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1.
This work describes three different methods for detecting acidic groups copolymerized in poly(methyl methacrylate), poly(ethyl methacrylate), and poly(n‐butyl methacrylate) chains using molecular spectroscopy. The first was based on the shift of the tautomeric equilibrium of 4‐dimethylaminoazobenzene by acidic groups that modify the absorption band in the UV/vis spectra. We also show that the acidic groups present in the polymer influenced the anti‐syn photoisomerization reaction of this dye. Further, a mercury–dithizonate complex was completely bleached when sorbed in poly(n‐alkyl methacrylate) matrices containing acidic groups. Finally, Nile Blue A was used as a spectrophotometric probe to quantify the amount of acidic groups in these polymers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 830–838, 2004  相似文献   

2.
In this study, poly(o‐anisidine) [POA], poly(o‐anisidine‐co‐aniline) [POA‐co‐A], and polyaniline [PANi] were chemically synthesized using a single polymerization process with aniline and o‐anisidine as the respective monomers. During the polymerization process, p‐toluene sulfonic acid monohydrate was used as a dopant while ammonium persulfate was used as an oxidant. N‐methyl‐pyrolidone (NMP) was used as a solvent. We observed that the ATR spectra of POA‐co‐A showed features similar to those of PANi and POA as well as additional ones. POA‐co‐A also achieved broader and more extended UV–vis absorption than POA but less than PANi. The chemical and electronic structure of the product of polymerization was studied using Attenuated Total Reflectance spectroscopy (ATR) and UV–visible spectroscopy (UV–vis). The transition temperature of the homopolymers and copolymers was studied using differential scanning calorimetry and the viscosity average molecular weight was studied by using dilute solution viscometry. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

3.
In this study, an acrylate elastomer with light‐stable functional groups was synthesized by methyl methacrylate (MMA), butyl acrylate (BA), and a polymerizable UV stabilizer 2‐hydroxy‐4‐(3‐methacryloxy‐2‐hydroxylproroxy) benzophenone (BPMA) via emulsion polymerization, and the product was poly[methyl methacrylate‐co‐butyl acrylate‐co‐2‐hydroxy‐4‐(3‐methacryloxy‐2‐hydroxylproroxy) benzophenone] [poly(MMA‐co‐BA‐co‐BPMA)]. The composition and characteristics of poly (MMA‐co‐BA‐co‐BPMA) were determined by using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H‐NMR), and ultraviolet–visible absorption spectroscopy (UV–vis). Further, the obtained poly(MMA‐co‐BA‐co‐BPMA) was blended with polyoxymethylene (POM) to modify its photostabilization, as well as the mechanical properties of POM composite were tested before and after UV irradiation. The result showed that poly(MMA‐co‐BA‐co‐BPMA) can be dispersed well in the POM matrix, which could play a role of improving compatibility with and toughening for POM, and its light‐stable functional groups could increase the UV resistance of POM composite. Mechanical properties of modified POM were kept well with higher impact strength and elongation at break than pure POM after UV irradiation. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

4.
A new‐type of dicarboxylic acid was synthesized from the reaction of 2,5‐bis(4‐aminobenzylidene)cyclopentanone with trimellitic anhydride in a solution of glacial acetic acid/pyridine (Py) at refluxing temperature. Six novel heat resistance poly(amide‐imide)s (PAIs) with good inherent viscosities were synthesized, from the direct polycondensation reaction of N,N′‐[2,5‐bis(4‐aminobenzylidene)cyclopentanone]bistrimellitimide acid with several aromatic diamines, by two different methods such as direct polycondensation in a medium consisting of N‐methyl‐2‐pyrrolidone (NMP)/triphenyl phosphite (TPP)/calcium chloride (CaCl2)/pyridine (Py) and direct polycondensation in a p‐toluene sulfonyl chloride (tosyl chloride, TsCl)/pyridine (Py)/N,N‐dimethylformamide (DMF) system. All of the above polymers were fully characterized by 1H NMR, FTIR, elemental analysis, inherent viscosity, solubility tests, UV‐vis spectroscopy, differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), and derivative of thermaogravimetric (DTG). The resulted poly(amide‐imide)s (PAIs) have showed admirable good inherent viscosities, thermal stability, and solubility. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

