Connecting the final properties of PDMS with rheological data of the base components
Sprache des Vortragstitels:
Annual European Rheology Conference 2014
Sprache des Tagungstitel:
Depending on the desired features the wide variety of polydimethylsiloxanes (PDMS) types with different properties (viscosity, hardness, elongation modulus) and applications makes it necessary to select the used type properly. Additionally, knowledge about the crosslinking behavior of PDMS is very important for scientists dealing with it or its composites.
During this work different types of PDMS were investigated to find a fully crosslinked PDMS with the desired properties. Therefore the base components (PDMS and crosslinker) were characterized very well and the crosslinking behavior was examined with Rheometry.
Several different rheological measurements were carried out with an ANTON PAAR UDS 200 Rheometer. The base components were examined via frequency sweeps whereas there are different ways of following the curing via Rheometry, namely strain-controlled time resolved frequency sweeps (=time-resolved mechanical spectroscopy = TRMS) and stress-controlled time tests. The TRMS measurements were done at a frequency range between 0.1 and 100 rads-1 (both at 25°C), the stress-controlled tests with constant stress = 75 Pa and constant frequency = 1 Hz. We found a reasonable accordance between these two ways. Through the rheological data we can predict the final properties of the cured PDMS and additionally gain parameters after which we can select the appropriate PDMS for our application.