Cetyl alcohol, structure

Ceroplastol synthesis, 1, 428 Cetyl alcohol synthesis, 1, 478 Chaetoglobasins structures, 4, 376 Chalcone, o -azido-2 -oxy-synthesis, 3, 823 Chalcone, 2-hydroxy-reduction, 3, 751 Chalcone, 2 -hydroxy-mass spectra, 3, 618 Chalcone dibromides flavone synthesis from, 3, 823 Chalcones polymers, 1, 304 Chanoclavine synthesis, 6, 423 Charge density waves in stacks of ions, 1, 351-352 Chartreusin... 

Spermaceti, a fragrant substance from sperm whales, was much used in cosmetics until it was banned in 1976 to protect the whales from extinction. Chemically, spermaceti is cetyl palmitate, the ester of cetyl alcohol (u-ClrtH33OH) with palmitic acid. Draw its structure. 

Figure 13.11.1 The molecular structure of cetyl alcohol or hexadecanol.

Figure 12.2 Structure of waxes. The general structure of a wax is shown in which n and m are usually between 8 and 18. The structure of hexadecyl hexadecanoate (cetyl palmitate), a wax found in sperm whale oil, is shown. This is an ester of hexadecanoic (palmitic) acid and hexadecanol (cetyl alcohol).

Structure Forming Excipient An excipient which participates in the formation of the structural matrix which gives an ointment, cream or gel etc., its semisolid character. Examples are gel fonning polymers, petrolatum, certain colloidal inorganic solids (e.g., bentonite), waxy solids (e.g., cetyl alcohol, stearic acid), and emulsifiers used in creams. 

Cetyl alcohol, C16H33OH, is a common ingredient of soaps and shampoos. It was once commonly obtained from whale oil, which is where it gets its name cetylis derived from cetacean). Draw the chemical structure for this compound. 

With cetyl alcohol, there is the complication that the polarity of the molecule may cause it to reside at the surface of the droplet, imparting additional colloidal stability. Here, the surfactant and costabilizer form an ordered structure at the monomer-water interface, which acts as a barrier to coalescence and mass transfer. Support for this theory lies in the method of preparation of the emulsion as well as experimental interfacial tension measurements [79]. It is well known that preparation of a stable emulsion with fatty alcohol costabilizers requires pre-emulsification of the surfactants within the aqueous phase prior to monomer addition. By mixing the fatty alcohol costabilizer in the water prior to monomer addition, it is believed that an ordered structure forms from the two surfactants. Upon addition of the monomer (oil) phase, the monomer diffuses through the aqueous phase to swell these ordered structures. For long chain alkanes that are strictly oil-soluble, homogenization of the oil phase is required to produce a stable emulsion. Although both costabilizers produce re-... 

Y. Kakiuchi. Proc. Japan Acad. 23, 65-8 (1947) (in English). Crystal structure and electric properties of stearic acid and cetyl alcohol. 

Williams and Lawton have presented a graphical comparison of the equivalent torsion angles in the 12-membered central ring of TOT for three different crystalline species the ethanol and n-cetyl alcohol TOT inclusion compounds, and the unsolvated TOT. This comparison was instructive because it revealed a fairly consistent molecular deformation in three different crystalline environments. A rationale for this structural feature is not readily apparent. 

Ribeiro HM, Morals JA, Eccleston GM. Structure and rheology of semisolid o/w creams containing cetyl alcohol/non-ionic surfactant mixed emulsifier and different polymers. Int J Cosmet Sci. 26(2)... 

The ternary system consisting of the anionic surfactant sodium dodecyl sulfate (SDS), 1-hexadecanol (cetyl alcohol, CA), and D2O was used as an example for structural investigations with different methods [16, 19]. The corresponding system... 

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