5.
A living functionalization method for group transfer polymerization (GTP) has been developed for poly(alkyl methacrylates) using the sterically hindered monomer, methyl-2-phenylpropenoate (MPHA). The end-capping reactions of MPHA with living trimethylsilyl ketene acetal-ended poly(methyl methacrylate) (PMMA) chain ends have been systematically studied and characterized by size exclusion chromatography, vapor pressure osmometry, ultraviolet-visible, 1H and 13C nuclear magnetic resonance spectroscopy. Although oligomerization of MPHA is observed at - 78° C, this is reversible and only monoaddition is observed at room temperature. In principle, various functional groups can be introduced into poly(alkyl methacrylates) via substituents on the aromatic ring of MPHA and related monomers. Amino-functionalized PMMA was prepared by end-capping reactions of living trimethylsilyl ketene acetal-ended PMMA with methyl E-3-(2-dimethylaminophenyl)-2-phenylacrylate.  相似文献   

6.
A new thermally stable aromatic poly(benzimidazole-amide)s PBIAs was synthesized by low-temperature polycondensation of bis-benzimidazole diamines; 1,4-bis(5-amino-1H-benzimidazol-2-yl)benzene (3a) and 1,3-bis(5-amino-1H-benzimidazol-2-yl)benzene (3b) with two different diacid chlorides. Diamines 3a and 3b were prepared via direct condensation of 1,2-phenylene diamine and terephthalic or isophthalic acid in polyphosphoric acid in high yield. Chemical structures of synthesized monomers were confirmed by elemental analyses and spectroscopic methods. The structures of synthetized polymers were confirmed by FT-IR, 1H-NMR, elemental and thermogravimetric analysis (TGA), X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Thermal stability of the polymers was ascertained via 10 % weight loss temperatures in the range of 315–380 °C (inert atmosphere). Existence of benzimidazole moieties in polymer’s structure makes them suitable for easy coordination to Lewis acids or metallic ions, whereas the substitution of C–H or N–H protons allows for the synthesis of complex derivatives. As a result, a series of novel nanocomposites, via metal complexation of PBIA6a due to their great solubility with Ag+ or Cu2+ cations followed by reduction to metals by sodium borohydride (NaBH4), was prepared. The resulting nanocomposites’ structures were confirmed by FT-IR, XRD, TGA, UV/vis, FE-SEM, TEM and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM–EDX). The FE-SEM, TEM and SEM–EDX results indicated that Cu and Ag particles were dispersed homogenously in nano scale in the polymer matrix.  相似文献   

7.
The polymeric blend was fabricated with crystalline poly(vinylidene fluoride) (PVDF)/amorphous functionalized-poly(methyl methacrylate) (PMMA) in 70/30 w/w ratio by chemical mixing method. Functionalization of PMMA was achieved with 2-amino-5-nitrobenzoic acid. The prepared polymer blend was used as a matrix to synthesize nanocomposites with undoped/doped zinc oxide (ZnO) nanoparticles. Doping in ZnO was achieved with vanadium, sulfur, and dysprosium elements as a dopant. The structural, optical, electronic, and morphological properties of undoped/doped nanosized ZnO and blended nanocomposites were accessed through sophisticated analytical techniques, that is, Fourier transform infrared (FTIR), ultraviolet–visible (UV–vis), UV–vis–diffuse reflectance spectra, nuclear magnetic resonance, fluorescence spectroscopy, X-ray diffraction (XRD), transmission electron microscopy, and scanning electron microscopy. The FTIR band at 1165–1176 cm−1 in functionalized-PMMA indicate the formation of aliphatic C-N bond along with aromatic 1H chemical shift (δ) at 7.134, 7.829 and 8.210 ppm confirm the successfully functionalization of PMMA. The prominent XRD peak at 2θ = 20.8° in nanocomposites shown improvement in β-phase of PVDF. The results show that Dy doped ZnO nanoparticles create remarkable effect on various properties of nanocomposites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47116.  相似文献   

