• 한국막학회:학술대회논문집
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• 한국막학회 1998년도 춘계 총회 및 학술발표회
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• pp.89-92
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• 1998

1. Introduction : Among many azeotropic compounds, pyridine which forms an azeotropic mixture with three moles of water boiling at 92-93$\circ$C is very useful synthetic intermediate in laboratory and industry. With conventional separation method, the dehydration of pyridine aqueous solution is difficult and requires strong drying chemicals. To overcome these difficulties, several researchers have investigated on the separation of pyridine from aqueous solution through polymer membranes. Kujawski reported several ion-exchang membranes containing carboxylic and sulfonic fuctional group for dehydration of aqueous pyridine solution [1]. We have applied the idea of activation of water tranport through ion-dipole interactions between polymer membrane and aclueous feed. Our previous studies reported on the in-situ complex membrane to separate water from aqueous pyridine solution based on simple acid'-base theory [2, 3]. Water transport was enhanced through in-situ complex formation between the , acid moiety in the membrane and the incoming pyridine moiety in the feed.

• 한국염색가공학회지
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• 제3권2호
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• pp.43-48
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• 1991

Cellulose acetate (CA) and poly-4-vinyl pyridine (PVP) in various weight proportions were mixed in a mixed solvent of trifluoroacetic acid: methylene chloride/6:4 (v:v). CA was miscible with PVP in that solvent system. CA/PVP/solvent show liquid crystal in a certain range of concentration and the nature of that liquid crystal was cholesteric. Films of the liquid crystal composite cast from the liquid crystal solutions of CA/PVP were tested in a viewpoint of biomembrane. Results show that considering permselectivity CA/PVP membrane is better than that of CA and CA/PVP membrane is closer to cell membrane.

• Journal of Photoscience
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• 제1권2호
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• pp.113-117
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• 1994

The quantum yields of fluorescence ($\Phi$$_f$) and trans $\to$ cis photoisomerization ($\Phi$$_{t$\to$ c}$), trans-4-(2-(9-anthryl)vinyl)pyridine, an aza analogue of 1-(9-anthryl)-2-phenylethylene, were measured in several solvents at room temperature. $\Phi$$_f$ and $\Phi$$_{t$\to$ c}$ are 0.38 and < 0.01 in hexane and 0.02 and 0.38 in acetonitrile, respectively. As solvent polarity decreases, $\Phi$$_{t$\to$ c}$ strongly reduced, whereas $\Phi$$_f$ strongly increased. A singlet mechanism of trans $\to$ cis photoisomerization is suggested since $\Phi$$_{t$\to$ c}$ and $\Phi$$_f$ change in opposite direction.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1990년도 제2차 학술발표초록집
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• pp.70-70
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• 1990

• 한국미생물·생명공학회지
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• 제25권4호
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• pp.420-426
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• 1997

Pseudomonas sp. lipase (lipase AK) catalyzed transesterification reaction between fructose and vinyl laurate in anhydrous pyridine. The product of this process was identified as monoester of fructose and vinyl laurate. The synthetic product has been found to be an excellent emulsifier. The synthetic bioemulsifier showed a good emulsification activity and stability in comparison with other commercial emulsifiers, and good emulsification activity on various emulsifying substrates.

• 한국세라믹학회지
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• 제32권6호
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• pp.703-709
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• 1995

Octadecylenetrimethylammonium-montmorillonite as an organophilic montmorillonite intercalations complex was formed by cation exchange reaction between Na-montmorillonite and 9-octadecylenetrimethylammonium cation. After drying of this organophilic montmorillonite at $65^{\circ}C$ in high vacuum, the complexes were reacted with various swelling-solutions such as benzene, toluene, o-xylene, pyridine, $\alpha$-picoline, 2-ethyl-pyridine, 2-vinyl-pyridine and styrene, and the corresponding basal spacing obtained were 43.9$\AA$, 54.3$\AA$, 51.7$\AA$, 41.5$\AA$, 42.5$\AA$, 39.9$\AA$, 39.8$\AA$, 44.8$\AA$, respectively.

