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1.
This research focuses on the syntheses of polyaniline with poly(styrenesulfonic acid) and their electrochemical behavior, including absorbance behavior and electrochemical response time of polyaniline‐poly(styrenesulfonic acid) [PANI–PSSA]. The complexes PANI–PSSA were prepared by electrochemical polymerization of monomer (aniline) with PSSA, using indium‐tin oxide (ITO) as working electrode in 1M HCl solution. Polyaniline (PANI), poly(o‐phenetidine)–poly(styrenesulfonic acid) [POP–PSSA], and poly(2‐ethylaniline)–poly(styrenesulfonic acid) [P2E‐PSSA] also were prepared by electrochemical polymerization and to be the reference samples. The products were characterized by IR, VIS, EPR, water solubility, elemental analysis, conductivity, SEM, and TEM. IR spectral studies shows that the structure of PANI–PSSA complexes is similar to that of polyaniline. EPR and visible spectra indicate the formation of polarons. The morphology of the blend were investigated by SEM and TEM, which indicate the conducting component and electrically conductive property of the polymer complexes. Elemental analysis results show that PANI–PSSA has a nitrogen to sulfur ratio (N/S) of 38%, lower than that for POP–PSSA (52%) and P2E–PSSA (41%). Conductivity of the complexes are around 10?2 S/cm, solubility of PANI–PSSA in water is 3.1 g/L. The UV‐Vis. absorbance spectra of the hybrid organic/inorganic complementary electro‐chromic device (ECD), comprising a polyaniline–poly(styrenesulfonic acid) [PANI–PSSA] complexes and tungsten oxide (WO3) thin film coupled in combination with a polymer electrolyte poly(2‐acrylamido‐2‐methyl‐propane‐sulfonic acid) [PAMPSA]. PANI–PSSA microstructure surface images have been studied by AFM. By applying a potential of ~3.0 V across the two external ITO contacts, we are able to modulate the light absorption also in the UV‐Vis region (200–900 nm) wavelength region. For example, the absorption changes from 1.20 to 0.6 at 720 nm. The complexes PANI–PSSA, POP–PSSA, and P2E–PSSA were prepared by electrochemical polymerization of monomer (aniline, o‐phenetidine, or 2‐ethylaniline) with poly(styrenesulfonic acid), using ITO as working electrode in 1M HCl solution, respectively. UV‐Vis spectra measurements shows the evidences for the dopped polyaniline system to be a highly electrochemical response time, recorded at the temperature 298 K, and the results were further analyzed on the basis of the color‐ discolor model, which is a typical of protontation systems. Under the reaction time (3 s) and monomer (aniline, o‐phenetidine, 2‐ethylaniline) concentration (0.6M) with PSSA (0.15M), the best electrochemical color and discolor time of the PANI–PSSA is slower than POP–PSSA complexes (125/125 ms; thickness, 3.00 μm) and P2E–PSSA complexes. Under the same thickness (10 μm), the best electrochemical color and discolor time of the PANI–PSSA complexes is 1500/750 ms, that is much slower than P2E–PSSA complexes (750/500 ms) and POP–PSSA complexes (500/250 ms). In film growing rate, the PANI–PSSA complexes (0.54 μm/s) are slower than P2E–PSSA complexes (0.79 μm/s) and POP–PSSA complexes (1.00 μm/s), it can be attributed to the substituted polyaniline that presence of electro‐donating (? OC2H5 or ? C2H5) group present in aniline monomer. The EPR spectra of the samples were recorded both at 298 K and 77 K, and were further analyzed on the basis of the polaron–bipolaron model. The narrower line‐width of the substituted polyaniline complexes arises due to polarons; i.e., it is proposed that charge transport take place through both polarons and bipolarons, compared to their salts can be attributed to the lower degree of structural disorder, the oxygen absorption on the polymeric molecular complexes, and due to presence of electro‐donating (? OC2H5 or ? C2H5) group present in aniline monomer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:4023–4044, 2006  相似文献   

