Flow properties of polystyrene solutions under high shear rates

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Abstract
This manuscript reports on the development of a high‐shear Couette viscometer. The main design considerations for a high‐shear concentric cylinder viscometer are reviewed and discussed. In principle, the instrument is identical to those used by other investigators. However, some modifications were found necessary. Attention is drawn to the importance of the concentricity problem. The instrument was first tested and calibrated using Newtonian standard oils. Then non‐Newtonian runs were performed using narrow polystyrene standards of molecular weights 97,200, 411,000, and 860,000. Solutions of the polymer in n‐butylbenzene ranged in concentration from 0.08 g/cc up to 0.5 g/cc. The shear rates applied ranged from 103 sec−1 up to 105 sec−1. The results obtained were compared to the molecular entanglement theory, and excellent agreement was observed.
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