• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.303-309
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• 2009

The effects of zeolite type catalysts addition on the thermal decomposition of low density polyethylene(LDPE) and ethylene vinyl acetate(EVA) resin have been studied in a thermal analyzer(TGA, DSC) and a small batch reactor. The zeolite type catalysts tested were natural zeolite, FCC catalyst, used FCC catalyst, and catalyst A. As the results of TGA experiments, addition of antifogging-agent decreased the pyrolysis point to $250^{\circ}C$, but addition of longevity-agent and clay reduced the pyrolysis rate in EVA resin. Addition of the zeolite type catalysts in the LDPE resin increased the pyrolysis rate in the order of catalyst A > used FCC catalyst > natural zeolite > LDPE resin. Addition of the zeolite type catalysts in the EVA resin increased the pyrolysis rate in the order of used FCC catalyst > natural zeolite > catalyst A > EVA resin. In the DSC experiments for LDPE resin, addition of zeolite type catalysts decreased the melting point and the heat of pyrolysis reaction in the order of catalyst A > used FCC catalyst > natural zeolite> LDPE resin. In the batch system experiments, the mixing of natural zeolite enhanced the yield of liquid fuel oil.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2075-2078
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• 2007

Oligomerization of isobutene has been investigated using a few solid acid catalysts in order to produce efficiently triisobutenes that are useful chemical feedstocks for heavy alkylates and neo-acids. Several reaction conditions such as space velocity and isobutene concentration are evaluated, and a few cation exchange resins with various acid capacities were compared in the reaction. High trimers selectivity and high conversion can be obtained over a catalyst containing high acid capacity at low space velocity and relatively low isobutene concentration. The stability of a catalyst for the reaction is high when the acid capacity of the catalyst is high (for example Amberlyst-35).

• Macromolecular Research
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• v.17 no.3
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• pp.144-148
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• 2009

Poly(1-oxo-2-phenyltrimethylene) was synthesized by palladium-catalyzed copolymerization of styrene and carbon monoxide in quaternary ammonium ionic liquids. The $[Pd(bipy)_2][PF_6]_2$ compound had relatively more catalytic activity than $[Pd(bipy)_2][BF_4]_2$ in ionic liquids. The catalytic activity of palladium (II) composite catalyst was superior to the catalyst formed in situ from palladium acetate, 2,2-bipyridyl, and $X^-$ ($X^-=PF_6^-$, $BF_4^-$) in ionic liquids. The effects of the volume of ionic liquids, reaction time and benzoquinone content on the copolymerization were also described.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1028-1029
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• 2003

The copolymerization of ethylene and norbornene was carried out with ansa-metallocene and modified methylaluminoxane (MMAO) cocatalyst. The copolymerization behavior was changed with the structure of metallocene catalysts. In addition the catalyst activity was dependent on the structure of MMAO, i.e.. MMAO-4 which contains less i-butyl group compared to MMAO-3A exhibited higher catalyst activity than MMAO-3A. The glass transition temperature and the composition of the produced copolymer were not affected by MMAO type.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4297-4303
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• 2011

Under solvent-free conditions, the synthesis of propargylic alcohols by direct addition of terminal alkynes to aldehydes promoted by ZnO as a novel, commercially, and cheap catalyst is described. Furthermore, the catalyst can be reused for several times without any significant loss of its catalytic activity.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3156-3158
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• 2010

Stable and non-hygroscopic polystyrene supported aluminium triflate (Ps-$Al(OTf)_3$), which is prepared easily from cheap and commercially available compounds was found to be an environmentally friendly heterogeneous catalyst for Friedel-Crafts acylation of arenes using acid chlorides in the absence of solvent under mild reaction conditions. The catalyst can be reused up to five times after simple washing with dichloromethane.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1320-1322
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• 2008

Phosphomolybdic acid supported on silica gel (PMA-$SiO_2$) is an efficient catalyst for the activation of TMSCN for the facile cyanosilylation of various aldehydes. Cyano transfer from TMSCN to aldehyde proceeds smoothly at rt in presence of 0.8 mol % of PMA-$SiO_2$ leading to a range of cyanosilylether in excellent yield (mostly over 93%) within short reaction time (30 min). The catalyst can be recovered and reused several times without loss of activity.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1164-1166
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• 2009

Aromatic aldehydes are efficiently self-condensed into $\alpha$-hydroxy carbonyl compounds by polystyrene-supported ammonium cyanide as an excellent organocatalyst in C-C bond formation. The reaction proceeds in water under mild reaction conditions. The polymeric catalyst can be easily separated by filtration and reused several times without appreciable loss of activity.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1071-1076
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• 2009

N,N,N′,N′-tetramethylethylenediamine (TMEDA) acts as a simple, mild and efficient catalyst for the acylation of alcohols, phenols and thiols at room temperature under solvent-free condition. Acylation reaction with acetic anhydride and benzoic anhydride proceeds with good to excellent yield in the presence of TMEDA as the catalyst.

• Bulletin of the Korean Chemical Society
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• v.22 no.4
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• pp.375-378
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• 2001

The palladium catalyzed dehalogenative homocoupling of haloarylsulfonates under reductive conditions has proceeded selectively depending on the type of the halogen. Thus, an iodo or a bromo leaving group of haloarylsulfonates was homocoupled to gi ve symmetrical biaryls in good yields with the sulfonate group intact, whereas a chloro leaving group gave no reaction under the conditions used. When the more reactive nickel catalyst was employed instead of the palladium catalyst in the reaction, both dehalogenative and desulfonative homocouplings of haloarylsulfonates occurred regardless of the type of the halogen used.