• Food Science and Preservation
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• v.16 no.2
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• pp.139-146
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• 2009

Whole and stem-off cherry tomatoes were packaged using perforated films(LF05, LF10, LF20, and LF40). Gas composition(ethylene, $O_2$, and $CO_2$), firmness(compression and penetration force), color, brix degree, acidity, and total microbial counts were assessed during storage at $10^{\circ}C$ and 85% relative humidity. Gas composition varied with film gas permeability, indicating that modified atmospheric(MA) conditions were achieved. Firmness fell during storage; samples packed using LF05 showed the lowest firmness, corresponding to low gas transmission conditions. L(lightness) and a(redness) values respectively decreased and rose slightly with increasing storage time, but the b(yellowness) values fell notably. Film permeability significantly affected acidity and soluble solid levels. When LF40 packaging was used, acidity and brix scale changes were similar to those seen after PET container packaging. Total microbial counts increased with time after packaging in most films, and pretreatment differences were not significant. Microflora varied between stem on/off tomatoes. Skin wrinkling and juice appearance were common in tomatoes stored in PET containers and LF films of low gas permeabilities(LF05, LF10, and LF20). White molds were partially found on stem-on tomatoes stored using packaging systems. When film packagings were compared, LF40 was optimal, permitting minimal pretreatment yet offering maximal sanitation.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.5 no.2
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• pp.9-16
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• 1999

Edible films were prepared from proteins extracted from soybean curd residue by alkaline extraction and isoelectric precipitation. Effects of film forming solution pH and plasticizers on mechanical and barrier properties of edible films were studied. films were formed within pH $7{\sim}11$ with tensile strength (TS) of $2.9{\sim}3.3$ MPa. Films produced under pH 10 had the highest TS and Elongation (E) (3.3 MPa and 60.1%) but no significant difference was observed among water vapor permeabilities (WVP) of film. Glycerol, sorbitol and its mixture (1:1, w/w) were added as plasticizers. The concentration and mixing ratio of plasticizers also affected the TS, E and WVP of films. TS of films decreased from 15.0 MPa to 2.9 MPa as plasticizer concentration increased from 0.4 to 0.8 g plasticizer/g protein. At a plasticizer concentration, the highest TS was observed when sorbitol was used whereas the highest E was measured when mixture of glycerol and sorbitol was used as plasticizer WVP of films increased as the plasticizer concentration increased. Films plasticized with glycerol showed the highest WVP among the films with the same plasticizer concentrations. Edible films prepared from soybean curd residue protein showed very low oxygen permeabilities ($29.5{\sim}61.1aL{\cdot}m/m^2{\cdot}s{\cdot}Pa$) and oil resistance at all plasticizer concentration level tested.

• Membrane Journal
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• v.20 no.2
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• pp.106-112
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• 2010

This study deals with the surface fluorination of poly(phenylene oxide) (PPO) with the direct contact of 100 ppm fluorine gas. To characterize the surface fluorinated membranes, the contac angle measurement, X-ray photoelectron microscopy analysis and the gas permeation experiments were performed. As the fluorination time increases, the hydrophobicity of membrane surfaces is increased by the surface characterization. In general, as expected, the overall gas permeability was reduced. Typically, the permeability reduction of 33% for nitrogen, 23% for oxygen and 3% for carbon dioxide were observed when the membranes were exposed in 100 ppm environment for 60 min., meanwhile the selectivity was increased from 3.92 to 4.47 for $O_2/N_2$ and 18.09 to 25.4 for $O_2/N_2$, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.269-270
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• 2006

이온빔 스퍼터를 사용하여 PC기판위에 $TiO_2$ 박막을 증착한 후 광학적 특성을 고찰하였다. 증착 전 어시스트 이온건을 사용하여 아르곤 플라즈마로 표면처리를 하였으며, Ti 박막을 $300{\AA}$정도로 증착한 다음, 그 위에 산소 반응스퍼터링 기법을 사용함으로써 $TiO_2$박막을 증착하였다. 표면처리에 의한 기판의 표면개질로 TI 버퍼층과의 막부착력을 높이고, 아르곤 산소의 분압비를 1로 고정하였을 때, $TiO_2$박막의 두께에 따라서 박막의 색상이 변화는 것을 관찰할 수 있었다. 또한, 아르곤과 산소의 분압 변화에 대한 의존성은 $TiO_2$박막의 색상과 투과율과 같은 광학적인 성질에 영향을 미치는 것을 알 수 있었다.

