• The Korean Journal of Food And Nutrition
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• v.12 no.6
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• pp.597-601
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• 1999

Chitosan을 Bacillus pumilus BN-262 유래의 chito-sanase로 처리한 경우에는 trimet, tetramer, pentamer 가 전체 올리고당 중 64,3%에 달하는 비교적 저분자의 chitooligosaccharides로 구성괸 chitooligosacch-aride I을 얻을수 있었다 그러나 Trichoderma viride 유래의 cellulase로 처리한 경우에는 중합도 7이상의 것이 전체 올리고당 중 49.3% 에 달하는 상대적으로 분자량이 큰 chitooligosaccharides로 구성된 chitoolig-osaccharide II을 얻을수 있었다. 따라서 생리적 기능성이 높은 hexamer 이상의 chitooligosaccharides를 얻기 위해서는 chitosanase의 처리조건을 달리하여 분해가 덜 일어나도록 하거나 cellulase와 같은 효소를 처리함으로써 chitosan의 부분적인 분해를 유도하는 것이 필요하고 판단되었다. Chitin과 chitooligosac-charides의 응집성에 대하여 조사하였다 고분자의 chitosan은 2가 음이온을 함유하는 무기화합물 및 고분자의 유기화합물과 반응하여 응집이 일어났다. 분해가 많이 일어난 chitooligosaccharide I 은 무기물질과는 침전하지 않았으나 고분자화학불을 함유하는 유기화합물과는 반응하여 침전이 일어났다 분해가 적게 일어난 chitooligosaccharide II 는 2가 음이온을 함유하는 무기화합물 및 고분자의 유기화합물과 반응하여 침전이 일어났다.

• Polymer Science and Technology
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• v.10 no.6
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• pp.791-804
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• 1999

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.504-508
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• 2021

In this study, the effect of molecular features of guest molecules on the structure, property, and formation of poly(vinyl alcohol) (PVA)/beta-cyclodextrin (bCD) inclusion compound hybrid films was investigated using three types of guest molecules such as hydroquinone (HQ), arbutin (AB), and tranexamic acid (TA). First, the successful formation of inclusion compounds between bCD and the guest molecules, and polymer/inclusion compound hybrid were proved using Raman spectroscopy. The effect of bCD-based inclusion compounds on the structure and property of PVA matrix composites containing inclusion compounds was also studied using X-ray diffraction (XRD) and thermal analyses such as differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). It was notable that the effect of TA to the crystalline structure of the PVA was significantly different from that of using other guest molecules including HQ and AB. It was also supported by a simple molecular simulation result. This article will be a good example for demonstrating the effect of molecular characteristics on the inclusion compound formation in polymer films, which can provide important information for relevant future research.

• Journal of the Korean Electrochemical Society
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• v.19 no.2
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• pp.29-38
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• 2016

Screen printed carbon electrodes (SPCEs) with immobilized osmium-based hydrogel redox polymer, uricase and PEGDGE can be used to apply uric acid electrochemical detecting. The osmium redox complexes were synthesized by the coordinating pyridine group having different functional group at 4-position with osmium compounds. The synthesized poly-osmium hydrogel complexes are described as PAA-PVI-$[Os(dCl-bpy)_2Cl]^{+/2+}$, PAA-PVI-$[Os(dme-bpy)_2Cl]^{+/2+}$, PAA-PVI-$[Os(dmo-bpy)_2Cl]^{+/2+}$. The different concentrations of uric acid were measured by cyclic voltammetry technique using enzyme-immobilized SPCEs. The prepared SPCEs using PAA-PVI-$[Os(dme-bpy)_2Cl]^{+/2+}$ showed no interference from common physiologic interferents such as ascorbic acid (AA) or glucose. The resulting electrical currents at 0.33 V vs. Ag/AgCl displayed a good linear response with uric acid concentrations from 1.0 to 5.0 mM. Therefore, this approach allowed the development of a simple, point of care in the medical field, disposable electrochemical uric acid biosensor.

• Polymer Science and Technology
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• v.5 no.3
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• pp.215-226
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• 1994

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.111-112
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• 2006

실리콘을 기반으로 한 micro-Total Analysis Systems(${\mu}$-TAS)이 출현한 이후에, 현재까지 다양한 고분자 화합물을 이용한 유체소자의 연구가 진행중이다. 고분자 화합물은 실리콘과 유리를 이용한 전통적인 유체소자 재료에 비해 재료의 경제성과 소자 제작의 용이성 그리고 처리하고자 하는 유체에 맞는 다양한 재료를 선택할 수 있다는 장점을 지니고 있다. 하지만 고분자 화합물의 표면 에너지가 실리콘과 유리에 비해 낮은 단점을 가지고 있다. 이러한 문제를 극복하기 위해 다양한 표면처리 연구가 이루어져왔다. 레이저를 이용한 표면처리는 실험장치가 간단하고 대기 중에서 실시할 수 있다는 장점을 가지고 있다. 본 연구에서는 Nd:YAG 레이저(${\lambda}$=266 nm, pulse)를 이용하여 유체소자 재료로써 많이 사용되는 polymethly methacrylate(PMMA)의 표면개질을 시도하였다. 표면처리 후 접촉각 측정기를 이용하여 표면개질 정도를 확인한 결과, 표면 산소 함유량이 증가됨에 따라 접촉각이 감소하였다. 결론적으로 PMMA의 본래 성질은 유지한 채 레이저 표면처리를 이용한 표면 에너지 증가 효과를 볼 수 있었다.

• Polymer Science and Technology
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• v.12 no.3
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• pp.312-322
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• 2001

• Journal of the Korea Concrete Institute
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• v.28 no.2
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• pp.197-204
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• 2016

Concrete walls of neutron generating facilities such as fusion reactors and fission reactors become radioactive by neutron irradiation. Both low-activation and neutron shielding are a critical concern at the dismantling stage after the shutdown of facilities with a requirement of radioactive waste management. To tackle this, two types of additives were investigated in fabricating mortar specimens: synthetic high polymers and boron carbide. It is well known that a hydrogen atom is effective in neutron shielding by an elastic scattering because its mass is almost the same as that of the neutron. And boron is an effective neutron absorber with a big neutron absorption cross section. In this study, the effect of the type, shape, and size of polymers were investigated as well as that of boron carbide. Total 16 mix designs were prepared to reveal the effect of polymers on mechanical properties and neutron shielding performance. The neutron does equivalent of polymers-based mortar for fast neutrons decreased by 36 %, and the count rate of boron carbide-based mortar with regard to thermal neutrons decreased by 90 % compared to conventional mortar. These results showed that a combination of polymers and boron carbide compounds has potential to reduce the thickness of neutron shields as well as radioactive waste from reactors.

• Journal of the Korean Ceramic Society
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• v.36 no.2
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• pp.151-158
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• 1999

$\varepsilon$-Caprolactame as organic monomer was intercalated in the interlayer space of montmorillonite and polymerized by polymerization reaction so that the inorganic polymer and organic polymer could be combined each other by chemical bonding. The results of X-ray and IR analysis showed that the polymerization reaction of $\varepsilon$-caprolactame between the interlayer spaces has been performed sucessfully. In order to study polymeric reaction product in detail we have isolated the polymerized material from the interlayer space and analyzed it by X-ray diffractometer and IR-Spectrocopy. The comparison of these results with them of the analyses for thee pure polymer which has been synthesized by polymeric reaction of $\varepsilon$-carolactame without montmorillonite showed that the obtained both polymeric materials are the same compounds.

• Polymer Science and Technology
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• v.1 no.2
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• pp.89-96
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• 1990