Paper Number
PO9
Session
Poster Session
Title
Closed boundary shear rheology: An alternative to existing methods for high shear rate testing of filled polymer products
Presentation Date and Time
October 23, 2019 (Wednesday) 6:30
Track / Room
Poster Session / Ballroom C on 4th floor
Authors
- Latshaw, Alina (TA Instruments)
- Rauschmann, Thomas (TA Instruments)
- Reddy, Sandeep (TA Instruments)
Author and Affiliation Lines
Alina Latshaw1, Thomas Rauschmann2, and Sandeep Reddy2
1TA Instruments, New Castle, DE 19720; 2TA Instruments, Wetzlar, Germany
Speaker / Presenter
Latshaw, Alina
Text of Abstract
Fully characterizing the flow behavior of materials across a wide range of shear rates is imperative for the optimization of industrial processing operations. Specifically, elevated shear rate ranges are linked to processing behavior exhibited in pipe flow, molding processes, and extrusion, among other applications. For many polymeric systems, steady state viscosity measurements at high shear rates are difficult obtain on open boundary rheometers due to elasticity-induced sample fracture. Other measurement techniques such as conversion of complex viscosity through the Cox-Merz relation or commercial products such as capillary devices or the cone and partitioned plate may be used as alternatives, but still pose their own challenges. The Cox-Merz relation has proven to be an empirical relationship that is robust for homopolymers, but loses accuracy for complex blends, especially those with particulate fillers. Capillary rheometry requires a large volume of material for testing and additional corrections must be applied for accurate measurements. The cone and partitioned plate is a useful tool for performing steady shear measurements on open boundary rheometers, however it simply delays the onset of edge fracture. In this poster, we explore the measurement of steady shear viscosity at elevated shear rates using a steady state methodology in a closed boundary rheometer that overcomes many of the aforementioned challenges and provides a viable path to direct measurements for processing elastomer compounds.