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1.
In this study, a new polyorganophosphazene with pendant carbazolyl groups was synthesized, and its structure was characterized by IR, 1H‐NMR, and 31P‐NMR spectroscopy. To understand its carrier photogeneration and transport property, we also studied fluorescence spectra and photovoltage spectra. Fluorescence spectra show that the polymer possesses properties dissimilar to those of PVK. There are only two emission peaks at ≈ 360 nm in its spectra, which coincides with that of the monomer model compound, 9‐ethylcarbazole. This may be because of the influence of the spacer. The results of SPS shows that band–band transition mainly comes from electron π–π* transition, and the polymer is a p‐type semiconductor. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1446–1451, 2001  相似文献   

2.
Copolymerization of methacrylic acid (MAA) and ethyl acrylate (EA) was performed by the emulsion polymerization technique in the presence of a mixture of ionic and nonionic emulsifiers, at 85°C, using potassium persulfate as initiator (0.16 wt % of monomer). The molar ratio of MAA : EA varied between 44 : 56 and 54 : 46 in the monomer feed. Copolymers of MAA and EA were synthesized by incorporating diallyl phthalate (DAP) with varying concentrations (0–1.7 mol % of total monomer) in the feed. A copolymer latex of MAA, EA, and DAP was also prepared by the variable feed process. The intrinsic viscosity and gel content were determined. Copolymers were characterized by IR and NMR spectroscopic techniques. The composition of copolymers was determined by 1H‐NMR spectra and sequential distribution from 13C{1H}‐NMR spectra. The pH of the copolymer emulsion varied between 3 and 10 by addition of aqueous ammonia (23% w/w) and its effect on Brookfield viscosity was studied. The effects of copolymer composition, crosslinking agent concentration in the feed, monomer feed process, polymer solid contents, and shear rate on Brookfield viscosity were studied at pH ~ 8. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1430–1441, 2003  相似文献   

3.
The free‐radical copolymerization of water‐soluble poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) was carried out with a feed monomer ratio of 75:25 mol %, and the total monomer concentration was 2.67M. The synthesis of the copolymer was carried out in dioxane at 70°C with benzoyl peroxide as the initiator. The copolymer composition was obtained with elemental analysis and 1H‐NMR spectroscopy. The water‐soluble polymer was characterized with elemental analysis, Fourier transform infrared, 1H‐ and 13C‐NMR spectroscopy, and thermal analysis. Additionally, viscosimetric measurements of the copolymer were performed. The thermal behavior of the copolymer and its complexes were investigated with differential scanning calorimetry (DSC) and thermogravimetry techniques under a nitrogen atmosphere. The copolymer showed high thermal stability and a glass transition in the DSC curves. The separation of various metal ions by the water‐soluble poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) reagent in the aqueous phase with liquid‐phase polymer‐based retention was investigated. The method was based on the retention of inorganic ions by this polymer in a membrane filtration cell and subsequent separation of low‐molar‐mass species from the polymer/metal‐ion complex formed. Poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) could bind metal ions such as Cr(III), Co(II), Zn(II), Ni(II), Cu(II), Cd(II), and Fe(III) in aqueous solutions at pHs 3, 5, and 7. The retention percentage for all the metal ions in the polymer was increased at pH 7, at which the maximum retention capacity could be observed. The interaction of inorganic ions with the hydrophilic polymer was determined as a function of the pH and filtration factor. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 178–185, 2006  相似文献   

4.
The synthesis of the water‐soluble poly(acrylic acid‐co‐vinylsulfonic acid) at different feed monomer ratios, while maintaining constant the total number of mol, was carried out by radical polymerization. The copolymers were characterized by FTIR and 1H‐NMR spectroscopies. The copolymer composition was determined by its sulfur content and by potentiometric titration. The metal ion binding properties for Ni(II) and Cu(II) in the aqueous phase were studied using the liquid‐phase polymer‐based retention (LPR) technique for two values of ionic strength. For comparison, the retention properties of both homopolymers were included. The complexing ability of the polymer was determined by the relative amount of carboxylic acid groups. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1698–1704, 2003  相似文献   

5.
This study examined the polymerizations of maleic anhydride in solution and in the bulk phase catalyzed by nanocrystalline titania or sodium acetate. Through IR and 1H‐NMR, the monomer and polymer were characterized, and the structure of the polymer was confirmed. Moreover, the polymer molecular weight was measured to be 400–800 in solution and 2000–3000 in the bulk phase. The mechanism of the catalytic polymerization was also investigated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2868–2874, 2003  相似文献   

