• 한국의류산업학회지
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• 제19권4호
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• pp.493-503
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• 2017

This study investigated water vapor permeability of the 73 breathable fabrics for sports-wear according to the materials, finishing methods and fabric structural parameters. The water vapor permeability by KS K 0594 method of PET breathable fabric was superior than that of nylon one, in addition, water vapor permeability of coated or laminated breathable fabrics were higher than those of hot melt or dot laminated fabrics. The water vapor permeability of breathable fabric was dependent on the thickness, weight and density, which was consistent with measuring method. However, water vapor permeability according to materials and finishing method showed different results according to measuring method. The correlation coefficient of WVP of PET breathable fabrics between ISO and KS K measuring methods was -0.83 and the correlation coefficient of WVP of coated breathable fabrics was -0.72 and -0.71 for KS K and ASTM and -0.72 for KS K and ISO in hot melt laminated breathable fabrics. According to regression analysis, WVP of PET breathable fabric by both KSK and ISO measuring methods was highly dependent upon on the density and weight. In addition, WVP of hot melt laminated breathable fabric was highly dependent upon thickness, weight and density. Therefore, relevant measuring method for WVP of breathable fabrics has to be adopted to measure precise breathability.

• Macromolecular Research
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• 제17권7호
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• pp.528-532
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• 2009

The size and shape of free volume (FV) holes available in membrane materials control the rate of gas diffusion and its permeability. Based on this principle, a segmented, thermo-sensitive polyurethane (TSPU) membrane with functional gate, i.e., the ability to sense and respond to external thermo-stimuli, was synthesized. This smart membrane exhibited close-open characteristics to the size of the FV hole and water vapor permeation and thus can be used as smart food packaging materials. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), positron annihilation lifetimes (PAL) and water vapor permeability (WVP) were used to evaluate how the morphological structure of TSPU and the temperature influence the FV holes size. In DSC and DMA studies, TSPU with a crystalline transition reversible phase showed an obvious phase-separated structure and a phase transition temperature at $53^{\circ}C$ (defined as the switch temperature and used as a functional gate). Moreover, the switch temperature ($T_s$) and the thermal-sensitivity of TSPU remained available after two or three thermal cyclic processes. The PAL study indicated that the FV hole size of TSPU is closely related to the $T_s$. When the temperature varied cyclically from $T_s-10{\circ}C$ to $T_s+10^{\circ}C$, the average radius (R) of the FV holes of the TSPU membrane also shifted cyclically from 0.23 to 0.467 nm, exhibiting an "open-close" feature. As a result, the WVP of the TSPU membrane also shifted cyclically from 4.30 to $8.58\;kg/m^2{\cdot}d$, which produced an "increase-decrease" response to the thermo-stimuli. This phase transition accompanying significant changes in the FV hole size and WVP can be used to develop "smart materials" with functional gates and controllable water vapor permeation, which support the possible applications of TSPU for food packaging.

• Food Science and Biotechnology
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• 제14권1호
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• pp.108-111
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• 2005

To improve water-resistance and physical properties of sodium alginate film, effects of sodium alginate and plasticizer concentrations, divalent cation types and concentrations, and immersion time of films into divalent cation solutions on sodium alginate films were evaluated, based on elongation strength (ES), elongation rate (E), water vapor permeability (WVP), and water solubility (WS). Film made from 1.5% sodium alginate solution (w/w) had low WVP and WS, which are optimal characteristics for application of film preparation. Addition of plasticizer increased E and WS. Less than 2% $CaCl_2$ addition and 15min immersion time reduced WVP, WS, and E significantly (p<0.05). Sodium alginate films treated with $CuCl_2$, and $ZnCl_2$ solutions had lower WVP and WS, whereas $MgCl_2$ had no influence on improving water resistance of films.