2.
Novel phthalocyanine amide polymers (Pc) based on 1,8-naphthalenediamine (Ar) as an aromatic amine and 1,4-diaminobutane (Al) as an aliphatic amine, were synthesized to improve the limited stabilization modes of conventional phthalocyanines. The metal-free phthalocyanines polymers (MF-Pc) were moderately soluble in DMSO only while the metalized forms (Cu&Ni-Pc) were completely insoluble. The structure of the samples was confirmed using Fourier transform infrared (FTIR), ultraviolet–visible spectrometry (UV–vis) and nuclear magnetic resonance (NMR). Additionally, the thermal stability and glass transition temperatures (Tg) were investigated by thermal gravimetric analyzer (TGA) and differential scanning calorimeter (DSC), respectively. The intercalation of the metal-free phthalocyanines, based on the aliphatic amine (MF-PcAl) and aromatic amine (MF-PcAr), into laponite from DMSO solution, was proved by X-ray diffraction (XRD). The basal space of laponite increased from 1.2 to 1.36 nm upon intercalation of MF-PcAl and extended more to 1.91 nm on using MF-PcAr as intercalant while the quaternized forms of MF-Pcs behaved likewise and could not widen the basal space of laponite to more than 1.43 nm which was attributed to the random distribution of the positive charges over the Pc chains which imposed confined arrangement inside the basal space and consequently narrower space than the attained one in the case of nonquaternized phthalocyanines. The plasticized PVC composites based on laponite treated with either MF-PcAl or MF-PcAr exhibited improved resistance to the UV radiation as revealed by the retention of the tensile strength and elongation at rupture after exposure to UV radiation for different time intervals. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

3.
The rheological and colloidal properties of sodium montmorillonite dispersions were investigated in the presence of a special type of cationic polymer [modified poly(ethylene glycol)]. 2‐(Dimethylamino) ethyl methacrylate was polymerized with monomethoxy‐capped oligo(ethylene glycol) via aqueous atom transfer radical polymerization. The tertiary amine residues of the resulting polymer were then quaternized with methyl iodide to obtain a cationic polyelectrolyte. The rheology and ζ‐potential experiments showed that the cationic polymer adsorbed onto the sodium montmorillonite surface strongly. The rheological parameters (plastic viscosity and yield value) were obtained with a rotational low‐shear rheometer. The results indicated a gradual increase in gelation with the addition of the cationic polymer, which reached a maximum at a cationic polymer concentration of 0.4–0.8 g/L. This gel‐like dispersion showed pronounced thixotropy. A further increase in the polymer concentration resulted in a reduction in this gelation. The adsorption of the cationic polymer onto the clay surface reduced the ζ potential to small values, but no isoelectric point was observed. The basal‐spacing measurements showed that the cationic polymer strongly adsorbed onto the sodium montmorillonite instead of entering the montmorillonite layers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 300–306, 2005  相似文献   

4.
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   

5.
The influence of the total comonomer concentration (TCC; 30–42 wt %), emulsifier concentration (EC; 7.3–23 wt %), hydrophilic–lipophilic balance (HLB; 9–9.9), crosslinking agent (N,N′‐methylene bisacrylamide) concentration (CAC; 0–122.8 ppm with respect to TCC), and isopropyl alcohol (chain‐transfer agent) concentration (IPC; 0–1.5 wt % with respect to TCC) on the flocculation performance (FP) of 80/20 wt % acrylamide (AM)/[2‐(acryloyloxy)ethyl]trimethylammonium chloride (ADQUAT) copolymers obtained by semicontinuous inverse microemulsion copolymerization was studied with capillary suction time testing for FP assessment on anaerobic digested sludges. FP increased as TCC decreased, was nearly unaffected by EC, was maximum with an HLB of 9.5, decreased strongly with CAC, and showed a peak value with an IPC of 1 wt %. At a very high TCC, copolymer growth in a highly collapsed state resulted in greatly structured, high weight‐average molar mass flocculants with decreased swelling capacities (SCs), which did not favor bridging flocculation, and in increased shielding of their positive charges, which did not favor charge neutralization flocculation. However, industrially needed latices with both high TCC and good FP could be obtained by the addition of isopropyl alcohol, which, below a concentration of 1 wt %, improved FP by decreasing the weight‐average molar mass and thereby enhancing SC while maintaining long enough chains to be effective for bridging flocculation. On the basis of the results, new star‐shaped ADQUAT/AM copolymers are envisioned as flocculants with superior FP. A synthetic route is proposed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

