Transport properties of some cationic polysaccharides

Hydrodynamic properties of some cationic amphiphilic polysaccharides in dilute and semi-dilute aqueous solutions

“…This problem can be solved either by addition of low-molar-mass electrolyte or by means of semi-empirical equa- Fuoss and Strauss (1948), Yang (2004), Rushing and Hester (2004), or Wolf (Eckelt, Knopf, & Wolf, 2008). Fedors' equation (Fedors, 1979) modified by Rao (Rao, 1993) and verified for neutral polymer, has been successfully extended to some polyelectrolytes in both water (Ghimici & Popescu, 1998;Ghimici & Nichifor, 2006) and water/organic solvent mixtures (Dragan & Ghimici, 2001;Ghimici & Avram, 2003;Ghimici & Nichifor, 2006). In the case of amphiphilic polymers, the meaning of the intrinsic viscosity can sometimes be doubtful since macromolecules can form aggregate (inter-or/and intramolecular), as we have already shown for these polymers using fluorescence techniques based on fluorescence probe or fluorescently labeled polymers (Nichifor, Lopes, et al, 2004).…”

Characterization of highly substituted, cationic amphiphilic starch derivatives: Dynamic surface tension and intrinsic viscosity

“…Semi‐empirical equations could describe the viscosity variation with concentration only for polymers with low degree of substitution. This equation, which was modified by Rao and verified for neutral polymer, has been successfully extended to some PELs in aqueous solution . In the case of amphiphilic polymers, the meaning of the intrinsic viscosity can sometimes be doubtful since macromolecules can form inter‐ or/and intramolecular aggregates .…”

Novel biodegradable flocculanting agents based on pullulan

“…The applicability of the Rao equation to describe the viscosity of the polymer solution was also found in the case of other polyelectrolytes [35][36][37].…”