• 멤브레인
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• 제25권4호
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• pp.310-319
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• 2015

음이온 교환막의 치환체 특성을 파악하기 위하여 탄화수소의 분자구조가 다른 세 종류의 음이온 교환기를 vinyl benzyl chloride (VBC) base 막에 도입하였다. 지방족계로 trimethylamine (TMA), 고리형계로 N-methylpiperidine (MP), 방향족계로 pyridine (Py)은 아민화 반응을 통하여 도입되었다. 각각의 반응속도는 막저항(MER)과 이온교환능력(IEC) 변화의 관측으로부터 Py < MP < TMA의 순서로 반응하고 있음을 보여주었다. 한편 SEM image에서는 Py 치환체 막이 가장 균일하고 치밀한 구조를 보여주었으며, 전기화학적 특성에서도 Py이 상용막(AMX)과 비슷한 막저항($5.0{\Omega}{\cdot}cm^2$ >, in 0.5 mol/L NaCl)을 나타내었다. 이 모든 결과로부터 치환체의 공명구조는 균질한 이온교환막의 제조에 기여하고 있음을 알 수 있었다.

• 미생물학회지
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• 제33권3호
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• pp.181-186
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• 1997

유기용매계에서 lipase AK를 사용하여 당 ester화합물을 합성하였다. 유기용매로는 당의 용해도가 높고 반응성이 뛰어난 pyridine을, acyl donor로는 vinyl butyrate을 선택하였다. Transesterification반응에 의해 생성된 monobutyryl fructose와 dibutyryl fructose는 TLC 및 GC 분석으로 확인하였다. Transesterification에 미치는 반응조건은 fructose:vinyl butyrate의 비가 1:10(M/M), 반응온도 40^{\circ}C.$, 교반속도 150rpm, 효소량 10mg/ml의 경우가 적당하였으며 반응시간이 길어질수록 전환율이 높아져, 반응 10일 정도에서 전환율은 90% 이상에 도달하였다. 이때 반응 초기에는 monobutyryl fructose가 주로 합성되었으나 시간이 경과함에 따라 dibutyryl fructose의 함량비가 증가하였다. 반응계에 소량의 수분을 첨가하였을 경우에는 반응속도가 감소함과 동시에 반응산물중 dibutyryl fructose의 양은 줄어들고 monobutyryl fructose의 생성량이 증가하는 경향을 보여주었으며, 수분함량 1%에서는 monobutyryl fructose만이 생성되었다.

• 공업화학
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• 제16권5호
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• pp.705-711
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• 2005

프로테아제인 subtilisin A를 이용하여 유기 용매 안에서 당에스테르인 라우르산부틸에스테르를 합성하였다. 높은 수율을 얻을 수 있기 때문에 유기 용매로는 피리딘이 주로 사용되었으나 냄새가 심하여 식품과 의약품에 사용되는 당에스테르를 합성하는 데에는 적합하지 않다. 그러므로 이를 대체할 유기 용매를 선정하기 위하여 여러 유기 용매 안에서 당에스테르를 효소 합성하였으나 피리딘에 미치지 못하였다. 이에 피리딘을 근거로 하는 W/O 마이크로에멀젼을 만들어 당에스테르를 합성하였는데, Tween 60, Brij 56, 1-O-octyl-${\beta}$-D-glucopyranose과 같은 비이온 계면활성제를 사용하였을 때 수율이 우수하였다.

• Macromolecular Research
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• 제12권1호
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• pp.127-133
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• 2004

We have studied the surface micelle formation of polystyrene-b-poly(2-vinyl pyridine) (PS-b-P2VP) at the air-water interface. A series of four PS-b-P2VPs were synthesized by anionic polymerization, keeping the PS block length constant (28 kg/㏖) and varying the P2VP block length (1, 11, 28, or 59 kg/㏖). The surface pressure-area ($\pi$-A) isotherms were measured and the surface morphology was studied by atomic force microscopy (AFM) after Langmuir-Blodgett film deposition onto silicon wafers. At low surface pressure, the hydrophobic PS blocks aggregate to form pancake-like micelle cores and the hydrophilic P2VP block chains spread on the water surface to form a corona-like monolayer. The surface area occupied by a block copolymer is proportional to the molecular weight of the P2VP block and identical to the surface area occupied by a homo-P2VP. It indicates that the entire surface is covered by the P2VP monolayer and the PS micelle cores lie on the P2VP monolayer. As the surface pressure is increased, the $\pi$-A isotherm shows a transition region where the surface pressure does not change much with the film compression. In this transition region, which displays high compressibility, the P2VP blocks restructure from the monolayer and spread at the air-water interface. After the transition, the Langmuir film becomes much less compressible. In this high-surface-pressure regime, the PS cores cover practically the entire surface area, as observed by AFM and the limiting area of the film. All the diblock copolymers formed circular micelles, except for the block copolymer having a very short P2VP block (1 kg/㏖), which formed large, non-uniform PS aggregates. By mixing with the block copolymer having a longer P2VP block (11 kg/㏖), we observed rod-shaped micelles, which indicates that the morphology of the surfaces micelles can be controlled by adjusting the average composition of block copolymers.