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1.
Poly(o‐amino benzyl amine), poly(m‐amino benzyl amine), and the copolymers with aniline were synthesized in 10?4M HCl by using ammonium persulfate as oxidizing agent. The copolymers were synthesized at various feed mole fractions of comonomer diamine and characterized by elemental analysis, FTIR, 1H‐NMR spectroscopy, and electrical conductivity. The polymerization yield depended on the substituent position in the aromatic ring. Copper ion was incorporated in the polymers and the amount depended on the side groups position in the aromatic ring. The thermal stability increased when copper ions and aniline units were incorporated in the polymers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 31–36, 2004  相似文献   

2.
Poly(2‐aminobenzoic acid) and poly(3‐aminobenzoic acid) were synthesized by chemical polymerization of the respective monomers with aqueous 1M hydrochloric acid and 0.49M sodium hydroxide, using ammonium persulfate as an oxidizing agent. In addition, polymerization in an acid medium was carried out in the presence of metal ions, such as Cu(II), Ni(II), and Co(II). Poly(2‐aminobenzoic acid‐co‐aniline) and poly(3‐aminobenzoic acid‐co‐aniline) were synthesized by chemical copolymerization of aniline with 2‐ and 3‐aminobenzoic acids, respectively, in aqueous 1M hydrochloric acid. The copolymers were synthesized at several mole fractions of aniline in the feed and characterized by UV–visible and FTIR spectroscopy, the thermal stability, and the electrical conductivity. Metal ions, such as Cu(II), Ni(II), and Co(II), were incorporated into homo‐ and copolymers by the batch method. The percentage of metal ions in the polymers was higher in the copolymers than in the homopolymers. The thermal stability of the copolymers increased as the feed mole fraction of aniline decreased and varied with the incorporation of metal ions in the polymers. The electrical conductivity of the homo‐ and copolymers was measured, which ranged between 10?3 and 10?10 S cm?1. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2641–2648, 2003  相似文献   

3.
Poly(m‐aminophenyl acetic acid) was synthesized under different conditions from the respective monomer, using ammonium persulfate as oxidizing agent in both the presence and the absence of CuCl2 in HCl(aq). Moreover, the copolymers between aniline and m‐aminophenyl acetic acid were prepared at several feed mol ratios (f1) of aniline. Copper was introduced by the Batch method in the homo‐ and copolymers of different compositions. The polymers were characterized by FTIR and UV‐vis spectroscopy, elemental analysis, thermal analysis, and electrical conductivity. The thermal stability and the content of copper increased as the content of aniline was increased in the copolymers. Moreover, the copolymers showed a high thermal stability; at 400°C a weight loss < 10% was observed. The electrical conductivity was increased with a higher content of aniline in the copolymers, achieving semiconduction values. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1484–1492, 2003  相似文献   

4.
Homopolymers of aniline, toluidines and their copolymers were synthesized by chemical oxidative polymerization using different ratios of monomers in the feed in H2SO4 medium. The synthesized polymers were characterized by employing Fourier transform infrared, UV‐visible, proton nuclear magnetic resonance, X‐ray diffraction techniques for understanding the details of the structure of the synthesized polymers. Morphological, thermal, and electrical conductivity of the as synthesized polymers were also studied by employing scanning electron microscopy, thermogravimetric analysis, and dc electrical conductivity, respectively. From the SEM images rod shaped nanoparticles were observed in PANI and spherical shaped nanoparticles were observed for copolymers. A three‐step thermal degradation was observed for all the polymers. The electrical conductivities of the copolymers were less compared with PANI, and at higher temperature the conductivities of all the polymers were more or less same. It was observed that yield and intrinsic viscosity of copolymers are not regularly dependant on monomer concentration in the feed. The copolymers show better solubility but lower conductivity than PANI. Properties of homopolymers and copolymers are also pointed out. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