• Polymer(Korea)
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• v.35 no.5
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• pp.402-408
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• 2011

To improve $Na^+$-saponite(SPT) film flexibility, we prepared SPT hybrid clay films with various poly(vinyl alcohol) (PVA) concentrations(0~10 wt%) using the solution intercalation method. In this study, we investigated the thermo-optical properties, morphology, and gas permeability of the SPT hybrid films. We also examined the relationship between the film properties and PVA content using wide angle X-ray diffraction measurements(XRD), field emission scanning electron microscopy(FESEM), differential scanning calorimetry(DSC), thermogravimetric analysis(TGA), thermomechanical analysis(TMA), ultraviolet-visible(UV-vis) spectroscopy, and oxygen transmission rate($O_2$TR) testing. The properties of the clay hybrid films were strongly affected by PVA filler content. The presence of a small amount of PVA was sufficient to improve the flexibility of SPT hybrid films.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.36-39
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• 1998

플루란은 글루코스 삼량체인 말토트리오스(maltotiose)를 반복단위로 하고, 그 삼량체와는 다른 결합인 $\alpha$-1,6결합에 의해 반복결합한 고분자 선상 중합체이다(Fig. 1) 플루란은 검정색 효모인 aureobasidium pullulans에 의해 배양 생산된 천연 다당류의 일종이다. 플루란은 원료가 저렴하기도 하지만 플루란으로 만들어진 막, 필름(1), 섬유(2) 등의 일반적인 성형물은 투명성, 강인성, 산소 불투과성이 있으며 땅속 수중에서 자연 분해되며 소각에 의해 유독가스와 고엽이 발생하지 않으므로 공해를 동반하지 않는다.(중략)

• Journal of the Korean Vacuum Society
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• v.9 no.4
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• pp.411-418
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• 2000

$Al_2O_3$ thin films of 300 nm thickness were deposited at room temperature using DC reactive sputtering with variation of the $O_2$ content in the sputtering gas from 30% to 70%. Regardless of the $O_2$ content in the sputtering gas, the sputtered $Al_2O_3$ films were amorphous and exhibited the refractive index of 1.58. When the $O_2$ content in the sputtering gas was higher than 50%, the $Al_2O_3$ films exhibited excellent transmittance of about 98% at 550 nm wavelength. However, the transmittance decreased to about 94% for the $Al_2O_3$ films deposited with the sputtering gas of the 30% and 40% $O_2$contents. The optimum dielectric properties (dielectric constant of 10.9 and loss tangent of 0.01) was obtained for the $Al_2O_3$ film deposited with the sputtering gas of the 50% $O_2$ content. When the $O_2$ content in the sputtering gas was within 40% to 60%, the $Al_2O_3$ films exhibited no shift of flatband voltage $V_{FB}$ in C-V curves and exhibited leakage current density lower than $10^{-5}\textrm{A/cm}^2$ at 150 kV/cm.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.761-765
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• 2010

Poly (N,N-dimethylacrylamide) is very useful in various fields due to its remarkable properties, such as water solubility and biocompatibility. This study used N,N-dimethylacrylamide with the cross-linker EGDMA (ethylene glycol dimethacrylate), HEMA (2-hydroxyethyl methacrylate), MMA (methyl methacrylate), NVP (N-vinyl-2-pyrrolidone) and the initiator AIBN (azobisisobutyronitrile) for copolymerization. Measurement of the physical properties of the copolymerized polymer showed that the water content was 36 - 42%, refractive index was 1.433 - 1.426 and visible ray transmittance 90 - 91% while the oxygen permeability showed a distribution between 13.1 and $21.29{\times}10^{-11}(cm^2/sec)$ ($mlO_2/mL{\times}mmHg$). The measurement showed that the increased amount of oxygen permeability of the copolymer measured using the polarographic method range between 11.0% and 80.5%. Based on the results of this study, the produced copolymer is suitable for use as a material to high oxygen permeability hydrogel lenses.

• Analytical Science and Technology
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• v.7 no.3
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• pp.371-378
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• 1994

The detection range of this galvanic oxygen sensor for oxygen concentration was 0.0% to 20.0%. By using gold or silver as cathode, reproducible response time and sensitivity to change of oxygen concentration were observed. The anode was Pb-Sn-Ca alloy. Oxygen selective permeable membrane was hydrophobic and porous Teflon film. The effect of the membranes varying in thickness have been studied on the temperature($10{\sim}50^{\circ}C$) and relative humidity(R. H 0~99%). Lead acetate buffer solution as the electrolyte has shown a high output voltage and longer life.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.158-158
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• 1999

NiO 박막은 전자비임증착법과 RF-스퍼터링법으로 제작하여 박막의 성능을 평가하였다. NiO 박막의 성능평가를 위한 착색과 탈색은 전기적 착색셀을 제작하여 순환전압전류법으로 KOH 전해질 내에서 반복수행하였으며 성능이 퇴화된 박막의 투과율은 가시광선 분광기로 측정하였다. XPS에 의한 분석결과 막의 낱알 내부보다 낱알 표면에 많은 산소가 포함될수 있음을 알 수 있었다. KOH 전해질 속에서 사이클이 반복 수행된 막의 표면 낱알의 형태는 변하였으며, 3$\times$10-4mbar에서 제작된 시료가 막의 안정성이 좋았다. 제작 방법에 다라 막에 주입 및 추출되는 전하밀도와 투과율의 차이가 나타났고, 니켈 산화물 박막의 성능평가를 하기 위해 착색효율을 계산하였다. 기판물질인 IT(indium tin oxide)의 전기적 착색성과 전해질이 전기적 착색성에 미치는 영향에 대해서도 논의되었다.