6.
A series of acrylamide/dimethylaminoethylacrylate methyl chloride copolymers (AM‐co‐DMAEA) was evaluated as flocculants for model Precipitated Calcium Carbonate (PCC) in distilled water. These cationic polyelectrolytes (PEL) differed by their AM/DMAEA ratio, i.e., their charge density, chain architecture (linear and branched), their intrinsic viscosity (IV), and zeta potential of their aqueous solutions. The IV being directly related to the hydrodynamic volume of the PEL and the zeta potential reflecting the effective charges in suspension were selected for practically useful correlations with flocculation performance. The fractal dimension (dF) and the scattering exponent (SE) of the flocs, analyzed by the laser diffraction method, were taken as indication of primary particle and aggregate assembly. For the optimum PEL dosage, SE and dF varied with the IV and zeta potential. It was observable that floc size, floc resistance, and floc reorganization correlate with the PEL characteristics. Copolymers with lower IV, which is here associated with PEL of similar molar mass but lower charge density, yielded larger and less resistant flocs. Copolymers with higher IV originated smaller more compact flocs being more resistant. In high shear situations, where floc breakage should be avoided, as it is the case in papermaking, polymers with high IV yielding large SE are advantageous. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

7.
Novel thermosensitive, cationic polyelectrolyte was obtained by grafting N‐vinylformamide onto hydroxypropylcellulose followed by the hydrolysis of the formamide groups to the amine groups. The effect of the ionic strength on the lower critical solution temperature of the polymers was studied. The interactions of the polymers with sodium dodecyl sulfate (SDS) as a model anionic surfactant were studied. It was found by the measurements of the light scattering and fluorescence spectroscopy that the graft copolymers obtained strongly interact with SDS with the formation of polymer‐surfactant complexes. The values of critical association concentration (cac) of these polymer‐surfactant systems were found to be of the order of 10?5 mol/dm3 at pH = 6.5 and of the order of 10?6 mol/dm3 at pH = 2.5. The polymer was shown to be potentially useful for the purification of water from anionic surfactants. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

8.
This work reports the synthesis of a new water‐soluble conjugated polymer, which interacts specifically with heavy metal ions such as lead and mercury. In order to produce such a material, the fluorescent properties of polythiophene, which constitutes the polymer backbone, were combined with the chelating capacity of meso‐2,3‐dimercaptosuccinic acid, which forms the side‐chain of the conjugated polymer. Thus, the new polymer acts as chemical complexing agent, the fluorescence of which is quenched in the presence of heavy metal ions. A possible explanation of the mechanism of such a variation is also discussed. The system presented is envisaged to be used as a sensor for heavy metal ions that appear as pollutants in the environment .  相似文献   

9.
Rapid flocculation and sedimentation of suspended particles in primary cane sugar juice is achieved using a high molecular weight anionic polymer flocculant. This work reports on efforts to enhance the performance of an anionic flocculant by the addition of cationic polymers. Homopolymers of poly(trimethylammonium ethyl methacrylate chloride) (TMAEMAC) and cationic copolymers of poly(trimethylammonium ethyl acrylate chloride) (TMAEAC) and acrylamide were synthesized and their performance, to enhance the flocculation and sedimentation of cane sugar juice particles, was evaluated by turbidity and settling rate measurements. The charge–patch mechanism best explains the performance of the homopolymers, whereas the action of the copolymers is attributed to the bridging mechanism. The results of this work indicate that the copolymers are more effective than the homopolymers to aid flocculation and sedimentation of the cane sugar juice particles, and that the best‐performing polymers are those that act by the bridging mechanism. Addition of increased amounts of anionic flocculant did not confer an improvement, suggesting that the cationic bridging flocculant targets a different population of particles that is largely responsible for the residual turbidity. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 316–325, 2003  相似文献   

