Abstract
Extrusion processing of filled polymers is commonly employed in various industries including compounding operations and in various processes involving composites. The analysis of extrusion processing of filled polymers is complicated by the ubiquitous viscoplasticity and wall slip of the filled polymers, the role played by entrainment of air in the processor, the continuously evolving microstructure and hence the rheological behavior of the filled polymer in the mixing volume of the extruder and the flow instabilities associated with the converging flows involving the filtration of the binder polymer. Furthermore, specialized techniques are necessary to quantitatively describe the dispersive and the distributive mixedness of the compound. The objectives of this study were to collect experimental data from the twin screw extrusion process using an instrumented and industrial-scale co-rotating extruder in conjunction with a well-characterized filled polymer, which exhibits viscoplasticity and wall slip and to compare the data with the results of numerical simulation using the Finite Element Method, under conditions of well-mixedness and proper removal of the air content of the suspension. The predictions compared favorably with the experimental temperature and pressure distributions obtained under different sets of operating conditions. The distributive degree of mixedness (spatial homogeneity) of the filled polymer upon exit from the die was also characterized employing a wide angle x-ray diffraction technique in spite of the amorphous nature of both the filler and the binder polymer, i.e., hollow glass spheres and poly(dimethyl siloxane) polymer.
Original language | English |
---|---|
Pages | 188-234 |
Number of pages | 47 |
State | Published - 1997 |
Event | Proceedings of the 1997 International Symposium on Polymer Blends, Alloys and Filled Systems, POLYBLENDS - Boucherville, Can Duration: 9 Oct 1997 → 10 Oct 1997 |
Conference
Conference | Proceedings of the 1997 International Symposium on Polymer Blends, Alloys and Filled Systems, POLYBLENDS |
---|---|
City | Boucherville, Can |
Period | 9/10/97 → 10/10/97 |