Surface Activity And Adsorption Of Some ‎Surfactants At Aqueous / Air Interface At ‎Different Temperatures

The adsorption of a series of ethoxylated nonionic and anionic ‎surfactant molecules at aqueous / air interface at different temperature ‎ranges [298, 308, 318, 328 and 338K] was studied. Different surface ‎parameters were evaluated from surface tension measurements at ‎different temperatures. The effectiveness of adsorption, Гmax, for all ‎nonionic and anionic surfactants was discussed with respect to their ‎hydrophilic and hydrophobic characters. Ethoxylated stearate had the ‎lowest effectiveness of adsorption at 298K comparing to other ‎nonioics. Minimum surface area per molecule, Amin, was calculated ‎which provides information on the degree of packing and orientation ‎of the adsorbed surfactant molecules. Amin decreased through ‎increasing the hydrophobicity. Also, the effectiveness of surface ‎tension reduction, πcmc was discussed concerning on surfactant ‎structures. The dependence of surface parameters (Гmax and Amin) on ‎temperatures was explained in details. For the most investigated ‎nonionic and anionic surfactants πcmc were slightly affected by ‎temperature.‎

REFERENCES

[1] M.J.‎ Rosen, Surfactants and Interfacial phenomena. John Wiley & Sons, New York (1978).

[2] A.A.‎ El-Feky; M.N.‎ Shalaby; O.A.A. ‎El-shamy, Polymers as hydrophobic adsorbents surface for some surfactants. J. Dispersion Sci. and Technology, 30(4), (2009).

[3] K. Elissa, �An Overview of Decision Theory," unpublished. (Unplublished manuscript)

[4] R. Nicole, "The Last Word on Decision Theory," J. Computer Vision, submitted for publication. (Pending publication)

[5] C. J. Kaufman, Rocky Mountain Research Laboratories, Boulder, Colo., personal communication, 1992. (Personal communication)

[6] D.S. Coming and O.G. Staadt, "Velocity-Aligned Discrete Oriented Polytopes for Dynamic Collision Detection," IEEE Trans. Visualization and Computer Graphics, vol. 14, no. 1, pp. 1-12, Jan/Feb 2008, doi:10.1109/TVCG.2007.70405. (IEEE Transactions )

[7] S.P. Bingulac, �On the Compatibility of Adaptive Controllers,� Proc. Fourth Ann. Allerton Conf. Circuits and Systems Theory, pp. 8-16, 1994. (Conference proceedings)

[8] H. Goto, Y. Hasegawa, and M. Tanaka, �Efficient Scheduling Focusing on the Duality of MPL Representation,� Proc. IEEE Symp. Computational Intelligence in Scheduling (SCIS �07), pp. 57-64, Apr. 2007, doi:10.1109/SCIS.2007.367670. (Conference proceedings)

[9] J. Williams, �Narrow-Band Analyzer,� PhD dissertation, Dept. of Electrical Eng., Harvard Univ., Cambridge, Mass., 1993. (Thesis or dissertation)

[10] E.E. Reber, R.L. Michell, and C.J. Carter, �Oxygen Absorption in the Earth�s Atmosphere,� Technical Report TR-0200 (420-46)-3, Aerospace Corp., Los Angeles, Calif., Nov. 1988. (Technical report with report number)

[11] L. Hubert and P. Arabie, �Comparing Partitions,� J. Classification, vol. 2, no. 4, pp. 193-218, Apr. 1985. (Journal or magazine citation)

[12] R.J. Vidmar, �On the Use of Atmospheric Plasmas as Electromagnetic Reflectors,� IEEE Trans. Plasma Science, vol. 21, no. 3, pp. 876-880, available at http://www.halcyon.com/pub/journals/21ps03-vidmar, Aug. 1992. (URL for Transaction, journal, or magzine)

[13] J.M.P. Martinez, R.B. Llavori, M.J.A. Cabo, and T.B. Pedersen, "Integrating Data Warehouses with Web Data: A Survey," IEEE Trans. Knowledge and Data Eng., preprint, 21 Dec. 2007, doi: 10.1109/TKDE.2007.190746.(PrePrint).