Chemistry:Alpha-olefin sulfonate
thumb|right|General chemical structure of α-olefin sulfonates
R= Alkyl, M= Na+, n = 1 or 2
α-Olefin sulfonates (AOS) are a group of anionic surfactants, which are used as detergents.[1] The compounds contain a - mostly linear, primary - alkyl R and a monovalent cation M, preferably sodium.[2] The most frequently used example of this group of substances is sodium α-olefin sulfonate (INCI: Sodium C14-16 Olefin Sulfonate).[3]
Production and composition
α-Olefin sulfonates are produced by sulfonation of alpha-olefins, typically using sulfur trioxide. Subsequent alkaline hydrolysis gives a mixture of alkene sulfonates (60-65%) and hydroxyalkane sulfonates (35-40%). The commercially available olefin sulfonates are mostly solutions with about 40% active ingredient content.[4][5]
Description
In addition to a longer hydrocarbon chain in which there must be at least one double bond (hence the name "olefin"), it has an anionic sulfonate headgroup with a sodium ion as a counterion. The sulfonate group is negative in aqueous solution, which is why the α-olefin sulfonates are among the anionic surfactants. In contrast to most other surfactants in which the C12-alkyl chains have the highest surface activity, olefin sulfonates shows maximal activity when using C14and C16-olefins.[4]
Usage
α-Olefin sulfonates with linear alkenyl radicals from C12 to C18 are used as anionic surfactants in various areas of application due to their pronounced foam formation[clarification needed] and foam stability (even with high water hardness), excellent fat-dissolving power and oil dissolving power as well as a favorable ecological profile and low aquatic toxicity and human toxicity.[6][7] They are being used for example in detergents and cleaning agents, for degreasing, in the emulsion polymerization, the conditioning of concrete and mortar as well as in the formulation of pesticides.[2]
In some shampoos sodium C14-16 olefin sulfonate is being introduced as an alternative for sodium laureth sulfate without sulfate. Some groups and sellers suggest that it is better for someones health, but for this claim is no evidence.[8]
References
- ↑ Raney, Kirk H.; Shpakoff, Paul G.; Passwater, Deborah K. (1998). "Use of high-active alpha olefin sulfonates in laundry powders" (in en). Journal of Surfactants and Detergents 1 (3): 361–369. doi:10.1007/s11743-998-0037-z. ISSN 1558-9293. https://aocs.onlinelibrary.wiley.com/doi/abs/10.1007/s11743-998-0037-z.
- ↑ 2.0 2.1 Entry on α-Olefin Sulfonate. at: Römpp Online. Georg Thieme Verlag, retrieved 6 July 2019.
- ↑ External identifiers of or database links to Sodium C14-16 olefin sulfonate: CAS-Number: 68439-57-6, EC Number: 270-407-8, ECHA-InfoCard: 100.063.987, Wikidata: Q72507735.
- ↑ 4.0 4.1 Williams, D. F.; Schmitt, W. H. (1996). Chemistry and Technology of the Cosmetics and Toiletries Industry (Second ed.). Dordrecht: Springer Netherlands. pp. 6. ISBN 978-94-009-1555-8. OCLC 840304608. https://www.worldcat.org/oclc/840304608.
- ↑ Marquis, D. M.; Sharman, S. H.; House, R.; Sweeney, W. A. (November 1966). "Alpha olefin sulfonates from a commercial SO 3 -Air reactor" (in en). Journal of the American Oil Chemists' Society 43 (11): 607–614. doi:10.1007/BF02640797. http://doi.wiley.com/10.1007/BF02640797.
- ↑ Nair, Bindu (1998-10-01). "Final Report On the Safety Assessment of Sodium Alpha-Olefin Sulfonates" (in en). International Journal of Toxicology 17 (5_suppl): 39–65. doi:10.1177/109158189801700504. ISSN 1091-5818. https://doi.org/10.1177/109158189801700504.
- ↑ "Re-Review of Sodium α-Olefin Sulfonates as Used in Cosmetics | Cosmetic Ingredient Review". https://www.cir-safety.org/panelbook/re-review-sodium-%CE%B1-olefin-sulfonates-used-cosmetics.
- ↑ Cline, A.; Uwakwe, L.N.; McMichael, A.J. (January 2018). "No sulfates, no parabens, and the "no-poo" method: a new patient perspective on common shampoo ingredients" (in en). Cutis 101 (1): 22–26. PMID 29529111. https://pubmed.ncbi.nlm.nih.gov/29529111/.
 |
