Effects of the structure of anionic polyelectrolytes on surface potentials of their aggregates in water

Autor: I. A. Pastre, O. A. El Seoud, Miguel G. Neumann, Ana M. Chinelatto
Rok vydání: 1996
Předmět:
Zdroj: Colloid and Polymer Science. 274:475-481
ISSN: 1435-1536
0303-402X
DOI: 10.1007/bf00652471
Popis: The surface potential, ψ in mV, was determined for the following polyelectrolytes and co-polyelectrolytes in aqueous solution: sodium poly(styrene sulfonate); sodium poly(vinyl sulfonate); poly(vinyl alcohol-co-55% sodium vinyl sulfate); poly(methylmethacrylate-co-40% sodium styrene sulfonate); poly (methylmethacrylate-co-60% sodium styrene sulfonate); poly(styrene-co-56% styrene sulfonate); and poly(styrene-co-80% styrene sulfonate). For comparison, the surface potentials of aqueous sodium dodecyl sulfate and sodium dodecylbenzene sulfonate micelles were also determined. The dyes neutral red and safranine-T were used as indicators. ThepKa of the former was calculated from the Henderson-Hasselbach equation, using UV-VIS spectroscopy to determine the concentration of protonated ground state as a function of pH. The surface potential of the aggregates was culculated from the equation: $$pKa_{\text{i}} = pKa_0 - {{F\Psi } \mathord{\left/ {\vphantom {{F\Psi } {2.3RT}}} \right. \kern-\nulldelimiterspace} {2.3RT}}$$
Databáze: OpenAIRE
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