TIME EFFECTS IN VISCOSITY OF POLYMER SOLUTIONS.
Final rept. 1 Mar 67-28 Feb 70,
RESEARCH TRIANGLE INST DURHAM N C CAMILLE DREYFUS LAB
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The time dependence of rheological and rheooptical properties of dilute polymer solutions was studied on solutions of high molecular weight polymers in extremely viscous solvents as chlorinated diphenyl and oligobutenes. The choice of solvent and solute was based on the model of aggregate formation in laminar flow which predicts the dimer formation by two solute molecule collision as the first step in aggregation which shows up in the time dependence of viscosity. As a by-product of this investigation one could obtain valuable data on streaming birefringence of polymer solutions at extremely high values of the dimensionless gradient parameter where, according to the theory, the first indications of saturation are expected to be caused by finite macromolecule length. Beyond that the study of the expansion of macromolecules in laminar flow with transverse and longitudinal gradient lead to a simple molecular model of drag reduction by high polymer additives of high molecular weight. Author
- Physical Chemistry