives containing oxadiazole moiety (OXA‐PPV1 and OXA‐PPV2) were synthesized by the Wittig condensation polymerization reaction. Their thermal and light‐emitting properties were investigated. The single‐ and triple‐layer electroluminescent (EL) devices with configurations of ITO/polymer/Al and ITO/polymer/OXD‐7/Alq3/Al were fabricated. They exhibited blue emission at 470 nm for OXA‐PPV1 and green emission at 560 nm for OXA‐PPV2. The turn‐on voltages of triple‐layer device were 11 V for OXA‐PPV1 and 8 V for OXA‐PPV2. The triple‐layer EL devices showed much better performance than did the single‐layer devices. The spectra indicated energy transfer occurred from segments of side chain to polymer backbone. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 422–428, 2002  相似文献   

20.
A series of linear polystyrene‐based supports has been synthesized using conventional or controlled (reversible addition fragmentation chain transfer or nitroxide‐mediated) free radical polymerizations, in order to modulate their molecular weight characteristics. Polymer post‐modification via esterification of the primary hydroxyl alcohol functionalities, pendant from the polymer backbone, with a mandelic acid derivative introduces efficiently (>85% yield) racemic, enzyme‐cleavable moieties. A study of the interactions of these polymeric substrates with immobilized penicillin G acylase, in mixed organic/aqueous buffer solvent systems, results in a modest enantioselectivity (comparable with that of racemic mandelic acid methyl ester), but reveals that the biocatalytically active moieties on the linear polymers can be cleaved with first‐order rate kinetics, as observed with small molecules in solution; the reaction rates (which can differ by more than one order of magnitude) are influenced both by the synthetic polymer length and by the polymer structure resulting from the method of polymerization used. Copyright © 2012 Society of Chemical Industry  相似文献   

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