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1.
Polyaniline (PANI)‐Ag nanocomposites were synthesized by in situ chemical polymerization approach using ammonium persulfate and silver nitrate as oxidant. Characterizations of nanocomposites were done by ultraviolet–visible ( UV–vis), Fourier transform infrared (FTIR), X‐ray diffraction (XRD), scanning electron microscopy, and transmission electron microscopy (TEM). UV–vis, XRD and FTIR analysis established the formation of PANI/Ag nanocomposites and face‐centered‐cubic phase of silver. PANInanofibers were of average diameter ~ 30 nm and several micrometers in length. Morphological analysis showed that the spherical‐shaped silver nanoparticles decorate the surface of PANI nanofibers. Silver nanoparticles of average diameter ~ 5–10 nm were observed on the TEM images for the PANI‐Ag nanocomposites. Such type of PANI‐Ag nanocomposites can be used as bistable switches as well as memory devices. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

2.
The investigation of clay based polymer nanocomposites has opened the door for the development of novel, ecofriendly advanced nano materials that can be safely recycled. Because of their nanometer size dispersion, these nanocomposites often have superior physical and mechanical properties. In this study, novel nanocomposites of poly(o‐toluidine) (POT) and organically modified montmorillonite (MMT) were synthesized using camphor sulfonic acid (CSA), cetyl pyridinum chloride (CPCl), and N‐cetyl‐N,N,N‐trimethyl ammonium bromide (CTAB) to study the role of surfactant modification on the intercalation. The in situ intercalative polymerization of POT within the organically modified MMT layers was analyzed by FTIR, UV–visible, XRD, SEM as well as TEM studies. The average particle size of the nanocomposites was found to be in the range 80–100 nm. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

3.
A poly(aniline‐co‐pyrrole), using anionic spherical polyelectrolyte brushes (ASPB) as dopant and template, was synthesized by chemical oxidation polymerization. The composites were characterized by scanning electron microscopy (SEM), Fourier‐transform infrared spectrometry (FTIR), X‐ray diffraction (XRD), and electrical studies. The SEM images confirmed that the composites had a spherical‐like structure, with a size of ca. 170 nm. The FTIR spectra showed the intermolecular interaction between poly(aniline‐co‐pyrrole) and ASPB. The XRD analysis revealed that the interplanar distance of the copolymers increased from 0.373 nm to 0.391 nm. The electrical conductivity of the poly(aniline‐co‐pyrrole)/ASPB nanocomposites at room temperature was 8.3 S cm−1, higher than that of the conducting copolymers (2.1 S cm−1). These conductive nanocomposites have nanoparticle size, controllable morphology, and the potential for application in inkjet electronic printing. POLYM. COMPOS., 35:1858–1863, 2014. © 2014 Society of Plastics Engineers  相似文献   

4.
The paper presents the electrostatic charge dissipative performance of conducting polymer nanocomposite impregnated fabric based on polyaniline (PANI) and zinc oxide nanoparticles (ZnO NPs). Conducting polymer nanocomposites (PANI‐ZnO NPs) were synthesized by in situ chemical oxidative polymerization of aniline by using sodium dodecyl sulfate as surfactant and HCl as dopant. Coating of PANI‐ZnO nanocomposites on the cotton fabric was carried out during polymerization. The interaction of ZnO NPs with the PANI matrix was determined by Fourier transform infrared spectra (FTIR), TGA, XRD, scanning electron Microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and conductivity measurements. The conductivity of PANI‐ZnO NP coated fabric was found to be in the range 10?3 ? 10?6 S cm?1 depending on the loading concentration of ZnO NPs in the polymer matrix. TEM and HRTEM images showed that the PANI‐ZnO nanocomposites had an average diameter of 25–30 nm and were nicely dispersed in the polymer matrix. Antistatic performance of the nanocomposite impregnated fabric was investigated by static decay meter and John Chubb instrument. The static decay time of the film was in the range 0.5 ? 3.4 s on recording the decay time from 5000 V to 500 V. This indicated that the nanocomposite based on PANI‐ZnO nanocomposites has great potential to be used as an effective antistatic material. © 2015 Society of Chemical Industry  相似文献   

