New self-assembling systems based on bola-type pyrimidinic surfactants.
New amphiphilic pyrimidinic (AP) compounds with two ammonium head groups and different kinds of counterions, inorganic bromide anions (APB) and hydrophobic tosylate anions (APT) were synthesized. Self-organization in these systems has been studied by methods of tensiometry, conductometry, potentiometry and NMR spectroscopy. The critical micelle concentrations (cmc's) of bola-type surfactants are only a little lower than those of cetyltrimethylammonium (CTA) analogues. For both pairs APB/CTAB and APT/CTAT the counterion binding is stronger for the conventional cationic surfactants as compared to 'bola' pyrimidinic surfactants. Unlike the CTAT micelles no sharp micellar growth occurs with the APT concentration. The geometry of AP compounds is assumed to be mainly responsible for the above finding. A branched molecular architecture prevents a close packing of the monomers in the bulk solution and at the interface producing a steric hindrance around the head groups.
Zakharova
Lucia
L
A.E. Arbuzov Institute of Organic and Physical Chemistry of the Russian Academy of Science, Ul. Akad. Arbuzov 8, 420088 Kazan, Russia. lucia@iopc.knc.ru
Syakaev
Victor
V
Voronin
Mikhail
M
Semenov
Vyacheslav
V
Valeeva
Farida
F
Ibragimova
Alsu
A
Bilalov
Azat
A
Giniyatullin
Rashit
R
Latypov
Shamil
S
Reznik
Vladimir
V
Konovalov
Alexander
A
D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D004058:Diffusion; D004553:Electric Conductivity; D008823:Micelles; D011726:Pyridinium Compounds / Q000737:chemistry*; D013500:Surface Tension; D013501:Surface-Active Agents / Q000737:chemistry*
D002593:Cetrimonium Compounds; D008823:Micelles; D011726:Pyridinium Compounds; D013501:Surface-Active Agents; C020810:trimethylcetylammonium p-toluenesulfonate; D000077286:Cetrimonium