• Elastomers and Composites
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• v.43 no.4
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• pp.221-229
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• 2008

Starch as matrix polymer was used to do graft copolymerization with 2-ethylhexylacrylate, methyl methacrylate and acrylic acid. The polymerization was carried out by radical emulsion polymerization with increasing contents of starch. When 0.174% of $\alpha$-amylase as enzyme for starch was added, it was found that it made the best stable emulsion. The glass transion temperature of the polymerized material was increased with starch contents. The particle size and viscosity of the emulsion increased with starch contents due to the increased hydroxy group. Peel strength also increased with contents of starch because the enhanced hydroxy group caused to increase affinity between substrate surface and polymer materials. However, the initial tackiness decreased with starch contents owing to film hardness by higher glass transion temperature.

• Korea-Australia Rheology Journal
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• v.15 no.3
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• pp.125-130
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• 2003

The emulsion stability of cosmetic creams based on the water-in-oil (W/O) high internal phase emulsions (HIPEs) containing water, squalane oil and cetyl dimethicone copolyol was investigated with various compositional changes, such as electrolyte concentration, oil polarity and water phase volume fraction. The rheological consistency was mainly destroyed by the coalescence of the deformed water droplets. The slope change of complex modulus versus water phase volume fraction monitored in the linear viscoelastic region could be explained with the resistance to coalescence of the deformed interfacial film of water droplets in concentrated W/O emulsions: the greater the increase of complex modulus was, the more the coalescence occurred and the less consistent the emulsions were. Emulsion stability was dependent on the addition of electrolyte to the water phase. Increasing the electrolyte concentration increased the refractive index of the water phase, and thus decreased the refractive index difference between oil and water phases. This decreased the attractive force between water droplets, which resulted in reducing the coalescence of droplets and increasing the stability of emulsions. Increasing the oil polarity tended to increase emulsion consistency, but did not show clear difference in cream hardness among the emulsions.

• Journal of the Korean Applied Science and Technology
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• v.23 no.1
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• pp.1-11
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• 2006

The W/O emulsion was formed by mixing hydrophobic nonion surfactants of span 80 and tween 60 with kerosine, and by adding sodium silicate aqueous solution. Precipitating the W/O emulsion by sodium bicarbonate resulted in spherical silica particles. Shape and size distribution of silica particles were observed. The particles were spherical and they have narrow size distribution. Particle sizes were 9.29, 7.39 and $5.73\;{\mu}m$ at homogenizer speed of 2500, 3000, and 3500 rpm, respectively. The particle size was decreased by increasing agitation speed due to the formation of emulsion droplet. At fixed agitation speed, absorbed paraffin oil weight were measured and the $SiO_2/Na_2O$ mole ratio effects on particle size were investigated. Particle size was decreased by increasing the mole ratio of $SiO_2/Na_2O$.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.262-262
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• 2006

Biodegradable and amphiphilic di-block and tri-block copolymers, prepared with monomethoxy poly ethylene glycol (MPEG) and ${\varepsilon}-caprolactone\;({\varepsilon}-CL)$, were used for the application of W1/O/W2 multi- emulsion capsules. The effects of topology and the ratio of hydrophilic moiety of PCL-based polymers on the encapsulation efficiency of the $W_{1}/O/W_{2}$ multi-emulsion capsules containing Ascorbic Acid-2-Glucoside (AA-2-G) were investigated. The ratio of PEG and PCL was 1:0.5, 1:0.75, 1:1, and 1:1.25. PEG-PCL block copolymers were added to the first step of the preparation of $W_{1}/O$ emulsions. The dispersion stability, the particle size, the morphology of the $W_{1}/O/W_{2}$ multi-emulsion capsules were observed using an on-line turbidity meter, dynamic light scattering (DLS), a confocal microscopy (with FITC) and an optical microscopy. Biodegradable behavior of the PEG-PCL block copolymers and release behavior of AA-2-G were also observed by Gel Permeation Chromatography (GPC) and High Performance Liquid Chromatography (HPLC).

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.5
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• pp.424-431
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• 2009

Treatment for water repellency on the carbon supports of GDL which composed a part of MEA has been suggested as a solution to prevent flooding. PTFE is a fluoropolymer that has hydrophobic property and a PTFE emulsion was selected as waterproof agent in this investigation. Carbon paper was coated by PTFE emulsion with different particle size of 5~500 nm and 3~$5\;{\mu}m$ as various concentration. PTFE coated carbon paper has difference in weight variation changed proportionally at PTFE concentration and coating times. Then gas permeability of the coated carbon paper with emulsion of 3~$5\;{\mu}m$ PTFE was changed vastly. Characteristics of carbon paper coated with different PTFE emulsion were analyzed by FE-SEM, FT-IR spcetroscopy and were evaluated by weight variations, gas permeability and water contact angle.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.67-70
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• 2010