5.
Differential scanning calorimetry (DSC) of triple blends of high molecular weight poly(N‐vinyl pyrrolidone) (PVP) with oligomeric poly(ethylene glycol) (PEG) of molecular weight 400 g/mol and copolymer of methacrylic acid with ethylacrylate (PMAA‐co‐EA) demonstrates partial miscibility of polymer components, which is due to formation of interpolymer hydrogen bonds (reversible crosslinking). Because both PVP and PMAA‐co‐EA are amorphous polymers and PEG exhibits crystalline phase, the DSC examination is informative on the phase state of PEG in the triple blends and reveals a strong competition between PEG and PMAA‐co‐EA for interaction with PVP. The hydrogen bonding in the triple PVP–PEG–PMAA‐co‐EA blends has been established with FTIR Spectroscopy. To evaluate the relative strengths of hydrogen bonded complexes in PVP–PEG–PMAA‐co‐EA blends, quantum‐chemical calculations were performed. According to this analysis, the energy of H‐bonding has been found to diminish in the order: PVP–PMAA‐co‐EA–PEG(OH) > PVP–(OH)PEG(OH)–PVP > PVP–H2O > PVP–PEG(OH) > PMAA‐co‐EA–PEG(? O? ) > PVP–PMAA‐co‐EA > PMAA‐co‐EA–PEG(OH). Thus, most stable complexes are the triple PVP–PMAA‐co‐EA–PEG(OH) complex and the complex wherein comparatively short PEG chains form simultaneously two hydrogen bonds to PVP carbonyl groups through both terminal OH‐groups, acting as H‐bonding crosslinks between longer PVP backbones. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

6.
Phosphorus, nitrogen‐containing monomer, acryloxyethyl phenoxy phosphorodiethyl amidate (AEPPA), was synthesized and copolymerized with styrene (St). Nanocomposites of polystyrene and poly(St‐co‐AEPPA) with various amounts of Mg‐Al layered double hydroxide (LDH) were then prepared by in situ bulk polymerization. Structure and morphology of the nanocomposites were investigated by Fourier transform infrared (FTIR), X‐ray diffraction (XRD), and transmission electron microscopy (TEM). The nanocomposites were also examined by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and microscale combustion calorimeter (MCC) to evaluate the thermal properties and flammability. Intercalated or exfoliated structures were obtained for all the nanocomposites. The results from XRD and TEM showed the LDH layers dispersed better in poly(St‐co‐AEPPA) than those in PS matrix. Decrease in thermal stability and enhancement in char residues were observed for poly(St‐co‐AEPPA) nanocomposites compared with PS nanocomposites at the same LDH loading. The addition of LDH can obviously reduce the heat release capacity (HRC) and total heat release (THR) of PS. Moreover, further reductions in HRC and THR were found in poly(St‐co‐AEPPA) nanocomposites. The reduction in flammability was attributed to the lower maximum mass loss rate (MMLR) and higher char residues of the nanocomposites. POLYM. COMPOS., 2011. © 2010 Society of Plastics Engineers  相似文献   

7.
Well‐dispersed poly(methyl methacrylate) (PMMA)–bentonite clay composite was synthesized by emulsion polymerization using methyl methacrylate (MMA) monomer and 3% sodium carbonate treated bentonite clay. The composite lost its transparency normally encountered with the neat PMMA. The composite was characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), vicat softening point (VSP), dynamic mechanical thermal analysis (DMTA), and tensile studies. The morphology was investigated by scanning electron microscopy (SEM) and atomic forced microscopy (AFM) as well. The crystallography was studied to estimate the changes in crystallographic planes by X‐ray diffraction (XRD) analysis. The particle size distribution was compared amongst neat bentonite clay, neat PMMA and the composite. The FTIR spectra reveal the fact that no new primary valence bond is formed between the clay and PMMA. The thermal stability of the composite is significantly improved, as indicated by the TGA and VSP studies. A substantial increase in glass transition temperature (Tg) approximately, 10°C was recorded from the DMTA as both the storage modulus and tan δ values underwent inflexion at higher temperatures in case of the composite compared with the pristine PMMA. The XRD pattern indicates increase in basal “d” spacing for the composite. The morphology from both the SEM and AFM is quite supportive to well‐dispersed exfoliation. The incorporation of nanosized activated clay particles in PMMA during its in situ polymerization from MMA led to the formation of nanocomposites. POLYM. COMPOS., 2013. © 2012 Society of Plastics Engineers  相似文献   

8.
Poly(o‐anisidine)/V2O5 and poly(o‐anthranilic acid)/V2O5 nanocomposites were prepared by in situ intercalative polymerization, and the structure and electrical properties of these nanocomposites were investigated using GPC, TGA, XRD, TEM, FTIR, UV‐vis as well as conductivity measurement. The results show that the steric effect and nature of the substituting groups in the aromatic ring has an influence on the structure and electrical properties of the nanocomposites. Poly(o‐anisidine) or poly(o‐anthranilic acid) exists as a monolayer of outstretched chains in the gallery of the V2O5 xerogel owing to the confined environment in the nanometer‐size gallery. And intercalation of poly(o‐anisidine) or poly(o‐anthranilic acid) can improve the conductivity of V2O5 xerogel. Copyright © 2005 Society of Chemical Industry  相似文献   