8.
The three‐step reactions of ethyl 4‐aminobenzoate, formic acid, and halohydrocarbons afforded 10 N‐substituted‐N,N′‐diaryl‐formamidine derivatives ( F1 – 10 ) as ultraviolet absorbers. These N‐substituted formamidines were characterized by 1H NMR, 13C NMR, FT‐IR, and ESI‐MS spectroscopies. The UV–vis absorbance and fluorescence properties of the compounds F1 – 10 were investigated in different solvents and in the presences of different metal ions. The effects of the amount of Al3+, Pb2+, Zr4+ ions on the UV–vis absorbance and fluorescence properties of compound F1 were also investigated. Moreover, the thermal stability of the compounds F1 – 10 was evaluated as well as the intermediate N,N′‐bis(4‐ethoxycarbonylphenyl)‐formamidine. J. VINYL ADDIT. TECHNOL., 25:E108–E113, 2019. © 2019 Society of Plastics Engineers  相似文献   

9.
Ferrocene‐substituted conducting polymer namely poly(trans‐1‐(4‐methyl‐3′‐thienyl)‐2‐(ferrocenyl)ethene‐co‐3,4‐ethylenedioxythiophene) [P(MTFE‐co‐EDOT)] was synthesized and its electrochromic properties were studied. Monomer, MTFE, was obtained using 2‐(ferrocenyl)ethene and 3‐methyl‐4‐bromothiophene. The structure of monomer was determined via Fourier transform infrared spectroscopy (FTIR), 1H‐NMR, and 13C‐NMR techniques. The copolymer was synthesized using this monomer and EDOT. The resulting copolymer P(MTFE‐co‐EDOT) was characterized by cyclic voltammetry, FTIR, scanning electron microscopy, atomic force microscopy, and UV–vis spectroscopy. The conductivity measurements of copolymer and PEDOT were accomplished by the four‐probe technique. Although poly(trans‐1‐(4‐methyl‐3′‐thienyl)‐2‐(ferrocenyl)ethene) [P(MTFE)] reveals no electrochromic activity, its copolymer with EDOT has two different colors (violet and gray). Band gap (Eg) and λmax of P(MTFE‐co‐EDOT) were determined. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

10.
A new electrochoromic polymer poly(8,11‐bis(3,4‐ethylenedioxy thiophen‐2‐yl)acenaphtho[1,2‐b]‐quinoxaline) (PBEAQ) was synthesized by electrochemical polymerization of the corresponding monomer (BEAQ) in a 0.1 M tetraethylammonium tetrafluoroborate (TEABF4) dichloromethane–acetonitrile (2 : 1, v : v) solution. The monomer and polymer were characterized by elemental analysis, 1H‐NMR, IR, and UV‐vis spectroscopy. The electrochemical and optical properties of polymer were investigated by cyclic voltammetry and UV‐vis spectroscopy. Cyclic voltammetry and spectroelectrochemistry studies demonstrated that the polymer can be reversibly reduced and oxidized (both n‐ and p‐doped) between ?2 V and +1.5 V vs. Ag/Ag+. The polymer had a transmissive light blue color in the oxidized state and reddish color in the reduced state. Undoped polymer shows UV‐vis absorption peaks at 615 nm in solution, 650 nm in solid state, and has an optical band gap of 1.5 eV. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

