• Title/Summary/Keyword: DBSA.

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Charge Transport Phenomena of Polyaniline-DBSA/Polystyrene Blends (폴리 아닐 린-DBSA/폴리스타이렌 블렌드의 전하 이동 현상)

  • 김원중;김태영;고정우;김윤상;박창모;서광석
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.6
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    • pp.305-311
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    • 2004
  • Charge transport phenomena of polyaniline-DBSA/High Impact Polystyrene (PAM-DBSA/HIPS) blends have been studied through an examination of electrical conduction. HIPS used host polymer in the blends and PANI-DBSA obey a space charge limited conduction mechanism and a ohmic conduction mechanism respectively. However, PANI-DBSA/HIPS blends do not obey any classical conduction mechanism. Analysis of conduction mechanism revealed that the charging current of PANI-DBSA/HIPS blends increased with the increase of PANI-DBSA content. This result migrlt be explained by the reduction in the distance between PANI-DBSA particles enabling the charge carriers to migrate from a chain to a neighboring chain via hopping or micro tunneling. It was also found that the charging current of PANI-DBSA/HIPS blends decreased as the temperature was elevated, which is of typical phenomena in metals. It is speculated that the charge transport in PANI-DBSA particle was somewhat constrained due to strong phonon scattering.

Effect of Dodecylbenzene Sulfonic Acid on the Behavior of Asphaltene Aggregation in a Solvent Deasphalting System

  • Liu, Lingyu;Go, Kang Seok;Nho, Nam Sun;Kim, Kwang Ho;Rhee, Young-Woo
    • Korean Chemical Engineering Research
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    • v.56 no.1
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    • pp.14-23
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    • 2018
  • The effect of dodecylbenzene sulfonic acid (DBSA) with different addition amount of DBSA ($M_{DBSA}$), temperatures and solvent-to-oil ratio (SOR, v/v) on asphaltene aggregation in a solvent deasphalting system was investigated. Increasing the $M_{DBSA}$ at SOR 10 and $55^{\circ}C$ caused the asphaltene removal ratio (ARR) to increase first, then maximize at 1 wt% of $M_{DBSA}$ and then decrease continuously. Based on the SARA (saturate, aromatic, resin, asphaltene) composition, the adsorption amount of DBSA on the asphaltene surface and the self-aggregation of the DBSA, the reason for the change in ARR with $M_{DBSA}$ was found due to the adsorption mechanism. In addition, the asphaltene-resin-DBSA colloidal size confirmed the change of adsorption behavior between the asphaltene and DBSA. Based on the results of this study, a hypothetical adsorption mechanism of DBSA on asphaltene aggregation in the solvent deasphalting system was conceived of and proposed.

The research of one-step emulsion polymerization of aniline and its conducting blends with polystyrene (에멀젼중합법으로 제조된 폴리아닐린과 폴리스타이렌과의 전도성블렌드에 대한 연구)

  • 이보현;김태영;김종은;서광석
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.259-262
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    • 2001
  • Stable polyaniline-dodecylbenzenesulfonic acid (PANI-DBSA) fully dissolved in toluene was obtained by a direct one-step emulsion polymerization technique. The polymerization of aniline was carried out in an emulsion comprising water, toluene and DBSA acting both as a surfactant and a dopant for PANI. After the proper washing process was performed, the conductivities of obtained PANI-DBSA complexes increased with increase APS/Aniline molar ratio and DBSA/Aniline molar ratio. The UV-Vis absorption spectra and TGA thermograms of PANI-DBSA complexes also supported these results. PANI-DBSA/PS blends were prepared by mixing PANI-DBSA complexes with PS in toluene. These blends exhibited electrical conductivity of 0.371S/cm at a low PANI-DBSA content (7 wt.%)

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Influence of Polymer Morphology and Dispersibility on Mechanical Properties and Electrical Conductivity of Solution-cast PANI-DBSA/HIPS Blends (용액 캐스팅으로 제조한 PANI-DBSA/HIPS 블렌드에서 분산성 및 모폴로지가 기계적 특성과 전기전도도에 미치는 영향)

