• Title/Summary/Keyword: Acetylene

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Copolymerization of Phenyl Acetylene with Styrene (Phenyl Acetylene과 Styrene의 共重合)

  • Hyung Chick Pyun;Jaerok Kim;Woong-Moo Lee
    • Journal of the Korean Chemical Society
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    • v.13 no.4
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    • pp.387-393
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    • 1969
  • Gamma-ray induced copolymerization of phenyl acetylene with styrene is compared with that of the Ziegler catalyzed. The reactivity of styrene is greater than that of phenyl acetylene in the gamma-ray induced polymerization but much less than that of phenyl acetylene in the Ziegler catalyzed. The resulting copolymer is identified by means of DTA and spectrophotometry. Further, the liquid scintillation counting of styrene-${\alpha}-C^{14}$clarified the relative composition of the copolymers.

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A Study on the Dynamic Viscoelasticity of EVA/Acetylene Black Composites (EVA/Acetylene Black 복합체의 동역학적 점탄성 분석)

  • Lee, Kyoung-Yong;Yang, Jong-Seok;Choi, Yong-Sung;Nam, Jong-Chul;Sung, Baek-Ryong;Park, Dong-Ha;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.140-141
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    • 2005
  • To measure elastic properties of semiconducting materials in power cable, we have investigated modulus of EVA/acetylene black composite showed by changing the content of acetylene black. The specimen was primarily kneaded in material samples of pellet form for 5 minutes on rollers ranging between 70[$^{\circ}C$] and 100[$^{\circ}C$]. Then this was produced as sheets after pressing for 20 minutes at 180[$^{\circ}C$] with a pressure of 200[kg/cm]. The contents of conductive acetylene black were 20, 30 and 40[wt%], respectively. The modulus experiment was measured by DMA 2980. The ranges of measurement temperature were from -50[$^{\circ}C$] to 100[$^{\circ}C$] and measurement frequency is 1[Hz]. The modulus of specimens was increased according to an increment of acetylene black content. And modulus was rapidly decreased at the glass transition temperature. The tan$\delta$ of specimens was decreased according to an increment of acetylene black content.

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A Study on the Dielectric Properties and Viscoelasticity of EEA/Acetylene Black Composites (EEA/Acetylene Black 복합체의 유전특성과 점탄성에 관한 연구)

  • Lee, Kyoung-Yong;Yang, Jong-Seok;Choi, Yong-Sung;Nam, Jong-Chul;Sung, Baek-Ryong;Park, Dong-Ha;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.138-139
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    • 2005
  • To measure electrical properties and viscoelasticity of semiconducting materials in power cable, we have investigated dielectric properties and modulus of EEA/acetylene black composite showed by changing the content of acetylene black. The permittivity from experimental result was increased, while tan6 was decreased by an increment of the content of acetylene black. The modulus of specimens was increased according to a increment of a acetylene black content. And modulus was rapidly decreased at the glass transition temperature. The tan$\delta$ of specimens was decreased according to a increment of a acetylene black content.

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C$_2H_2$ chemisorption for characterization of carbon black active sites (카본블랙 활성점 연구를 위한 아세틸렌 화학흡착)

  • Lee, Sang-Yup;Kwak, Jung-Hun;Yoon, Ki-June
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.80-83
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    • 2007
  • In order to characterize the catalytically active sites on carbon black, acetylene chemisorption had been examined recently at 773 and 873 K by using a pulse technique. As the inject ion was repeated at 773 K, the adsorbed amount gradually decreased and eventually the adsorption did not occur any more. At 873 K a constant amount of $C_2H_2$ was consumed repeatedly after several injections. Good linear relationships were obtained between the methane decomposition rate at 1123 or 1173 K and the cumulative acetylene adsorption at 773 K or the constant acetylene consumption at 873 K. Reasonable models for the associative acetylene chemisorption at 773 K and the constant acetylene consumption at 873 K on the armchair face at the edges of graphene layers were proposed. The constant consumpt ion may be explained by the "$C_2H_2$-addition-hydrogen- abstract ion (CAHA)" mechanism.

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Effect of Carbon Black on Mechanical and Damping Properties of EPDM/Carbon Black System (EPDM/Carbon Black계에서 Carbon Black에 따른 기계적 성질 및 방진 특성)

  • No, Tae-Kyeong;Kang, Dong-Guk;Seo, Jae-Sik;Yang, Kyung-Mo;Seo, Kwan-Ho
    • Elastomers and Composites
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    • v.47 no.3
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    • pp.231-237
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    • 2012
  • This study measured the mechanical and damping properties of EPDM compounds including fillers. Semi-reinforcing furnace black (SRF), high abrasion furnace black (HAF) and acetylene black were used as fillers. Dicumyl peroxide (DCP) were used as curing agents. The measurements were conducted using a moving die rheometer (MDR), durometer, universal testing machine (UTM), compression set and dynamic mechanical analysis (DMA). The tensile strength and elongation at break increased with increasing SRF contents in EPDM compounds. However, they decreased with increasing the amount of acetylene black. In the inspecting temperature range, EPDM compound filled acetylene black had stable storage modulus. Furthermore, the tan ${\delta}$ of the EPDM compounds obtained was enhanced by compounding with acetylene black.