10.
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   

11.
Gelatin‐based graft copolymers of polypropylene (PP), has been synthesized by chemical method using benzoyl peroxide (BPO), as radical initiator. Biodegradation studies of pristine PP and PP‐g‐Gelatin have been carried out by soil burial test in simple soil and soil enriched with nitrogenous content by adding urea. The microbial degradation was substantiated by the direct attack of the microbes on the grafted samples. The rate of degradation by the direct attack was fast in comparison to the degradation in soil burial studies. The biochemical tests performed on the organisms isolated from the soil, identified these organisms as Bacillus circulans, Kurthia gibsonii, and Flavobacterium sp. which helped biodegradation of PP‐g‐Gelatin samples. The degradation of the grafted samples was further confirmed by carrying out the physical characterization of the original samples and the degraded samples by SEM, XRD, and TGA. The XRD and thermal data indicate an increase in the crystallinity of the degraded samples. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

12.
The dynamic rheological properties of an uncharged polymer and charged polyelectrolytes were evaluated in salt‐free water at various concentrations above the entanglement concentration. A poly(acrylic acid) homopolymer was used as the uncharged polymer and was ionized to anionic poly(acrylic acid‐co‐sodium acrylate) at five levels of ionization (0.05, 0.10, 0.15, 0.30, and 0.50). The polymers exhibited a terminal region at a low frequency and a plateau region at a high frequency. The dynamic data for the nonionic parent and all charged polymers could be reduced to a master curve, which indicated a similar distribution of relaxation times for the nonionic and charged polymers. The shear modulus, relaxation time, and zero shear viscosity properties exhibited a concentration and charge density dependence. Higher power‐law exponents for the rheological properties were noted for the nonionic polymer versus the charged derivatives. The number of mechanically active entanglements per number of chains increased with the polymer concentration and charge density. The total number of mechanically active entanglements per number of chains that occurred because of imposing a charge to the nonionic parent did not change with increased concentration, and this indicated a different entanglement mechanism for charged polymers in comparison with their nonionic parent. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

13.
A new anionic conjugated polymer containing a fluorene group in the main chain was designed and synthesized from poly(2,7‐(9,9′‐dihexylfluorene)‐5,5′‐bibenzimidazole) (PFBI). The polymer showed strong blue emission with high quantum efficiency (0.64) at 450 nm in MeOH and the dramatic quenching effect by Methyl Viologen (MV2+). The fluorescence‐quenching effect results from the weak complex formation between an anionic polymer and electron acceptors such as bipyridinium derivatives. The linear Stern–Volmer constant (Ksv) was 3.7×105 M?1 for MV2+. The newly synthesized polymer is expected to show the applicability for biological and chemical sensors. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 900–904, 2004  相似文献   

14.
A new type of polyelectrolyte complexes formed by hyperbranched poly(sulfone‐amine) hydrochlorate and poly(sodium acrylate) has been reported. It has been found that the stoichiometry between polycation and polyanion is 1.16, which means that hyperbranched polyelectrolyte can also form the compact complexes in spite of the ill‐defined structure. Moreover, the effect of various parameters, such as the architecture of poly(sulfone‐amine), molecular weight of polymer, concentration and low molecular salt, on the complexation is also discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2323–2329, 2007  相似文献   

15.
Poly [[2‐methoxy‐5‐(3‐sulfonatopropoxy)‐1, 4‐phenylene]‐1, 2‐ethenediyl] (MPS‐PPV) was an anionic water‐soluble conjugated polymer. A novel single‐component light‐emitting electrochemical cell (LEC) with an indium tin oxide/MPS‐PPV/aluminum sandwich structure has been successfully fabricated. MPS‐PPV serves as both luminescent material and ionic conductor in the active layer. Electroluminescence can be observed under both forward and reverse bias with emission maxima at about 520 nm (green light). In particular, the device has a low turn‐on voltage of about +3V and ?4V, and can sustain long‐term operations without much loss of efficiency at ambient conditions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2930–2936, 2006  相似文献   

