Strong polyacid

Polyelectrolyte complex Strong polyacid-Strong Conductivity, Potentiometry, 1/1 Specific ternary... 

Strong polyacid-Weak Sedimentation, Diffusion, 1/1 1/5 High pH. High id... 

Information about physicochemical and complexation properties of polyvinylsulfonic acid (PVSH) or, more correctly, polyethylenesulfonic acid (PESH) [11] is much less available than that of the polyamines. PVSH (or PESH) is a simple, strong polyacid (see Fig. 6.6), so that partial ionization and possible hydrolysis effects, encountered with weak polyacids and their salts (e.g., polyacryfic acid and its salts), do not complicate the picture [76]. Commercially available sodium salt, PVSNa, is a brittle hygroscopic solid, soluble in water, but insoluble in organic solvents (methanol, dioxane, etc.) [77]. Viscosity behavior of the alkali metal salts was studied by several groups [28, 52, 75-77], but data are too scattered to be trustworthy. The PVS polyanion shows a definite selectivity in ion binding with alkali Li, Cs metals in the presence of Na, K hah des [78]. 

Figure 2 shows also the relationship between [ii] and pH of MGC and PVSK, a strong polybase and strong polyacid, respectively. Linear curves... 

When freshly mixed, the carboxyHc acid groups convert to carboxjiates, which seems to signify chemical adhesion mainly via the calcium of the hydroxyapatite phase of tooth stmcture (32,34—39). The adhesion to dentin is reduced because there is less mineral available in this substrate, but bonding can be enhanced by the use of minerali2ing solutions (35—38). Polycarboxylate cement also adheres to stainless steel and clean alloys based on multivalent metals, but not to dental porcelain, resin-based materials, or gold alloys (28,40). It has been shown that basic calcium phosphate powders, eg, tetracalcium phosphate [1306-01-0], Ca4(P0 20, can be substituted for 2inc oxide to form strong, hydrolytically stable cements from aqueous solution of polyacids (41,42). 

H-Bonding, Strongly Associative (HBSA) Water Primary amides Secondary amides Polyacids Dicarboy lic acids Monohydro) acids Polyj)henols Oximes Hydroj laniines Amino alcohols Polyols... 

It is well known that lyophilic sols are coagulated by the removal of a stabilizing hydration region. In this case, conversion of a sol to a gel occurs when bound cations destroy the hydration regions about the polyanion, and solvated ion-pairs are converted into contact ion-pairs. Desolvation depends on the degree of ionization, a, of the polyacid, and the nature of the cation. Ba ions form contact ion-pairs and precipitate PAA when a is low (0-25), whereas the strongly hydrated Mg + ion disrupts the hydration region only when a > 0-60. 

In solutions, the counterions of poly electrolytes are HjO (for the polyacids) and OH (for the polybases), cations such as K+ and Na, or anions such as Cl (for the polysalts). The addition of polyvalent counterions (such as Ca, Mg, Cu, AT ) produces ionic cross-linking interfering with solubility The polyelectrolyte precipitates and may be redissolved upon addition of a strong acid (such as HCl). This can be regarded as a special case of ion exchange. 

Regardless of classification, polysaccharides express varying degrees of ethanol tolerance neutral species are mostly unresponsive to electrolytes, including weak acid, and protonated species precipitate with low solvent retention from strong acid and Ca2+ solutions. Exceptions to many general rules abound for example, polyacids are generally the most stable species,... 

Weak polyacid-Strong scattering, Turbidity, IR 9/1 1/1 Low pH, High p... 

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