• 대한화학회지
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• 제16권4호
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• pp.205-207
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• 1972

새로히 합성한 dodecylquinolinium bromide의 수용액에서 표면장력과 전기전도도 측정치로 부터 critical micelle concentration을 결정하였다. 표면장력법으로 결정한 c.m.c.의 값은 $3.34 {\times} 10^{-3}mole/l$이고 전기전도도법으로 결정한 값은 3.41 {\times} $10^{-3}$mole/l이었다. 이값들은 dodecylpyridinium bromide의 그것보다 작은데 이는 dodecylquinolinium bromide의 소수성 group이 큰데서 오는 것으로 생각된다.

• 대한화학회지
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• 제10권2호
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• pp.103-108
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• 1966

The effect of temperature on the critical micelle concentration of dodecylpyridinium chloride has been determined by electrical conductance method over the range from $5^{\circ}C\;to\;50^{\circ}C$. The values of the change in heat content, ${\Delta}H_m$, and the other thermodynamic parameters have been estimated using the equation of temperature dependence on the critical micelle concentration for the same temperature range. The significance of these thermodynamic quantities and their relations to the various current theories of micelle forming processes were discussed.

• 대한화학회지
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• 제10권4호
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• pp.161-165
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• 1966

The critical concentrations of ${\alpha}$-amino capric acid for micelle formation have been determined by the surface tension measurements in both acidic and alkaline solutions, and also by the dye titration using Rhodamine B in alkaline solutions. The critical micelle concentrations obtained by the two methods show the good agreements within experimental errors. Since ${\alpha}$-amino acid is an ampholyte, it may aggregate to form the micelles in both more acidic and basic media than its isoelectric point. It is found that the basic media are rather preferable for the micelle formation than the acidic media. The effect of gegen ions upon the critical concentration for micelle formation in alkaline media is similar to that expected from the salt effect on the CMC (Critical Micelle Concentration).

• Bulletin of the Korean Chemical Society
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• 제28권10호
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• pp.1857-1859
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• 2007

• Archives of Pharmacal Research
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• 제15권2호
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• pp.126-129
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• 1992

The critical micelle concentrations (CMCs) of aqueous solutions of a nonionic surfactant, polyoxyl 23 lauryl ether in the presence of various concentration of urea and its derivatives were measured. The CMC of the surfactant increase in proportion to the concentration of the additives, and the CMC-raising activities increased with more and longer alkyl grups substituted in urea. The CMC shift values were successfully correlated with the cloud point shift values and the protein-denaturing activities of the additives, respectively. These results suggest that the micelle formation, clouding of the surfactant and the protein denaturation are a closely related phenomenon, and a common mechanism is operating which might be the hydrophobic interaction.

• 대한화학회지
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• 제18권5호
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• pp.354-357
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• 1974

모노스테아르산설탕의 critical micelle concentration(CMC)를 $20^{\circ}C$와 $40^{\circ}C$사이의 여러 온도에서 측정하였고 이어서 디에스테르가 첨가 되었을 때의 CMC를 측정하였다. 디에스테르가 포함된 모노에스테르의 용액에서는 용액의 표면장력이 약 40dyne $cm^{-1}$가 될 때 표면장력 대 농도 곡선이 불연속을 나타내는데 이것은 모노에스테르와 디에스테르와의 회합체가 이 영역에서 표면배열을 갑자기 바꾸기 때문이라고 생각된다.

• 한국응용과학기술학회지
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• 제27권4호
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• pp.545-551
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• 2010

Hydrophobically monoendcapped poly(sodium acrylate)s formed hydrophobic microdomains in water. This was concluded on poly(sodium acrylate)s with a linear $C_{12}$-alkyl chain attached specifically at the end of the polymer. There was no well defined CMC (critical micelle concentration), but rather a gradual transition from a micelle free solution to a micelle solution. Steady state fluorescence spectroscopy indicates that the micro domains are rather hydrophobic. At pH 5 in the abscence of salt and at pH 9 in the prescence of 1 M sodium citrate the CAC (critical aggregation concentration) was in the range of 0.1 to 2.4 mM. However at pH 5 there was a linear increase in the transition concentration with a head-group size due to an increase in steric and electrostatic repulsions between polymer main chains. At pH 9 in the abscence of salt the transition concentration was in the range of 1 to 80 mM. For the larger polymers there was a effect which consisted of a concentration gradient of sodium counterion toward the hydrophobic domain. The effect was larger for the larger polymers because of the higher total sodium concentration and the less steep counterion concentration gradient.

• 대한화학회지
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• 제13권1호
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• pp.1-4
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• 1969

Temperature effect on the critical micelle concentration of hexadecyl trimetyl ammonium bromide over the range of $2^{\circ}-50^{\circ}C$ has been investigated by the method of electrical conductivity. The values obtained have been formulated as a power series in T. Several thermodynamic parameters have been calculated for the temparature range examined and their values have been discussed in the light of current theories on the participation of solvent in micelle formation.

• 대한화학회지
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• 제16권4호
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• pp.201-204
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• 1972

Decylpyridinium Chloride 수용액의 c.m.c를 $10^{\circ}$부터 $50^{\circ}$사이의 온도에서 전기전도도법으로 결정하였던바 온도에 따른 c.m.c. 변화는 $15^{\circ}$근처에서 최소값을 보였다. Clausius-Clapeyron형의 식과 log(c.m.c)의 온도방법식으로 부터 micelle화 과정에 따른 ${\Delta}Hm$, ${\Delta}$Fm^{\circ}$, ${\Delta}$Sm, ${\Delta}Sm^{\circ}$ 및 ${\Delta}$Cpm을 얻어 dodecylpyridinium chloride와 dodecylpyridinium bromide의 값들과 비교 검토하였다.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.2001-2006
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• 2009

Temperature dependence of the critical micelle concentration (CMC), $x_{CMC}$, in micellization can be described by ln $x_{CMC}$ = A + BT + C lnT + D/T, which has been derived statistical-mechanically. Here A, B, C, and D are fitting parameters. The equation fits the CMC data better than conventionally used polynomial equations of temperature. Moreover, it yields the unique(exponent) value of 2 when the CMC is expressed in a power-law form. This finding is quite significant, because it may point to the universality of the thermal behavior of CMC. Hence, in this article, the nature of the equation ln $x_{CMC}$ = A + BT + C lnT + D/T is examined from a lattice-theory point of view through the Flory-Huggins model. It is found that a linear behavior of heat capacity change of micellization is responsible for the CMC equation of temperature.