| 摘要 |
The invention relates to the continuous or discontinuous measurement of viscosity and its distribution, and of the melt flow index (MFI) or volumetric flow index (MVI) of non-Newtonian, in particular pseudoplastic, viscously similar and viscously dissimilar liquids, in particular polymer melts. The liquid is fed by means of a volumetric, controllable metering pump through a first capillary section or a first capillary and at least one further capillary section or a further capillary connected in series downstream of the first capillary section. A flow coefficient, in particular the viscosity or a measure of the viscosity distribution, is determined each time from the pressure drop over each capillary for a known measured volume flow. To achieve the capability of correlating viscosity and flow index and the clear assignment with respect to mean molecular weights and their distributions and changes, provision is made for the volumetric flow passed through the capillary sections to be controlled in such a way that the pressure drop over at least one capillary section is kept constant and for the volumetric flow delivered by the pump to be determined. <IMAGE> |