6.
A polyfunctional organic–inorganic hybrid monomer, methyl‐tri(phenylethynyl)silane (MTPES) could be thermally polymerized by a free radical mechanism to a highly crosslinked structure of interest as a high temperature composite matrix resin. The structural changes during thermal cure process were characterized by fourier transform infrared spectrum and 13C‐CP‐MAS‐NMR spectrum. The disappearance of secondary acetylene stretching band at 2166 cm?1 was used successfully to monitor cure reaction accompanied with the formation of cis‐polyene structure at 1600 and 754 cm?1. The possible cure mechanism of MTPES was also proposed. The pyrolysis of cured MTPES under a stream of argon to 1450°C gave a ceramic in high yield (81%). Thermal conversion of polymer to ceramic was studied by means of X‐ray diffraction, Raman spectrum, and energy dispersive spectrometer analysis. The results showed that pyrolytic products were made up of β‐SiC, graphite, and glassy carbon. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

7.
Ring‐opening metathesis polymerization of dicyclopentadiene catalyzed by TiCl4 · 2L/CH3Li system [where L is tetrahydropyran (1), dioxane, 2,5‐dimethylfuran, or tetrahydrofurfyl alcohol] is reported. The obtained polymer was characterized by IR and 1H‐NMR. These catalytic systems effectively promoted the polymerization reaction. Seven influencing factors are discussed. When the aging temperature was 0°C, the aging time was 90 min, the polymerization temperature was 60°C, Li/Ti was 1.5–2, and the monomer/catalyst molar ratio ranged between 30 and 50, the polymerization reaction catalyzed by complex 1 yielded better results within a shorter period of time. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 662–666, 2001  相似文献   

8.
Castor‐acrylated monomer (CAM) NMR spectral assignments were made utilizing one‐ and two‐dimensional NMR techniques. The unique structure of CAM resulted in several novel chemical environments which were observed in the NMR spectra. Previously published vegetable oil and fatty acid ester NMR peak assignments were insufficient for complete identification of NMR peaks. Definitive peak assignments, particularly in the alkyl and alkene regions, are required for evaluation of CAM as a specialty comonomer in the synthesis of latex polymers for use as waterborne‐coating binders. The NMR peak assignments for CAM will allow the subsequent evaluation of the copolymerizability of CAM as well as the determination as to whether unsaturation is preserved during latex polymer synthesis. 1H‐ and 13C‐NMR spectra of CAM are provided with supporting evidence for the peak assignments and discussion of their relevance. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1850–1854, 2001  相似文献   

9.
Bekir Dizman 《Polymer》2007,48(18):5226-5232
A non-symmetric divinyl monomer with terminal carboxylic acid functionality was readily synthesized from the reaction of ethyl α-hydroxymethylacrylate (EHMA) with maleic anhydride. The new monomer (EHMA-MA) was homopolymerized in both bulk and ethyl acetate using AIBN as an initiator to give cyclopolymers. The synthesis of the monomer and cyclopolymers were followed by 13C NMR, 1H NMR, and FTIR. 1H NMR was also utilized to obtain the degree of cyclization of the polymers, which were found to be 95% or higher in all cases. The molecular weights of the cyclopolymers were around 40-60,000 g/mol as estimated by SEC. The cyclopolymers were thermally stable up to 150 °C. Although the cyclopolymers obtained were not water-soluble; they were soluble in aqueous 1 M NaOH solution. In addition to the carboxylic acid functionality present, the cyclopolymers also had an ethyl ester and a lactone moiety. These functional groups were reacted with hexylamine to obtain a polymer with imide and amide moieties.  相似文献   

10.
This work was committed to the polymerization of hydrophobic ketoethyl methacrylate monomer in aqueous medium in the presence of cyclodextrin, instead of polymerizing the monomer in toxic and volatile organic solvents. For this purpose, a new ketoethyl methacrylate monomer, p‐methylphenacylmethacrylate (MPMA), was synthesized from the reaction of p‐methylphenacylbromide with sodium methacrylate in the presence of triethylbenzylammonium chloride. The monomer was identified with FTIR, 1H and 13C‐NMR spectroscopies. Hydroxypropyl‐β‐cyclodextrin (HPCD) was used to form a water‐soluble host/guest inclusion complex (MPMA/HPCD) with the hydrophobic monomer. The complex was identified with FTIR and NMR techniques and polymerized in aqueous medium using potassium persulfate as initiator. During polymerization the resulting hydrophobic methacrylate polymer precipitated out with a majority of HPCD left in solution and a minority of HPCD bonded on the resulting polymer. The thus‐prepared polymer exhibited little difference from the counterparts obtained in organic solvent in number average molecular weight (Mn), polydispersity (Mw/Mn) and yield. The investigation provides a novel strategy for preparing hydrophobic ketoethyl methacrylate polymer in aqueous medium by using a monomer/HPCD inclusion complex. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

