Title
Experimental and simulated measurement of in-line rheological behavior of cellulose diacetate in extrusion processing
Authors
YAJUN DING and SANJIU YING

Published Volume 50 Issue 3-4 March-April
Keywords CDA, in-line rheological behavior, slit rheometer, numerical simulation

Abstract
The in-line rheological properties of cellulose diacetate (CDA) in extrusion processing have been measured by a slit rheometer and simulated by Polyflow software under different process conditions. The Power model was applied for numerical simulation, and the results indicated that Polyflow is feasible to simulate the flow of the CDA solution. The distributions of velocity, pressure, shear rate and shear viscosity in the slit were simulated using Polyflow. Both the increasing temperature and solvent content improved the fluidity of the CDA solution, which reduced the shear viscosity. An increasing screw speed was helpful to improve the output of production, but it deteriorated the quality according to the numerical simulation. Because of the evaporation of solvents, the values of shear viscosity calculated by experiment were higher than those obtained from Polyflow. The experiment and numerical simulation of the in-line rheological behavior of the CDA solution have guiding significance for optimizing the process conditions of CDA.