9.
High‐density polyethylene (HDPE)/hydrotalcite nanocomposites were prepared and characterized with a partially neutralized sodium ionomer of poly(ethylene‐co‐methacrylic acid) (EMAA) as a compatibilizer. Moreover, nanocomposites based on this ionomer were characterized as patterns to analyze the interactions between the hydrotalcite sheets and the methacrylic groups on the ionomer. Hydrotalcite particles were organically modified with sodium dodecyl sulfate ions. Their presence in the interlayer space was confirmed by means of Fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD). Morphological analysis carried out with XRD and transmission electron microscopy (TEM) revealed the partially exfoliated/intercalated structure achieved in the nanocomposites. The mechanical properties of the HDPE nanocomposites mainly depended on the nature of the polymer matrix. Higher values of the tensile strength and Young's modulus were found in the EMAA nanocomposites. Thermogravimetric analysis (TGA) showed that hydrotalcite particles improved the thermal stability and delayed the onset decomposition temperature of both HDPE and EMAA nanocomposites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

10.
A novel temperature responsive copolymer, poly[2‐(2‐methoxyethoxy)ethyl methacrylate‐co‐oligo(ethylene glycol)methacrylate‐co‐N‐hydroxymethyl acrylamide] [P(MEO2MA‐co‐OEGMA‐co‐HMAM)], was synthesized by atom transfer radical polymerization. pH responsive poly(methacrylic acid) (PMAA) was synthesized by reversible addition‐fragmentation chain transfer polymerization. After the hydroxyl groups on P(MEO2MA‐co‐OEGMA‐co‐HMAM) were transformed into azide groups and the carboxyl groups on PMAA were transformed into alkyne groups respectively, a novel temperature and pH responsive hydrogel was fabricated by click chemistry between the azide‐P(MEO2MA‐co‐OEGMA‐co‐HMAM) and alkyne‐PMAA in the presence of CuSO4 and sodium ascorbate in aqueous solution. The rheological kinetics of gel formation demonstrated that gelation had commenced within 5 min at 25 °C, since then the storage modulus (G′) was higher than the loss modulus (G″). SEM images of hydrogel morphology and the swelling ratios of hydrogel at different temperatures and pH proved that the formed hydrogel had temperature and pH sensitivities. Bovine serum albumin was used as a model to evaluate the sustained release of the hydrogel; the results indicated that the hydrogel was a promising candidate for controlling protein drug delivery. © 2015 Society of Chemical Industry  相似文献   

11.
Polyaniline functionalized reduced graphene oxide (PORGO) is prepared by interfacial polymerization and then vertically oriented polyaniline‐graphene (PANI‐PORGO) nanocomposites based on PORGO are developed successfully by in situ polymerization. The morphology and structure are characterized by field emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FT‐IR), Raman spectra and X‐ray diffraction (XRD). The electrochemical tests indicate that the specific capacitance of PORGO and PANI‐PORGO is as high as 291 and 369 F/g, respectively, at the current density of 1 A/g. PANI—PORGO nanocomposite exhibits high electrochemical activity and enhanced cycle stability with a capacitance retention of 81.2% after 500 cycles at 10 A/g. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44808.  相似文献   

12.
Nanotechnology has emerged as a subject of immense academic interest and excitement in the past few decades. The immediate goal of this science aims at the production of high performance nanomaterials. The present study reports comparative investigations on the in situ polymerization of polyaniline (PANI), and its derivatives poly(1‐naphthylamine) (PNA) and poly(o‐toluidine) (POT) within the camphor sulphonic acid (CSA) modified montmorillonite (MMT) layers. The polymerization as well as intercalation of the conducting polymers was confirmed by FT‐IR, UV‐visible spectroscopies, and XRD studies, whereas the morphology of the nanocomposites was analyzed by TEM studies. It was found that the PANI derivatives (PNA and POT) revealed higher intercalation as compared with PANI. The morphology of nanocomposites was found to be governed by the type of conducting polymer intercalated. A large variation in the morphology as well as particle size was observed between the nanocomposites of PANI and its derivatives. The conductivity was found to be in the range of 10−3–10−2 S·cm−1. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers  相似文献   

