A New Model of Polymers in Flow

Abstract

Recent experimental evidence has shown that polymer chains compress in flow at semi-dilute concentrations. It has been assumed in all models of polymer flow behaviour that the chains extend in flow. A new model of polymers in flow in semi-dilute solution is presented where the chains compress. The chains are modeled as simple Hookean dumbbells exposed to compressive hydrodynamic forces. Equating the hydrodynamic and elastic forces predicts chain compression with shear rate. The model predicts both the power law behaviour observed for polymer shear thinning and the measured decrease in radius with shear rate with reasonable accuracy.

Broadening of polymer chromatographic signals: Analysis, quantification and correction through effective diffusion coefficients

“…Additional effects are found in the description of polymeric solutions. Several studies were carried out in order to describe effects of flow rate on radius of gyration for flexible polymers and consequently on the hydrodynamic radius, the GPC elution volume and finally on average molecular weight and polydispersity index [7][8][9].…”