• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.857-862
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• 1989

Palm oil was crystallized and melted in the differential scanning calorimeter (DSC) in the presence and the absence of sucrose fatty acid ester (SE) at the different scanning rate. In the presence of SE, the crystallization temperature of palm oil was lowered, because SE inhibited the formation of mother crystal at the initial cooling stage The melting curves of SE added palm oil changed irregularly in the ${\alpha}-form$ transition and fusion entropy. It was that the presence of SE affected the molecular diffusion in palm oil.

• Journal of Adhesion and Interface
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• v.9 no.1
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• pp.16-21
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• 2008

Hybrid emulsions consisting of polyurethane and acrylic polymer were prepared by emulsion polymerization of acrylic monomers and polyurethane water dispersions (PUD) as an emulsifier. At first, cationic type of PUD was synthesized with IPDI, PTMG1000, MDEA, and acetic acid. Then, acrylic monomers, such as MMA and n-BA, were copolymerized with the PUD without adding further surfactant. The tensile properties and water resistance increased with increasing acrylic monomer ratio. The hybrid emulsions showed better properties than the emulsions simply blended with the PUD and the acrylic emulsions.

• Elastomers and Composites
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• v.54 no.4
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• pp.335-344
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• 2019

In this work, styrene butadiene rubber (SBR) and styrene butadiene styrene (SBS) were used to modify asphalt, resulting in SBR- and SBS-modified asphalt, respectively. The two modified asphalts were emulsified with a nonionic emulsifier (Span 60) and cationic emulsifiers (ID, DDA) and their phase stabilization was investigated via particle size, Zeta potential, and flow behavior analysis. With increasing amount of the mixed emulsifier, the particle size decreased, leading to an increase in viscosity. The shear thinning behaviors and Zeta potential values ranging from 35-65 mV were determined and remained considerably stable. In addition, the adhesion strength and compression strength of the SBR-and SBS-modified asphalt emulsion were evaluated via surface free energy examination. The remarkable adhesion and compression strengths were estimated when 5 phr ID and 6 phr DDA were added to the emulsified asphalt modified with SBR and SBS. Therefore ID and DDA, the two cationic surfactants, played significant roles in improving the dispersion and interfacial adhesion strength, resulting in the improved adhesion and compression strength of the emulsified asphalts modified with SBR and SBS.

• Journal of the Korean Applied Science and Technology
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• v.25 no.2
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• pp.115-122
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• 2008

The hydrosilylation is an addition reaction of Si-H bond to unsaturated double bonds, which provides a convenient mechanism to synthesize poly(dimethylsiloxane-co-methylsiloxane)copolymer having siloxy units in polymer backbone. In this study, Poly(dimethylsiloxane-co-methylsiloxane) copolymer was synthesized through the polymerization reaction of cyclopentasiloxane with poly(methyl-hydrogen) siloxane. Silicone-hydrogen functional group of the poly(dimethylsiloxane-co-methylsiloxane) copolymer was substituted to the alkyl groups by hydrosilylation. And their structure was analyzed with FT-IR, H-NMR and GPC instruments, respectively. Surface tension of the synthetic compounds is increased from 22dyne/cm to 25dyne/cm according to increase additional EO moles. The cmc which was evaluated by surface tension was ranged $10^{-5}$ to $10^{-4}mol/L$ and it was decreased according to increase of dimethyl siloxyl content. HLB number of these surfactants was evaluated 9.5 to 11.5 range. These silicone surfactants is applied to self-emulsifier defoamer and personal care products as surface tension depressant, emulsifier, foam control agent.

• Membrane Journal
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• v.29 no.4
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• pp.231-236
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• 2019

In this study, alginate-based hydrogel membranes composed of hydrogel beads and highly tough hydrogel matrix including moisturizing oil and natural emulsifier were prepared and their elution characteristics were evaluated. As a result, it was confirmed that the elution rate of the moisturizing oil component can be controlled within a desired range by controlling the composition of the hydrogel bead and the tough hydrogel matrix. In particular, it has been confirmed that by combining tough hydrogel having a structure of interpenetrating polymer network (IPN) and hydrogel beads, the physical stability of the membranes can be improved and the elution rate of the moisturizing oil can also be controlled more finely.