16.
Poly(p‐phenylene vinylene) (PPV) nanofibers with disordered, helical, and yarn morphologies were controllably prepared by the electrospinning of a cationic polyelectrolyte precursor in an ethanol solution followed by thermal conversion. Through the tuning of the precursor solution properties and processing variables, the factors affecting the morphology of PPV fibers were studied. The diameter of these PPV nanofibers decreased with a decrease in the precursor concentration, and gradual blueshifts and changes in the relative intensity of the vibronic components in photoluminescence spectra were observed. These nanofibers with excellent fluorescent properties are potentially interesting for many applications such as micro‐ and nano‐optoelectronic devices and systems. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

17.
In this study, we made a new attempt to examine the relationship between the conductivity and the concentration of a polyelectrolyte solution and to prepare multilayer films with cationic lignin and polyanions through layer‐by‐layer self‐assembly. The nitrogen content of trimethyl lignin quaternary amine salt (TLQA) was 3.56%, and the carboxyl content of carboxymethylated poly (vinyl alcohol) (CMPVA) was 0.62 mmol/g. Attenuated total reflectance spectra confirmed that TLQA and CMPVA were fabricated and assembled successfully. The concentration of TLQA had a polynomial correlation with the conductivity [correlation coefficient (R2) = 0.9953], and the concentration of CMPVA was linear with the conductivity (R2 = 0.9819). The electrostatic sequential adsorption process was monitored with a UV–visible spectrophotometer, and the morphology of the (TLQA/CMPVA)n (where n is the number of double membranes) multilayer film was observed by atomic force microscopy and scanning electron microscopy. When the absorbance of the (TLQA/CMPVA)n multilayer film increased linearly, the linear equation was y = 0.0267x + 0.07453 and R2 was 0.9735. When five layers of TLQA and CMPVA were assembled, the surface root mean square roughness of TLQA and CMPVA were 21.07 and 65.28 nm, respectively. When the number of layers increased, the film surface roughness increased. The stability of the multilayer films in aqueous solution was determined by a conductivity meter. The (TLQA/CMPVA)n multilayer film was stable in water. The results of the research demonstrate for the first time that TLQA and CMPVA could be assembled and successfully driven by electrostatic forces. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44416.  相似文献   

18.
Acrylamide/2‐acryloxyethyltrimethylammonium chloride copolymers in inverse microemulsions, with 60% 2‐acryloxyethyltrimethyl ammonium chloride in the monomer feed and a concentration of active matter of 30% (w/w) as flocculants, were obtained by inverse microemulsion copolymerization. Inverse microemulsion formulations of comonomers, interesting from both technical and economical viewpoints, were polymerized by semicontinuous free‐radical copolymerization with sodium disulfite as the initiator. The influence of the formulation composition, hydrophilic‐lipophilic balance (HLB), starting polymerization temperature, and reaction time on the polymerization and final properties of the products as flocculants was studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103:186–197, 2007  相似文献   

19.
Poly(acrylamide‐diallyldimethyl ammonium chloride‐vinyl trimethoxy silane) [P (AM‐DADMAC‐VTMS)] was prepared by inverse free‐radical emulsion polymerization technique. VTMS segment was hydrolyzed and condensed to form three dimensional networks. The effects of different factors, such as hydrophobic monomer feed ratio, cationic monomer feed ratio, pH value, and NaCl concentration, on decolorization efficiency were studied. Moreover, the decolorization mechanism was also explained by analyzing FTIR spectra and UV‐vis spectra. The introduction of VTMS on flocculant enhanced removal efficiency of dye molecules. With the increasing VTMS, adsorption and net roofing‐sweeping action of hydrophobically modified cationic polyacrylamide played the dominant role in the decoloring process of anion dye. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

20.
A new organic coagulant, sago starch (SS)‐graft‐polyacrylamide (PAm), was prepared by the ceric‐ion‐induced redox polymerization of acrylamide (Am) onto SS at room temperature. The effects of the variation of the concentration of Am and the initiator on the percentages of yield and total conversion were investigated. The chemical composition, viscosity, and side‐chain‐average molecular weight of the obtained graft copolymers were determined. The newly obtained coagulant was tested for the treatment of the turbidity of water. The SS‐g‐PAm coagulants were found to achieve water turbidity removal up to 96.6%. The results of this study suggest that SS‐g‐PAm copolymer is a potential coagulant for reducing turbidity during water treatment. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008  相似文献   

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