• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 NEW STRATEGY FOR DRUG DEVELOPMENT IN POST-GENOMIC ERA(대한약학회)
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• pp.159.2-160
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• 2000

• 한국연초학회지
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• 제27권1호
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• pp.68-74
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• 2005

Glycerol triacetate(triacetin) is the currently used common plasticizer in the making filters from cellulose acetate tow. For the mono acetate filter, the determination of triacetin contents is already established by CORESTA recommended method (No. 59). But unfortunately, the analytical method of triacetin in the activated carbon filter have not reported so far. In this study, it was established the analytical method of carbon filter's triacetin contents at various extraction conditions, bath ratio and internal standard materials. The confidential level appeared above $95\%$ when the extraction time, ISTD material and bath ratio was 3 hours, tripropionin and below 500 mg activated carbon / 50 $m\ell$ ethanol, respectively. Also, in the distribution of triacetin with filter materials in activated carbon filters, the triacetin amount was the most contained in activated carbon. Therefore, this method can be applied to the determination of triacetin contents in the activated carbon filter.

• 한국산학기술학회논문지
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• 제16권1호
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• pp.914-920
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• 2015

본 논문에서는 PLA(PolyLactic Acid)의 결정화도 및 결정구조에 대해 연구하였다. PLA는 옥수수 전분으로부터 추출한 Lactic acid로부터 얻어지는 친환경적인 열가소성 플라스틱으로 매립시 미생물에 의해 완전히 분해되는 소재로 각광받고 있지만 열 안정성이 낮고 낮은 결정화도로 인해 높은 기계적 물성이 요구되는 용도에는 부적합한 단점을 가지고 있다. 이 중에서도 낮은 결정화도와 느린 결정화 속도는 사출 성형 공정에서 Cycle time을 증가시키는 요인으로 다른 소재와의 경쟁에 매우 큰 단점으로 나타난다. 본 논문에서는 핵제 및 가소제의 종류와 함량에 따른 결정화도 및 결정화 속도의 변화를 연구함으로써 궁극적으로 사출 성형 공정에서 Cycle time을 개선하고자 하였다.

• 공업화학
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• 제9권7호
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• pp.979-984
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• 1998

Nylon6,6를 matrix로 사용하여 전도성 고분자인 polyaniline(PANI)과의 전도성 복합체를 블렌딩 방법에 의하여 제조하였다. 블렌딩은 m-cresol를 용매로 사용하였으며 PANI는 camphorsulfonic acid(CSA) 혹은 dodecylbenzenesulfonic acid (DBSA)와 같은 알킬 벤젠 술폰산으로 양성화시켰다. 또한, 비상용성인 두 고분자간의 혼화성을 개선시키기 위하여 가소제를 첨가하여 상분리를 최대한 억제시켰다. 제조된 전도성 복합체에 대하여 양성화제의 유무에 따라 또는 PANI의 함량에 따라 전기전도도 및 몰포로지 등을 측정 분석하였다. PANI 착체의 함량이 증가할수록 전기전도도는 증가하였고, 알킬 사슬의 길이가 긴 DBSA로 양성화된 PANI(25wt%)과 가소화된 nylon6,6의 전도성 복합체의 전기전도도는 1.02 S/cm까지 향상되었다.

• 분석과학
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• 제10권6호
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• pp.453-458
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• 1997

poly(vinyl chloride)와 가소제만으로 된 막을 제조하여 몇 가지 염기성 의약품에 대한 감응 특성을 조사하여 보았다. 감응막을 초기의 전위값으로 빨리 되돌리기 위하여 황산으로 처리하였다. chlorpromazine을 정량할 때 2-nitrophenyl octyl ether을 사용한 막에서 $10^{-6}{\sim}10^{-3}M$, dioctyl PhenylPhosphnate, isododecyl phenylphosphate, dioctyl maleate 등의 경우 $10^{-6}{\sim}10^{-2}M$까지의 직선성 검량선을 얻을 수 있었고, 항생제, 당, 그리고 1급 아민화합물에 대한 감응선은 적게 나타났다.

• 한국분말재료학회지
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• 제24권2호
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• pp.147-152
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• 2017

Spherical-type zirconia granules are successfully fabricated by a spray-drying process using a water solvent slurry, and the change in the green density of the granule powder compacts is examined according to the organic polymers used. Two organic binders, polyvinyl alcohol (PVA) and 2-hydroxyethyl methacrylate (HEMA), which are dissolved in a water solvent and have different degrees of polymerization, are applied to the slurry with a plasticizer (polyethylene glycol). The granules employing a binder with a higher degree of polymerization (PVA) are not broken under a uniaxial press; consequently, they exhibit a poor green density of $2.4g/cm^3$. In contrast, the granule powder compacts employing a binder with a lower degree of polymerization (HEMA) show a higher density of $2.6g/cm^3$ with an increase in plasticizer content. The packing behavior of the granule powders for each organic polymer system is studied by examining the microstructure of the fracture surface at different applied pressures.

