- Identification: 26051 - Grant Agency of the Academy of Sciences of the Czech Republic
- Duration: 1992 - 1994
- Principal investigator: Ing. Pavel Říha CSc.
The volume changes of polymer melts under the flow at the constant temperature and pressure result from the increased motion of macromolecules and the subsequent decrease of their packing in comparison with the packing under equilibrium at rest. The volume changes had been so far studied only experimentally and described from the phenomenological point of view. The aim of the project is to explain and describe the volume changes on basis of the inner mechanism inducing the changes, namely, on basis of the motion of individual molecules of melted polymers. The description will follow the published molecular theories of polymer melts and will modify them in a way that the distribution function of the molecule configuration will be influenced by possible volume changes. The theoretical description will be compared with the results of the corresponding experiments published already in the literature. Supplementary data will be provided also by the Department of Polymeric Materials of Chalmers University in Gothenburg. Within the framework of mutual cooperation were already published preliminary results.
