• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1997.11a
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• pp.47-52
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• 1997

This study was carried out to investigate effects of fabric properties and the changes of microclimates on comfort sensations and to identify effective varuables on clothing wear comfort sensations. A wied range of nontreated and functionally treated woven fabrics, knits, and nonwoven fabrics and test garments made of them were used as specimens. Linear structural equation was used to analyze causal relation among the variables on a path diagram. The results were as follows: 1. Almost of causal relations among variables were significant excdpt the effects of fabric properties including air permeability and water-vapor permebility on the changes of microclimate temperature. 2. Fabric properties were most effective variables on clothing wear comfort sensations including thermal sensation, subjeceive wettedness, and overall comfort and therefore comfort sensations and fabric properties were identified for improving clothing comfort.

• Food Science and Biotechnology
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• v.14 no.1
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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.

• Food Science and Biotechnology
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• v.14 no.1
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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).

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.38-41
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• 2003

Recently, Waterhorne polyurethane(WBPU) have been used for a wide range of commercial applications due to the increasing environmental regulation to reduce low-volatile organic compounds in coating and adhesives materials [1-8]. The WBPU was used in coating industry on fiber at first, and its market is increasing these days. Especially, the Waterborne polyurethane film even is widely used in the field of breathable coating fiber or medical science [9-10]. Water vapor permeability(WVP) is the key property for application to breathable coating fiber. (omitted)

• Archives of Pharmacal Research
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• v.28 no.3
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• pp.364-369
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• 2005

HPMC (Hydroxypropyl methylcellulose) was chemically modified, using maleic anhydrides, to obtain pH-sensitive HPMCAM (Hydroxypropyl methylcellulose acetate maleate) polymers for use as novel duodenum-specific coating agents. The pharmaceutical properties of HPMCAM, such as film forming, acid values, pH-sensitive values, water vapor permeability, tensile strength and Tg, were investigated, and found to show good film forming properties. The pH­sensitive values were 3.0 to 3.7. In vitro results demonstrate that HPMCAM could completely suppress drug release within 2h in a simulated gastric fluid (pH 1.2) and rapidly release the drug in a simulated pathological duodenal fluid (pH 3.4). These results indicate that HPMCAM might be a useful material for a duodenum-specific drug delivery system.

• 한국포장학회:학술대회논문집
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• 2006.11a
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• pp.54-73
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• 2006

Four different types of chitosan-based nanocomposite films were prepared using a solvent casting method by incorporating with four types of nanoparticles, i.e., an unmodified montmorillonite (Na-MMT), an organically modified montmorillonite (Cloisite 30B), a Nano-silver, and a Ag-zeolite (Ag-Ion). X-ray diffraction patterns of the nanocomposite films indicated that a certain degree of intercalation was formed in the nanocomposite films, with the highest intercalation in the Na-MMT-incorporated films followed by films with Cloisite 30B and Ag-Ion. SEM micrographs showed that in all the nanocomposite films, except the Nanosilver-incorporated one, nanoparticles were dispersed homogeneously throughout the chitosan polymer matrix. Consequently, mechanical and barrier properties of chitosan films were affected through intercalation of nanoparticles, i.e., tensile strength (TS) increased by 7-16%, while water vapor permeability (WVP) decreased by 25-30% depending on the nanoparticle material tested. In addition, chitosan-based nanocomposite films, especially silver-containing ones, showed a promising range of antimicrobial activity.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.133-137
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• 2006

Wheat gluten-chitosan composite film (WGCCF) can prevent moisture migration and enhance the antimicrobial properties of gluten in intermediate-moisture foods like sandwiches. To mimic the structure of actual sandwich-type products we developed multi-layer food models, where moisture content and water activity differ. Water activity gradients direct moisture migration and therefore determine product characteristics and product stability. A 10% wheat gluten film-forming solution was mixed with chitosan film-forming solution (0-3%, w/w) and evaporated to generate WGCCF. Addition of 3% chitosan enhanced the mechanical properties of the film composite, lowered its water vapor permeability, and improved its ability to protect against both, Streptococcus faecalis and Escherichia coli, in a 24 hr sandwich test (reduction of 1.3 and 2.7 log cycles, respectively, compared to controls). Best barrier and antimicrobial performance was found for 3% chitosan WGCCF at pH 5.1. Film of this type may find application as barrier film for intermediate-moisture foods.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.2 s.25
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• pp.127-135
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• 2006

Experimental studies of the cylindrical sintered-copper wick heat pipes were carried out to investigate the capillary heat transfer characteristics. Six models of the sintered-copper wick heat pipes were manufactured and tested to evaluate the heat transport limitations and the thermal characteristics. Also the performance of the heat pipes was analyzed theoretically and compared with the test results. The heat pipe models are divided into two sintered-wick groups and the nominal particle sizes are $180{\mu}m$(wick #1) and $200{\mu}m$(wick #2) respectively The experimental results showed that, the porosity of wick #1 was higher than that of wick #2, and also the wick #1 was generally superior than the wick #2 for the heat transport capability. The maximum heat transport rates were increased as the wick thicknesses and the vapor temperatures were increased.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1203-1206
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• 2008

Silk fibroin (SF) film containing catechin was prepared and the antimicrobial activity as well as physical property of the film was examined. Tensile strength of the SF film decreased with increasing concentration of catechin, and water vapor permeability of the film decreased. The film's antimicrobial activity against Escherichia coli O157:H7 increased with increasing catechin concentration. Sausage samples were inoculated with E. coli 0157:H7 and Listeria monocytogenes, and the sausage packaged with the SF film containing catechin had a decrease in the populations of E. coli O157:H7 and L. monocytogenes by 0.83 and 0.85 log CFU/g after 12 days of storage, respectively, compared to the control. In addition, the sausage had a better quality than the control regarding lipid oxidation. Our results indicate that sausages can be packed with the SF film containing catechin to extend shelf life.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.631-634
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• 2006

Soy protein isolate (SPI) films were supplemented with cinnamaldehyde (CA) at concentrations of 0.1-0.5 mL/5 g SPI. The effects of CA on film color, tensile strength (TS), percent elongation at break (E, %) and water vapor permeability (WVP) of SPI films were investigated. Generally, total color difference (${\Delta}E$), WVP, and TS of SPI films increased gradually, while E and TSM decreased significantly (p<0.05) as the amount of cinnamaldehyde in the SPI films increased. Cinnamaldehyde can be used as a potential cross-linking agent for preparing SPI films by improving mechanical strength and water resistant properties.