• Journal of Food Hygiene and Safety
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• v.24 no.3
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• pp.247-255
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• 2009

The purpose of this study was to investigate the storage stability of mayonnaise containing a different emulsifier and various levels of soybean paste powder. The mayonnaise with egg yolk as an emulsifier is E group according to the amount of soybean paste powder addition of 0%(E1), 3%(E2), 6%(E3) and mayonnaise with soy milk as an emulsifier is S group with soybean paste powder addition of 0%(S1), 3%(S2), 6%(S3). Storage stability of mayonnaise was determined during storage at $30{\pm}5^{\circ}C$ for 8 weeks. The peroxide value, TBA value, acid value of mayonnaise with addition of 6% soybean paste powder was significantly lower than that of 0% and 3% addition. The turbidity decreased according to storage period. The viscosity of mayonnaise was increased with increasing amount of soybean paste powder. Base on these results, addition of soybean paste powder in the mayonnaise improved oxidation stability during storage period.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1438-1443
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• 2009

The effects of adding additives such as gum, emulsifier, and enzyme both individually and as mixtures to frozen rice bread dough on baking quality were examined. Rice flours containing 17% vital gluten, and gum/emulsifier/enzyme blends were mixed and stored in a freezer at $-20^{\circ}C$ for 4 weeks. The rice doughs were removed from the freezer, thawed, and then followed the rice baking procedure. The dough freezing and frozen storage resulted in decreased volume of rice bread. The addition of guar gum/sodium stearoyl lactylate (SSL)/fungal $\alpha$-amylase blend improved volume of the rice bread obtained from rice dough during frozen storage. An increase in firmness of crumb was observed in rice breads during 3 days of storage at $25^{\circ}C$. Compared to the control dough without additives, addition of guar gum/ SSL blend or guar gum/ SSL/ fungal $\alpha$-amylase blend into frozen dough significantly reduced the crumb firmness of rice bread, indicating a significant antistaling effect.

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.767-772
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• 2006

In this study, we sought to produce a double layer microcapsule containing Lactobacillus sp. as the core material. The conditions for this microencapsulation process were optimized for the formation of a microcapsule with high storage stability. The effects of the ratio of[core material] to [wall material], the type and concentration of emulsifier used, the stirring rate(dispersibility) and the temperature of the dispersion fluid on the microencapsulation yield were studied. The optimal concentration and type of emulsifier required in order to allow for the stable formation of a W/O type emulsion (a primary process in double layer microencapsulation) were 1.00% (w/w) and polyglycerol polyricinileate (PGPR, HLB 0.6). However, the optimal concentration and type of emulsifier required to construct a W/O/W type emulsion (a secondary process in double layer microencapsulation), were 0.65% (w/w) and polyoxyethylene sorbitan monolaurate (PSML, HLB 16.7). Finally, we obtained a maximum yield of microencapsulation with a dispersion fluid stirring rate of 270rpm and a dispersion fluid temperature of 10$^{\circ}C$ after spraying a W/O/W type emulsion into the dispersion fluid.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.670-678
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• 2017

Self-emulsifiable polyethylene (PE) wax was prepared using acrylic acid grafted PE wax with potassium hydroxide and various emulsifiers for the economic production of PE wax emulsion. Modification reaction completion was confirmed that the peak from carbonyl group of acrylic acid disappeared and the new peak from carboxylic acid salts appeared in the FT-IR (Fourier transform infrared) spectrum data. Self-emulsifiable properties of the modified PE wax were investigated by the emulsion size and the stability of wax emulsion without any additional emulsifiers. According to self-emulsifiable properties, the emulsion size and stability were varied on the concentration and structure of the emulsifier. The greater emulsion concentration and hydrophilic poly(ethylene oxide) (PEO) characteristics of the emulsifier resulted in the smaller emulsion size and better emulsion stability. In addition, the use of emulsifiers mixture was more effective to obtain smaller size and uniform distribution of emulsion than that of single emulsifier in PE wax modification reaction. Especially, modified PE wax with OAE-5 and LAE-15 emulsifiers mixture shows excellent performance in terms of the smallest emulsion size ($4.34{\mu}m$) and emulsion stability.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.423-428
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• 2003

Stabilities of W/O emulsions containing eugenolchitosan (EuCs) prepared from chitosan and eugenol were compared to determine the optimal conditions for the ratio of water (core phase) to corn oil (continuous phase), the concentration of EuCs, storage temperature, and the extent of homo-mixing. The optimal ratio of water to corn oil was 2:3 (w/w). The effects of EuC concentrations, and singular vs. binary system of emulsifiers on the storage stability of the emulsion were investigated with EuCs and polyoxyethylene sorbitan monolaurate. The emulsion was stable, showing more than 95% emulsion stability index (ESI) value, when the concentration of EuCs was more than 0.18% (w/v). ESI value of binary emulsifier system was almost equal to that of singular emulsifier system at the concentration of 0.18% (w/v). At this singular emulsifier system, the W/O emulsion formed by EuCs had ESI value of 100%. The optimal concentration of EuCs was determined as 0.18% (w/v). The highest stability of the emulsion was obtained from the homo-mixing at 11,000 rpm for 10 sec and the storage temperature ranging $25{\sim}65^{\circ}C$. EuCs produced from this study was mutagenecity-negative on Ames test and contained no heavy metal ions.