Reactions of Acetyl Radical with Acetylene - A Computational Study

  • Tran, Tu Anh;Schiesser, Carl H.
    • Bulletin of the Korean Chemical Society
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    • v.31 no.3
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    • pp.595-598
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    • 2010
  • Ab initio and DFT molecular orbital calculations predict that acetyl radical reacts with acetylene through interactions primarily involving the SOMO of the radical and the in-plane ${\pi}$-bond of acetylene. An energy barrier (${\Delta}E_1$) of 39.6 kJ $mol^{-1}$ is predicted for the preferred anti arrangement of reactants at the CCSD(T)/cc-pVDZ//BHandHLYP/cc-pVDZ level of theory. NBO analysis reveals additional interactions between the radical SOMO and the nearby C-H ${\sigma}$-bond in acetylene worth about 10% of the total transition state interaction energy. This type of orbital interaction has not previously been observed in radical addition reactions involving C-C ${\pi}$-bonds.

Aromatic Formation from Vinyl Radical and Acetylene. A Mechanistic Study

  • Natalia, Debby;Indarto, Antonius
    • Bulletin of the Korean Chemical Society
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    • v.29 no.2
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    • pp.319-322
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    • 2008
  • The viability of acetylene addition in each step of aromatic formation initiated by vinyl radical and acetylene also with its competition with structure rearrangement is investigated by determining optimal geometries and barrier and reaction energies using quantum mechanical methods. In principle, the addition reaction has more difficult in term of free energy and enthalpy compared to geometry arrangement. Under combustion conditions, i.e. T = 1200 K, acetylene addition is unfavorable mechanism as the barrier energy values rise much higher than that of geometry arrangement. However, in longer chain hydrocarbon case, e.g. n-CxHx+1 where x ³ 8, C-C bond rotation is rather difficult and requires high energy to form a ring structure, elongation chain is preferable.

EFFECTS OF SPLIT INJECTION AND OXYGEN-ENRICHED AIR ON SOOT EMISSIONS IN A DIESEL ENGINE

  • Nguyen, Khai;Sung, Nak-Won;Lee, Sang-Su
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2965-2970
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    • 2008
  • Effects of split injection and oxygen-enriched air on soot emissions in a DI diesel engine were studied by the KIVA-3V code. When split injection is applied, the second injection of fuel into a cylinder results in two separate stoichiometric zones which increases soot oxidation. As a result, soot emissions are decreased with split injection. When oxygen-enriched air is applied together with split injection, higher concentration of oxygen helps secondary combustion which results in a higher temperature in the cylinder. The increased temperature promotes growth reaction of acetylene with soot but doesn't improve the acetylene formation during the second injection of fuel. As more acetylene is consumed in the growth reaction of acetylene, the net acetylene mass in the cylinder is decreased, which leads to a decrease of soot formation. With an increase of soot oxidation caused by split injection, the soot emissions are decreased significantly. However, to avoid excessive NOx emissions with increased oxygen concentration, the level of oxygen concentration should be lower than 22% in volume.

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Production of Acetylene Black/silica Composite Particles by Adsorption of Polyethylenimine (Polyethyleneimine 흡착에 의한 아세틸렌 블랙/실리카 복합체 입자 제조)

  • Lee, Jeong-Woo;Park, Jung-Hwan;Shim, Sang-Eun
    • Elastomers and Composites
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    • v.45 no.1
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    • pp.7-11
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    • 2010
  • The acetylene black/silica composite particles were prepared by a simple and fast method using polyethylenimine (PEI) as a coupling agent. The composite particles were produced via the following two steps; adsorption of PEI on the surface of acetylene black particles and synthesis of silica by sol-gel process. The morphology of the composite particles was a core-shell, and a large number of micropores was created after silica was synthesized on the acetylene black surface.

Electron-Impact Ionization Mass Spectroscopic Studies of Acetylene and Mixed Acetylene-Ammonia Clusters as a Structure Probe

  • Sung Seen Choi;Kwang Woo Jung;Kyung Hoon Jung
    • Bulletin of the Korean Chemical Society
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    • v.13 no.5
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    • pp.482-486
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    • 1992
  • Ion-molecule reactions of acetylene and mixed acetylene-ammonia cluster ions are studied using an electron impact time-of-flight mass spectrometer. The present results clearly demonstrate that $(C_2H_2)_n^+$ cluster ion distribution represents a distinct magic number of n=3. The mass spectroscopic evidence for the enhanced structural stabilities of $[C_6H_4{\cdot}(NH_3)_m]^+$ (m=0-8) ions is also found along with the detection of mixed cluster $[(C_2H_2)_n{\cdot}(NH_3)_m]^+$ ions, which gives insight into the feasible structure of solvated ions. This is rationalized on the basis of the structural stability for acetylene clusters and the dissociation dynamics of the complex ion under the presence of solvent molecules.