11.
A series of copolymers were prepared by chemically oxidative polymerization of pyrrole (PY) and ortho-toluidine (OT) in HCl aqueous medium. The yield, intrinsic viscosity, and solubility of the copolymers were studied by changing the monomer molar ratio. The resulting PY/OT copolymers were identified by FTIR, 1H–NMR, DSC, and WAXD techniques. The experimental results showed that the oxidative polymerization of pyrrole and o-toluidine is exothermic and the resulting polymers exhibit an enhanced solubility in most organic solvents compared with that of pyrrole homopolymer. The polymer obtained is a real and amorphous copolymer containing pyrrole and o-toluidine units. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 510–518, 2001  相似文献   

12.
Aqueous polymerization of 3‐chloroaniline (mCA) was studied using sodium dichromate as oxidant in the presence of hydrochloric acid. The effect of hydrochloric acid, sodium dichromate and monomer concentration on the polymerization rate, specific viscosity of the obtained polymer and ac conductivity was investigated. The initial and overall reaction rates increase with increasing hydrochloric acid concentration or sodium dichromate concentration, but decrease with increasing monomer concentration. The specific viscosity values (ηsp) increase with increasing hydrochloric acid concentration or monomer concentration, which means that the molecular weight of the polymer samples increases accordingly. On the contrary, the molecular weight decreases with increasing sodium dichromate concentration. The highest ac conductivity value of the obtained polymer was found for 0.0255 mol l−1 of Na2Cr2O7, 0.8 mol l−1 HCl and 0.0956 mol l−1 monomer concentration in the reaction medium. The order of the polymerization reaction with respect to hydrochloric acid, Na2Cr2O7 and monomer concentration was found to be 1.0, 0.9 and 0.75, respectively. The apparent activation energy (Ea) for this polymerization system was found to be 13.674 × 104 mol−1. The obtained poly(3‐chloroaniline) was characterized by UV–visible, IR and 1H NMR spectroscopy. X‐ray diffraction analysis and electron microscopy studies were carried out. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) results were used to confirm the structure. © 2001 Society of Chemical Industry  相似文献   

13.
A novel oligosiloxane containing alternative ladderlike structure involving viologen groups has been prepared via donor–acceptor interaction‐assisted template polymerization. The monomer used as the electron‐donor component, N,N ′‐bis(3‐methyldimethoxyl‐silylpropyl)‐4,4′‐bipyridinium dihexafluorophosphate and its precursor, N,N ′‐bis(3‐methyldimethoxyl‐silylpropyl)‐4,4′‐bipyridinium dibromide were first synthesized successfully in high yield. This oligosiloxane, which displays interesting electrochromic properties, has been characterized by FTIR, UV–vis, 1H NMR, 29Si NMR, X‐ray diffraction (XRD), and vapour pressure osmometry (VPO). © 2001 Society of Chemical Industry  相似文献   

14.
A novel soluble terephthalate‐bridged ladderlike polymethylsiloxane was synthesized successfully by stepwise coupling polymerization in three steps, including hydrosilylation coupling, hydrolysis and polycondensation. The bis(3‐methyldichlorosilylpropyl) terephthalate monomer was first synthesized by hydrosilylation reaction in the presence of dicyclopentadienylplatinum(II) chloride (Cp2PtCl2) catalyst. The structures of the monomer and the polymer were characterized by FTIR, 1H NMR, 13C NMR and 29Si NMR spectroscopy, mass spectrometry, X‐ray diffraction, differential scanning calorimetry, vapour pressure osmometry and gel permeation chromatography. Characterization data indicate that the synthesized polymer possesses an ordered ladderlike structure. © 2000 Society of Chemical Industry  相似文献   

15.
A new V(V)-substituted isopolytungstate, (n-C3H7)5[H4VW11O40], with Keggin structure was synthesized in an acidic aqueous–CH3CN solution and characterized by elemental analysis, FT-IR, Raman, 1H NMR, and cyclic voltammetry.  相似文献   

16.
2-Hydroxy-3-(1-naphthyloxy)propyl methacrylate (NOPMA) monomer was synthesized from reaction of 2-[(2-naphthyloxy)methyl]oxirane with methacrylic acid in the presence of pyridine. The polymerization of NOPMA was carried out by free radical polymerization method in the presence of AIBN at 60 °C. The structure of monomer and polymer was characterized by 1H-NMR, 13C-NMR and FT-IR spectroscopy techniques. The glass transition temperature and average-molecular weights of poly(NOPMA) were measured using differential scanning calorimetry and gel permeation chromatography, respectively. The thermal degradation behavior of poly(NOPMA) has been investigated by FT-IR studies of the partially degraded polymer and thermogravimetry. The cold ring fractions (CRFs) were collected at two different temperatures, initially fraction-1 (CRF1) is from room temperature to 320 °C, and the other fraction-2 (CRF2) is from 320 to 500 °C. The volatile products of the degradation were trapped at ?195 °C (in liquid nitrogen). All the fractions were characterized by FT-IR, 1H and 13C-NMR spectroscopic techniques, and the cold ring fractions (CRFs) were also characterized by GC–MS. For the degradation of polymer, the major compound between products of CRFs is α-naphthol. The GC–MS, FT-IR and NMR data showed that depolymerization corresponding to monomer was not prominent below 320 °C in the thermal degradation of poly(NOPMA). The mode of thermal degradation containing formation of the major products was identified. The dielectric permittivity (ε′), the loss factor (ε″) and conductivity (σac) were measured using a dielectric analyzer in the frequency range of 50 Hz to 20 kHz.  相似文献   