  • Lee, Jong-Hyeok;Choi, Sun-Woong;Kim, Eun-Ok
    • Polymer(Korea)
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    • v.35 no.6
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    • pp.543-547
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    • 2011
  • A study has been done to enhance the mechanical properties and processability of electrically conductive polyaniline(PANI) without the polymer's structural alternation. Functionalized acid doped PANI (PANI-DBSA) was prepared by an emulsion polymerization, and dodecylbenzenesulfonic acid (DBSA) played both roles of surfactant and dopant. Also, PANI-DBSA was solution cast blended with high impact polystyrene (HIPS) to produce PANI-DBSA/HIPS blend film. The structure and electrical properties of the conducting polymer blends were observed through UV-vis and FTIR/ATR spectroscopy. A study of the blend was carried by focusing on observation of mechanical and electrical properties based on dispersibility and changes in polymer morphology. The conductivity of the blends was increased by increasing the content of PANI-DBSA, and the sudden increase of conductivity to $3.5{\times}10^{-4}$ S/cm was observed even under a low content of 9 wt%. There was a strong association of continuous network formation with percolation and conductivity in the conducting polymer blends.

Synthesis and Characteristics of Organic Soluble Polyaniline by Emulsion Polymerization (유화 중합법에 의한 유기 용매 가용형 폴리아닐린의 합성 및 그 특성)

  • 김진열;권시중;한성원;김응렬
    • 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.

Characterization of DBSA and Mixed Dopant Doped Stretchable Polypyrrole Films by Electrochemical Method (전기화학적 방법에 의한 DBSA와 혼합도판트로 도핑된 연신성 폴리피롤 필름의 특성)

  • Jang, Kwan-Sik;Moon, Bong-Jin;Oh, Eung-Ju;Hong, Jang-Hoo
    • Journal of the Korean Electrochemical Society
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    • v.6 no.2
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    • pp.134-140
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    • 2003
  • Stretchable Polypyrrole films(Ppy-DBSA, Ppy-mixed dopants) using functionalized doping agents dodecyl-benzensulfonic acid (DBSA) and mixed dopants{DBSA with $LIClO_4$, NSA (2-naphthalenesulfonic acid), DEHSA [di(2-ethylhexyl)sulfosuccinic acid]}, were synthesized by electrochemical method. Electrochemically prepared Polypyrrole films were stretch-oriented $(L/L_0=1.0-2.5)$ by a Bone drawing method and their electrical conductivities were measured. As the drawing ratio was increased, the electrical conductivities were increased. This results might be due to the increase in crystallinity through the incresase in draw ratio. The results of temperature dependence of electrical conductivity showed that power raw $(L/L_0=1.0-2.5)$ gave the best fit to the data for stretched Ppy-DBSA and Ppy-mixed dopants films.

Pedicled sural flaps versus free anterolateral thigh flaps in reconstruction of dorsal foot and ankle defects in children: a systematic review

  • Beecher, Suzanne M.;Cahill, Kevin C.;Theopold, Christoph
    • Archives of Plastic Surgery
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    • v.48 no.4
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    • pp.410-416
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    • 2021
  • Background This systematic review compared free anterolateral thigh (ALT) flaps versus pedicled distally based sural artery (DBSA) flaps for reconstruction of soft tissue defects of dorsal foot and ankle in children. Methods A systematic literature search was performed to identify cases where an ALT or DBSA was used to reconstruct the dorsal foot in children. A total of 19 articles were included in the systematic review. Results Eighty-three patients underwent an ALT reconstruction and 138 patients underwent a DBSA reconstruction. Patients who had a DBSA were more likely to require grafting of the donor site (P<0.001). The size of ALT flaps was significantly larger than DBSA flaps (P=0.002). Subsequent flap thinning was required in 30% of patients after ALT and 12% of patients after DBSA reconstruction (P<0.001). Complications occurred in 11.6% of DBSA and 8.4% of ALT flaps (8.4%). Conclusions Both flaps are valid options in reconstructing pediatric foot and ankle defects. Each flap has advantages and disadvantages as discussed in this review article. In general for larger defects, an ALT flap was used. Flap choice should be based on the size of the defect.

