Tetradecylpyridinium

Fig. 6, Variation of the reciprocal of the relaxation time T2 for the micelle formation-dissolution process upon addition of pentanol to O.IM TTAB (+) and O.lM tetradecylpyridinium bromide ( ) solutions in water at 25°. (The measurements were performed by means of T-jump Eosine was used as a probe for the relaxation process in TTAB solutions (see C. Tondre, J. Lang and R. Zana, J. Colloid Interface Sci., 52, 372 (1975).)...

Qi, Z. Yao, J. Chen, H. The cocoloration system of alkahne earth(II)-rare earths(III)-alizarine violet-tetradecylpyridinium chloride. Beijing Keji Daxue Xuebao 1989, 11, 486-491 Chem. Abstr. 1991, 114, 73971. 

FIG. 22 Enthalpy of wetting for different masses of hydrophobic montmoriUonites— (1) Tetradecylpyridinium and (2) hexadecylpyridinium montmoriUonites in methanol and (3) octadecylpyridinium and (4) dimethyldioctadecylammonium montmoriUonites in toluene. 

There is a lot of literature so far on the study of hydro-phobic interaction of ethyl(hydroxyethyl)cellulose (EHEC) with various ionic surfactants in water. The techniques used in these studies are of electromotive force of N-tetradecylpyridinium bromide [1], of thermal gelation with sodium dodecylsulfate (SDS) [2], of Fourier transform NMR in the presence of dodecyltrimethylammonium bromide [3], of phase separation diagram with various kinds of anionic and cationic surfactants [4], and so on. These studies have focused on the complex formation between EHEC and these surfactants and on the concomitant phase separation of the polymer solution. 

Adsorption of ionic surfactants on to polar substrates will be affected by pH. The relationship between the amount of NaDS adsorbed on to colloidal alumina and the stability ratio, W, of alumina dispersions is shown in Fig. 9.5 at two different pH values, 6.9 and 1,2, The zero point of charge of alumina is pH 9.1 thus the higher surface charge at pH 6.9 ensures that hydrocarbon chain interactions occur at a lower surfactant concentration than at pH 7.2. As the pH is lowered further this effect is accentuated [12]. The effect of pH on adsorption of lauryl sulphate ions and tetradecylpyridinium ion is shown clearly in Rupprecht s [6] results using colloidal titanium dioxide as the adsorbate (Fig. 9.6). 

Tetradecylpyridinium chloride X - X - X Cetylpyridinium chloride Octadecylpyridinium chloride... 

Figure 3.10 Tetradecylpyridinium bromide effect of additions of KBr on the value of AHg, activation enthalpy of l/t2, at surfactant concentration 8 mM (+) 2 mM (O) and 1.2 mM (A). ( ) Value in the absence of KBr. The broken vertical lines indicate the limiting values of AH2 obtained from nonlinear variations of l/t2 with 1/T. Reproduced from Reference 90 with permission of Elsevier/Academic Press.

Alkylpyridinium cations can be used instead of akylammonium for the fabrication of LB films. For example, docosyl- and tetradecylpyridinium[Ni(dmit)2] (abbreviated as C22PyNi(dmit)2 and Ci4PyNi(dmit)2, respectively) LB films mixed 1 1 with arachidic acid showed conductivities of 0.3 and 1.2 S/cm after electrochemical oxidation [203]. 

---