Celsum Technologies is now supplying Dynisco's LCR7000 range of computer-controlled, benchtop capillary extrusion rheometers.
A capillary extrusion rheometer is a piston-driven, temperature-controlled machine that is used to extrude the test sample at a series of controlled speeds through a die of precisely known geometry, as well as measuring the pressure required to maintain extrusion at each speed.
From a knowledge of the instrument geometry, the scientific parameters of apparent shear rate, apparent shear stress and apparent viscosity can be calculated.
The data can be used to monitor changes in formulation, in the degree of mixing, in molecular weight, and to engineer extrusion dies, injection mould and other processing equipment.
Capillary extrusion rheometry can achieve process speeds comparable with those encountered on the factory floor.
The extrudate generated during the test may be subject to further analysis, for example, by DMA, DSC, TGA, tensile testing and other techniques.
The LCR7000 range has both single and twin bore instruments, with a maximum piston load of 10kN and a maximum barrel pressure of 1,400 bars, and there is a choice of piston-mounted load cells or barrel-mounted melt pressure transducers.
The supplied Lab Kars advanced rheology software runs from a PC, controls the instrument, gathers and stores the data, performs common rheological operations and has curve fitting routines to several mathematical models.
Optional equipment available includes a laser micrometer for measuring die swell online and a miniature granulator for sample preparation.
