Effects of the Surface Tension upon the Viscosity Behavior of Dilute PEO Solutions

The viscosity behavior of poly(ethylene oxide)(PEO) with different molecular weights in the water and benzene was determined respectively. Itwas noted thatthe reduced viscosityof PEO in thewater deviated negatively from the linear relationship at lower concentrations in the reduced viscosity versus concentration plot. On the other hand, the reduced viscosity of PEO in benzene increased linearlywith concentration even at lower concentrations. The surface tension measurements indicated that PEO could reduce the surface tension ofwater considerably but had no effect on the surface tension of benzene. The influence of the surface tension upon the viscosity behavior of polymer solutionwas notable, especiallywhen the surface tension between the polymer solution and the pure solvent was significant. By measuring the surface tension ofwater and aqueous PEOsolution, togetherwith the geometric parameterof the viscometer, the influence of the surface tension upon the measurement of the flowing time could be studied quantitatively. The calculations were consistentwith experimental results approximately. Ift0*was employed to determine the viscosity of polymer solution, the influence of the surface tension upon the viscosity behavior of polymer solution could be counteracted completely and the reduced viscosity of PEO in water increased linearlywith concentration just the same as PEO in benzene.