13.
Polyaniline/graphene (PANI/GN) nanocomposites were fabricated via in‐situ oxidative polymerization of aniline in the presence of cetyltrimethylammonium bromide (CTAB) modified graphene (CGN) in 1M hydrochloric acid (HCl) solution. The morphology and structure of PANI/GN samples were investigated by Fourier transform infrared spectrum, X‐ray diffraction, ultraviolet and visible spectrum, thermogravimetric analysis, field‐emission scanning microscope (FE‐SEM), and transmitting electron microscopy (TEM). The conductivities of the PANI/GN nanocomposites were measured using four‐probe electrical conductivity measurement. The results indicated that the GN sheets disperse into the form of monolayer or stack few layers in PANI matrix. The GN sheets serve as a support material for PANI particles and the structure of GN covered with PANI nanoparticles were confirmed by FE‐SEM and TEM. The electrical conductivities of the PANI/GN samples have been improved compared with pure PANI prepared in the similar condition. POLYM. COMPOS., 36:1767–1774, 2015. © 2014 Society of Plastics Engineers  相似文献   

14.
A simple method was used to synthesize poly(2-aminophenol), poly(2-aminophenol-co-Aniline) and polyaniline nanocomposites with sodium-montmorillonite (Na-M) using in situ intercalative oxidative polymerization. Morphology and thermal properties of the synthesized nanocomposites were examined by transmission electron microscopy (TEM) and thermogravimetric analysis. The thermal analysis shows an improved thermal stability of the nanocomposites in comparison with the pure poly(2-aminophenol). The intercalation of polymers into the clay layers was confirmed by X-ray diffraction studies, TEM images and FTIR spectroscopy. In addition, the room temperature conductivity values of these nanocomposites varied between 8.21 × 10?5 and 6.76 × 10?4 S cm?1. The electrochemical behavior of the polymers extracted from the nanocomposites, has been analyzed by cyclic voltammetry. Good electrochemical response has been observed for polymer films; the observed redox processes indicate that the polymerization into Na-M produces electroactive polymers.  相似文献   

15.
Temperature and pH responsive poly(N‐isopropylacrylamide‐co‐methacrylic acid) (P(NIPAAm‐co‐MAA)) microcontainers with encapsulated magnetic nanoparticles in the shell were prepared by a two‐stage distillation precipitation polymerization. PMAA@Fe3O4/P(NIPAAm‐co‐MAA) core–shell nanoparticles were synthesized by the second‐stage polymerization of NIPAAm, MAA and N, N′‐methylenebisacrylamide as crosslinker in the presence of magnetic nanoparticles and PMAA as core. These novel triple‐functional microcontainers were prepared by selective removal of the PMAA core in water. Daunorubicin hydrochloride (DNR) was loaded into the microcontainers and the release profile was studied by UV–visible spectroscopy. The synthesized nanostructures were characterized with transmission and scanning electron microscopy, X‐ray diffraction and Fourier transform infrared spectroscopy. The magnetic properties were evaluated by vibrating sample magnetometry. The shrink and swelling behavior was studied by dynamic light scattering. Copyright © 2012 Society of Chemical Industry  相似文献   

16.
Poly(N‐methylpyrrole) (PNMPy), poly(N‐methylpyrrole‐TiO2) (PNMPy‐TiO2), and poly (N‐methylpyrrole‐ZnO) (PNMPy‐ZnO) nanocomposites were synthesized by in situ electropolymerization for cathode active material of lithium secondary batteries. The charge–discharging behavior of a Li/LiClO4/PNMPy battery was studied and compared with Li/LiClO4/PNMPy‐nanocomposite batteries. The nanocomposites and PNMPy films were characterized by cyclic voltammetry, in situ resistivity measurements, in situ UV–visible, and Fourier transform infra‐red (FTIR) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The differences between redox couples (ΔE) were obtained for polymer nanocomposites and PNMPy films. During redox scan, a negative shift of potential was observed for polymer nanocomposite films. Significant differences from in situ resistivity of nanocomposites and PNMPy films were obtained. The in situ UV–visible spectra for PNMPy and polymer nanocomposite films show the intermediate spectroscopic behavior between polymer nanocomposites and PNMPy films. The FTIR peaks of polymer nanocomposite films were found to shift to higher wavelengths in PNMPy films. The SEM and TEM micrographs of nanocomposite films show the presence of nanoparticle in PNMPy backbone clearly. The result suggests that the inorganic semiconductor particles were incorporated in organic conducting PNMPy, which consequently modifies the properties and morphology of the film significantly. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41526.  相似文献   

