• Applied Chemistry for Engineering
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• v.35 no.4
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• pp.296-302
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• 2024

An ionic conjugated polymer-iron (III) chloride composite was prepared via in-situ quaternization polymerization of 2-ethynylpyridine (2EP) using iron (III) chloride. Various instrumental methods revealed that the chemical structure of the resulting conjugated polymer (P2EP)-iron (III) chloride composite has the conjugated backbone system having the designed pyridinium ferric chloride complexes. The polymerization mechanism was assumed to be that the activated triple bond of 2-ethynylpyridinium salt, formed at the first reaction step, is easily susceptible to the step-wise polymerization, followed by the same propagation step that contains the propagating macroanion and monomeric 2-ethynylpyridinium salts. The electro-optical and electrochemical properties of the P2EP-FeCl₃ composite were studied. In the UV-visible spectra of P2EP-FeCl₃ composite, the absorption maximum values were 480 nm and 533 nm, and the PL maximum value was 598 nm. The cyclic voltammograms of the P2EP-FeCl₃ composite exhibited irreversible electrochemical behavior between the oxidation and reduction peaks. The kinetics of the redox process of composites were found to be very close to a diffusion-controlled process from the plot of the oxidation current density versus the scan rate.

• Macromolecular Research
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• v.17 no.9
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• pp.714-717
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• 2009

Hole transport copolymers consisting of 3,4-ethylenedioxythiophene (EDOT) and N-4-butylphenyl-N,N-diphenylamine (BTPA) were synthesized by oxidative coupling reaction using $FeCl_3$ as an oxidant. These copolymers showed good solubility and their thin films showed sufficient morphological stability. The copolymers showed an absorption maximum around 320 nm. Copolymers had an oxidation peak at approximately $1.03{\sim}1.14V$ versus the Ag/AgCl electrode. The hole mobility increased with increasing portion of the EDOT unit. The hole mobility of the copolymer containing 57% of the EDOT unit showed the highest mobility of $3{\times}10^{-5}cm^2/V{\cdot}s$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.209-213
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• 2003

Polyaniline (PANi) composite particles were synthesized by chemical oxidation polymerization of aniline in presence of poly-n-isopropyl acryl amide (PNIPAM). The PANi particles formed in the reaction medium deposited onto non-conducting PNIPAM template to produce PANi-coated composite particles. The formation of composite was confirmed by FT-IR spectroscopy, and UV-VIS spectroscopy, and their morphological structures were examined by scanning electron microscopy (SEM). From the experimental results, it was determined that PANi was successfully coated onto non-conducting PNIPAM.

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.334-336
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• 2003

Polyaniline(PANi) composite panicles were synthesized by chemical oxidation polymerization of aniline in presence of Poly-N-Isopropyl acryl amide(PNIPAM). The PANi panicles are formed in the reaction medium deposited onto non-conducting PNIPAM template to produce PANi-coated composite panicles. The formation of composite was confirmed by FT-IR spectroscopy, and UV-VIS spectroscopy, and their morphological structures were examined by scanning electron microscopy(SEM). From the experimental results, it was determined that PANi was successfully coated onto non-conducting PANIPAM.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.432-437
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• 2013

The CO preferential oxidation reaction (PROX) has been done using Cu catalytic active species supported on some of mesoporous silica materials which can facilitate the diffusion of the reactants in order to prevent the poisoning of anode active materials by CO molecules during driving polymer electrolyte fuel cells (PEMFC) in this study. As a result when SBA-15 with large pore used as a support showed excellent CO oxidation activity, especially the activity increased in proportion to the amount of supported Cu. Ti components which was inserted to increase the degree of dispersion of Cu, contributed to improving the performance for CO oxidation at low-temperature. The degree of dispersion of Cu ingredients was the best in the catalyst inserted 20 mol-% Ti into the framework of SBA-15, and CO oxidation activity was also improved.

• Polymer(Korea)
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• v.39 no.2
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• pp.346-352
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• 2015

Polyalphaolefin (PAO) is a synthetic lubricant that is superior to mineral-based lubricants in the terms of physical and chemical characteristics such as low pour point, high viscosity index (VI), and thermal and oxidation stability. Several kinds of PAOs have been synthesized by using 1-pentene, 1-hexene, 1-octene, or 1-dodecene as monomer with three kinds of aluminum-based Lewis acid catalysts via cationic polymerization. The control of the catalytic performance and physical properties of PAO such like molecular weight, kinematic viscosity, pour point, and viscosity index was done by changing polymerization parameters. The alkyl aluminum halide-based catalysts show better catalytic activity than that of the conventional $AlCl_3$ catalyst. The microstructure of PAO was investigated by means of TOF-MS (time of flightmass spectroscopy) analysis in order to elucidate the correlation between the performances of the lubricant (VI, pour point) and the molecular structure of PAO. The VI of PAO increases with increases in the carbon number of ${\alpha}$-olefin. In other words, the performances of PAO as a lubricant strongly depended on the branch length of PAO.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1609-1612
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• 2003

