• Electrical & Electronic Materials
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• v.5 no.2
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• pp.244-251
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• 1992

무독성 혼합안정제 Zn/Ca-stearate의 방사선 안정화 효과를 증진시키기 위해서 oxy-methylene, oxy-ethylene 및 oxy-porpylene 구조의 직쇄형 및 고리형 에테르 화합물을 PVC에 배합하여 방사선조사 하였을 때 PVC의 색차변화를 측정하여 이들 에테르 화합물의 방사선 안정화 효과를 비교 검토하였다. 에테르 화합물에서 oxy-ethylene 구조단위수 4이상인 직쇄형 에테르 또는 고리형 에테르와 oxy-propylene 구조단위수 7인 직쇄형 에테르는 매우 우수한 방사선 안정화 효과를 나타내고 있다. oxy-ethylene 또는 oxy-propylene 구조의 에테르의 방사선 안정화는 Zn/Ca-stearate에서 생성되는 ZnCl$_{2}$와 에테르의 주쇄구조 oxy-ethylene 또는 oxy-propylene의 착체반응에 의한 것으로 추정된다.

• Bulletin of the Korean Chemical Society
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• v.24 no.10
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• pp.1485-1489
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• 2003

The gelation for di-(2-ethylhexyl) phthalate (DEHP)-plasticized poly(vinyl chloride) was studied by measuring time-resolved small-angle X-ray scattering (SAXS) and a flow of the solutions in test tube. It was found that for the gelation there were three regimes. At Regime I, the solution rapidly changed to a gel, and the SAXS intensity showed a peak and the peak intensity increased, keeping the peak angle constant. Applying the SAXS intensity to the kinetic analysis of the liquid-liquid phase separation, it was revealed that the spinodal decomposition proceeded to develop a periodic length of 29.9 nanometer in size, a hydrogen-bonding-type association in polymer rich phase followed, and then it induced fast gelation rate. At Regime II, the gelation slowly occurred and the SAXS intensity was not observed, suggesting that a homogeneous gel network was formed by a hydrogen-bonding. At regime III, the solution was a homogeneous sol.

• Journal of the Korean Chemical Society
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• v.42 no.5
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• pp.531-538
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• 1998

The ion selective membrane electrode made of calix[4]arene-based host 1 as ionophore, poly (vinyl chloride) (PVC) as matrix and dioctylsebacate (DOS) as a plasticizer was studied. The potential responses of this membrane electrode to alkali, alkaline earth and transition metal cations were investigated. Especially this membrane electrode was turned out to be affinitive for $Pb^{2+}$ in the deionized water. It was observed that the response was linear in the concentration range from $1.0 \times 10^{-1} M to 1.0 \times 10^{-6} M of Pb^{2+}$ and its slope (26.5 mV/decade) was near to the sub-Nernstian response in deionized water. Also, the potential was maintained constantly in the range of pH $4.00 \sim 12.00$, which supports the potential usage as $Pb^{2+}$ affinitive electrode in the deionized water.

• Korean Membrane Journal
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• v.5 no.1
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• pp.36-42
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• 2003

A Prediction of pervaporation performance was studied by solubility parameter calculation approach for the benzene/cyclohexane mixture system using rubbery blend membrane with various solubility parameters. The solubility parameter of the rubbery blend membranes were controlled with different blend ratio of the poly(acrylonitrile-co-butadiene), poly(styrene-co-butadiene) and poly(vinyl chloride). Screening of blend formulations was accomplished by simple swelling tests. When the content of NBR is increased, the swelling of both benzene and cyclohexane are decreased. However, the ratio of benzene swelling to swelling by cyclohexane (the swelling selectivity) increases. The same is true for blends in which the PVC content is increased. Adoption of a solubility parameter calculation provides an a priori methodology for seeking the best blend formulation.