17.
The enzyme‐catalyzed synthesis of poly(p‐ethylphenol) (PEP) was modified by copolymerization with polycarbonates through triphosgene at low temperature to form polycarbonate‐co‐poly(p‐ethylphenol) (PC‐co‐PEP). FTIR, NMR, GPC, and thermal analysis verified the formation of PC‐co‐PEP. The copolymers have an optical absorption in the UV range. CdS semiconductor nanocrystallites were synthesized in reversed micelles with subsequent in situ enzymatic copolymerization of p‐ethylphenol and 4‐hydroxythiophenol in the same medium. TEM and ATR–FTIR showed that the polymer precipitated in spherical morphologies, incorporating CdS nanocrystals into the polymer matrix, with surface hydroxyl groups. The polymer/CdS core was then dispersed into polycarbonate. The polymer/CdS nanocomposites showed higher optical aborbance in the UV‐vis range when compared to the polymer matrix without CdS. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1851–1868, 1999  相似文献   

18.
Poly(styrene‐co‐methacrylic acid) containing 29 mol % of methacrylic acid (SMA‐29) and poly(isobutyl methacrylate‐co‐4‐vinylpyridine) containing 20 mol % of 4‐vinylpyridine (IBM4VP‐20) were synthesized, characterized, and used to elaborate binary and ternary nanocomposites of different ratios with a 3% by weight hexadecylammonium‐modified bentonite from Maghnia (Algeria) by casting method from tetrahydrofuran (THF) solutions. The morphology and the thermal behavior of these binary and ternary elaborated nanocomposites were investigated by X‐ray diffraction, scanning electron microscopy, FTIR spectroscopy, differential scanning calorimetry, and thermogravimetry. Polymer nanocomposites and nanoblends of different morphologies were obtained. The effect of the organoclay and its dispersion within the blend matrix on the phase behavior of the miscible SMA29/IBM4VP20 blends is discussed. The obtained results showed that increasing the amount of SMA29 in the IBM4VP20/SMA29 blend leads to near exfoliated nanostructure with significantly improved thermal stability. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

19.
A new inverse emulsion polymerization and intercalation procedure in supercritical carbon dioxide (SCCO2) was initially employed to synthesize polyaniline‐montmorillonite (PANI‐MMT) nanocomposites. The effect of chemical groups in MMT galleries on intercalation in SCCO2 was investigated. The MMTs modified by different organic cationic surfactants were incorporated into the composite particles, and in unintercalated, partially delaminated or fully exfoliated state. The aminated MMT or fluorinated MMT were utilized to prepare conducting PANI‐MMT nanocomposites with highly concentrated (12–25 wt% loading to monomer), fully exfoliated MMT platelets in SCCO2. The structure and morphology of PANI‐MMT nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X‐ray powder diffraction pattern (XRD), and transmission electron microscope (TEM). Thermogravimetry analysis (TGA) was performed to demonstrate the enhancement of thermal stability of the composites. SCCO2 was shown to be more effective for impregnation, disaggregation and exfoliation of MMTs than isooctane, which indicates that SCCO2 is an alternative solvent for synthesis of some intercalated composite materials, not only based on the environmental friendly characteristic of SCCO2, but also owing to that SCCO2 can play an important role in intercalative polymerization. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers  相似文献   

20.
Xiaoying Yang  Liting Chen  Feng Bai 《Polymer》2009,50(15):3556-153
The pH-sensitive hollow poly(N,N′-methylene bisacrylamide-co-methacrylic acid) (P(MBAAm-co-MAA)) microspheres were prepared by a two-stage distillation precipitation polymerization to afford a core-shell poly(methacrylic acid)/poly(N,N′-methylene bisacrylamide-co-methacrylic acid) (PMAA/(P(MBAAm-co-MAA))) microsphere with subsequent removal of poly(methacrylic acid) (PMAA) core. PMAA/P(MBAAm-co-MAA) core-shell microspheres were synthesized by the second-stage copolymerization of N,N′-methylene bisacrylamide (MBAAm) as crosslinker and the functional methacrylic acid (MAA) comonomer in acetonitrile with 2,2′-azobisisobutyronitrile (AIBN) as initiator. The pH-responsive properties of hollow P(MBAAm-co-MAA) microspheres were investigated by dynamic laser scattering (DLS). The loading and controlled-release behavior of the drug for hollow P(MBAAm-co-MAA) microspheres was strongly dependent on the pH values with doxorubicin hydrochloride (DXR) as a model molecule. The core-shell and hollow polymer microspheres were characterized by transmission electron microscopy (TEM), Fourier-transform infrared spectra (FT-IR), DLS and elemental analysis.  相似文献   

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