Capillary Rheology with Bagley Correction (1 Temperature)
Capillary rheology measurements contain errors from additional entrance and exit losses across the die. This test corrects for these errors by taking data using an additional 5 L/D, 1 mm diameter die and extrapolating to a zero L/D. (Alternatively, a zero L/D die can be used.) The sample, dried if needed, is loaded into a preheated test barrel of a capillary rheometer. A range of flow rates is used, attempting to cover a shear rate range of 10-10,000 /s. Pressure drop across the die is measured for each flow rate, and viscosity-shear rate data are calculated. Weissenberg-Rabinowitsch corrections are performed. The extrapolated end pressure loss is subtracted from the data to obtain Bagley (or entrance pressure) corrected data. Further analysis can be applied to quantify extensional flow effects.
A zero L/D orifice die can be used for Bagley corrections. Pressure can also be made using a load cell instead of a pressure transducer.
- ASTM D3835
- ISO 11443
Shear Viscosity v. Shear Rate. This data appears in Matereality as Capillary Viscosity.
Number of times this test is repeated: 1
0.5 kg of pellets [details]
These tests are required when an accurate measure of shear viscosity is desired.