• Polymer(Korea)
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• v.27 no.6
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• pp.549-554
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• 2003

Emeraldine salt of polyaniline-dodecylbenzenesulfdnic acid (PANI-DBSA) in organic solvents such as toluene and xylene was obtained by a direct one-step emulsion polymerization technique. When the molar ratio of DBSA to aniline monomer was 1.5:1, its solubility and electric property showed a maximum value and then the solid contents of PANI-DBSA was 8 wt% in toluene. The cast film of PANI-DBSA with no binder was obtained on glass or plastic substrates under ambient conditions. PANI solution can be also easily blended with polyurethane and polystyrene polymers in toluene. Improved electrical performance up to 5 S/cm was achieved with good light-transmittance up to 70% at 500 m thickness. They also showed more homogeneous morphology than that prepared with PANI-DBSA kom aqueous dispersion polymerization. The partially dispersed PANI-DBSA showed particles sizes of 50-400 m in organic solvents and their XRD pattern were observed from the powder sample.

• Journal of Adhesion and Interface
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• v.3 no.4
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• pp.27-36
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• 2002

The organic/organic core-shell composite polymer for nonwomen binder were synthesized by stage polymerization of methyl methacrylate and styrene with ammonium persulfate after preparing monomer pre-emulsion in the presence of anionic surfactant. We study the effect of initiator concentration, $0.79{\times}10^{-3}{\sim}3.16{\times}10^{-3}mol/L$ for core polymer, $2.0{\times}10^{-4}{\sim}8.0{\times}10^{-4}mol/L$ for shell polymer, sulfactant concentration, $1.45{\times}10^{-5}{\sim}4.15{\times}10^{-5}mol/L$ for core polymer, $0.73{\times}10^{-5}{\sim}2.91{\times}10^{-5}mol/L$ for shell polymer on core-shell structure of polymethyl methacrylate/polystyrene and polystyrene/polymethyl methacrylate. Emulsion stability was major test method, particle size and particle size distribution were measured using particle size analyzer and the morphology of the core-shell composite polymer was determined using transmission electron microscope, glass temperature was also measured using differential scanning calorimeter.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1633-1637
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• 2006

We demonstrate a selective vapor-phase deposition of conductive poly(3,4-ethylenedioxythiophene) (PEDOT) thin films on patterned $FeCl_3$. The PEDOT thin films were grown on various substrates by using the vapor-phase polymerization of ethylenedioxythiophene (EDOT) with $FeCl_3$ catalytic layers at 325 K. The selective deposition of the PEDOT thin films using vapor-phase polymerization was accomplished with patterned $FeCl_3$ layers as templates. Microcontact printing was done to prepare patterned $FeCl_3$ on polyethyleneterephthalate (PET) substrates. The selective vapor-phase deposition is based on the fact that the PEDOT thin films are selectively deposited only on the regions exposing $FeCl_3$ of the PET substrates, because the EDOT monomer can be polymerized only in the presence of oxidants, such as $FeCl_3$, Fe($CIO_4$), and iron(II) salts of organic acids/inorganic acids containing organic radicals.

• Journal of the Korean Ceramic Society
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• v.33 no.12
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• pp.1365-1372
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• 1996

In order to obtain a transparent and dimer-free Ormosil embedded with orgainc dye variations of gel struc-ture and optical properties were studied as a functiion of the change of gel composition. The Ormosils which have good optical property were produced in the 90/10 ratio of TEOS/PDMS and the structural variations of the gel were achived by the change of ratio of HCl/TEOS. As the ratio of HCl/TEOS was increased pore size of the Ormosil enlarged and porosity increased. Increasing HCl concentration led to gradually lower trans-mittance values. In the xerogel doped with the organic dye Rhodamine 6G perchlorate a dimer peak near 500nm was observed with the increase of the ratio of HCl/TEOS

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.7
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• pp.615-620
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• 2002

In the case of immobilizing of glucose oxidase into polypyrrole (PPy) using electrosynthesis, the glucose oxidise (GOx) forms a coordinate bond with the polymers backbone. However, because of intrinsic insulation and net-chain of the enzyme, the charge transfer and mass transport are obstructed during the film growth. Therefore, the film growth is dull. We synthesized enzyme electrodes by electropolymerization added some organic solvent, such as ethanol and tetrahydrofuran (THF). The formative seeds of film growth was delayed by adding ethanol. The delay was induced by radical transfer between ethanol and pyrrole monomer. The radical transfer reactions shared the contribution of dopants between electrolyte anion and GOx polyanion. This led to increase amount of immobilized the enzyme in PPy. For the UV absorption spectra of synthetic solution before synthesis and after, in the case of ethanol added, the optical density was slightly decreased for the GOx peaks. It suggests amount of GOx in the solution was decreased and amount of GOx in the film was increased.

