Polymer, Vol.46, No.12, 4052-4059, 2005
Relaxation behavior of hydrophobically modified polyelectrolyte solution under various deformations
The shear imposed oscillation technique was employed to probe the shear-induced structural changes of various model associative polymers in the shear-thinning and shear-thickening regimes. The shear-thickening behavior is related to the transformation from predominantly intra-molecular to inter-molecular associations. The shear-thinning behavior under moderate shear deformation is caused by the reorganization of the transient network structure. Under high shear deformation, the shear-thinning behavior is caused solely by the shear-induced effect that increases the chain-end exit rate, which reduces the mechanical active chains and lifetime of the hydrophobe in the micellar junctions. © 2005 Elsevier Ltd. All rights reserved.