• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1031-1037
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• 2018

The formation of a complex between PVP or HPC and iodine was indicated by a red shift in the tri-iode band while PVA-iodine complex showed its characterized band around 500 nm in pure aqueous media. Addition of surfactant SDS resulted in a disapperance of the characteristic blue color of the PVA-iodine complex indicating that the complex is not formed in aqueous surfactant media. However in case of PVP or HPC, presence of the monomers of SDS favored the complex formation but in higher concentration, the micelles of SDS decreased the complex. Complexation was found to increase with increasing content of n-propanol in the system since n-propanol inhibits the formation of gels or microgels in the polymer solution. But in case of PVA-iodine complex, addition of n-propanol led to conversion of bigger polyiodides into smaller ones, which is indicative of increased intermolecular hydrogen bond interaction between propanol and PVA effecting a decrease in the PVA aggregate space.

• Journal of the Korean Chemical Society
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• v.19 no.6
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• pp.454-462
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• 1975

The photodegradation of polystyrene and polyethylene was studied utilizing several additives to promote photooxidation. Polymer films with small amount of additives were irradiated with ultraviolet lamps in Rayonet Photochemical Reactor. The progress of photodegradation was followed by measuring the intensities of carbonyl and hydroxyl stretching bands in infrared spectra as well as the viscosity changes. It was found that the increase of carbonyl or hydroxyl peaks was proportional to the decrease of the molecular weight of polymers under study. Iron(II, III) complexes of dithiocarbamate and their analogs showed good results.

• Polymer Science and Technology
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• v.5 no.3
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• pp.236-253
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• 1994

양이온형 $d^0\;Cp_2M(R)(L)^+$ 착물과 무염기 $Cp_2M(R)^+$ 착물은 $Cp_2M(R)_2$화합물로부터 쉽게 합성할 수 있다. 이들 친전자성 착물에서는 여러가지 리간드 교환반응, 삽입반응, ${\beta}$-H 제거반응 및 ${\sigma}$-결합 복분해반응이 일어날 수 있다. 일반적으로 $Cp2M(R)(L)^+$ 착물은 불포화도와 전하가 크기때문에 중성의 $Cp_2M(R)(X)$나 $Cp_2M(R)_2$보다 반응성이 크며 $d^0\;{Cp_2}^*M(R)^+$ (M=제 3족과 란탄계) 착물과 여러가지 반응에서 유사한 거동을 보인다. $Cp_2MX_2$를 기초로하여 합성된 Ziegler-Natta 촉매에 의한 올레핀 중합에서 활성점이 $Cp_2M(R)^+$ 양이온이라는 여러가지 직접적인 증거가 발표되었다. 분리가능한 $Cp_2M(R)(L)^+$ 착물은 올레핀중합에서 높은 활성을 보이며, 유기합성의 관점에서 흥미있는 C-C 재조합반응과 같은 다른 여러가지 반응이 일어날 수 있는 기회를 제공한다.

• Membrane Journal
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• v.24 no.6
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• pp.472-483
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• 2014

This study is preparation of microporous membranes by using macrocyclic metal ion complexes and extended cage complexes. It is a more favorable way to existing methods because polymer and metal ion-ligand complex system provides a fine control over the phase transition behavior. Chemical functionalization of the polar surface can be obtained. Metal-templated condensation of cyclohexanedione dioxime, hydroxyphenylboronic acid in the presence of metal salts proceeds cleanly in methanol to furnish the metal clathrochelate complexes. Organic/inorganic hybrid membranes were prepared with polyethersulfone (PES), polyvinylpyrrolidone (PVP), ethyleneglycol butyl ether (BE), metal clathrochelate s and DMF by using nonsolvent induced phase inversion method. The structure of membranes was characterized with scanning electron microscopy (SEM) and microflow permporometer. The addition of Fe(II) clathrochelate complex with p-hydroxyphenyl group leads to changes of membrane morphology such as narrow mean pore size distribution, increase of surface pore density and decrease of the largest pore size.

• Polymer(Korea)
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• v.24 no.2
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• pp.252-258
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• 2000

Various crosslinked poly(4-vinylpyridines) (CHP4VP) having different degrees of crosslinking were synthesized by radical copolymerization of 4-vinylpyridine with if N,N' -1, 6-hexamethylenebisacrylamide, and CHP4VP- Cu(II) complexes were prepared by the method of adsorption equilibrium. The catalytic activity of the complexes for the oxidation of ascorbic acid (AA) was investigated. The oxidation of AA by these complexes showed a kinetic behavior of the Michaelis-Menten type. The catalytic activity of CHP4VP-Cu(I ) catalytic system was increased with increasing the degree of crosslinking of CHP4VP, and its activity was scarcely decreased even after repeated use. However, the tendency of the catalytic activity of CHP4VP-Cu(II) complexes was decreased for the oxidation of AA when compared with that of the previously reported catalytic system containing crosslinked poly(4-vinylpyridine) prepared using N,N'-methylenebisacrylamide as a crosslinker. These results indicate that the degree of crosslinking of CHP4VP and the hydrophobicity of the crosslinker play an important role in the catalytic system of the oxidation of AA.

