Effect of Counter-Ion

Kagawa, I. Gregor, H. P. (1957). Theory of the effect of counter ion size upon titration behavior of polycarboxylic acids. Journal of Polymer Science, 23, 477-84. 

Ab initio MO studies on the ordering of Si and A1 atoms in zeolite frameworks and on the stabilizing effects of counter ions... 

Two further innovations are the consideration of polymerisations in which the kinetic order with respect to monomer may be different from unity, and that the very common alleged effects of counter-ions might be due to a concurrent pseudo-cationic (cationoid insertion) polymerisation. 

There are many papers which purport to record the effect of counter-ion on such factors as transfer constants, co-polymerisation ratios, etc. It is significant that in most of these studies relatively high initiator concentrations have been used, so that counter-ion effects are more likely but before accepting that the observed effects are indeed due to change of counter-ion (derived from different catalysts or co-catalysts) it must be ascertained that these polymerisations are in fact cationic and not pseudo-cationic - in which case the effects would stem from the different reactivities of different esters (see Section 5). 

Figure 2. Representation of the possible site forms in the site-binding model which includes the effect of counter-ion adsorption, combined with a diagram of charges and potentials at the insulator/electrolyte interface. Reproduced with permission from Ref. (14). Copyright 1983, North Holland.

Figure 4.12 Effect of counter-ions and copper on the retention of amino acids. Column, octadecyl-bonded silica gel, 25 cm x 4.6 mm i.d. eluent, 0.01 M sodium acetate buffer (pH 5.6) containing 1.2 mM sodium octanesulfonate (Oc) andj or 0.1 mM copper acetate (Cu) flow rate, 1ml min-1 detection, UV 220 nm. Compounds Glu, glutamic acid, Asp, aspartic acid.

A. Bartha, H.A.H. Billiet, L.D. Galan, and G. Vigh, Studies in reversed-phase ion-pair chromatography III. The effect of counter-ion concentration , J. Chromatogr., 1984, 291,91. 

S.O. Jansson, Effect of counter-ions in ion-pair liquid chromatography of hydrophobic amines on non-polar bonded phases , J. Liq. Chromatogr., 1982, 5, 677. 

Except in very special circumstances (Section 6.4) electroneutrality is maintained in cationic polymerizations by the presence of a negatively charged counter-ion or gegenion, X . This species has no analogue in free radical polymerizations, and indeed much of the early work on cationic (and anionic) reactions was carried out with almost total disregard for the effect of counter-ion. In fact it turns out as we shall see that the counter-ion, and its physical relationship with the growing cation, is of vital importance in the interpretation of kinetic data derived from these systems. The present authors take the view that, while results obtained from polymerizations where such relationships are unknown are qualitatively useful, any quantitative data obtained must be treated with caution. 

Figure 14 The effect of counter-Ion on flux and separation factor of a Naflon hollow fiber.

Waldron-Edward D, Paul TM, Skoryna SC. 1966. Effects of counter ion and pH on intestinal absorption of calcium and strontium. Proc Soc Exp Biol Med 123(2) 532-538. 

K. Onishi, S. Sewa, K. Asaka, N. Fujiwara and K. Oguro, The effects of counter-ions on characterization and performance of a solid polymer electrolyte actuator, Electrochim. Acta, 2001, 46, 1233-1241. 

Szabo G.T., More Gy. Ramadan Y. (1996), Filtration of organic solutes on reverse osmosis membrane. Effect of counter-ions. Journal of Membrane Science, 118, 295-302. 

On the other hand, p-type doped polymers may be expected to be stable but prone to the degradative effect of counter-ions. Druy el al. [29] demonstrated the counter-ion dependence of initial electrical conductivity loss in polyacetylene where the electrical conductivities of the samples doped with I2 and CIO4 were maximally affected, due to the strong oxidizing ability of these dopants. Somewhat complementary results have also been reported by various other workers [30-32]. 

Hoberg, A.-M., Haddleton, D. M., Derrick, P. J., Jackson, A. T., and Scrivens, J. H., The Effect of Counter Ions in Matrix-assisted Laser Desorption/Ionization of Poly(methyl methacrylate), Eur. Mass. Spectrom., 4, 435,1998. 

In the case of Brpnsted acid-mediated glycosyl fluoride donor glycosylations, the effect of counter-ion was also found to be as important as that of solvent [21]. For instance, trifluoromethanesulfonic acid favoured the formation of the a-glycoside, whereas bis-trifluoromethanesulfonamide favoured p. Interestingly, this phenomenon was emphasised by the demonstration of matched and mismatched selectivities... 

Zeta potential depends on many solution and substrate parameters, such as pH, counterions concentration, valence and size, temperature, substrate material and its surface properties, etc. [30,31]. Strong effect on the i -potential has the valence and concentrations of applied electrol5hes [30]. Therefore some of authors tested various electrolytes and different electrolyte concentrations [39]. The effects of counter-ion valence and size do not play role in the case of potassium and sodium ions, differences being small for silica and also polymer substrates and are only important in cases where larger ions dominate the counter-ion concentration [30,31]. The bivalent cations exhibit specific adsorption which can be ignored for monovalent cations, such as Li, Na and K [30]. It can be concluded that monovalent cations are more suitable and there are no significant differences between e.g. KCl and NaCl. Therefore we used KCl and KNOs for our studies. 

Trinh TT, Jansen APJ, van Santen RA, VandeVondele J, Meijer EJ (2009) Effect of counter ions on the silica oligomerization reaction. ChemPhysChem 10 1775—1782. 

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