11.
Graphene oxide (GO) was modified by in situ esterification reaction with isopentenol polyoxyethylene ether (IPEG) to obtain GO precursor (GO-IPEG) with some polymerization activity. GO-modified polycarboxylic (GO-PCE) was prepared by GO-IPEG and acrylic acid (AA) using the method of in situ polymerization. The molecular structure of GO-IPEG and GO-PCE was characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectra, and nuclear magnetic resonance (NMR). The dispersion properties and dispersion stability of GO-IPEG and GO-PCE in water solution were studied by ultraviolet–visible (UV–vis) absorption spectra, zeta potential, and atomic force microscope. The results of FTIR, Raman, 1H-NMR, and 13C-NMR indicate that IPEG was successfully grafted onto the surface of GO and then fabricated with AA by in situ free-radical polymerization. The results of UV–vis and zeta potential show that GO nanosheets have a better dispersion in GO-IPEG or GO-PCE system when the reaction time of GO and IPEG is 1 h, and the dispersion stability can reach up to 1 month. The better dispersion and application property are confirmed by atomic force microscopy image and cement fluidity, water reducing rate, and compression strength. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48316.  相似文献   

12.
Interactions between poly(maleic anhydride‐alt‐acrylic acid), [poly(MA‐alt‐AA)] and Cu2+, Ni2+, and Cd2+ ions were studied by UV–vis spectroscopy and viscosimetry. Effects of nature and the concentrations of the metal ions on the complex formation were investigated and the formation constants of each complex were determined by the mole‐ratio method. UV–vis studies showed that the complex formation tendency increased in the followed order: Cd(II) < Ni(II) < Cu(II). This order was confirmed by the Irving–William series and the Pearson's classification. The influence of metal ions on the reduced viscosity of poly(MA‐alt‐AA) increased in the following order: Cu(II) < Ni(II) < Cd(II), and this result was explained by the concentration effect. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2698–2705, 2004  相似文献   

13.
Aromatic diamine monomers, including o‐phenylenediamine (oPD), 4‐methyl‐o‐phenylenediamine (4Me‐oPD), 4,5‐dimethyl‐o‐phenylenediamine (dMe‐oPD) and 4‐(tert‐butyl)‐o‐phenylenediamine (tBu‐oPD), were polymerized by chemical oxidation using ammonium persulfate as an oxidant. Aluminium triflate (Al(OTf)3) was also used for the first time as a co‐catalyst under various reaction conditions for the polymerization of oPD derivatives. The polymerization yield was improved when Al(OTf)3 was introduced to the polymerization reaction for most polymers. The solubility of poly(4‐methyl‐o‐phenylenediamine) (P(4Me‐oPD)), poly(4,5‐dimethyl‐o‐phenylenediamine) (P(dMe‐oPD)) and poly(4‐(tert‐butyl)‐o‐phenylenediamine) (P(tBu‐oPD)) polymers was improved compared with the poly(o‐phenylenediamine) (P(oPD)) polymers in most common solvents. The homopolymers obtained were characterized by Fourier transform IR spectroscopy, UV?visible spectroscopy, 1H and 13C NMR, wide‐angle X‐ray diffraction, DSC and TGA. The results showed that the yield, solubility and structure of the polymers are significantly dependent on the polymerization conditions. DSC measurements indicated that the polymers exhibited melting and crystallization transitions. The polymers also showed good thermal stability and decompose above 400 °C in nitrogen. © 2013 Society of Chemical Industry  相似文献   

14.
A series of optically active polyamides containing di‐O‐methyl‐L ‐tartaryl moieties in the main chain were synthesized by polycondensation of di‐O‐methyl‐L ‐tartaryl chloride 5 with diamines and characterized by gel permeation chromatography, UV–vis, circular dichroism (CD), IR, and NMR spectroscopies. The polycondensation reaction could be carried out under mild conditions and the reaction time was short (2–3 h). The key monomer 5 prepared from L ‐tartaric acid via esterification, etherification, hydrolysis, and chlorination was easily purified by vacuum sublimation. These polyamides with number average molecular weights ranging from 14,000 to 35,000, displayed large optical activity in dimethyl sulfoxide solution, and their specific optical rotations oscillated between 87.2° and 210.7° depending on the structures of the diamines. The glass transition temperatures of these polyamides were in the range of 106–191°C, and the 10% mass loss occurred at temperature above 300°C. The polyamides derived from aromatic diamines exhibited higher Tg and thermal stability than those derived from aliphatic diamines. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

