Solvation of N-chloranil and N-xylylene tagged cationic polyelectrolytes: Viscosity measurements in dimethylformamide and dimethyl sulphoxide

Abstract

Viscosity studies of four new types of cationic polyelectrolytes (mol. wt. 1167 to 6432), where quaternary nitrogens in the molecular chain are tagged with chloranil and xylylene moieties and are interspersed with ethylene, phenothiazine and bipyridyl (viologen) linkages, have been studied in the two dipolar aprotic solvents viz., dimethylformamide and dimethylsulphoxide at 298 &plusmn; 5 K. All results have been treated on the basis of Fuoss equation,&eta;_sp/C=A/(1 +<em>B</em><em>&Ouml;</em><em>C}, </em>where (&eta;_sp /C}_c-o led to an estimation of intrinsic viscosity ([&eta;]).The [&eta;] values signify not only the measure of molecular size of the polymer but also connote frictional resistances toward solution flow by the specific conformation of individual molecule in infinitely dilute solution. The increase in &eta;_sp /C with dilution might not be due to chain expansion in all the cases. Thus, intrinsic viscosities in conjunction with other derived parameters, such as characteristic ratios (C_&yen;),maximum cross dimension (S), root mean square end-to-end distances (&lt;R²_g&gt; <em>1/2) </em>and plane projection distances (P) at all temperatures have been invoked to propose the hydrodynamic models of polycations in the medium of intermediate permittivity.