• Journal of the Society of Cosmetic Scientists of Korea
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• v.22 no.2
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• pp.167-173
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• 1996

The stability of gel structured emulsion and the effect of polyols on it have been studied by rheological property and interfacial tension. In this paper, three types of gel structured emulsions were prepared by using three polyols respectively(glycerine for sample 1, 1.3 BG for sample 2, PG for sample 3). And both complex modulus($G^*$) and loss angle[$\delta$ = tan-1(G"/G')] of samples were investigated against oscillating shear stress and frequency($\omega$). The results show sample 1 is most highly consistent with oscillating shear stress. And the results were compared with those of accelerated tests concerning storage stability of gel structured emulsion. To correlate consistency of rheological property with storage stability, interfacial tension from which adsorption efficiency of surfactant(Octyldodecyl Ether) could be known was measured. Sample 1 showed the largest value of [$d{\gamma}/dIn_{Cconc. of surfactant}$] in Gibbs equation. In summary, the prediction of stability could be correctly made by the consistency of rheological property(G*,$\gamma$) of gel structured emulsion against oscillating shear stress and it could be supported by measuring interfacial tension. And polyol affected the value of [$d{\gamma}/dIn_{Cconc. of surfactant}$], consequently affected the stability.lity.

• Food Engineering Progress
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• v.15 no.2
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• pp.175-181
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• 2011

By using supercritical carbon dioxide fluid, an attempt was made to extract surface-active substances from defatted rice bran. Extraction was carried out according to D-optimal design and results were analyzed by response surface methodology to establish optimum condition. It was found that pressure, temperature and co-solvent (ethanol) influenced in a different extent on the extraction efficiency (i.e., yield and interfacial tension) of surface-active substances. Among them, co-solvent was found to be a major influencing factor, where maximum yield (2.62%) was observed at the highest content (250 g). In addition, it also affected most on the interfacial tension at the oil-water interface but in this case the lowest interfacial tension value (9.51 mN/m) was found when added lowest (50 g). In conclusion, it was estimated that the optimum extraction condition was to be pressure 350bar, temperature $62^{\circ}C$ and co-solvent content 50 g in this study, where extraction yield was 0.69% and interfacial tension to be 10.1 mN/m.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.451-456
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• 1994

Alkyl polyglucosides (APG), so called natural nonionic surfactants, are prepared with glucose from corn starch and fatty alcohol from palm and/or coconut oil. When we studied on interfacial properties of APG, surface and interfacial tension, cmc, foaming and effectiveness, according to degree of polymerization of glucose unit (D.P.=1.2~1.8) and alkyl chain length, the former hardly affects but the latter greatly affects on them. The order of detergency for fatty acid soils decreased as followings ; APG 0814> APG 1214> APG 10> APG 0810> APG 08, and the samples with lowest interfacial tension and maximum adsorption had a better detergency.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.227-232
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• 2008

In this research, organic extracts from roots of platycodon grandiflorum was tested to see the possibility for cosmetic natural surfactant. Interfacial properties of extracts of Platycodon grandiflorum was checked for interfacial tension, forming force, dispersion force, emulsion force, emulsion activity, and emulsion stability. At 0.005 wt% concentration, the interfacial tension against the caster oil was 11.5 dyn/cm which was lower than that of Tween 40 and quillaja bark. Extracts of Platycodon grandiflorum showed excellent emulsification activity and stability for cosmetic oils such as olive oil, soybean oil, and canola oil. In patch test using 2-5% of the extract and glycerin, the extract showed mild skin irritation. From the experiment, the extracts of platycodon grandiflorum root showed good interfacial properties as a cosmetic agent with minor skin irritation.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.193-199
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• 2020