This study investigates the physical properties of the acrylic emulsion mortar according to variable composition set of redispersible emulsion powders. This materials have to be composed of many types of binders and chemical additives. So it is difficult to decide suitable mixing proportion of composition materials. The redispersible emulsion powders using "2, 4, 6, 8kg" of EVA polymers dispersion ranges are prepared with acrylic emulsion mortars and were tested for basic characteristics such as flexural, and compressive strength, wheel load. Through experiments we found that the improved formula to satisfy the standard of wheel load by EVA polymers, and the masration rangs between about 2.0% to 2.6% which the white portland cenmet and EVA polymers is good for resistauce wheel load.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.984-989
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• 1999

This study was carried out to investigate the effects of ethanol extracts on lipid oxidation of oil emulsion. The results are as follows; The scavenging ability of plant extracts for hydroxyl radical was found, and plant extracts played an important role as a strong chelating agents to bind iron if Fe2+ ion exists in oil emulsion. Pinus densiflora(PD), Lithospermum erythrorhizon(LE) and PD＋LE acted as strong chelating agents to bind iron to reduce lipid oxidation in oil emulsion. The content of Fe2+ ion in ethanol extracts from LE and PD＋LE were significantly higher(p<0.05) than that of ethanol extracts from PD. The content of total iron has same tendency. The ascorbic acid content of PD(16.36ppm) was slightly higher than those of LE(13.08ppm). Electron donating ability of PD was significantly higher(p<0.05) than those of LE. However, the superoxide(SOD) like ability of LE showed a little higher than those of LE and PD＋LE, which means the strong antioxidant activity of LE. The nitrite scavenging effects were dependent on pH value, however, they decreased as pH value increased. Especially, they almost didn't show the nitrite scavenging effect in pH 6.0. In conclusion, the PD and LE extracts may be used as natural antioxidant sources to reduce lipid oxidation in oil emulsion.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.467-472
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• 2005

Asphalt emulsion is manufactured by the emulsification of asphalt, and is considered as an energy-saving, ecologically safe material because it does not need any heating processes with gas emission and fire hazard in its use. This study is concerned with evaluating the feasibility of the use of an asphalt emulsion as a poly-meric admixture. Asphalt-modified mortars using an experimentally manufactured asphalt emulsion were prepared with various polymer-cement ratios, and tested far the mechanical properties such as strengths and adhesion and the properties related to durability such as water absorption, permeation, carbonation and chloride ion penetration. As a result, the waterproofness, carbonation resistance and chloride ion penetration resistance of the asphalt-modified mortars were markedly improved with an increase in the polymer-cement ratio, but their compressive strength and adhesion to mortar substrates were reduced with increasing polymer-cement ratio. Therefore, it is recommended to control their polymer-cement ratio to be $10\%$ or lower in their practical applications. Further study to improve their compressive strength and adhesion is needed.

• Biomedical Science Letters
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• v.11 no.2
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• pp.221-225
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• 2005

To investigate the spectroscopic findings of embolized lesions induced with a fat-emulsion technique with magnetic resonance images (MRI). A fat emulsion was made with 0.1 ml of triolein and 20 ml of normal saline. In 12 cats, the internal carotid artery was infused with the fat emulsion. Contrast-enhanced T1-weighted MRI and multivoxel spectroscopy were obtained at 1 hour, 1 and 4 days, and 1 week after embolization. NAA (N-acetylaspartate), Cr (creatine) and Cho (choline) were evaluated on the spectroscopy. Statitistical analysis wsperformed at the embolized and contralateral normal hemisphere in the integral and amplitude of NAA, Cr and Nho in time course. Also NAA/Cr and Cho/Cr were compared in both hemisphere and in time course. The emboli zed lesions showed contrast enhance ments on Gd-enhanced Tl-weighted i~ages at 1 hour. This contrast enhancement was decreased at day 1, and id not appear agter day 4. In spectroscopy, the embolized hemisphere showed no statistical difference to the normal contralateral side at 1 hour and in time course. NAA/Cr and Cho/Cr were not significantly different in both hemispheres at 1 hour and in time course. Cerebral-fat embolism induced by a triolein emulsion in cats revealed no statistical difference on MR spectroscopy. Triolein-emulsion can be used in the study of blood-brain barrier.

• Textile Coloration and Finishing
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• v.22 no.3
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• pp.229-238
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• 2010

Poly($\varepsilon$-caprolactone) nano/microcapsules(nmcPCL) containing phytoncide oil were synthesized by emulsion diffusion method using ethyl acetate and poly(vinyl alcohol) (PVA) as an organic solvent and an emulsion stabilizer respectively. The influence of the degree of saponofication of the PVA and the weight ratio of core to wall materials was investigated to design nanocapsules in terms of particle size, morphology, and emulsion stability. The encapsulated nmcPCL were characterized by FT-IR spectrometry, particle size analyzer and scanning electron microscope. Mean size of nanocapsules prepared with PVA with a degree of saponofication of 87% was smaller than those of PVA with a degree of saponofication of 98.5% and the mean particle size of the capsules decreased with increasing core/shell ratio.