Sodium perfluorononanoate

Two relaxation processes were evidenced for a large number of surfactants by using two relaxation techniques or, in favorable instances, a single one. Examples of conventional surfactants sodium dodecylsulfate (shock tube (ST) or ultrasonic relaxation (USR) and p-jump - ) sodium tet-radecyl- and hexadecylsulfates (ST and p-jump ) alkylpy-ridinium sulfates (ST and p-jump ) alkylpyridinium halides (ST and p-jump ) alkylammonium halides (ST and p-jump ) surfactants with divalent counterions (T-jump, p-jump, SF ) two-chain surfactants (USR, SF, and p-jump ) nonionic surfactants (T-jump ). Examples of perfluoronated surfactants perfluorononanoate with various counterions (p-jump, T-jump, and SF ). Examples of dimeric surfactants the alkanediyl-a,co-bis(dodecyldimethylammonium bromide) (p-jump and ST °). 

Downer et al. [29,30] used neutron reflection and surface tension measurements to investigate the adsorption of four fluorinated surfactants at the air-water interface. The surfactants used were two single-chain carboxylates, sodium per-fluorononanoate (NaPFN) and sodium 9H-perfluorononanoate, and two doublechain sulfosuccinates, sodium bis(l/ir, lH-perfluoropentyl)-2-sulfosuccinate (DCF4) and sodium bis(lH, IH, 5H, 5/f-octafluoropentyl)-2-sulfosuccinate (DHCF4). The replacement of a terminal fluorine by hydrogen creates a permanent dipole in the hydrophobic chain and consequently, increases the cmc and the limiting surface tension as well. 

The volume change upon micellization reported for lithium perfluorononanoate by La Mesa and Sesta [85], AV = 18 2 mL/mol, corresponds to the value of 20 mL/mol estimated by Sugihara and Mukerjee for sodium perfluorooctanoate [135]. However, the value of 14.2 mL/mol reported by Johnson and Olofsson [132] for lithium perfluorononanoate is considerably lower than the value obtained by La Mesa and Sesta. The V, / = 21.5 1 mL/mol value estimated for perfluorooctanoic acid [88] is higher than that of its sodium salt and ... 

Vinylidene fluoride has been polymerized in the presence of ammonium perfluorooctanoate [301], sodium perfluorooctanoate [302], ammonium perfluo-roisooctanoate [304], or ammonium perfluorononanoate [305]. 

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