15.
The layer‐by‐layer self‐assembly technique was used to fabricate a series of multilayer thin films with poly[4′‐(4‐methacryloyphenyl)‐2,2′:6′,2″‐terpyridine] (PmPhtpy), polycyanofullerenes, and transition metals (Ni2+ and Co2+). The polymer PmPhtpy was prepared by free‐radical polymerization, and this was confirmed by Fourier transform infrared (FTIR) and 1H‐NMR spectroscopy. The polycyanofullerenes, which were characterized by FTIR, ultraviolet–visible (UV–vis), and 13C‐NMR spectroscopy, was synthesized via the bromination of fullerene and then substitution with a nucleophilic reagent [potassium cyanide (KCN)]. The optical properties of the films were measured by attenuated total reflection infrared and UV–vis spectroscopy, and the results indicate that the driving force of the fabrication of the multilayer film was the coordination interaction. The magnetic behavior was examined as a function of the magnetic field strength at 5 K and the temperature (5–300 K). The magnetic hysteresis loops of the films showed a typical S shape at 5 K; this suggested soft ferromagnetic properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40681.  相似文献   

16.

In this work, four novel different alkyl lactate methacrylate monomers were synthesized through azeotropic esterification method by reacting methyl, ethyl, propyl and butyl lactates with methacrylic acid. The prepared monomers were polymerized through solution polymerization technique and both monomers and polymers were analyzed by FTIR, 1H NMR and 13C NMR spectroscopy techniques to elucidate the structure and to confirm their formation. Increasing the number of methylene units in alkyl lactate side chain decreases the glass transition temperature (Tg) of the polymers. Average molecular interchain spacing (〈R〉) of polymers was obtained from the wide-angle X-ray diffraction measurement and the values ranged from 6.26 to 7.18 Å based on the length of alkyl lactate group. The prepared polymers showed hygroscopic property and their moisture absorption was in the range of 10–24% (w/w) depending upon the length of alkyl lactate moiety, relative humidity and time. These polymers have the potential for hydrogel applications owing to their increased moisture absorption capacity. Both polymethyl and propyl lactate methacrylate showed two distinct and prominent thermal degradations whereas polyethyl and butyl lactate methacrylates showed only a single distinct and prominent thermal degradation step. An interesting result of as-synthesized polymers showed odd–even chain length effect in the properties of 〈R〉, moisture uptake and thermal stability.

  相似文献   

17.
A silane‐containing diamine, bis(p‐aminophenoxy) diphenylsilane (BADPS), was prepared by the condensation of p‐aminophenol with dichlorodiphenyl silane in the presence of triethylamine. Then, BADPS was condensed with 4,4‐azobis(4‐cyanopentanoyl chloride) to prepare macroazoinitiators containing silane units (Si–MAIs). A series of poly(methyl methacrylate) gels containing silane were derived by the solution free‐radical crosslinking copolymerization of methyl methacrylate and ethylene glycol dimethacrylate monomers initiated by these macroazoinitiators at a total monomer concentration of 6 mol/L and 80°C. Si–MAIs were characterized with 1H‐NMR and 13C‐NMR spectroscopy, and the structural characteristics of the gels were also examined. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

