Some Effects of Storage and Shear History on the Friction Reducing Properties of Dilute Polymer Solutions

Download or read book Some Effects of Storage and Shear History on the Friction Reducing Properties of Dilute Polymer Solutions written by A. T. Ellis and published by . This book was released on 1970 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The drag reducing properties of two dilute polymer solutions were studied using a simple turbulent pipe flow apparatus under various conditions of storage and mechanical degradation. Aqueous solutions of Polyox WSR-301 (polyethylene oxide) and Separan AP-30 (polyacrylamide) were prepared at 500 PPMW and then diluted into weak concentrations for storage and testing on a day by day basis. Data which display the friction reducing effectiveness as a function of aging and repeated shear degradation are presented for both polymers. At concentrations of 10, 25, 50 and 100 PPMW, aged samples showed the same 'peak' effectiveness as freshly prepared ones. However, the aging process reduced all the ability to resist mechanical degradation. Anomalies were found in which solutions tend to partially recover from shear degradation under certain conditions, and in other cases tend to improve their friction reducing efficiency after continuous shearing. Experimental results suggest that entanglement or aggregation of polymer molecules could be one of the important mechanisms involved in friction reduction. (Author).