• YAKHAK HOEJI
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• v.43 no.3
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• pp.289-293
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• 1999

Many poly (vinyl chloride : PVC) membrane electrodes were investigated for the determination of basic drugs, chlorpromazine, amitriptyline, nortriptyline, etc. These electrodes are based on the use of the ion-association complexes of the basic drugs with eriochrome cyanine R, chromoxane cyanine, chrome azurol S and picric acid as ion-exchange sites in a plasticized PVC matrix. All ion-exchangers except picrate complex were not proper for use, because those complexes in plasticized membrane were excluded into aqueous working solution. These drug electrodes show excellent Nernstian responses in the concentration ranges $10^{-2}~10^{-6}$ mol $dm^{-3}$. Their selectivity with respect to each other, as well as their work-able pH range have been investigated. The major advantages of the proposed methods are their simplicity and speed.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.9-12
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• 2001

Blending is an easy and popular means to achieve a desired set of characteristic properties. The blends, by melt mixing of thermoplastic materials and elastomer, have received considerable attention in recent years. It is well known that nearly all blends comprise one polymer domain dispersed in the matrices of the other polymer [1]. (omitted)

• YAKHAK HOEJI
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• v.44 no.5
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• pp.406-410
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• 2000

The present method is to describe a potentiometric norfloxacin electrode system characterized by a membrane, based on the use of norfloxacin (NF) complex with ion-association reagents. These complexes were dissolved in DMSO, DMF acetonitrile or acetone and dispersed in plasticized poly(vinyl chloride) matrix. The picric acid complex electrode exhibited near-Nernstian response for NF in acetate buffer solution (pH 4.0) with a slope of 53.03 mV/decade. And linear response over the range of 10$^{-5}$ to 10$^{-3}$M solution of NE. The ingredients in tablet, capsule and biological important organic acids were not interfere.

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.37-44
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• 2003

We examined the effect of polyether-type nonionic surfactants (Brij 35, Triton X-100, Tween 20 and Tween 80) on the potentiometric properties of sodium-, potassium- and calcium-selective membranes which are prepared with widely used ionophores and four kinds of polymer matrices [poly(vinyl chloride) (PVC), polyurethane (PU), PVC/PU blend, and silicone rubber (SR)]. It was found that the PVC-based membranes, which provide the best performance among all other matrix-based membranes in the absence of nonionic surfactants, exhibited larger change in their potentiometric properties when nonionic surfactants are added to the sample solution. On the other hand, the sodium-selective SR-based membrane with calix[4]arene, potassium-selective PVC/PU- or SR-based membrane with valinomycin, and the calcium-selective SR-based membrane with ETH 1001 provide almost identical analytical performance in the presence and absence of Tween 20 or Tween 80 surfactants. The origin of nonionic surfactants effect was also investigated by interpreting the experimental results obtained with various matrices and ionophores. The results suggest that the nonionic surfactant extracted into the membrane phase unselectively form complexes with the primary and interfering ions, resulting in increased background potential and lower binding ability for the ionophore. Such effects should result in deteriorated detection limits, reduced response slopes and lower selectivity for the primary ions.

• Journal of the Korean Chemical Society
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• v.29 no.3
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• pp.319-327
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• 1985

The effect of titanate coupling agents on the electrical and mechanical properties of conductive poly (vinyl chloride)-nickel composite was studied as functions of filler concentration, the variation of the amount of titanate coupling agents and the type of titanate coupling agents. It was found that the electrical and mechanical properties of PVC-Ni system were improved by the treatment of titanate coupling agents, but the excessive use of titanate coupling agents influenced to give worse properties.

• Analytical Science and Technology
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• v.11 no.4
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• pp.235-242
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• 1998

Membrane electrode based on chitin(po1y-[$1{\rightarrow}4$]-${\beta}$-N-acetyl-D-glucosamine) was prepared by mixing uniformly grounded of chitin (100 mesh) with PVC and DOS. We investigated the potential response of chitin membrane electrode to metal ions. It was observed that the response slopes for $Cd^{2+}$(34.9 mV/decade) and $Cu^{2+}$(34.0 mV/decade) were larger than those for other ions in pH 4 acetate buffer. The potentiometric response of chitin electrode to varying pH was nearly constant in the pH range of 2~12.