Polystyrene sulfonate diffusion coefficient

Th-FFF can be applied to almost all kinds of synthetic polymers, like polystyrene, polyolefins, polybutadiene, poly(methyl methacrylate), polyisoprene, polysulfone, polycarbonate, nitrocelluloses and even block copolymers [114,194,220]. For some polymers like polyolefins, with a small thermal diffusion coefficient, high temperature Th-FFF has to be applied [221]. Similarly, hydrophilic polymers in water are rarely characterized by Th-FFF, due to the lack of a significant thermal diffusion (exceptions so far poly(ethylene oxide), poly(vi-nyl pyrrolidone) and poly(styrene sulfonate)) [222]. Thus Th-FFF has evolved as a technique for separating synthetic polymers in organic solvents [194]. More recently, both aqueous and non-aqueous particle suspensions, along with mixtures of polymers and particles, have been shown to be separable [215]. 

The (idealized) radius of a polystyrene styrene sulfonate may be several hundred angstroms. Were you to measure the self-diffusion coefficient, what equation would you use to obtain a measure of the ion s size Explain the principles (showing appropriate equations) of obtaining an individual ionic entropy and an individual ionic entropy of hydration. 

Figure 10. Logarithm of self-diffusion coefficient vs. polymer-fraction function for 1200-EW perfluorosulfonate polymer, at 25°C. Na and Cs" lines without data points polystyrene sulfonate behavior. (Refs. 163 and 207 reprinted by permission of the publisher. The Electrochemical Society, Inc.)...

W.A. Boyle, R.F. Buchholz, J.A. Neal, J.L. McCarthy, Flow-injection analysis estimation of diffusion coefficients of paucidisperse and polydisperse polymers such as polystyrene sulfonates, J. Appl. Polymer Sci. 42 (1991) 1969. 

Paul et al. (25) observed that for polymer volume fractions less than 0.8, the functional dependence of the diffusion coefficients on the polymer volume fraction was, generally, in accordance with Equation 40. Muhr and Blanshard (26) provide additional supporting data on different polymers than those reported by Paul et al, Roucls and Ekerdt (27) measured the diffusion of cyclic hydrocarbons in benzene-swollen polystyrene beads their diffusion coefficients satisfy the general form of Equation 40. The effective dlffuslvltles of organic substrates in crossllnked polystyrene reported by Marconi and Ford (17) also follow trends predicted in Equation 40. In the absence of experimental data, it appears that Equation 40 provides a reasonable, and the simplest, means to estimate D for use in detailed modeling or in estimation methods such as Equation 38. Equation 40 was used by Dooley et al. (11) in their study of substrate diffusion and reaction in a macroreticular sulfonic acid resin which involved vapor phase reactants. 

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