%0 Journal Article
%T ELECTRICAL CONDUCTIVITY OF HYDROPHOBICALLY MODIFIED POLYELECTROLYTES IN METHANOL/WATER SOLUTION
%A BARRAZA
%A RAUL G.
%A OLEA
%A ANDRES F.
%A FUENTES
%A IRMA
%A MARTINEZ
%A FRANCISCO
%J Journal of the Chilean Chemical Society
%D 2003
%I Scientific Electronic Library Online
%R 10.4067/S0717-97072003000100012
%X measurements of the electrical equivalent conductivity of potassium salts of poly(maleic acid-co-1-olefins), pa-nk2 with n = 12, 18 has been carried out in methanol-water mixtures in the whole range of composition. the relative interaction parameter f*, was determined as a function of the mole fraction of methanol. the values of f* do not follow the same tendency of the limiting equivalent conductivity. this unusual behavior was rationalized in terms of a methanol-induced conformational transition that takes the polymer chain from a compact to an expanded structure. as a consequence of this transition the average charge distance in the polyion increases with increasing mole fraction of methanol. this brings about a decrease of the linear charge density parameter, and therefore an increase of the fraction of polymer charges dissociated from their counterions. the existence of the conformational transition of the pa-nk2 copolymers was confirmed through fluorescence probing experiments
%K polyelectrolytes
%K electrical conductivity
%K counterion condensation
%K conformational transition.
%U http://www.scielo.cl/scielo.php?script=sci_abstract&pid=S0717-97072003000100012&lng=en&nrm=iso&tlng=en