• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1030-1035
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• 2003

The nanoimprint lithography technology makes higher density of semiconductor device and larger capacity of storage media. In this technology the induced damage while detaching polymer pattern from mold should be minimized. In order to analyze the problem, the basic knowledge of adhesion between the polymer and the mold is required. In this study a contact experiment of polyisobutylene specimen with spherical steel tip and polyisobutylene bead tip was conducted using nano indenter. During the contact experiment with various loading rate under load control the contact behavior of viscoelastic material was measured, i.e., the load and displacement between the tip and the specimen were measured. The data was analyzed by HBK model to obtain the stress intensity factor of contact edge and the contact radius as a function of time. Also the adhesion energies between steel/polyisobutylene and polyisobutylene/polyisobutylene were obtained employing the analysis of the crack of viscoelastic material by Schapery.

• Journal of Pharmaceutical Investigation
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• 제19권1호
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• pp.29-37
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• 1989

For the prevention of the aggregation during microencapsulation, the effects and role of polyisobutylene(PIB), as a protective colloid, were studied. The effects of sealant treatment on the microencapsulation were studied. Methyldopa was microencapsulated with ethylcellulose (EC) by polymer deposition from cyclohexane by temperature change using PIB. The EC-microencapsulated methyldopa was sealed with spermaceti. The dissolution of methyldopa was influenced by the drug to wall ratio. When PIB was used, low aggregation of microcapsules occurred and the surface was smooth with a few pores. Treatment of microcapsules with spermaceti retarded the release of methyldopa, the release being affected by the percentage of sealant used and the particle size of the product.

• 한국유변학회:학술대회논문집
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• 한국유변학회 2000년도 춘계 학술발표회 논문집
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• pp.7-10
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• 2000

• 멤브레인
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• 제14권4호
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• pp.275-288
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• 2004

본 연구에서는 준 회분식 교반조를 사용하여 polybutene (PB)와 polyisobutylene (PIB)고분자를 용해한 벤젠 용액을 연속상, 물을 불연속상으로 구성한 w/o 에멀션액막에 $CO_2$을 흡수시켜 흡수속도를 측정하였다. 점탄성을 나타내는 Deborah 수를 사용하여 점탄성 비뉴튼액체에서 구한 부피물질전달계수 ($k_La$)를 고찰하고, 수용액에 첨가한 2-amino-2-methyl-1-propanol(AMP)와 $CO_2$의 반응 메카니즘을 해석하였다.

• 공업화학
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• 제29권3호
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• pp.307-311
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• 2018

중반응성 폴리부텐을 루이스산 촉매를 이용하여 합성하였다. 40~70% 비닐리덴 함량, 수평균 분자량 500~1,000 g/mol, 동점도 20~210 cSt (at $100^{\circ}C$)을 지닌 중반응성 폴리부텐은 노르말프로판올 조촉매와 삼불화붕소 주촉매로 구성된 착물촉매를 사용하여 $-8{\sim}5^{\circ}C$, 2.5 kg 조건에서 가장 좋은 결과로 얻어졌다. 비닐리덴 함량은 반응 온도를 조절하여 쉽게 변화시킬 수 있었다.

• Journal of Pharmaceutical Investigation
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• 제27권4호
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• pp.271-277
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• 1997

Because omeprazole(OMP) is very unstable in aqueous condition, $OMP-{\beta}-CD$, the inclusion complex of OMP and ${\beta}-cyclodextrin({\beta}-CD)$ was made and physicochemical properties of it were compared with those of OMP. Skin permeability of OMP and $OMP-{\beta}-CD$ in propylene glycol vehicle and the reciprocal action of ${\beta}-CD$ with various enhancers were examined through hairless mouse. Adhesive patches were prepared with polyisobutylene and the skin permeability and stability of OMP were investigated. The inclusion complex showed higher solubility and lower partition coefficient than OMP itself. DMSO, 1-methyl 2-pyrrolidone and sodium cholate had an enhancing effect. However ethanol and polysorbate 80 hardly showed the enhancing effect of OMP. When sodium lauryl sulfate and sodium cholate as enhancer were added in patch, the former case showed higher permeability of OMP.

• 약학회지
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• 제43권4호
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• pp.447-457
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• 1999

The purpose of this study is to prepare the adhesive type patch containing flurbiprofen, and to demonstrate the feasibility of flurbiprofen administration through the intact skin using adhesive type patch preparation. For this purpose, two pressure sensitive adhesives, Polyisobutylene(PIB) and $Gelva^{\circledR}737$, were selected from the chemical grade of polymers, and the adhesive type patches of flurbiprofen were prepared. The release rate of flurbiprofen from the PIB-based adhesive patch was higher than that from $Gelva^{\circledR}737$ based adhesive patch. The release rate of flurbiprofen from the PIB-based A-type patch with 1.0mm, 1.5mm or 2.0mm thicknesses followed the first order kinetics. In the skin permeation study, using male hairless mouse skin, a monophasic skin permeation profile was observed with 1% flurbiprofen loading dose. The inclusion of palmitic acid or SLS(0.25~0.5%) as an enhancer produced a remarkable enhancement in the skin permeation rate of flurbiprofen, and the percentile ratio of drug and enhancer appeared to be important for the effective enhancement. In the in vivo percutaneous absorption study, the plasma concentration of the optimal formulation was significantly (p<0.01) higher than that of the conventional cataplasma ($Bifen^{\circledR}$). These studies demonstrate a good feasibility of flurbiprofen administration through the intact skin using a transdermal patch, and show a possibility of the development of flurbiprofen patches.

