- Identification: A2060702 - Grant Agency of the Academy of Sciences of the Czech Republic
- Duration: 1997 - 2001
- Principal investigator: Petr Filip CSc.
- Co-investigator: Doc. Ing. Petr Sáha CSc. (Faculty of Technology, Technical University)
Measurements using various compositions of polymer blends (LDPE, HDPE, PP, polybutadiene) will be carried out in the models of extrnsion dies. The onset of flow instability (stick-slip regime) and its limits will be analysed and optimized taking into account rheological and macromolecular behaviour of processed materials together with the geometrical and kinematical parameters characterizing the corresponding experimental arrangements. For a description of rheological properties Williamson model will be generalized and the influence of molecular characteristics on model parameters will be estimated; emphasis will be given to the regions of nonmonotonous dependence of shear stress on shear rate. Analysis of Couette-Poiseuille flow will be carried out from the viewpoint of the rheological control of polymer flow in extrusion dies. Attention will be paid to the relation flow rate vs. driving forces.
