This course will be offered during the third AND fourth quartile.|
After the course the student is able to...
- Apply spring-dashpot models to represent linear viscoelastic material behavior in both static and dynamic loading cases.
- Give an in depth explanation of (the background behind) physical models related to linear viscoelastic behavior, such as the Boltzmann principle and time-temperature superposition using both Arrhenius and WLF relations.
- Name and explain the several limitations of the linear viscoelastic theory, such as the consequences of physical ageing.
- Give a general description of 3D modelling of viscoelastic behavior.
- Describe basic rheometric techniques and the related testing geometries.
- Apply the above mentioned theories on the melt behavior of polymers to model the behavior of polymer melts during extrusion and other processing techniques .
- Describe the influence of processing conditions, such as temperature, flow rate and cooling rate, on the crystallization behavior of a polymer melt.
- Write a review based on scientific literature and communicate findings on a specific rheological topic
- Perform numerical or experimental research in the field of rheology.
Knowledge on the visco-elastic behavior of polymer melts is not only of crucial importance for conventional processing techniques such as extrusion and injection molding, but also for novel processing technologies for the production of thermoplastic composite products. This course starts off with a description of the basic models for describing the properties of the visco-elastic behavior of polymer melts (relaxation, creep, dynamic behavior, linear visco-elastic theory and time-time temperature superposition), power law, rubber elasticity and reptation). With the use of this knowledge, the link between experiments to characterize the rheological behavior (rheometry), the material behavior during processing (e.g. crystallization), and the final mechanical properties of the polymer will be elaborated.|
To finish the course the students will independently (or in small groups) carry out a lab practical. Next, a numerical or experimental research is performed on a rheological topic. The findings together with a literature review on the topic have to be described in a report and defended during the oral exam.