• 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.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.127-128
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• 2014

현재 기술 산업에서 PET위 무전해 도금을 실행하기 위해 다양한 전처리 공정과 Catalyst가 소개되고 있다. 그 중에서 가장 일반적으로 사용되고 있는 Catalyst는 Palladium으로서 Tin과 산화 환원 반응으로 Electroless Copper Deposition 단계에서 구리 도금의 Target으로 작용하고 있다. 하지만 상대적으로 Palladium은 생산 비용이 높으며 Tin은 쉽게 산화되는 문제점이 남아 있다. 이를 대체하기 위한 대안 공정으로서 Palladium 대신 Silver를 이용하여 Catalyst로서의 역할을 하는 공정이다. 이전에 PET위 전처리 공정으로 Ultra Violet을 사용하여 표면을 개질 시키는 방법을 연구했으며, 그 후 Potassium Permanganate와 Silver Catalyst의 Mechanism을 연구 했다. PET 표면 개질을 거치면서 화학 구조가 바뀌어 표면에 Carbon Carbon Double Bond를 형성한다. 이때 Permanganate ion이 새로이 형성된 이중 결합과 반응하여 두 개의 extra-OH functional group을 생성함과 동시에 $MnO_2$를 만들어 표면에 흡착 시킨다. $MnO_2$는 전위차에 의해 Silver Ion과 Redox Reaction을 일으키며 실질적인 Catalyst 역할을 하게 된다. Silver Catalyst는 무전해 구리 도금 용액 안에서 Copper의 Target으로 작용한다.

• 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.

• Journal of Korean Society on Water Environment
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• v.31 no.5
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• pp.468-475
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• 2015

Various methods to degrade explosives efficiently in natural soil and water that include trinitrotoluene (TNT) have been studied. In this study, TNT in water was degraded by reduction with palladium (Pd) catalyst impregnated onto alumina (henceforth Pd-Al catalyst) and formic acid. The degradation of TNT was faster when the temperature of water was high, and the initial TNT concentration, pH, and ion concentration in water were low. The amounts of Pd-Al catalyst and formic acid were also important for TNT degradation in water. According to the experimental results, the degradation constant of TNT with unit mass of Pd-Al catalyst was $8.37min^{-1}g^{-1}$. The degradation constant of TNT was higher than the results of previous studies which used zero valent iron. 2,6-diamino-4-nitrotoluene and 2-amino-4,6-dinitrotoluene were detected as by-products of TNT degradation showing that TNT was reduced. The by-products of TNT were also completely degraded after reaction when both Pd-Al catalyst and formic acid existed. Even though there are several challenges of Pd-Al catalyst (e.g., deactivation, poisoning, leaching, etc.), the results of this study show that TNT degradation by Pd-Al catalyst and formic acid is a promising technique to remediate explosive contaminated water and soil.

• Journal of Korean Society for Atmospheric Environment
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• v.1 no.1
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• pp.43-51
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• 1985

This study is concerned with the oxidation of carbon monoxide on platinum and platinum-palladium catalysts. Catalysts were made by the impregnation method and flow reactor was used in the catalytic reaction. As for the mixed gases, carbon monoxide concentration varied from 1 to 4% and that of oxygen from 1 to 4%. $N_2$ was used as carrier gas and GHSV varied from 24, 000 $h^{-1} to 60, h^{-1}$. The temperature range was from 200 to $600^\circ$C. It was also taken into consideration that the heat and mass transfer resistance of our catalysts was negligible in the study. Experimental results showed that platinum-palladium catalyst was about 1.5-3.9% superior to platinum catalyst in conversion yield. When we used platinum-palladium catalyst, we observed that carbon monoxide oxidation was found to be 1 st order with respect to carbon monoxide concentration. Activation energy of the catalyst was 23.5 kcal/mol.

• Polymer(Korea)
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• v.39 no.3
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• pp.487-492
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• 2015

The effects of chemical structure of alkyl groups of norbornene carboxylic alkyl esters(methyl, octyl, 4-chlorobenzyl) and endo/exo ratios of norbornene monomers on activity of palladium catalyst and polymerization behavior were investigated. Norbornene ester monomers were synthesized from the reaction of 5-norborene-2-carboxylic acid and various alcohols. Polymerization catalyst, di-${\mu}$-chloro-bis(-methoxybicyclo[2,2,1]-hept-2-ene)palladium(II) (DCBMP), was synthesized according to the literature procedure and silver hexafluoroantimonate ($AgSbF_6$) was used as a conjugate anion source. Gel permeation chromatography (GPC), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) were the principal techniques for polymer characterization and $^1H$ NMR spectroscopy was used for chemical structures determination of monomers and polymers. For all of the norbonene alkyl esters GPC data showed that when the amounts of endo isomers exceeded those of exo isomers decreased molecular weight polymers were obtained probably due to the decreased catalyst activity. Polymerizations were conducted by varying the monomer/catalyst mole ratios (100:1, 200:1, 300:1). When 300:1 monomer/catalyst ratio was employed it was possible to synthesize high molecular weight ($M_n=27500g/mol$), film forming polymer from exo-norbornene carboxylic acid octyl ester.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.797-798
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• 2001

• YAKHAK HOEJI
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• v.37 no.6
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• pp.615-620
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• 1993

The cross-coupling reaction of organo tin reagents with a variety of organic halides, catalyzed by palladium, provides a novel method for generating a carbon-carbon bond. We used this method for the antibacterial agents, and synthesis of new quinolone derivatives which have carbon-carbon bond at C-7 position of general quinolone moieties. Aryl tin, quinolone moieties, and palladium catalyst were refluxed in DMF to afford new quinolone derivatives. This palladium catalyzed coupling reactions have capacity for further synthetic elaboration.

• Macromolecular Research
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• v.17 no.8
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• pp.563-567
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• 2009

In order to improve the thermomechanical performance of polyketone, a third monomer (4-methylstyrene) was added to the copolymerization system. The terpolymer of CO, styrene, and 4-methylstyrene was synthesized in the presence of multi component catalysts containing palladium acetate and rare earth metal phosphonates. The products were characterized by infrared spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR). The effects of the different components, including the third monomer, palladium acetate, 2,2'-bipyridyl, rare earth phosphonate, p-toluene-sulphonic acid, and p-benzoquinone, were also studied. The highest catalytic activity of 965.51 g/(gPd h) was obtained with a catalyst containing palladium acetate and rare earth phosphonate.

• Applied Chemistry for Engineering
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• v.24 no.1
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• pp.82-86
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• 2013

Palladium particles were synthesized with 1-buthyl-3-methylimidazolium trifluoromethanesulfonate ([Bmim][$CF_3SO_3$]) as an effective solvent during the synthesis. The morphology of the particles was affected by the concentration of [Bmim][$CF_3SO_3$]. Furthermore, the palladium on carbon powder was prepared with various [Bmim][$CF_3SO_3$] concentrations and calcinations temperatures as a catalyst for hexafluoropropylene hydrogenation. Catalytic activity was varied by both conditions significantly. Under the identical condition, the catalyst prepared by the same mole ratio of [Bmim][$CF_3SO_3$] and palladium, and calcined at $500^{\circ}C$ was the most active in this reaction.