17.
Diethyl-dithiocarbamic acid 2-[4-(2-diethylthiocarbamoylsulfanyl-2-phenyl-acetyl)-2,5-dioxo-piperazin-1-yl]-2-oxo-1-phenyl-ethyl ester as a novel di-functional reversible addition–fragmentation chain transfer (RAFT) agent was synthesized based on 2,5-diketopiperazine. The RAFT agent was designed based on the propagating core (R group) approach and characterized by 1H NMR, 13C NMR, FT-IR, elemental analysis, and melting point technique. Then, ethyl methacrylate was synthesized via free radical and RAFT polymerizations. To investigate the effect of the RAFT agent on the kinetic of polymerization, molecular weight, and polydispersity index (PDI) of polymers and also monomer conversion were monitored. Also, synthesized polymers were characterized by 1H NMR, 13C NMR, FT-IR, and TGA. Characterization analyses of synthesized RAFT agent were consistent with the structure. NMR and FTIR analyses confirmed end group incorporation of RAFT agent into polymer structure. According to results, poly(ethyl methacrylate) with low PDI (1.14) was obtained. Kinetic study indicated well-controlled polymerization of ethyl methacrylate by synthesized RAFT agent. TGA results showed that RAFT agent could reduce termination reactions and so reduce head-to-head bonds and chain-end unsaturation by keeping the concentration of radicals low enough.  相似文献   

18.
Well‐defined comblike atactic polystyrene functionalized with hydroxyl groups was synthesized via living/controlling radical polymerization promoted by metallocene complexes in the presence of poly(phenyl glycidyl ether)‐co‐formaldehyde as the initiator and Sn as a reducing agent. The effect of the polymerization conditions, such as the ratio of initiator to monomer, temperature, and polymerization time, and the structure of the metallocene complex on the polymerization process were investigated. The resulting polymers were characterized by gel permeation chromatography, multiangle laser light scattering, 1H‐NMR, and 13C‐NMR. The results show that the polymer had a narrow molecular weight distribution in the range 1.1–1.4 and the number‐average molecular weight of the polymer linearly depended on the monomer conversion within the polymerization timescale, which confirmed that living radical polymerization characteristics prevailed in the polymerization process. Both the number of arms and the number of hydroxyl groups in each polymer molecule were about four, which suggested that they arose from the epoxy functional groups of the initiator. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

19.
Monomers of diacylated amine were synthesized by the reaction of acryloyl chloride or methacryloyl chloride with p‐phenylenediamine. Heating DMF solution of these monomers at 75°C in the presence of AIBN as an initiator gave the corresponding polymer. The solid metallopolymer complexes with different metal salts were isolated either by the in situ addition of the monomer, metal salt, and initiator at 75°C or by the reaction of the isolated polymer with the metal salt at 150°C. The monomers, polymers, and their metallopolymer compounds were characterized using elemental analysis, IR, NMR (1H and 13C), and MS spectral measurements in addition to thermal analysis. The IR data showed that the coordinating atoms of the polymer are dependent on the reaction temperature. The ion selectivity of the isolated polymers toward different metal ions either for a single metal ion or in a mixture as aqueous solutions are studied by the batch techniques. Energy dispersive spectroscopy (EDS) measurements showed that both polymers are more selective to Hg2+ and Pb2+. The morphology of the polymers and their metallopolymer complexes at different temperature was also studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2412–2422, 2006  相似文献   

20.
A new polymer–drug conjugate based on poly(N-vinylpyrrolidone-co-maleic anhydride) as support and 2-amino-5-(4-methoxy-phenyl)-1,3,4-oxadiazole, having antimicrobial and antifungal activity, was synthesized by Higashi–Yamazaki reaction. The functionalized copolymer having a substitution degree of 29% was fully characterized in terms of chemical structure by 1H NMR, FTIR and UV–Vis spectroscopy, and by molecular weight measurements. The crystallization of CaCO3 particles from saturate aqueous solutions in the presence of the newly synthesized conjugate copolymer, comparative with particles prepared in similar conditions but without polymer, has been investigated. The obtained particles were characterized by scanning electron and polarized optical microscopy, X-ray diffraction, particles charge density, and electrophoresis. These new composite materials are excellent candidates for use in biomedical applications, particularly for drug delivery.  相似文献   

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