| Popis: |
The structure of a polymer solution depends on the type of polymer, on the polymer concentration, and on the shear rate existing in the fluid. Shearing polymer solutions can cause dramatic effects such as polymer degradation when a certain threshold shear stress is exceeded (Leopairat and Merrill, 1978). Under less severe conditions, experiments show that other critical or yield phenomena can occur in following polymer solutions where major perturbations of molecular shape and coil volume or pervaded volume can occur. Peterlin (1970) showed that molecular extension occurs in flow systems causing enormous increases in the radius of gyration of the dissolved polymer. |
