Synthesis of MWCNTs-core/thiophene polymer-sheath composite nanocables by a cationic surfactant-assisted chemical oxidative polymerization and their structural properties

Reddy, Kakarla Raghava,Jeong, Han Mo,Lee, Youngil,Raghu, Anjanapura Venkataramanaiah Wiley Subscription Services, Inc., A Wiley Company 2010 Journal of polymer science Part A, Polymer chemist Vol.48 No.7

<P>Multi-walled carbon nanotubes (MWCNTs)-core/thiophene polymer-sheath composite nanocables were synthesized by chemical oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) with oxidant (FeCl<SUB>3</SUB>) in the presence of cationic surfactant, deceyltrimethyl ammonium bromide (DTAB). In the polymerization process, DTAB surfactant molecules were adsorbed on the surface of MWCNTs and forms MWCNTs-DTAB soft template. Upon the addition of EDOT and oxidant, the polymerization take place on the surface of MWCNTs and PEDOT is gradually deposited on the surface of MWCNTs. The resulting MWCNTs-PEDOT nanocomposites have the nanocable structure. Nanocomposites were characterized by HRTEM, FE-SEM, XRD, XPS, TGA, FTIR and PL, respectively. The π-π interactions between PEDOT and MWCNTs enhancing the thermal and electrical properties of the nanocomposites with loading of MWCNTs. The temperature dependence conductivity measurements show that the conductivity of the nanocomposite decrease with a decrease of temperature, and conductivity-temperature relationship is well fit by the quasi-one dimensional variable range hopping mode. The mechanism for the formation of composite nanocables was explained on the basis of self- assembly of micelles. The reported self-assembly strategy for the synthesis of PEDOT-coated MWCNTs in micellar medium is a rapid, versatile, potentially scalable, stable, and making it useful for further exploitation in a varies types of applications. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1477–1484, 2010</P> <B>Graphic Abstract</B> <P>The MWCNTs-thiophene polymer core-sheath composite nanocables were synthesized by chemical oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) with oxidant (FeCl<SUB>3</SUB>) in the presence of cationic surfactant, deceyltrimethyl ammonium bromide (DTAB) that acts as the structure-directing agen. In the polymerization process, DTAB surfactant molecules were adsorbed on the surface of MWCNTs and forms MWCNTs-DTAB soft template. On the addition of EDOT and oxidant, the polymerization takes place on the surface of MWCNTs, and PEDOT is gradually deposited on the surface of MWCNTs. The resulting nanocomposites have the nanocable structure as shown in the scheme. The structural, morphological, thermal, optical, and electrical properties of the synthesized nanocomposites were fully characterized by using various techniques. The mechanism for the formation of composite nanocables was explained on the basis of self-assembly of micelles. The reported self-assembly strategy for the synthesis of PEDOT-coated MWCNTs in micellar medium is a rapid, versatile, potentially scalable, stable, and making it useful for further exploitation in various types of applications. <img src='wiley_img_2010/0887624X-2010-48-7-POLA23883-gra001.gif' alt='wiley_img_2010/0887624X-2010-48-7-POLA23883-gra001'> </P>

Synthesis of semiconducting poly(diphenylamine) particles and analysis of their electrorheological properties

Kim, Min Hwan,Bae, Dong Hun,Choi, Hyoung Jin,Seo, Yongsok Elsevier 2017 Polymer Vol.119 No.-

<P><B>Abstract</B></P> <P>Poly(diphenylamine) (PDPA) particles were synthesized as a novel semiconducting electro-responsive electrorheological (ER) material by a chemical oxidative polymerization process and their ER characteristics were investigated at various electric fields. Surface morphology of these <I>N</I>-aryl-substituted polyaniline-derived PDPA particles was examined by scanning electron microscopy and their chemical structure and thermal properties were confirmed by Fourier-transform infrared spectroscopy and thermogravimetric analysis, respectively. Their susceptibility to electric fields and the chain formation of dispersed particles were observed directly using optical microscopy. Rheological analysis of the PDPA-based ER fluid was performed using a combination of steady shear and oscillation tests in a Couette-type rotational rheometer with a high-voltage power supply. The measurements were performed in controlled shear stress and shear rate modes under the varied electric field strengths. The Cho–Choi–Jhon model was found to determine the stress behavior more clearly. Dielectric analysis provided additional information about the electrical polarization properties and thus also the ER performance of the PDPA-based ER fluid.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Semiconducting poly(diphenylamine) (PDPA) particles were synthesized by chemical oxidation. </LI> <LI> PDPA particles show typical electrorheological (ER) property examined using a rotational rheometer. </LI> <LI> PDPA particles are directly applied into ER fluid without dedoping process. </LI> <LI> Dielectric analysis was proceeded to confirm electrical polarization of PDPA particles. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Photocatalytic degradation of malachite green dye using zero valent iron doped polypyrrole

Bircan HASPULAT TAYMAZ,Handan KAMI?,Ozge YOLDA? 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.2

