[article]
Titre : |
Synthesis and surface properties of CO2H type gemini surfactant having semifluoroalkyl group as hydrophobic group |
Type de document : |
texte imprimé |
Auteurs : |
Tokuzo Kawase, Auteur ; Tomoyuki Ankyu, Auteur ; Tatsuo Oida, Auteur |
Année de publication : |
2012 |
Article en page(s) : |
p. 498-507 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Surfactants
|
Index. décimale : |
668.1 Agents tensioactifs : savons, détergents |
Résumé : |
Novel CO2H type gemini surfactants having semifluoroalkyl group (Rf-(CH2)n-: Rf = C4F9, C6F13, C8F17 and n = 2, 3) as hydrophobic group were successfully synthesized and their surface properties were studied. (Perfluoroalkyl)ethylmalonic esters were synthesized by the reaction of malonic ester with Rf(CH2)2I using NaH as base in THF/DMF. (Perfluoroalkyl)propylmalonic esters were synthesized from allylmalonic ester, namely by the radical addition of Rf-I using AIBN as initiator, and reduction with Zn/AcOH. Those fluoroalkylated malonic esters were connected using Br(CH2)sBr (s = 3, 4) to give dimeric tetraesters. Then, tetraesters were hydrolyzed using KOH/EtOH followed by decarboxylation in AcOH to afford CO2H type gemini surfactants. To study their surface properties, both surface tension-concentration and surface pressure-area isotherms were measured. As expected, COOH geminis showed one order of magnitude lower critical micellar concentrations (CMC) than that of conventional 1+1 type surfactant. In the surface pressure-area measurements, as length of fluoroalkyl increased, lift-off area (AL) decreased, monolayers were clearly formed upon compression and the limited areas (A?) for C6F13 and C8F17 were smaller than twice of that of C8F17(CH2)2COOH. Especially, COOH geminis having Rf = C8F17 and -(CH2)3- spacer showed the formation of solid phase monolayers, and the planar five membered ring-like structure was proposed. |
Note de contenu : |
- EXPERIMENTAL : Materials and instruments - Synthesis of COOH type gemini - Measurements
- RESULTS AND DISCUSSION : Synthesis of fluoroalkylmalonic ester - Surface properties of COOH type gemini |
DOI : |
10.3139/113.110223 |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=16538 |
in TENSIDE, SURFACTANTS, DETERGENTS > Vol. 49, N° 6 (11-12/2012) . - p. 498-507
[article]
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