Polyion-counterion interaction behavior for sodium carboxymethylcellulose in methanol-water mixed solvent media

► Conductivities of sodium carboxymethylcellulose in methanol-water have been measured. ► A major fraction of the counterions remains free in methanol-water solutions. ► Counterion condensation is found to be spontaneous in these mixed solvents. ► Contraction of the polyion coils as temperature increases was observed. ► The monomer units become smaller at higher temperatures due to gradual desolvation.