5.
Poly(1,2‐diaminobenzene) (1,2‐DAB) and poly(1,3‐diaminobenzene) (1,3‐DAB) have been synthesized by using ammonium persulfate as oxidizing agent in the presence and in the absence of the following metal ion salts: CuCl2, NiCl2, and CoCl2 with different HCl concentrations. The products showed a different content of the metal ion depending on the HCl concentration. The polymers were characterized by Fourier transform infrared (FTIR), ultraviolet‐visible (UV‐Vis) spectroscopy, thermal analysis, and electrical conductivity. The polymerization yield depended on the presence of metal ions that can react as oxidizing reagents and/or catalysts. The polymerization mechanism depended on the position of the substituent. For poly(1,2‐DAB) a ladder‐type structure was obtained, and for poly(1,3‐DAB) one similar to that of polyaniline. The thermal stability increased as the metal ion content in the polymer matrix increased. The electrical conductivity of the polymer did not depend on the metal ion content in the polymer. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2564–2572, 2002  相似文献   

6.
Poly(2-aminophenol), poly(3-aminophenol), poly(2-aminobenzyl alcohol), and poly(3-aminobenzyl alcohol) were synthesized by using ammonium persulphate as oxidizing reagent in HCl and HCl/CH3CN mediums in the presence and absence of Cu(II), Ni(II), and Co(II) ions. The polymers were characterized by Fourier transform infrared spectroscopy, ultraviolet-vis spectroscopy, thermal analysis, and electrical conductivity measurements. The substituent in 2- and 3-positions decreases the yield regarding aniline. Poly(2-,3-aminobenzyl alcohol) are obtained in an intermediate redox state and polymerized as aniline. On the contrary, poly(aminophenols) are obtained as overoxidated structures. The presence of metal ion produces an important increase of the polymerization yield. The metal cations would act as oxidizing agents. The incorporation of these metal ions depends on the reaction medium. The metal ion increases the thermal stability. Poly(2-aminobenzyl alcohol)-copper ions also increases the electrical conductivity. The electrical conductivity is higher by acid doping than by the incorporation of metal ions. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 330–337, 2001  相似文献   

7.
The copolymerization technique is an easy way to achieve better properties in a polymer. Copolymers of benzidine with aniline and its substituted derivatives in different comonomer proportions were synthesised using chemical and electrochemical methods. The characterization of the copolymers included elemental, IR, FTIR, XPS, TGA, thermal aging, and electrical conductivity studies. Specific conductivities of copolymers were obtained at different temperatures. Activation energies were calculated from the change in conductivity with temperature. The effect of steric influence on the electrical conductivities of copolymers was observed. Conductivity is also found to be highly dependent on factors like moisture and % doping. Thermal analysis shows a good thermal stability of the copolymers. The thermal aging process also supports the results obtained from TGA. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 2421–2432, 1997  相似文献   

8.
Summary Poly(2-aminophenol) and poly(3-aminophenol) were synthesized from the respective monomers by using CuCl2 × 2H2O and ammonium persulfate as oxidizing agents in HCl(aq). The materials were characterized by FT-IR, X- ray electron spectroscopy (XPS), electron spin resonance (ESR) and nuclear magnetic resonance (NMR) spectroscopy, elemental analysis, thermal stability, and electrical conductivity. The poly(2-aminophenol) presented a higher copper(II) content than that of poly(3-aminophenol), moreover as shown by ESR measurements, Cu appears homogeneously dispersed in the former, poly(2-amino phenol), while it seems not to be the case in the latter. The electrical conductivity did not depend on the conditions of synthesis as well as of the hydroxyl groups position. The results indicate that the polymers have several branched rings and their thermal stability increased by the presence of the copper ions into the polymer matrix. Received: 7 August 2002/Revised version: 8 November 2002/ Accepted: 12 November 2002 Correspondence to B. L. Rivas  相似文献   

9.
The electrically conducting polyfuran/poly(2‐iodoaniline) (PFu/P2IAn) and P2IAn/PFu composites were prepared by chemical oxidative polymerization using polyfuran and poly(2‐iodoaniline) in HCl and CHCl3 media. The conductivities of composites were determined as a function of the amount of guest polymer. It was found out that the conductivities of P2IAn/PFu composites increased 100‐fold, whereas the conductivities of PFu/P2IAn composites did not show a specific increase. The composite compositions were altered by varying guest polymer feed ratios during preparation. Generally, the electrical conductivities of P2IAn/PFu composites increased with increasing the amount of PFu. Homopolymers and composites were further characterized thermally, employing thermogravimetry (TGA) and morphologically employing scanning electron microscopy (SEM). Further evidences concerning the polymer structures were obtained by FTIR and UV‐vis spectroscopies and magnetic susceptibility measurements. TGA results revealed that PFu/P2IAn among the homopolymers (PFu and P2IAn) and P2IAn/PFu composite have the highest thermal stability. The composites synthesized varying the host and the guest polymer order have different conductivities, morphological structures, and thermal properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2823–2830, 2003  相似文献   