The zero valent iron doped polypyrrole (Ppy/Fe) was synthesized via chemical oxidative polymerization method in diethylene glycol medium for the first time in this study. The characterization of synthesized Ppy and Ppy/Fe composites was realized by using fourier transform infrared spectrometer (FTIR), UV-visible diffuse reflectance spectrometer (DRS), scanning electron microscope (SEM), elemental dispersion X-ray analysis (EDX), four point probe electrical conductivity X-Ray diffraction spectroscopy (XRD) and pH at point of zero charge (pHpzc) methods. These characterizations show that there is an interaction between zero valent iron (Fe<SUP>0</SUP>) and Ppy polymer. The photocatalytic activity of synthesized Ppy and Ppy/Fe composite were investigated by degradation of malachite green (MG) dye under UV light irradiation. Ppy/Fe composite was achieved complete degradation within 60 min, which is 5.92 times faster than pure Ppy. The effect of irradiation time, ratio of Ppy and Fe<SUP>0</SUP> in the synthesized composites, photocatalyst amount to photocatalytic efficiency of Ppy/Fe is studied. Also, the photocatalytic stability of Ppy/Fe is investigated under UV light illumination for degradation MG dye.

One-Step Preparation of Antimicrobial Polyrhodanine Nanotubes with Silver Nanoparticles

Kong, Hyeyoung,Song, Jooyoung,Jang, Jyongsik WILEY-VCH Verlag 2009 Macromolecular Rapid Communications Vol.30 No.15

<P>A simple synthetic method has been developed for the fabrication of antimicrobial polyrhodanine nanotubes with silver nanoparticles. Rhodanine monomer first forms one-dimensional complexes with silver ions due to coordinative interactions and consecutively reduces the silver ions during chemical-oxidation polymerization. The polymerization procedure is analyzed by transmission electron microscopy and scanning electron microscopy in situ. The synthesized silver nanoparticles/polyrhodanine nanotubes are applied as an antimicrobial agent against Gram-negative bacteria, E. coli and Gram-positive bacteria, S. aureus. The antimicrobial tests demonstrate that the silver/polyrhodanine nanotubes have superior antimicrobial properties to silver nanoparticles and rhodanine monomer.</P><P> <img src='wiley_img/10221336-2009-30-15-MARC200900106-gra001.gif' alt='wiley_img/10221336-2009-30-15-MARC200900106-gra001'> </P> <B>Graphic Abstract</B> <P>Polyrhodanine nanotubes with silver nanoparticles were fabricated using a template-free, one-step chemical-oxidation polymerization with the aid of ethyl alcohol solvent. Antibacterial tests revealed that the synthesized silver/polyrhodanine nanotubes had an excellent antimicrobial potency against Gram-negative bacteria, E. coli and Gram-positive bacteria, S. aureus. <img src='wiley_img/10221336-2009-30-15-MARC200900106-content.gif' alt='wiley_img/10221336-2009-30-15-MARC200900106-content'> </P>

고분자 전해질 막의 화학적 내구성 향상을 위한 고분자형 산화방지제 제조 및 특성 분석

이별님,Abdul Kodir,이혜진,신동원,배병찬 한국수소및신에너지학회 2021 한국수소 및 신에너지학회논문집 Vol.32 No.5

Chemical durability issue in polymer electrolyte membranes has been a challenge for the commercialization of polymer electrolyte membrane fuel cells (PEMFCs). In this study, we proposed a manufacturing method of Nafion composite membrane containing a stable polyimide antioxidant to improve the chemical durability of the membrane. The thermal casting of the Nafion solution with poly (amic acid) induced polyimide reaction. We evaluated proton conductivity, oxidative stability with ex-situ Fenton's test, and fluoride ion emission to analyze the effect of polyimide antioxidants. We confirmed that incorporating the polyimide antioxidant improves the chemical durability of the Nafion membrane while maintaining inherent proton conductivity.

그래핀 옥사이드와 폴리피롤로 개질된 우레탄 폼의 전극 지지체 및 화학 센서로 하이브리드 이중 기능화 연구

조현진,노영주,진은영,임진형 한국고분자학회 2023 폴리머 Vol.47 No.4

In this study, three kinds of flexible and electrically conductive polyurethane foam (PUF) composites (PUF-GO, PUF-PPy, PUF-PPy-GO) were prepared using vapor phase polymerization of pyrrole and the impregnation of graphene oxide (GO) processes. It was confirmed that control of the electro-mechanical properties of the composite by changing the shape of the conductive layer was formed differently depending on the manufacturing process of the conductive PUF composites. The prepared PUF composites were evaluated for hybrid dual-functional applications (chemical sensors and supercapacitance electrode supports) to investigate potentials for various application fields. PUF-PPy-GO composite shows good performance as a chemical sensor, showing the best ammonia gas sensing characteristics and excellent selectivity for other electron-donating chemical gases. It is believed that this is because the electrically conductive layer composed of PPy and GO is uniformly formed on the inner surface of the porous composite. In addition, as a result of application as an electrode support for supercapacitors, the specific area capacitance (22.2 mFcm-2) of PUF-PPy-GO was the highest, which was about 10 times higher than that of the PUF-GO composite (2.5 mFcm-2). It is considered that the PUF-PPy-GO composite would provide a facile path for smooth exchange with electrolyte ions during the charging·discharging process.

