ANALYSIS OF MICROMIXING IN TWIN SCREW EXTRUDERS USING REACTIVE POLYMER TRACERS

摘要

Micromixing in a co-rotating twin screw extruder was experimentally investigated during the mixing of two segregated polypropylene melt streams. The mixing limited reaction between two polymeric reactive tracers, which are terminally functionalized low molecular weight polymer chains, was used to determine the micromixing performance. The selected functional groups were succinic anhydride and a primary amine. Fourier Transform Infrared Spectrometry (FT-IR) was used to determine the anhydride conversion, which was related to the micromixing quality. Investigated factors included screw speed, total flow rate, and the viscosity ratio of the two melt streams. The last factor was controlled using a temperature difference between the melt streams. Statistical analysis of the experimental results showed the significance of the factor and interaction effects. Particular attention was given to the effect of screw speed on micromixing quality, which was found to be non-linear.