• Macromolecular Research
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• v.15 no.7
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• pp.633-639
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• 2007

A variety of NMR techniques were applied to the micro-chemical structural characterization of polyanilines prepared via an efficient synthetic method in a self-stabilized dispersion medium in which the polymerization was conducted in a heterogeneous organic/aqueous biphasic system without any stabilizers. Here, the monomer and growing polymer chain were shown to function simultaneously as a stabilizer, imparting compatibility for the dispersion of the organic phase, and as a form of flexible template in an aqueous reaction medium. Polymerizations predicated on this concept generated polyanilines with a low defect content: solution state $^{13}C-NMR$ and solid $^{13}CDD/CP/MAS$ spectroscopy indicated that the synthesized HCPANi and its soluble derivative, HCPANi-t-BOC, evidenced distinctly different NMR spectra with fewer side peaks, as compared to conventionally prepared PANis, and the complete structural assignments of the observed NMR peaks could be determined via the combination of both 1D and 2D techniques. Ortho-linked defects in HCPANi were estimated to be as low as 7%, as shown by a comparison of the integration of the carbonyl carbon resonance peaks.

• The Journal of Engineering Research
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• v.7 no.1
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• pp.79-87
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• 2005

[TEACOOH]-Montmorillonite intercalations complex obtained from Na-Montmorillonite and 10-Carboxy-n-decyldimethylethylammonium bromide(organic cation) was reacted with the monomer($\varepsilon$-caprolactone) to achieve the [TEACOOH]-$\varepsilon$-caprolactone-Montmorillonite intercalations complex. From intercalations complex Montmorillonite/Polycaprolactone Nanocomposite in which montmorillonite(inorganic material) is chemically linked with the polycaprolactone(organic polymer) was formed at $220^{\circ}C$ for 48 h. The basal spacing for the sample obtained after polymerization, extraction with methanol and dried at $65^{\circ}C$ in high vacuum for 24 h was 50.7 $\AA$.

• Journal of the Korean Applied Science and Technology
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• v.26 no.1
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• pp.74-79
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• 2009

The inorganic-organic composite particles with core-shell structure were polymerized by using styrene and potassium persulfate (KPS) as a shell monomer and an initiator, respectively. We studied the effect of surfactants on the core-shell structure of silicone dioxide/styrene composite particles polymerized in the presence of sodium dodecyl sulfate(SDS), polyoxyethylene alkylether sulfate (EU-S133D), and at none surfactant condition. We found that $SiO_2$ core / polystyrene(PS) shell structure was formed when polymerization of styrene was conducted on the surface of $SiO_2$ particles, and the concentration SDS and EU-Sl33D was $8.34{\times}10^{-2}mole/L$. The core-shell structure was confirmed by measuring the thermal decomposition of the polymer composite using thermogravimetric analyzer (TGA), and the morphology of the composite particles was characterized by transmission electron microscope (TEM).

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.351-354
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• 2000

1.3-Propanediol as a bifunctional organic compound could potentially be used for many synthesis reactions, in particular as a monomer for polycondensations to produce polyesters, polyethers and polyurethanes. Wastewater containing high concentration of glycerol was used to produce 1,3-propanediol in lower production cost which inturn the quantity of wastewater to be treated. In this study, various attempts were made to increase 1,3-propanediol production under different conditions by Klebsiella pneumoniae ATCC 15380. 1,3-Propanedio conversion yield and by-product formation were influenced significantly by pH and temperature. The Optimal glycerol and nitrogen concentration for 1,3-propanediol production were found to be 25g/L and 1%(w/v), respectively. The production formation of 1,3-propanediol was optimal at pH 6.0 and temperature $35^{\circ}C$.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.133-133
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• 2003

가스센서는 인간의 오감 중에 후각 기능을 대신하는 것으로 사회 여러 분야에 응용범위가 확대되고 있다. 유기화합물(VOC; volatile organic compounds) 가스는 대기환경을 오염시켜 스모그를 발생하며 인체에 발암을 유발하는 물질이기 때문에 많은 문제와 규제가 예상되고 있다. 따라서 VOC를 감지하고 정확히 분석할 수 있는 환경 측정용 센서에 대한 요구가 절실해지고 있다. 최근에는 고온에서 동작하는 산화물 반도체 센서와는 달리 상온에서 유해성 가스를 감지할 수 있는 전도성 고분자의 특성이 알려지면서 센서 물질로 각광을 받고 있으며, 특히 유해성 가스인 VOC 가스를 검지 할 수 있는 센서로서 주목을 받고 있다. 전도성 고분자인 Polypyrrole를 pyrrole monomer, APS, DBSA를 사용하여 $0^{\circ}C$, 1기압에서 화학중합을 하였다. 만들어진 powder를 chloroform과 DBSA를 사용하여 용액을 만들어 전극에 dipping하고 7$0^{\circ}C$, 질소 분위기에서 1시간동안 건조를 하고 methanol에서 1시간동안 soaking 처리를 한 뒤 7$0^{\circ}C$, 질소 분위기에서 4시간동안 열처리 과정을 통해 센서를 제조하였다.