Preparation of pseudo n-type Polyaniline and Evaluation of Electrochemical Properties (가상 n형 폴리아닐린의 제조 및 전기화학적 특성평가)

  • 김래현;최선용;정건용
    • Membrane Journal
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    • v.13 no.3
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    • pp.162-173
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    • 2003
  • The pseudo n-type polyaniline was prepared by doping of camphorsulfonic acid(CSA) and dodecylbenzenesulfonic acid(DBSA) as the dopants in solvent of N-methyl-2-pyrrolidinone(NMP). The dopants in polymer structure was qualitatively analyzed using FT-IR. The influence on electrochemical properties with dopant concentration of PANI film were investigated. The electrochemical characteristics of the n-type PANI electrode that coated on ITO were evaluated by cyclic voltammetry(CV) and AC impedance method. The prepared PANI were confirmed as n-type PANI from FT-IR and CV. The charge transfer resistance of film on PANI/CSA electrode were measured as 1.14{\sim}1.09k{\mu}$by AC impedance. The charge transfer resistance of PANI/DBSA electrode decreased with increasing the mole ratio of DBSA as 27.73{\sim}8.37 k{\mu}$. The double layer capacitance of PANI/CSA electrode was showed almost constant value as $13.47{\sim}14.59 {\mu}F$ and that of PANI/DBSA electrode increased with increasing mole ratio of DBSA from 0.49 to $1.20 {\mu}F$.

Thermal and Electrical Behaviors of Polyethylene Oxide/Polyaniline Fibers Prepared by Electrospinning Method (전기방사법에 의해 제조된 폴리에틸렌옥사이드/폴리아닐린 섬유의 열적 및 전기적 거동)

  • Kim, Seok;Cho, Mi-Hwa;Park, Soo-Jin
    • Applied Chemistry for Engineering
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    • v.17 no.1
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    • pp.16-21
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    • 2006
  • In this study, PEO blend fibers mixed with polyaniline (PANI)/10-camphor sulfonic acid (CSA) and PANI/dodecylbenzene sulfonic acid (DBSA) were electro spun to investigate the influence of PANI content. CSA and DBSA were used as a functionalized doping acid having a bulky volume. PANI/PEO blend solution was prepared by dissolving PEO and PANI doped with CSA or DBSA. The thermal properties were measured by thermogravimetric analyzer (TGA). As a result, with increasing of the PANI content in PANI/CSA and PANI/DBSA, although initial decomposition temperature (IDT) was decreased, thermal stability was increased due to the increase of $A^*{\cdot}K^*$ and integral procedural decomposition temperature (IPDT). The electrical conductivities measured by the 4-probe method. The electric conductivity was increased with increasing of PANI content in PANI/CSA and PANI/DBSA. However, electrical conductivity did not change significantly beyond 30% content of PANI. From CV results, PANI/CSA showed the better defined peak shpae and higher peak current density compared to PANI/DBSA. This was probably related to the slightly higher electrical conductivity or better morphology for easy charge transfer in the case of PANI/CSA.

Preparation of Nylon6,6/Polyaniline Conducting Composite and Their Electrical Properties with the Content of Plasticizer (가소제 첨가에 따른 Nylon6,6/Polyaniline 전도성 복합체의 제조 및 전기적 성질)

  • Lee, Wan-Jin;Kim, Hyo-Yong
    • Applied Chemistry for Engineering
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    • v.9 no.7
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    • pp.979-984
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    • 1998
  • The conducting composites were prepared by blending of polyaniline(PANI) as conducting polymer and nylon6,6 as matrix in m-cresol. The PANI was protonated with alkylbenzenesulfonic acid such as camphorsulfonic acid(CSA) or dodecylbenzenesulfonic acid(DBSA). The miscibility of the composites was improved and the electrical conductivity was increased by adding dioctylphthalate(DOP). The electrical conductivity of the composites depending on the amount of protonating agent and PANI complex and the morphology were investigated. When it was protonated with DBSA having long alkyl chain and the content of PANI complex was 25 wt%, the electrical conductivity of the compsosite was increased up to 1.02 S/cm.

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