Improving oxidation stability of 2D MXenes: synthesis, storage media, and conditions

IQBAL AAMIR,Hong Junpyo,고태윤,구종민 나노기술연구협의회 2021 Nano Convergence Vol.8 No.9

Understanding and preventing oxidative degradation of MXene suspensions is essential for fostering fundamental academic studies and facilitating widespread industrial applications. Owing to their outstanding electrical, electrochemical, optoelectronic, and mechanical properties, MXenes, an emerging class of two-dimensional (2D) nanomaterials, show promising state-of-the-art performances in various applications including electromagnetic interference (EMI) shielding, terahertz shielding, electrochemical energy storage, triboelectric nanogenerators, thermal heaters, light-emitting diodes (LEDs), optoelectronics, and sensors. However, MXene synthesis using harsh chemical etching causes many defects or vacancies on the surface of the synthesized MXene flakes. Defective sites are vulnerable to oxidative degradation reactions with water and/or oxygen, which deteriorate the intrinsic properties of MXenes. In this review, we demonstrate the nature of oxidative degradation of MXenes and highlight the recent advancements in controlling the oxidation kinetics of MXenes with several promising strategic approaches, including careful control of the quality of the parent MAX phase, chemical etching conditions, defect passivation, dispersion medium, storage conditions, and polymer composites.

Localized Temperature and Chemical Reaction Control in Nanoscale Space by Nanowire Array

Jin, C. Yan,Li, Zhiyong,Williams, R. Stanley,Lee, K.-Cheol,Park, Inkyu American Chemical Society 2011 Nano letters Vol.11 No.11

<P>We introduce a novel method for chemical reaction control with nanoscale spatial resolution based on localized heating by using a well-aligned nanowire array. Numerical and experimental analysis shows that each individual nanowire could be selectively and rapidly Joule heated for local and ultrafast temperature modulation in nanoscale space (e.g., maximum temperature gradient 2.2 K/nm at the nanowire edge; heating/cooling time < 2 μs). By taking advantage of this capability, several nanoscale chemical reactions such as polymer decomposition/cross-linking and direct and localized hydrothermal synthesis of metal oxide nanowires were demonstrated.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2011/nalefd.2011.11.issue-11/nl2026585/production/images/medium/nl-2011-026585_0005.gif'></P>

Preparation and characterization of prospective disulfide based electrode materials for lithium batteries

Ragupathy, Dhanusuraman,Gopalan, Anantha Iyengar,Lee, Kwang-Pill The Korean Society of Analytical Sciences 2008 분석과학 Vol.21 No.1

Organic disulfide compounds are having higher theoretical capacity than the conventional cathode material and are considered as the important storage material. Here, we are reporting the preparation of poly (2,2'-dithiodianiline) PDDA/multiwall carbon nanotubes, (MWCNTs) composites under different experimental conditions. Amine functionalized and unfunctionalized MWCNTs were independently used for the preparation of composites. Composites were prepared in the presence of cetyl trimethyl bromide (CTAB), a cationic surfactant, and also in the absence of CTAB. A physical mixture of PDTDA and MWCNTs was formed with unfunctionalized MWCNTs. Grafting of PDDA onto MWCNTs was performed by chemical oxidative polymerization of 2, 2'-dithiodianiline in the presence of amine functionalized MWCNTs. The composites of MWCNTs and PDTDA were characterized for structure, morphology and thermal properties through Fourier transform infrared spectroscopy, Fourier transform Raman spectroscopy, scanning electron microscopy and UV-visible spectroscopy. The composite materials prepared by this method are expected to find applications as electrode materials for lithium batteries.

Preparation and characterization of prospective disulfide based electrode materials ofr lithium batteries

Dhanusuraman Ragupathy,Anantha Iyengar,이광필 한국분석과학회 2008 분석과학 Vol.21 No.1

Organic disulfide compounds are having higher theoretical capacity than the conventional cathodematerial and are considered as the important storage material. Here, we are reporting the preparation of poly(2,2'-dithiodianiline) PDDA/multiwall carbon nanotubes, (MWCNTs) composites under different experimentalof composites. Composites were prepared in the presence of cetyl trimethyl bromide (CTAB), a cationicsurfactant, and also in the absence of CTAB. A physical mixture of PDTDA and MWCNTs was formed withunfunctionalized MWCNTs. Grafting of PDDA onto MWCNTs was performed by chemical oxidative polymerizationof 2, 2-dithiodianiline in the presence of amine functionalized MWCNTs. The composites of MWCNTs andPDTDA were characterized for structure, morphology anspectroscopy, Fourier transform Raman spectroscopy, scanning electron microscopy and UV-visible spectroscopy.The composite materials prepared by this method are expected to find applications as electrode materials forlithium batteries.