Polyelectrolyte and non-polyelectrolyte polyacrylamide copolymer solutions: the role of salt on the intra- and intermolecular interactions

Poly(acrylamide-co-dihexylacrylamide) (PAHM-0) and poly(acrylamide-co-sodium acrylate-co-dihexylacrylamide) (PAHM-21) were studied through small-angle X-ray scattering (SAXS), light scattering (LS) and rheology. SAXS results highlighted the polyelectrolyte character of PAHM-21, with highly extended conformation in aqueous solution owing to charge repulsion, while the PAHM-0 has a coil conformation. LS measurements indicated that PAHM-0 makes intermolecular clusters in solution, in presence and absence of salt, even with a lower hydrophobic content than that described in the literature to the associative polyacrylamides. However, the rheological results showed that there is not an enhancement of the viscosity although hydrophobic association takes place. LS results for PAHM-21 suggest that this polymer makes intramolecular associations mainly in the presence of salts. Furthermore, the viscosity measurements show that its viscosity decreases due to screening of the charges by the addition of salts.

Bibliographic Details

Main Authors:	Maia,Ana M. S., Villetti,Marcos A., Borsali,Redouane, Balaban,Rosangela C.
Format:	Digital revista
Language:	English
Published:	Sociedade Brasileira de Química 2013
Online Access:	http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532013001100020
Tags:	Add Tag No Tags, Be the first to tag this record!