Scattering excluded-volume effects

It is well established that the excluded volume effect vanishes under a special condition of temperature or solvent, which is usually known as the Flory theta temperature or solvent. Thus, light scattering measurements performed on solutions under theta conditions can furnish direct knowledge of the unperturbed dimensions [see, for example, Outer, Carr and Zimm (207) Shultz (233) and Notley and Debye (207)]. Viscosity measurements, though less directly, can also furnish similar knowledge with the aid of the Flory-Fox equation (103,109), which may be written... 

Several papers compare the properties of sulfobetaine (meth)acrylic polymers. NMR spectra and solution properties of 23a and 23b [59,60] are correlated with data from the corresponding polycarbobetaines [26]. The photophysical and solution properties of pyrene-labeled 23c were studied in terms of fluorescence emission. Addition of surfactants induces the formation of mixed micelles in aqueous solution [61]. Excluded volume effects of the unlabeled polymer were measured by light scattering [62], its adsorption on silica was studied by adsorbance measurement and ellipsometry [62,63], and the electrostimulated shift of the precipitation temperature was followed at various electric held intensities [64]. Polysulfobetaines may accelerate interionic reactions, e.g., oxidation of ferrocyanide by persulfate [65]. The thermal and dielectric properties of polysulfobetaines 23d were investigated. The flexible lateral chain of the polymers decreased Tg, for which a linear relationship with the number of C atoms was shown [66,67]. 

Cannavacciuolo, L., Sommer, C., Redersen, J.S., and Schurtenberger, R, Size, flexibility, and scattering functions of semiflexible polyelectrolytes with excluded volume effects Monte Carlo simulations and neutron scattering experiments, Phys. Rev. E, 62, 5409, 2000. 

FIG. 14 Dependence of the second virial coefficient on added-salt concentration. NaPSS in NaCl solutions. Results by light scattering from Ref. 41 ( ), Ref. 30 (A) and by osmometry from Ref. 41 (o). The dashed line shows calculation of the second virial coefficient by incorporating electrostatic excluded volume effects after Ref. 30. 

Dimensions Of Rings And Chains In DUute Solution By Small Angle Neutron Scattering. Theoretical predictions of the z-average mean-square radii of gyration (z,c=o) for flexible linear and cyclic polymers with the same number of skeletal bonds in dilute solution at the 6-point, which are unperturbed by excluded volume effects, predict a ratio of 2,c=o / = 2.0 [42] [43] [44] (where 1 refers to... 

---