• Journal of Pharmaceutical Investigation
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• 제29권4호
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• pp.343-348
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• 1999

The purpose of this study is to prepare the controlled release adhesive patch containing naproxen. Pressuresensitive adhesive (PSA)-type patch was fabricated by casting of polyisobutylene (PIE.) and mineral oil in toluene. Membrane-controlled release (MCR)-type patch was prepared by the attachment of the controlled release membrane on the PSAtype patch. The membrane was mainly composed of Eudragit, polyethylene glycol(PEG) and glycerin. The drug release profile and skin permeation test with various patches were evaluated in vitro. The release of naproxen from PIE-based PSAtype patch with various loading doses fitted Higuchi's diffusion equation. However, the permeation of naproxen through hairless mouse skin from PSA-type patch followed zero-order kinetics. In MCR-type patch, thickness of controlled release membrane affected on the drug release rate highly. In the composition of membrane, the release rate was decreased as the ratio of Eudragit increased. The drug release from the MCR-type patch followed zero order kinetics. The permeation of naproxen through hairless mouse skin from MCR-type patch showed lag time for the intial release period and didn't fit the zero-order kinetics

• 멤브레인
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• 제10권1호
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• pp.19-29
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• 2000

고분자/용매계에서 물질전달현상에 이용되는 용매의 상호확산계수를 예측하기 위하여 기존의 UNFACFV을 적용한 확산식을 유도하였으며, 상호확산계수를 계산하였다. 또한, 새로운 모델식에 의하여 계산한 값을 실험치 및 Vrentas-Duda의 이론치와 비교하였다. 상화확산계수를 구하는데 필요한 자기확산계수는 Vrentas-Duda의 이론을 이용하고, 용매의 화학포텐셜의 농도 미분항은 original UNIFAC-FA와 modified UNIFAC-FV를 사용하였다. Flory-Hugginstlr을 이용한 Vrentas-Duda의 상호확산식은 용매의 화학포텐셜의 농도 미분항을 표현하기 위하여 매개변수 x를 온도와 농도에 무관한 상수로 가정한 단점을 가지고 있으나, 본 연구에서 제시한 방법에서는 이러한 가정이 없으며, 여러 가지 고분자/용매계(polyisobutylene homopolymer 및 polyisobutylene-poly(pmethylstyrene) copolymer와 cyclohexane, n-hexane, n-pentane, chloroform, toluene)에서의 상호확산계수를 잘예측하였다. 특히 PIB/toluene계의 경우, 본 논문에서 사용된 방법이 Vrentas-Duda 이론에 의한 것보다 실험치에 더 가까웠다. 또한, 아무런 가정이나 제약없이, 넓은 온도 및 농도 영역에서 고분자/용매계의 상호확산계수를 예측할 수 있는 좋은 방법임을 알 수 있었다.

• 한국식품과학회지
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• 제39권2호
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• pp.158-163
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• 2007

본 연구는 curdlan 복합필름을 제조하고 물성을 비교하기 위해 수행되었다. 우선 low set 방식과 high set 방식 중 적절한 방식을 선정하였고, 순차적으로 AMG나 oleic acid 중에서 적절한 방습소재를 선정하였으며, PB와 PIB 중에서 적절한 물성개량제를 선정하고자 하였다. 그 결과 high set 필름이 low set 필름보다 신장율은 다소 작지만 인장강도가 높고 수증기 투과도가 낮기 때문에 curdlan 복합필름 제조에는 high set 방법이 더 적합하며 이때 PEG는 2.0g 첨가하는 것이 유리할 것으로 판단하였다. 또한 oleic acid 첨가군이 AMG 첨가군보다 인장강도와 신장율이 더 크고, 수증기투과도는 더 낮은 편이며 특히 oleic acid 0.3g 첨가한 경우 신장율과 수증기 차단성 면에서 유리하므로 방습소재로서 oleic acid를 0.3g 첨가하는 것이 적합할 것을 판단하였다. PIB 첨가군이나 PB 첨가군 모두 인장강도와 수증기투과도는 비슷하나 신장율의 경우는 PIB 첨가군이 PB 첨가군보다 더 큰 것으로 나타났으므로 유연성과 관련된 물성개량 측면에서는 PIB 첨가가 더 유리할 것으로 판단하였다. 종합적으로 curdlan에 가소제 PEG와 방습소재 oleic acid와 물성개량제 PIB를 첨가하는 것이 유연성과 관련된 물성 면에서 가장 유리할 것으로 판단하였다.