18.
2,7-dibromo-9,9-bis(perfluorohexylethyl propionate) fluorene was synthesized by Michael addition reaction using 2,7-dibromofluorene and perfluorohexyl ethyl acrylate as the reactants. 9,9-Bis(perfluorohexylethyl propionate) fluorene copolymers were then synthesized by Suzuki coupling reaction with 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborane-diyl)-9,9 -dioctyl fluorene, 2,7-dibromo-9,9-dioctyl fluorene and 2,7-dibromo-9,9-bis(perfluorohexylethyl propionate) fluorene as the monomers. The fluorinated fluorene copolymers were characterized and investigated via Fourier infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance spectroscopy (1HNMR), ultraviolet absorption spectroscopy (UV–vis), cyclic voltammetry (CV) and photoluminance spectroscopy (PL). Because of the long fluorine-containing alkyl side chain, the ultraviolet absorption peak of 9,9-bis(perfluorohexylethyl propionate) fluorene is blue-shifted compared with poly(9,9-dioctylfluorene)(PF8). The LUMO energy level increases and the energy band gap of copolymers widens. Due to the self-assembly of the long fluoroalkyl side chain, the photoluminance spectra of 9,9-bis(perfluorohexylethyl propionate) fluorene copolymers exhibit a new excimer emission peak at 550 nm. The photoluminance stabilities of the copolymers under irradiation and humid conditions are significantly improved due to protective effect from the long fluoroalkyl side chain. After being irradiated under 500 W iodine tungsten lamp or kept under 70% relative humid conditions, the 9,9-bis(perfluorohexylethyl propionate) fluorene copolymers showed much better photoluminance stability than that of poly(9,9-dioctylfluorene) (PF8). These show that introducing long fluoroalkyl side chain into conjugated polymer main chain is a promising strategy to improve environmental stability of devices based on organic conjugated polymers.  相似文献   

19.
The reaction of 4‐(3‐hydroxynaphthalene)‐1,2,4‐triazolidine‐3,5‐dione ( 3HNTD ) with n‐propylisocyanate was performed at different molar ratios. The resulting monosubstituted urea and disubstituted urea‐urethane derivatives were obtained in high yields and were used as model compounds for polymerization reactions. 3HNTD as a monomer was used in the preparation of heterocyclic poly(urea‐urethane)s to produce photoactive polymers, by polycondensation with different diisocyanates in N,N‐dimethylacetamide (DMAc) solution. Chromophoric heterocyclic polymers containing naphthalene group, obtained in quantitative yields, possessed inherent viscosities in the range of 0.14–0.38 dL/g. The resulting poly(urea‐urethane)s is insoluble in most organic solvents, but easily soluble in polar solvents such as dimethyl sulfoxide (DMSO), DMAc, and N‐methylpyrrolidone (NMP). The polymers were characterized by IR, 1H‐NMR, elemental analysis, and TGA. Fluorimetric and UV–vis studies of the monomer as well as polymers were performed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

20.
Hyperbranched poly(silyl ester)s were synthesized via the A2 + B4 route by the polycondensation reaction. The solid poly(silyl ester) was obtained by the reaction of di‐tert‐butyl adipate and 1,3‐tetramethyl‐1,3‐bis‐β(methyl‐dicholorosilyl)ethyl disiloxane. The oligomers with tert‐butyl terminal groups were obtained via the A2 + B2 route by the reaction of 1,5‐dichloro‐1,1,5,5‐tetramethyl‐3,3‐diphenyl‐trisi1oxane with excess amount of di‐tert‐butyl adipate. The viscous fluid and soft solid poly(silyl ester)s were obtained by the reaction of the oligomers as big monomers with 1,3‐tetramethyl‐1,3‐bis‐β(methyl‐dicholorosilyl)ethyl disiloxane. The polymers were characterized by 1H NMR, IR, and UV spectroscopies, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The 1H NMR and IR analysis proved the existence of the branched structures in the polymers. The glass transition temperatures (Tg's) of the viscous fluid and soft solid polymers were below room temperature. The Tg of the solid poly(silyl ester) was not found below room temperature but a temperature for the transition in the liquid crystalline phase was found at 42°C. Thermal decomposition of the soft solid and solid poly(silyl ester)s started at about 130°C and for the others it started at about 200°C. The obtained hyperbranched polymers did not decompose completely at 700°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3430–3436, 2006  相似文献   

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