The effects of the composition of the dishwashing detergent on interfaces of the oil (O) and the aqueous (W) solution in addition to the cleaning effects of interfacial properties were investigated. Also, the cleaning power of the oil contaminated on the surface of the dish according to each composition and the residuals of the contaminants and the cleaning agent after the washing rinses were evaluated. The removal of contaminated oil on the solid (S) surface in the composition of the cleaning agents used in this study was strongly related to the interfacial properties between the W/O/S, and was particularly dependent on the forward and backward dynamic contact angles. When both contact angles were low at the same time, the permeability of the cleaning solution was so high that the contaminated oil showed a high removal effect. The smaller the interfacial tension of O/W was, the better emulsification of the contaminated oil, the higher the interfacial tension, and the poorer emulsification were achieved. However, the emulsification effect did not significantly affect the cleaning power. In particular, in the case of the cleaner having low interfacial tension, the cleaning material remained on the surface of the solid after washing.

• 한국전산유체공학회:학술대회논문집
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• 2006.10a
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• pp.9-10
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• 2006

A numerical method for simulating tree surface flows including the surface tension is presented. Numerical scheme is based an a fractional-step method with a finite volume formulation and the interface between liquid and gas is tracked by Volume of Fluid (VOF) method. Piecewise Linear Interface Calculation (PLIC) method is used to reconstruct the interface and the surface tension is considered using a Continuum Surface Force (CSF) model. Several free surface flow phenomena were simulated to show its effectiveness to find such phenomena.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.3
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• pp.348-354
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• 1994

The changes of surface activities in the aquaous solutions of mixed surfactants composed of linear sodium dodecylbenznesulfoate (LAS), polyoxyethylene nonyl phenylether (PE, EO=10) and polyethylene glycol monolauryl ether (LE, EO=25) have been studied. Addition of nonionic surfactants to LAS reduces the surface tension, especially at the lower concentration than cmc. The interfacial tension of olive oil/LAS was lower than the other surfactant solutions. The removal of triolein from cotton fabrics by nonionic surfactants and mixtures is higher than by LAS. The addition of NaCI to surfactant solutions even though reduces surface tension smaller but enthances oil removal more than that of $CaCl_2$.

• Transactions of Materials Processing
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• v.21 no.5
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• pp.291-297
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• 2012

In this paper, the effect of back tension in multi-pass drawing or wiredrawing on the central bursting defect is investigated using finite element predictions. A rigid-plastic finite element method was used together with the McClintock damage model. Central bursting defects under different back tension stress values ranging from 0% to 20% of the yield strength of the material were predicted and they were compared to understand the effect of the back tension stress values on the central bursting defect. It is found that the level of back tension has a strong influence on the cumulative damage. Thus, higher back tension raises the possibility of the central bursting defect occurring, even though it decreases the interfacial pressure between the die and the work piece.

• Composites Research
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• v.26 no.5
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• pp.303-308
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• 2013

Carbon fiber (CF) reinforced polypropylene (PP) compositeis was increased to amount consumed. In this study, recycle of composites by recycle times. CF was containing 20%. Mechanical and interfacial propertis of CF/PP was evaluation for number of recycle time. Mechanical assessment of CF/PP was tension, bending, fatigue tension test and izod test method. Interfacial assessment of CF/PP was wettability test and FE-SEM of fracture surface method. Fiber and matrix was changed to recycle time. The more recycle of CF/PP, the more interfacial bonding was decreased. Because fiber and matrix was damaged to thermal damage. And then reinforced CF was shorter than original shape.

• Journal of the Korean Chemical Society
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• v.23 no.4
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• pp.210-216
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• 1979

A simple method to calculate the interfacial tension between two immiscible molten polymers has been developed. The theory is based on the significant structure theory of liquids. The energy of adhesion is expressed as a geometric mean of the cohesion energies multiplied by correction factor $({\Phi}12)$, ${\Delta}E_{12}={\Phi}_{12}\sqrt{{\Delta}E_{11}{\Delta}E_{22^{\circ}}$. In the calculation of ${\Delta}E_{11}\;and\;{\Delta}E_{22}$, a quasilattice of polymer chains has been assumed. It is assured that, besides the dispersion force, the polar force interactions between polymer constituent groups should be considered in the calculation of the interfacial tensions.