10.
The synthesis of copolymers from different feed ratios of N-(methacryloyloxymethyl) benzotriazole (MMBT) and glycidyl methacrylate (GMA) was achieved by using free radical solution polymerization technique and characterized using FT-IR and 13C NMR spectroscopy. The thermal stability of the synthesized copolymers was studied using thermogravimetric analysis (TGA). The corrosion performances of mild steel specimens dip coated with different composition of copolymers were investigated in 0.1 M HCl using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) method. The polarization and impedance measurements showed different corrosion protection efficiency with change in composition of the copolymers. It was found that the corrosion protection properties are owing to the barrier effect of the polymer layer covered on the mild steel surfaces. However, it was observed that the copolymer obtained from 1:1 mole ratio of MMBT and GMA exhibited better protection efficiency than other combinations.  相似文献   

11.
The syntheses of thermally stable, conducting polyaniline, poly(3-fluoroaniline), and poly(aniline-co-3-fluoroaniline) derivatives by chemical oxidative polymerization methods are described. By varying the mol% of 3-fluoroaniline in the monomer feed, a series of new poly(aniline-co-3-fluoroaniline) derivatives with different chemical compositions were prepared by chemical oxidative copolymerization methods using ammonium persulfate as oxidant in the presence of hydrochloric acid as the dopant. The chemical oxidative copolymerization of aniline with 3-fluoroaniline affords poly(aniline-co-3-fluoroaniline) derivatives with increased solubility properties, greater thermal stability, improved morphological control, and enhanced electrical characteristics, which promotes the processibility of the different fluorine-functionalized polyaniline derivatives when compared with the parent polyaniline homopolymer.

Poly(3-fluoroaniline) and the different poly(aniline-co-3-fluoroaniline) derivatives show better solubility and thermal stability than the polyaniline homopolymer, due to the incorporation of the F atoms along the fluorine-functionalized polyaniline backbone. Furthermore, the poly(3-fluoroaniline) homopolymer is thermally more stable than the polyaniline homopolymer due to the presence of the C–F bonds of the 3-fluoroaniline units along the polymer backbone. The electrical conductivity of the different poly(3-fluoroaniline) derivatives is dependent on the 3-fluoroaniline content in the polymer derivative and the morphology of the specific copolymer. The poly(3-fluoroaniline) homopolymer exhibits the lowest electrical conductivity. In addition, the electrical conductivity of the different poly(aniline-co-3-fluoroaniline) derivatives decreases with increasing 3-fluoroaniline content in the copolymer. The different polymer derivatives were characterized by proton nuclear magnetic resonance (1H NMR) spectrometry, fourier transform infrared (FTIR) spectroscopy, ultraviolet visible (UV–Vis) spectroscopy, thermogravimetric analyses, scanning electron microscopy, and electrical conductivity measurements.  相似文献   


12.
Radical copolymerization of N-isopropylacrylamide (NIPA) with N-vinyl-2-pyrrolidone (VP) were carried out with 2,2′-azobisisobutyronitrile (AIBN) as an intiator in N,N′-dimethylformamide solution at 65°C under nitrogen atmosphere. Compositon of the copolymers synthesized in a wide range of monomer feed ratios were determined by FTIR and 1H (13C) NMR-DEPT-135 spectroscopy. The monomer reactivity ratios were determined by Fineman-Ross, Kelen-Tüdös and non-linear regression methods. It was observed that the studied monomer pair has some tendency to alternation in the chosen monomer feed ratios due to formation of intermolecular interaction through H-bonding and N → O = C coordination. The synthesized poly(NIPA-co-VP)s show temperature sensitivity (T s), higher glass-transiton temperature (T g ), thermal stability, polyelectrolyte and stimuli-responsive (temperature- and pH-sensitive) behavior and can be attributed to the class of bioengineering functional copolymers useful for application in various gene- and bioengineering processes, drug delivery systems and biomacromolecule conjugations.  相似文献   