• Journal of the Korean Chemical Society
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• v.25 no.6
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• pp.394-398
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• 1981

Two types of Ni(II)-polyethyleneimine (PEI) complexes, [Ni(PEI)]$Cl_2$ and [Ni(P-EI)$Cl_2$] were synthesized and their catalytic activities in the decomposition reaction of hydrogen peroxide were investigated. For the purpose of comparison, the corresponding monomeric complexes, $[Ni(en)_3]Cl_2$ and $[Ni(en)_2Cl_2$ were also prepared; it was observed that their activities increase in the following order; $0{\approx}[Ni(en)_3]Cl_2{\le}[Ni(en)_2Cl_2]<[Ni(PEI)]Cl_2<[Ni(PEI)Cl_2]$ On the basis of structural analysis by means of visible and infrared spectroscopy, the catalytic activiy of these Ni(II)-PEI complexes is assumed to depend on the bond strength between the ligand and the nickel ion.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.11a
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• pp.198-199
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• 2009

킬레이팅 고분자를 메조기공 탄소 표면 위에 흡착시킴으로써 금속이온과 착물을 형성할 수 있는 기능성 나노구조체를 제조하였다. 악티늄족 원소를 단일입자 내에 영구처분을 위한 예비연구로서 Eu을 대용물(surrogate)로 사용하여 기능성 나노 구조체에 주입한 후 메조기공 입구를 고분자반응을 통해 봉쇄함으로써 Eu의 단일입자 내 고정화를 시도하였다. 시간에 따라 침출현상을 분석한 결과, 고분자로 메조기공을 blocking 하였을 때 Eu의 침출현상이 크게 완화되는 것을 확인하였다. 이는 시멘트화나 유리화 등과 같은 고비용 공정을 거치지 않고도 단일입자 내 유해 금속의 영구처분이 가능하다는 것을 의미한다. 더 나아가, 이러한 접근방법은 지지체로 메조기공 탄소에 국한되지 않고 실리카와 같은 다른 메조기공 금속산화물에 적용될 수 있다는 점에서 큰 강점이 있다.

• Journal of the Korean Chemical Society
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• v.41 no.9
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• pp.502-517
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• 1997

This review deals with (1) the catalytic systems and mechanisms for the dehydropolymerization of silanes to polysilanes, (2) the dehydropolymerization of versatile silanes, (3) the preparation of polysilane derivatives, and (4) the applications of catalytic dehydropolymerizing systems to ceramics. The efforts to maximize the catalytic efficiency of group 4 metallocenes were introduced. Finally, the future of this dehydropolymerizing techniques of silanes was foreseen.

• The Journal of Engineering Research
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• v.3 no.1
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• pp.235-242
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• 1998

Hydrosilylation and vromination of vacterial poly($\beta$-Hydroxyalkanoates) containing carbon-carbon double bond or triple bond were carried out. The produced polymers were characterized by IR-spectroscopy and differential scnning calorimetry. Hydrosilylated polymers were characterized crystallinity while brominated polymers had lower degree of crystallinity with increased glass transition temperatures. Mixing polymers containing carbon-carbon triple bonds with Co(II) AND Pt(II) resulted crosslinked polymers.

• Polymer(Korea)
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• v.31 no.2
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• pp.136-140
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• 2007

Charge transfer interaction as a hybridization mechanism of silsesquioxane/polymer was tested using carbazole (electron donor) group and dinitrobenzene (electron acceptor) group. Hybridization test was conducted using films made from mixing/casting of poly (carbazole-styrene) (PS/D) and dimtrobenzyl silsesquioxane (Cube/A), and transparent hybrid films were successfully obtained under some conditions. $^1H-NMR$ of PS/D and Cube/A, and W absorption test of hybrid films showed that one acceptor and one donor can form one charge transfer complex when no silsesquioxane molecule was included in films, but transparent hybrids with no phase separation were obtained only at acceptor/donor ratios less than 0.7 : 1. These results also suggested that on average 4 charge transfer complexes form per one silsesquioxane.