• Fibers and Polymers
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• 제7권2호
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• pp.89-94
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• 2006

Ionic conductivity and mechanical properties of a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresin type M (CRM) with various lithium salts and plasticizer were examined. The CRM used was a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) with a molar ratio of 1:1, mixed plasticizer was ethylene carbonate (EC) and propylene carbonate (PC) at a volume ratio of 1:1. The conductive behavior of polymer electrolytes in the temperature range of $298{\sim}338\;K$ was investigated. The $PEG/LiClO_4$ complexes exhibited the highest ionic conductivity of ${\sim}10^{-5}S/cm$ at $25^{\circ}C$ with the salt concentration of 1.5 M. In addition, the plasticized $PEG/LiClO_4$ complexes exhibited improvement of ionic conductivity. However, their complexes showed decreased mechanical properties. The improvement of ionic conductivity and mechanical properties could be obtained from the polymer electrolytes by using CRM. The highest ionic conductivity of PEG/CRM/$LiClO_4$/(EC-PC) was $5.33{\time}10^{-4}S/cm$ at $25^{\circ}C$.

• 한국신뢰성학회지:신뢰성응용연구
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• 제13권2호
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• pp.141-151
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• 2013

The study of environmental stress cracking (ESC) by contact with plastic rulers and PVC erasers which was artificially added to the external stress was carried out in order to accelerate the chemicals crack. To analyze a blooming plasticizer that migrates from the inside of blended eraser to the surface of the eraser, the ESC experiments were carried out at room temperature and $50^{\circ}C$ conditions. The chemicals crack shape caused by the plasticizer and the brittle fracture shape resulted from the external stress were observed in consequence with the cross-sectional surface analysis of the ruler crack by the ESC. The bending strength of the plastic rulers were fractured prior to the yield point and it had low bending flexure stress. We presented that ESC of polymer materials was affected by the polarity of the chemicals and polymer, the exposure time to chemicals, the exposure temperature and the level of strain on the polymer.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.3088-3092
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• 2013

A novel PVC membrane sensor for perindopril based on perindopril-phosphotungstate ion pair complex was prepared. The influence of membrane composition (i.e. percent of PVC, plasticizer, ion-pair complex, and kind of plasticizer), inner solution, pH of test solution and foreign cations on the electrode performance was investigated. The optimized membrane demonstrates Nernstian response ($30.9{\pm}1.0$ mV per decade) for perindopril cations over a wide linear range from $9.0{\times}10^{-7}$ to $1{\times}10^{-2}$ M at $25^{\circ}C$. The potentiometric response is independent of the pH in the range of 4.0-9.5. The proposed sensor has the advantages of easy preparation, fast response time. The selectivity coefficients indicate excellent selectivity for perindopril over many common cations (e.g., $Na^+$, $K^+$, $Mg^{2+}$, $Cu^{2+}$, $Ni^{2+}$, rhamnose, maltose, glycine and benzamide. The practical applications of this electrode was demonstrated by measuring the concentrations of perindopril in pure solutions and pharmaceutical preparations with satisfactory results.

• Journal of Pharmaceutical Investigation
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• 제38권6호
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• pp.381-385
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• 2008

Isosorbide dinitrate is an oral assiatant therapy agent of angina pectoris, myocardial infarction and congestive heart failure. The objective of this study was to formulate sustained release containing isosorbide dinitrate and assess their formulation variables. Pellets were prepared by fluid bed process and consist of drug layer and membrane layer. The pellets were coated with ethylcellulose along with $5{\sim}15%$ of plasticizer such as triacetin and diethyl butylrate. In vitro evaluation study was performed by comparative dissolution test between test and reference isosorbide dinitrate preparation. We could prepare sustained pellets of isosorbide dinitrate by fluid bed process which were reduced process time and had high content. The pellet coated with 1% ethylcellulose and triacetin(l5%) had a similar dissolution behavior compare to reference isosorbide dinitrate preparation controlling initial dissolution and those of dissolution at 30 min were 17.25 and 17.09%, respectively. Difference factor and similarity factor were $0{\sim}15$ and $50{\sim}100$ and there was no significant difference in bioequivalence between formulations. It might be concluded that our sustained release pellet of isosorbide dinitrate could be an alternatively delivery system to reference drug preparation.