Polysulfonic acids

A significantly higher yield of monosulfonic acid was obtained when using SO. Less total sludge and calculated polysulfonic acid were also produced. 

Sulfonic acids may be hydrolytically cleaved, using high temperatures and pressures, to drive the reaction to completion. As would be expected, each sulfonic acid has its own unique hydrolytic desulfonation temperature. Lower alkane sulfonic acids possess excellent hydrolytic stability, as compared to aromatic sulfonic acids which ate readily hydrolyzed. Flydrolytic desulfonation finds use in the separation of isomers of xylene sulfonic acids and other substituted mono-, di-, and polysulfonic acids. 

Sulfonic acid-based azo dyes (qv) and intermediates are characterized by the presence of one or more azo, R—N=N—R, groups. An example of a water-soluble polysulfonic acid-based azo dye (3), where M is a metal, typically Na, for use in ink-jet printers, is shown (75). 

Hydrophobic attractive interactions between a polymer and a small-molecule reactant often occur in reactions carried out in aqueous media [Imanishi, 1979 Morawetz, 1975 Overber-ger and Guterl, 1978, 1979]. Acid catalysis of ester hydrolysis by polysulfonic acids is most... 

Sulfonating agent Monosulfonic acidyidd, % Total sludge yield, % Calculated polysulfonic acid, % Ratio of mono polysulfonate... 

The amount of dye bound at equilibrium decreases with increasing number of sulfonic acid groups in the dye molecule due to increasing hydration. For this reason, mono- and polysulfonated acid dyes should not be used together in combination dyeings. 

With di- and polysulfonic acids, the formation of acid salts is possible, of course, by neutralizing only part of the sulfo groups, and it is conceivable that in some cases these acid salts would be suflBciently insoluble to separate out. However, this is the exception as a rule, the precipitate formed by salting out consists of the neutral salt, even with polysulfonic acids. 

Polysulfonic acid derivatives of monoamines, on the other hand, behave b ke the sulfonic acid derivatives of hydrocarbons usually their acid salts, in which one sulfo group is free and the others are present as alkali metal salts, are salted out quite easily. Monosulfonic acid derivatives of polyamines are, like the free amines, soluble in excess mineral acid (cf. page 33). 

The reaction of di- and polysulfonic acids can usually be carried out so that the replacement of the sulfo groups by hydroxyls takes place stepwise (partial alkali fusion). Thus, phenol-m-sulfonic acid is obtained from benzene-m-disulfonic acid under mild conditions, while resorcinol is formed under more vigorous conditions (see page 144) similarly, naphthalene-l,5-disulfonie acid yields, first, l-naphthol-5-sulfonic acid, then l,5 dihydroxynaphthalene, both valuable azo dye... 

The combinatorial synthesis based on the combination of microfluidics and electropolymerization was realized with a microchip consisting of two areas microfluidic channels for generation of gradient of two substances and a parallel electrochemical reactor with platinum electrodes (Fig. 13.3). The system was tested for synthesis of polyaniline in the presence of polysulfonic acid. The reagent ratio providing the best efficiency of the polymer synthesis was evaluated. 

Rheothik Polymer. [Henkel/Emery] Polysulfonic acid tiiickener, suspending agent, slip agent for lubricants, acid arid alkaline systems. 

The neat polysulfonic acids are not markedly associated in clusters and dissolve in hydrocarbon solvents. However their salts, and in particular the Zn and Pb salts, obtained by neutralization with a saturated solution of the corresponding acetates in a hydrocarbon-isopropanol solution, exhibit a distinctly different behavior indicative of strongly associated domains. This is evidenced by measurements of their melt viscosities, showing a steep increase with sulfonate content already at about 1 mol% sulfonate groups. 

Ampholytes represent complex mixtures of homologous polyamino polycarboxylic or polysulfonic acids with close pi and pK values [135,136]. The differences in pi values represent inter-species differences, while the differences in pA values are related to a single species (intra-species differences). Usually the following ranges of pH are covered 3.5-10.0, 2.0-4.0, 3.5-5.0, 4.0-6.0, 5.0-7.0, 5.0-8.0, 6.0-8.0,... 

In water, the solubility of most of synthetic PEs (e.g. PMAA or polysulfonic acid) depends strongly on the presence of ionized groups. In other words, the monomers of most synthetic PEs are often intrinsically hydrophobic [143]. 

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