• Biotechnology and Bioprocess Engineering:BBE
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• 제2권2호
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• pp.122-125
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• 1997

The utilization of excess whey is necessary to reduce dairy waste because the large amount of whey disposal in waste streams has caused environmental problems. During whey protein film production as the effective means of utilization of excess whey, we have examined the effects of pH, temperature, and plasticizers for water vapor permeability(WVP), tensile strength(TS), and elongation rate(%E) of the whey protein films. The 10% whey protein films had the highest WVP(28.73g$.$mm/kPa$.$day$.$㎡) and TS(1.85${\pm}$0.11Mpa). But, in this case, an increase of WVP was caused by the thickness of whey protein films. At the concentration of 8% whey protein, appropriate thickness was obtained. Whey protein films prepared at the pH 6.75 and 95$^{\circ}C$ showed lower WVP(28.38g$.$mm/kPa$.$day$.$㎡) and elongation rate(12.9%) and higher TS value(3.769${\pm}$0.407 MPa) than at the pH 6.75 and 75$^{\circ}C$. As the temperature increased, WVP of films decreased slightly and tensile strength increased slightly, while elongation rate decreased significantly. Higher WVP and TS were observed at pH6.75 compared to pH7-9. In contrast, significantly higher elongation was observed at pH 9comapred to pH6.75-8. Among the plasticizer types used, the addition of sorbitol showed the highest TS value(6.244${\pm}$0.297 MPa) at the concentration 0.4g sorbitol and elongation rate(49%) at the concentration of 0.6g sorbitol.

• 한국수산과학회지
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• 제33권5호
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• pp.413-417
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• 2000

생분해성이면서 가식성인 어분 단백질필름 제조를 목적으로 필름의 가공조건이 단백질필름의 성질에 미치는 영향을 밝히기 위하여 명태어분으로부터 단백질을 추출하고, 가공조건을 달리하여 제조한 필름의 수증기 투과도와 용해도의 변화를 측정한 결과는 다음과 같다. APMPI 필름의 수증기 투과도는 가소제 glycerol의 첨가량이 증가함에 따라 증가였으나, pH 7 이상에서는 pH의 증가에 따라 감소하였다. 필름단백질의 용해도는 pH 및 가소제의 농도가 증가함에 따라 감소하였다. 필름의 총용해량은 가소제의 농도가 증가함에 따라 증가하였으나 pH가 증가할수록 감소하였다 가소제의 종류를 달리하여 필름을 제조할 때 수증기 투과도는 glycerol, polyethylene glycol 및 sorbitol 첨가 필름의 차례로 높게 나타났다. 또한 총용해량은 반대의 순서를 나타내었다.

• 한국식품영양과학회지
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• 제46권3호
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• pp.394-399
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• 2017

플라스틱 포장 폐기물로 인한 환경오염을 해결하기 위한 대안으로 생분해성 필름이 많이 연구되어 왔다. 본 연구에서는 우럭 껍질 젤라틴(RFG)과 nano-clay(Cloisite $Na^+$, 10A)의 복합필름의 특성에 관하여 연구하였다. 우럭 껍질로부터 젤라틴을 추출하여 sorbitol을 가소제로서 첨가한 단백질 필름을 제조하였고, 제조된 RFG 필름의 tensile strength(TS), water vapor permeability(WVP), water solubility(WS)는 각각 15.0 MPa, $2.70{\times}10^{-9}g\;m/m^2\;s\;Pa$, 53.8%였다. RFG에 nano-clay를 첨가한 복합필름은 TS가 증가하고 WVP와 WS는 감소하였다. XRD 분석과 SEM 측정 결과를 통하여 RFG/nano-clay 복합필름 내부에 박리형 구조를 형성함을 확인할 수 있었다. 결론적으로 본 연구 결과 RFG/nano-clay 복합필름은 생분해성 포장재로 적용될 수 있음을 시사한다.