The electrooxidation of 8-(3-acetylimino-6-methyl 2,4-dioxopyran)-1-aminonaphthaline (AMDAN) in aqueous and non aqueous media led to the formation of polymeric films, poly (AMDAN). The monomer, undergo anodic oxidation through the formation of a monocation radical irrespective of the nature of the medium. In aqueous medium, the monocation radical undergoes, through its resonance structures, dimerisation involving tail-to-tail, head-to-tail and even head-to-head coupling. The products formed, being more easily oxidisable than the parent substance, undergo further oxidation at the same potential so that the overall oxidation involves a one-step (i.e., a single wave), two-electron process. In non-aqueous medium, the monocation radical does not undergo dimerisation through coupling reactions. Retaining its identity, monomer oxidise in two steps involving one electron in each step. The fact that the cathodic peaks corresponding to these anodic peaks are rarely observed indicates fast consumption of the electrogenerated monocation radicals and dications by follow-up chemical reactions to produce polymeric products (poly AMDAN). The electrochemical behavior of the formed polymer films was investigated in both non aqueous and aqueous media. The films prepared in non aqueous medium were found to be more electroactive than that the films prepared in aqueous medium. This is confirmed with the results in litreature which illustrate that the film prepared in aqueous solution hold water in its structure via hydrogen bonding, which causes decomposition reactions.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2537-2543
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• 2011

A self-assembled Al-bridged diiminopyridine-based ligand (3) was synthesized and characterized by FT-IR, ESI-MS and NMR spectroscopy. Electron spectral titrations were performed to confirm the formation of a novel trinuclear bis(imino)pyridyl iron(II) complex (4) upon addition of $FeCl_2$ into Al-bridged ligand 3 in methanol solution. Simultaneously, a typical bis(imino)pyridine-iron(II) complex (2) was synthesized and fully characterized. The X-ray crystal study of the iron(II) complex 2 disclosed a five-coordinate, distorted square-pyramidal structure with the tridentate N^N^N ligand and chlorides. The optimal molecular structure of 4 was obtained by means of molecular mechanics, which showed that each iron atom in the complex 4 is surrounded by two chlorides, a tridentate N^N^N ligand and one oxygen atom, supporting considerations about the possibility of six-coordinate geometry from MMAO or the ethylene access. A comparison of 4 with the reference 2 revealed a remarkable decrease of the catalytic activity and MMAO consumption (activity up to $0.41{\times}10^3\;kg\;{mol_{Fe}}^{-1}h^{-1}bar^{-1}$, Al/Fe = 650 for 4 and $7.02{\times}10^3\;kg\;{mol_{Fe}}^{-1}h^{-1}bar^{-1}$, Al/Fe = 1600 for 2).

• Applied Chemistry for Engineering
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• v.29 no.3
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• pp.330-335
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• 2018

A new approach for the fabrication of organic-organic conducting composite thin films using simultaneous co-vaporization vapor phase polymerization (SC-VPP) of two or more monomers that have different polymerization mechanisms (i.e., oxidation-coupling polymerization and radical polymerization) was reported for the first time. In this study, a PEDOT-PSMA composite thin film consisting of poly(3,4-ethylenedioxythiophene)(PEDOT) and poly(styrene-co-maleic anhydride)(PSMA) was prepared by SC-VPP process. The preparation of organic-organic conductive composite thin films was confirmed through FT-IR and $^1H-NMR$ analyses. The surface morphology analysis showed that the surface of PEDOT-PSMA thin film was rougher than that of PEDOT thin film. Therefore, PEDOT-PSMA exhibited lower electrical conductivity than that of PEDOT. But the conductivity can be improved by adding 2-ethyl-4-methyl imidazole as a weak base. The contact angle of PEDOT-PSMA was about $50^{\circ}$, as compared to $62^{\circ}$ for PEDOT. The demonstrated methodology for preparing an organic-organic conductive hybrid thin film is expected to be useful for adjusting intrinsic conductive polymer (ICP)'s surface properties such as mechanical, optical, and roughness properties.

• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.450-454
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• 1973

The afterpolymerization and depolymerization of poly-${\varepsilon}$-caproamide in solid state have been studied under two different reaction conditions, nitrogen flow and sealed state. The degree of polymerization ($\bar{P}$) of nylon 6 increased with the increase in reaction time and temperature, and then reacted finally an equilibrium. In the presence of oxygen, $\bar{P}$ decreased by increasing the reaction time due to the oxidation reaction. Under certain reaction condition, the change of $\bar{P}$ for different initial degree of polymerization ($\bar{P}_0$) tendered toward unity in equilibrium.