Kinetic analyses of gegenion binding in polyelectrolyte solution. Cationic phosphorescence probe and poly(styrenesulfonate) anion system

Abstract

The kinetics of binding between sodium poly(styrenesulfonate) (NaPSS) and cationic phosphorescence probes have been studied by phosphorescence decay methods. The probes (Scheme I) are rc-(4-bromo-lnaphthoyl)methyl-(or pentyl, decyl) trimethylammonium bromide (BNK-1+, BNK-5+, and BNK-10"1" for n = 1, 5, and 10, respectively). From a method involving phosphorescent quenching for the BNK-1+ and NaPSS systems, the association (kf) and dissociation rates (kh) are evaluated as 6.8 X 109 M™1 s"1 and 3.7 X 104 s"1.The magnitude of k{ is close to the limit for diffusion-controlled quenching, which demonstrates that the probes are not bound via "site binding", but rather via "atmospheric binding". The magnitudes of ks and the equilibrium association constant, K, decrease with NaCl addition or with increasing polymer concentration, whereas kh increases. The results of these kinetics are consistent with Manning's theory of polyelectrolyte systems.

A Tr Esr study of the quenching of photoexcited dioxouranium (VI) salts by stable nitroxyl free radicals

“…The relatively small D z of uranyl may be one of the reasons for the need for protracted contact of UO22+' with r for the creation of CIDEP. The strong effect of the binding of ionic reagents to polyetectrolytes in enhancement of photoinduced electron transfer and excited states quenching was clearly demonstrated in references [7,[15][16][17]19]. The present results show that such binding facilitates the formation of CIDEP.…”

“…It is known that uranyl is bound to anionic polyelectrolytes [15]. We propose that TEMPO +, as a compound with a positively charged tetramethylammonium group, is also concentrated in the vicinity of the polyanion [16]. Thus, the polyanion assists the creation (or transfer) of polarization under an interaction of uranyl and TEMPO +.…”

Optical Properties of Polyelectrolytes

“…Phosphorescence measurements have not received as much attention in this respect although examples are available [6][7][8][9][10][11][12][13][14][15]. Phosphorescence measurements have not received as much attention in this respect although examples are available [6][7][8][9][10][11][12][13][14][15].…”

The Effect of Microheterogeneous Domains in the Protonation of the Triplet State of Safranine-T

“…Little changes were observed for the pK a of the triplet r eff Å r C /[exp(r C /r AB ) 0 1], [7] state when Safranine is dissolved in solutions containing micelles or polyelectrolytes. For PSS, the value increases where r AB is the interaction radius for noncharged reactants less than 1.0 pK unit.…”

“…and micelles. These results are important for ascertaining Besides, polyelectrolytes are good models for proteins and the proton concentration effects of the microheterogeneous other entities of biological interest (6)(7)(8)(9)(10)(11). Like systems domains, and should be of use for understanding the potential composed of ionic surfactants, polyelectrolytes will originate catalytic properties of those compounds.…”