• Fibers and Polymers
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• 제3권4호
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• pp.153-158
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• 2002

A series of waterborne polyurethanes (WBPU) were prepared from 4,4-dicyclohexylmethane diisocyanate ($H_{12}$MDI),2,2-bis(hydroxylmethyl) propionic acid (DMPA), othylenediarnine (EDA), triethylamine (TEA), and triblock glycol [TBG, ($\varepsilon$-caprolactone)$_{4.5}$-poly(tetramethylene ether) glycol (MW= 2000)-($\varepsilon$-caprolactone)$_{4.5}$: $(CL)_{4.5}$-PTMG-$(CL)_{4.5}$, MW=3000] as a soft segment. Two melting peaks of TBG at about 14$^{\circ}C$ and 38$^{\circ}C$ were observed indicating the presence of two different crystalline domains composed of CL and PTMG dominant component. The effect of soft segment content (60-75 wt%) on the colloidal properties of dispersion, and thermal and mechanical properties of WBPU films, the water vapor permeability (WVP) and water resistance (WR) of WBPU-coated Nylon fabrics, and the adhesive strength of WBPU- coated layer and Nylon fabrics was investigated. As soft segment contents increased, the water vapor permeability of WBPU- coated Nylon fabrics increased from 3615 to 4502 g/$m^2$day, however, the water resistances decreased from 1300 to 500 mm$H_2$O.O.

• 한국수산과학회지
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• 제32권5호
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• pp.582-586
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• 1999

생분해성으로서 가식성인 alginate 필름을 가공하기 위한 기초자료로써 $3\%$ $Na_2CO_3$ 추출시간 5시간으로 추출한 alginate로 만든 alginate 필름의 수증기 투과율과 장력성에 영향을 미치는 alginate농도와 가소제의 종류별 첨가량에 관한 조건을 측정한 결과는 다음과 같다. Alginate의 농도가 증가할수록 인장강도는 증가하였으나 수증기 투과율과 신장도는 감소하였다. 반면에 가소제의 첨가량이 증가할수록 수증기 투과율과 신장도는 증가하였으나 인장강도는 감소하였다. 가소제의 종류별에 따른 수증기 투과율은 glycerol, polyethylene glycol 및 sorbitol 첨가 필름 순으로 높게 나타났으며, 인장강도는 polyethylene glycol, sorbitol, glycerol 첨가 필름 순서이었으나 신장도는 그 반대되는 결과였다. 가소제의 종류와 필름의 색은 sorbitol 첨가 필름의 색이 가장 자았고, 황색도는 glycerol 첨가 필름이 가장 높았고, 적색도는 polyethylene glycol 첨가 필름이 가장 높았다. 그리고 전체적인 색의 차이에서는 polyethylene glycol 첨가 필름이 가장 높았다.

• 한국식품과학회지
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• 제29권2호
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• pp.255-260
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• 1997

이상의 결과에서 글루코만난 필름은 다른 천연 탄수화물고분자들의 필름들에 비해 비교적 우수한 인장 강도와 신장력을 가지며 높은 수분차단력을 보이나, 친수성 필름이 가지는 수분에 대한 민감성 때문에 수분을 직접 접촉할 때 높은 용해도를 보임을 알 수 있었다. 그리고 가소제의 함량의 증가에 따라 인장강도가 낮아지는 대신에 높은 신장력을 나타내었다. 글루코만난 필름은 적절한 여러 조건에 따라 넓은 범위의 물성변화를 가지는 친수성 필름으로서 식품포장산업에서의 다양한 이용가능성이 제시되었으며, 앞으로 적절한 가소제 및 첨가제의 이용, 수분에 대한 내성의 향상등의 연구가 더 필요하리라 사료된다.

• Food Science and Biotechnology
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• 제14권1호
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• pp.112-116
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• 2005

Composite films were prepared with soy protein isolate (SPI) and various clay minerals by casting from polymer and clay water suspension. Effects of clay minerals on film thickness, moisture content (MC), tensile strength (TS), elongation at break (E), water vapor permeability (WVP), and water solubility (WS) were tested. Properties including thickness, surface smoothness, and homogeneity of films prepared with organically modified montmorillonite (O-MMT), Wamok clay (W-clay), bentonite, talc powder, and zeolite were comparable to those of control SPI films. TS increased significantly (p<0.05) in films prepared with O-MMT and bentonite, while WVP decreased significantly (p<0.05) in bentonite-added films. WS of most nanocomposite films decreased significantly (p<0.05).