Dynamic light scattering, ionomer solution

Various techniques have been used to study the solution properties of ionomers. These include viscosity (4, 1 ), static and dynamic light scattering (12.13.15-18), small-angle neutron scattering (11.14). and spectroscopy (10). Here, we use (static and... 

Stieber, F. and Eicke, H.-F. (1996) Solution of telechelic ionomers in a water/AOT/oU (w/o) microemulsion A static and dynamic light scattering study. Colloid Polym. Sci., 274, 826-835. 

Here we describe dynamic light scattering results on ionomers in a salt-free, nonaqueous, polar solvent such a solution has a stronger scattering power and is easier to handle than polyelectrolytes in water, as already discussed in the Static Scattering section. 

Dynamic light scattering experiments were conducted for sulfonated PS ionomers in DMF [87]. CONTIN analysis of the decay rate generally indicates the existence of two decay modes. Both modes have a q2 dependence and therefore are diffusive processes. This is similar to that observed for salt-free polyelectrolytes in aqueous solution [76-79],... 

Nomula S, Cooper SL. Structural studies of polyurethane ionomer solutions. 1. Dynamic light scattering. Macromolecules 1997 30 1355—1362. 

Dynamic light scattering has also been used to study ionomer aggregates in solution. It was shown that hydrodynamic radius increases with increasing ion content and ionomer concentration (up to a certain point, above which the hydrodynamic radius becomes almost constant in the case of the THF solution [8]). While Lantman et al. only obtained hydrodynamic radii from scattering data at an angle of 90°, Pedley et al. used the cumulant method to obtain information on the distribution of aggregates and found that the quality factor. 

So far most studies of aggregation behavior have been conducted with low polarity solvents such as THF [4,9,15]. Recently there have been a few reports with nonpolar solvents such as xylene [16-18]. While these systems require low ion contents to form a solution, the ionomer electrical environment is more similar to that found in the solid state (i.e. low dielectric constant). In this work we use static and dynamic light scattering techniques to examine the aggregation behavior of sulfonated polystyrene ionomers in a nonpolar solvent, toluene. 

Bodycomb J, Hara M. Light scattering study of ionomers in solutions. 5. CONTIN analysis of dynamic scattering data from sulfonated polystyrene ionomer in a polar solvent (dimethylformamide). Macromolecules 1995 28 8190-8196. 

These results confirm the observation that polyelectrolyte aqueous solutions show two separate decay modes in the autocorrelation function and support our contention that ionic polymer systems generally behave similarly in polar solvents [23], To support this, it may be added that similar dynamic scattering behavior was recently reported for another type of ionomer, polyurethane ionomer, dissolved in a polar solvent, dimethylacetamide (e = 38) [92], Finally, it should be stressed that the explanation given above for light scattering (both static and dynamic) behavior of salt-free polyelectrolytes is based on the major role of intermolecular electrostatic interactions in causing characteristic behavior. No intramolecular interactions are explicitly included to explain the behavior. This is in accord with our contention that much of the polyelectrolyte behavior, especially structure-related aspects, is determined by intermolecular interactions [23]. 

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