Polyelectrolytes anionic polysoaps

In the case of the anionic esters, the alkaline hydrolysis of NDBS and NABS are enhanced by the addition of cationic polyelectrolyte and polysoap. The most hydrophobic catalyst (PVII-C16) gave the largest enhancement for both substrates. Saturation behavior was observed for both anionic substrate reactions, indicating the formation of the complex between polymer and substrate (20). In the case of the NABS, the increase in the hydrophobic character of the catalysts yields a very small increase in both the binding constant (K) and k2 and thus it can be concluded that the hydrophobic interaction plays a very minor role. 

Varoqui, R., Strauss, U.P. Comparison of electrical transport properties of anionic polyelectrolytes and polysoaps. J. Phvs. Chem. 1968, 72 (7), 2507-2511. 

We have initiated a series of investigations to study the catalytic effects of a class of cationic polyelectrolytes ranging in solution behavior from "normal" polyions to polysoaps upon the alkaline hydrolysis of neutral and anionic phenyl esters of varying chain lengths. Employing these catalysts of varying hydrophylic-hydrophobic character in reactions of neutral and anionic substrates of varied hydrophilic-hydrophobic character, it should be possible to elucidate the contributions of both the hydrophobic interactions and electrostatic interactions on the rate of reaction. 

As discussed before, the borderline between polysoaps and polyelectrolytes or thickeners is determined by the hydrophilic-hydrophobic balance HLB, as well as by the length and the density of the hydrophobic tails chosen. The longer they are, the lower is the content of hydrophobic tails - the Critical Alkyl Group Content CAC [52, 75] - needed in order to produce polysoap behaviour (cf. Sect. 2.3.2). For poly(2-vinylpyridine) and poly(4-vinylpyridine), about 20% of derivatization with octyl tails and about 10% of derivatization with dodecyl tails are needed as a minimum to obtain the characteristic low viscosities [49, 52, 75, 133, 141, 317] (Fig. 17). Comparable CAC values are obtained for derivatized poly(vinyl-imidazol)s [140] and for poly(allylamine)s [152]. Similarly in anionic copolymers of poly(sodium 2-acrylamido-2-... 

Water-soluble polymers possessing ionic groups along or pendent to the backbone are one of die most important classes of macromolecules, ranging from biopolymers such as polynucleotides to commercially important viscosifiers and polysoaps. These polymers are often classified into two groups polyelectrolytes with either anionic or cationic fimctionality and polyampholytes that possess both. 

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