title: Polyaromatic-anion behavior of different polyelectrolytes containing benzenecarboxylate units.
abstract: The polyaromatic-ion behavior of poly(sodium N-maleoyl-2-aminobenzoate-co-sodium acrylate) in a comonomer composition 1:2, poly(sodium N-maleoyl-4-aminobenzoate-co-sodium acrylate) in a comonomer composition 1:2, and poly(sodium N-maleoyl-4-aminobenzoate-co-N,N-dimethylacrylamide) in a comonomer composition 1:1 is studied. The copolymers undergo short-range aromatic-aromatic interactions with methylene blue and rhodamine B, as a consequence of which their UV-vis monomer band is shifted to lower energies. As a result of their polyaromatic-anion behavior, methylene blue is easily dispersed on the polymeric domains. Moreover, the pK(a) of rhodamine B is shifted from 3.2 to 4.5-5 in the presence of these copolymers. This behavior is also observed in the presence poly(sodium 4-styrenesulfonate), but not in the presence of poly(sodium vinyl sulfonate), which are taken as reference polymers. Compared with poly(sodium 4-styrenesulfonate), a lower resistance to the cleaving effect of added NaCl on the interaction with methylene blue is found. A different influence on the reduction of 2,3,5-triphenyl-2H-tetrazolium chloride with ascorbic acid was found for the different polyelectrolytes.
authors.affiliation: Instituto de Química, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile. imorenovilloslada@uach.cl
authors.forename: Ignacio
authors.initials: I
authors.lastname: Moreno-Villoslada
authors.forename: Mario E
authors.initials: ME
authors.lastname: Flores
authors.forename: Oscar G
authors.initials: OG
authors.lastname: Marambio
authors.forename: Guadalupe del C
authors.initials: Gdel C
authors.lastname: Pizarro
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nishide