And Why Do You Need It?
In this five part series, our applications engineer, Michele Scacchi, outlines why you need Large Amplitude Oscillatory Shear (LAOS) for rubber quality control, how it helps you measure your quality of mix, how to evaluate natural and synthetic rubber, fillers and reinforcement and how to analyze the results.
Optimizing Your Mixing Process Using FT-Rheology via LAOS
FT-Rheology via Large Amplitude Oscillatory Shear (LAOS) reveals more information about the filler-filler / filler-polymer interactions and provides a check at the end of the mixing process to determine if the full dispersion of the filler in the rubber matrix has been achieved.
Tracking the Progress of Filler Dispersion – Examples of LAOS Experiments
To validate the approach presented by Leblanc, we performed tests using several filled rubber compounds – including not only carbon black compounds but also silica rubber compounds. Experiments were run on Alpha Technologies’ Premier™ RPAs using FT-Rheology via LAOS.
Using LAOS to Quantify Long Chain Branching and to Predict Processability
The presence of long chain branching (LCB) in a polymer has a large impact on its viscoelastic properties and can affect significantly the processability of filled rubber compound: black incorporation time, die swell, extrusion behaviour. For instance, the incorporation of long chain branches has been used in EPDM and polyethylene (PE) to enhance shear thinning/flow behaviour and, in the case of PEs, to delay the onset of melt fracture toward higher shear rates.
Case Studies: Determination of Long Chain Branching in Polymer and Prediction of Processability
The LAOS technique is very sensitive to detect the long chain branching (LCB) in polymers and can be used for quality control in the thermoplastic and synthetic rubber production to check the polymer architecture and to predict the processability in their applications. Learn more in part four about case studies we have completed.
Run LAOS on the Premier RPA
Talk to our applications team about FT-Rheology via LAOS for mixing quality and long chain branching.