13.
Electrochemical copolymerization of o‐dihydroxybenzene (oDHB) and 3‐methylthiophene (3MeT) was successfully achieved in boron trifluoride diethyl etherate by direct anodic oxidation of the monomer mixtures, although the oxidation potentials of oDHB and 3MeT were quite different. The influence of the applied polymerization potential on the synthesis of the copolymers was investigated. The higher applied potential favored the incorporation of 3MeT units into the copolymers. The structure and properties of the copolymers were investigated with UV‐vis spectroscopy, fluorescence spectroscopy, FTIR spectroscopy, and thermal analysis. The novel copolymers had many advantages, including good redox activity, good thermal stability, and high electrical conductivity. Additionally, the copolymers fluorescence properties that were tunable through changes in the feed ratio of the monomer mixtures. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

14.
Polyaniline, poly(aniline‐co‐4,4′‐diaminodiphenylsulfone), and poly(4,4′‐diaminodiphenylsulfone) were synthesized by ammonium peroxydisulfate oxidation and characterized by a number of techniques, including infrared spectroscopy, ultraviolet–visible absorption spectroscopy, 1H‐NMR, thermogravimetric analysis, and differential scanning calorimetry. These copolymers had enhanced solubility in common organic solvents in comparison with polyaniline. The conductivities of the HCl‐doped polymers ranged from 1 S cm?1 for polyaniline to 10?8 S cm?1 for poly(4,4′‐diaminodiphenylsulfone). The copolymer compositions showed that block copolymers of 4,4′‐diaminodiphenylsulfone (r1 > 1) and aniline (r2 < 1) formed and that the reactivity of 4,4′‐diaminodiphenylsulfone was greater than that of aniline. The results were explained by the effect of the ? SO2? group present in the polymer structure. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2337–2347, 2003  相似文献   

15.
This article reports the synthesis and characterization of copolymers based on aniline and substituted anilines by using dodecylbenzene sulfonic acid as a dopant. The copolymers were soluble in organic solvents, such as methanol, ethanol, isopropanol, N‐methylpyrrolidinone, dimethylsulphoxide, and have conductivity of the order of 1.5 to 10?7 S/cm depending upon the monomer ratios and extent of dopant used. The effect of substituents like 2‐methyl, 2‐ethyl, and 2‐isopropyl groups on the electrochemical, conductivity, thermal stability, solubilization, and spectroscopic behavior of the copolymers has been evaluated. The composition of the copolymers was determined by 1H‐NMR spectroscopy. Corrosion inhibition behavior of the copolymers in 1.0N HCl has been evaluated using linear polarization resistance method and Tafel extrapolation method. The corrosion efficiency depends upon the copolymer composition and it increased with increasing amount of 2‐alkyl aniline in the feed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

16.
A kind of novel conducting copolymer with different compositions based on aniline and 2-aminobenzyl alcohol was prepared by chemical oxidative polymerization method. The copolymers were characterized by the methods of FT-IR, UV–Vis, XRD and DSC. It indicated that 2-aminobenzyl alcohol could copolymerize with aniline by this method. In addition, the solubility and conductivity of the copolymers were also studied in detail. The results showed that the copolymers had better solubility in pyridine than pure HCl doped polyaniline and the conductivities were decreased with the increase of the molar ratio of 2-aminobenzyl alcohol in copolymer.  相似文献   

