AK ChemTech Central Research Laboratory

Daejeon, South Korea

AK ChemTech Central Research Laboratory

Daejeon, South Korea

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Lim J.,Dongguk University | Lee S.,Dongguk University | Kim B.,AK ChemTech Central Research Laboratory | Lee J.,AK ChemTech Central Research Laboratory | Choi K.,AK ChemTech Central Research Laboratory
Applied Chemistry for Engineering | Year: 2011

The CMCs of LA and LA3 nonionic surfactants obtained from the reaction between glycidol and lauryl alcohol were found to be 0.97 × 10 -3 mol/L and 1.02 × 10 -3 mol/L respectively and the surface tensions for 1 wt% surfactant were 26.99 and 27.48 mN/m respectively. Dynamic surface tension measurements using a maximum bubble pressure tensiometer showed that the adsorption rate of surfactant molecules at the interface between the air and the surfactant solution was found to be relatively fast in both surfactant systems, presumably due to the high mobility of surfactant molecules. The contact angles of LA and LA3 nonionic surfactants were 27.8 and 20.9° respectively and the dynamic interfacial tension measurement by a spinning drop tensiometer showed that interfacial tensions at equilibrium condition in both systems were almost the same. Also both surfactant systems reached equilibrium in 2~3 min. Both surfactant solutions showed high stability when evaluated by conductometric method and the LA nonionic surfactant system provided the higher foam stability than the LA3 nonionic surfactant system. The phase behavior experiments showed a lower phase or oil in water (O/W) microemulsion in equilibrium with an excess oil phase at all temperatures studied. No three-phase region was observed including a middle-phase microemulsion or a lamellar liquid crystalline phase.


Lee S.,Dongguk University | Kim B.,AK ChemTech Central Research Laboratory | Lee J.,AK ChemTech Central Research Laboratory | Lim J.,Dongguk University
Applied Chemistry for Engineering | Year: 2011

The critical micelle concentration (CMC) of sorbitan laurate SP 20 surfactant in this paper was near 7.216 × 10 -4 mol/L and the surface tension at CMC was about 26.0 mN/m, which showed higher CMC and lower surface tension than those of octylphenol ethoxylate octylphenol ethoxylate (OPE) 10 surfactant. Dynamic surface tension measurement using a maximum bubble pressure tensiometer showed that the adsorption rate at the interface between air and surfactant solution was found to be slower with SP 20 surfactant, presumably due to a low mobility of SP 20 surfactant monomer. The contact angle of SP 20 surfactant solution was observed to decrease with an increase in surfactant concentration and showed a larger value than that of OPE 10 surfactant solution. Half-life time for foams generated with 1 wt% surfactant solution was also larger with SP 20 surfactant, which indicated higher foam stability with SP 20 surfactant. Dynamic behavior study reveals that the solubilization of n-decane oil was much lower with SP 20, which is in good agreement with experimental results of foam stability, contact angle and CMC. Dynamic interfacial tension measurement by a spinning drop tensiometer shows that interfacial tensions at equilibrium condition in both systems were almost the same but the time required to reach equilibrium was longer with SP 20.


Lee S.M.,Dongguk University | Lee J.Y.,Dongguk University | Yu H.P.,AK ChemTech Central Research Laboratory | Lim J.C.,Dongguk University
Journal of Industrial and Engineering Chemistry | Year: 2016

In this study, environment friendly nonionic surfactants were synthesized from sugar base and their structure was characterized by 1H-NMR, 13C-NMR and FT-IR. The newly synthesized SA08 series surfactants showed excellent interfacial properties such as low CMC, surface tension and interfacial tension, and superior foam stability. Detergency tests using three different types of artificial soils have revealed that the synthesized surfactants showed moderately good detergency presumably due to excellent interfacial properties and stereoscopic molecular structure of SA08 series surfactants. Environmental compatibility test showed that SA08-07 surfactant exhibited low toxicity compared with conventional nonionic and anionic surfactants and excellent biodegradability. © 2016 The Korean Society of Industrial and Engineering Chemistry.


Song E.,Dongguk University | Kim D.,Dongguk University | Kim B.J.,AK ChemTech Central Research Laboratory | Lim J.,Dongguk University
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2014

Surface modification of CaCO3 nanoparticles by two kinds of anionic surfactants, such as linear alkylbenzene sulfonic acid (LABSA) and branched alkylbenzene sulfonic acid (BABSA), was investigated by a quartz crystal microbalance with dissipation monitoring (QCM-D) measurement and contact angle analysis. Basically, both surfactant systems showed the same trend in the measurements of QCM-D and contact angle. Contact angle measurement has shown that CaCO3 surface becomes more hydrophobic as surfactant concentration increases. However, the use of excess surfactant has led to the reverse change in surface property of CaCO3 particles from hydrophobic to hydrophilic. QCM-D measurement using a quartz crystal coated with CaCO3 revealed that monolayer adsorption of surfactant molecules at the particle-water interface occurs in a low surfactant concentration region and the thickness of forming molecular layers was found to be in the order of the length of a single surfactant molecule. On the other hand, both mass of adsorbed surfactant molecules and the thickness of molecular layers indicated bilayer adsorption of surfactant molecules in a high surfactant concentration region, which evidently resulted in an increase in hydrophilicity of CaCO3 surface. Visual floating test has shown a good agreement with measurements of contact angle and QCM-D. © 2014 Elsevier B.V.


Lim J.C.,Dongguk University | Lee M.C.,Dongguk University | Lim T.-K.,Dongguk University | Kim B.J.,AK ChemTech Central Research Laboratory
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2014

In this study, environmentally friendly nonionic surfactants were synthesized by the reaction of sorbitol and decanoic acid followed by addition of ethylene oxide. The structure of the product was elucidated by 1H NMR, 13C NMR and FT-IR and the interfacial properties such as critical micelle concentration (CMC), surface tension, interfacial tension, contact angle and foam stability were measured. These newly synthesized surfactants were used to prepare emulsion-type pressure sensitive adhesive (PSA) by emulsion polymerization and adhesive properties were measured in order to investigate the possibility of substituting a traditional nonylphenol ethoxylate surfactant NPE40. The PSA prepared by a newly synthesized surfactant SA10-40 showed better adhesive properties in peel strength and holding power than those of NPE40 and Tween40. © 2014 Elsevier B.V.

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