Conductivities of Quaternary Ammonium Chlorides Containing Two Long-chain Alkyl Groups

Alkanediyl-α,ω-bis(dimethylalkylammonium bromide) Surfactants

“…The upward curvature in the K vs C plot and the maximum in the vs C 0.5 seen with 16-8-16 are no longer present with HBDMAB, indicating the absence of premicellar association for this surfactant. The presence of a maximum was reported long ago in the vs C 0.5 plots for some dialkyldimethylammonium chlorides (alkyl = dodecyl, tetradecyl, and hexadecyl) and attributed to premicellar association (29). For our part we have observed at C < cmc a maximum in the vs C 1/2 plot for didocyldimethylammonium bromide and also for 12-12-12, 12-14-12, 12-20-12, and 16-6-16 (results not shown), in addition to 16-8-16 (Fig.…”

“…For the contribution of the micelles to the conductivity of the solution, this method uses an expression that is very similar to that in Eq. [29] in Ref. (17) Table 1.…”

Phase Transition Behavior and Permeation Properties of Cationic and Anionic Artificial Lipids with Two Alkyl Chains

“…The influence of side and consecutive reactions has been investigated in a computer simulation of the reaction system. -The final result for the rate constant of reaction (1) is k t (296 K) = (8.1 ± 3.0) . 10 13 cm 3/mol s .…”

“…The reaction (1) has been studied at room temperature in an isothermal discharge flow reactor. Methylene-radicals and oxygen-atoms have been monitored with a Far-Infrared Laser Magnetic Resonance spectrometer.…”

“…This amphiphatic character and the hydrophilic-hydrophobic balance must be taken into consideration to synthesize the totally artificial lipids which have membrane structures and permeation properties similar to those of biological membranes. Ralston et al studied the amphiphatic behavior of quarternary ammonium salts with two long alkyl chains [1). They suggested that the simple positivelycharged hydrophilic moiety was sufficient to form bimolecular lamellae instead of complicated polar head groups of biological phospholipids.…”