Capillary rheometer: A practical rheological test instrument for both natural and synthetic rubbers

Comparisons related to rheological studies on various types of raw rubber and rubber compound by using the capillary rheometer are still very limited. in this work,rheological testing was performed on both natural rubbers (various standard malaysian rubber grades) and some market available common types of synthetic rubber (styrene butadiene rubber,ethylene propylene diene copolymer,nitrile rubber and isoprene rubber) in order to assess their processability and rheological behaviours. four different kinds of testing instrument were utilised for comparison purposes,i.e. a capillary rheometer,a mooney viscometer,a rubber process analyser and an internal mixer (in terms of breakdown index). these tests were based on three different types of rubber formulation,i.e. raw rubber,international standard organisation (iso) gum mix and iso black mix. based on the test results,capillary rheometer was identified as the best instrument for processability and rheological behaviours testing (for both natural and synthetic rubbers) due to its ability to perform measurements under the widest regime of true shear rate which had covered all the actual rubber processing conditions.