17.
The aim of this investigation was the copolymerization of a chiral monomer, (R)‐N‐(1‐phenylethyl) methacrylamide, with an achiral monomer, 2‐hydroxyethyl methacrylate (HEMA). The copolymerization characteristics as well as the chiroptical properties (optical rotation and circular dichroism) and their variation with copolymer composition and temperature are discussed. The copolymers are statistical and enriched in HEMA. The monomer reactivity ratio of the chiral monomer (r1) is 0.133 whereas that of HEMA (r2) is 1.042 based on the Kelen–Tudos method. The sequence of consecutive chiral monomer units predominates for a feed composition between 0.5 and 0.9 (mole fraction). On the other hand, the sequence of HEMA is uniform and it predominates for a feed composition of around 0.5 (mole fraction). The chiroptical properties of the copolymers do not vary linearly with the content of chiral units in the copolymers. The optical rotation and circular dichroism attain optimum values above 30–40 mol% of chiral monomer units in the copolymers. However, the circular dichroism of the copolymers varies linearly with the temperature. The chiral monomer being a more bulky structure is less reactive than HEMA. The nonlinear variation of chiroptical properties of the copolymers with the content of chiral units may be due to the secondary interaction in the copolymers associated with the hydrogen bonding involving the amide linkage (CONH) present in the pendant chromophore of the chiral monomer as well as the hydroxyl pendant group of HEMA and also the aromatic π–π interaction. Copyright © 2009 Society of Chemical Industry  相似文献   

18.
Poly[methacryloxypropylheptacyclopentyl‐T8‐silsesquioxane (MAPOSS)‐co‐3‐methacryloxypropyltris(trimethylsiloxy)silane (SiMA)] was synthesized through free radical polymerization. The physical and carbon dioxide (CO2) sorption properties of the copolymer membranes were investigated in terms of the MAPOSS content. As the MAPOSS content increases, the membrane density increased, suggesting a decrease in the fractional free volume. In addition, the thermal stability was improved with increasing the MAPOSS content. These are because of the polyhedraloligomericilsesquioxane (POSS) units that restrict the high mobility of poly(SiMA) segments. The glass transition temperature, Tg of the copolymers was single Tg based on the differential scanning calorimetry, suggesting that the copolymers were random and not phase separation. Based on the CO2 sorption measurement, the POSS units play a role in reducing Henry's dissolution by suppressing the mobility of the poly(SiMA) component, while POSS units increase the nonequilibrium excess free volume, which contributes to the Langmuir dissolution. Based on these results, the introduction of MAPOSS unit is one of the effective ways to improved the thermal stability and CO2 sorption property due to the enhancement of the polymer rigidity. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

19.
Poly(ether sulfone) and poly(ether sulfone ketone) copolymers (I–V) were synthesized by the nucleophilic substitution reaction of 4,4′-dihydroxy diphenyl sulfone (DHDPS, A) with various mole proportions 4,4′-difluoro benzophenone (DFBP, B) and 4,4′-difluoro diphenyl sulfone (DFDPS, C) using sulfolane as solvent in the presence of anhydrous K2CO3. The polymers were characterized by physicochemical and spectroscopic techniques. All polymers were found to be amorphous, and the glass transition temperature (Tg) was found to increase with the sulfonyl content of the polymers. 13C-nuclear magnetic resonance (NMR) spectral data was interpreted in terms of the compositional triads, BAB, BAC, CAC, ABA, and ABB, and indicate that transetherification occurs at high concentration of DFBP units in the polymer (IV). The good agreement between the observed and calculated feed ratios validates the triad analysis. Thermal decomposition studies reveal that the thermal stability of the polymers increases with increase in the carbonyl content in the polymer. Activation energies for thermal decomposition were found to be in the range of 160–203 kJ mol−1 with the cleavage of ϕ SO2 bond being the preponderant mode of decomposition and depended on the block length of the sulfonyl unit. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2113–2121, 1999  相似文献   

20.
Summary p-(2-Methacryloyloxyethoxy)-N-(4-stilbenzylidene)aniline 6 was prepared by the reactions of methacryloyl chloride with p-(2-hydroxyethoxy)-N-(4-stilbenzylidene)aniline 5. Monomer 6 was polymerized with radical initiators to obtain polymer with p-oxy-N-4-(stilbenzylidene)aniline, which is presumably effective chromophore for second-order nonlinear optical applications in the side chain. The resulting polymethacrylate 7 showed a thermal stability up to 300 °C in TGA thermogram, and the Tg value obtained from DSC thermogram was 166°C, which is acceptable for NLO device applications.  相似文献   

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