Thermo Scientific HAAKE RotoVisco 1 Instruction Manual page 152

Terms of Rheological Measurements
Oscillating Movement:
OSC: Oscillation
Measuring mode for the non-destructive determination of elastic and
viscous material properties.
Here e.g. the influence of the frequency by forced oscillating stress on the
storage and loss modules (G' and G") can be investigated.
The measuring data gained in the linear visco-elastic range allow conclu-
sions on other physical quantities (e.g. molecular quantities for polymers)
(HAAKE RheoStress)
Flow Properties regarding Viscosity Behaviors
Newtonian: Property of substances where the viscosity will not change under shear
rate and shear stress.
(HAAKE Falling Ball Viscometer, System Höppler)
Pseudoplastic: Property of substances where the viscosity will decrease under shear
rate and shear stress.
(Most common material behavior)
Dilatant: Property of substances where the viscosity will increase under shear rate
and shear stress.
Thixotropic: Non-Newtonian substances where the viscosity decreases under shear
(structure break-down). The substances will eventually regain their vis-
cosity after the shearing has stopped.
Rheopectic: Non-Newtonian substances where the viscosity increases under shear
(structure build-up). The substances will eventually regain their viscosity
after the shearing has stopped.
(Rare phenomenon)
Plastic: Property of non-Newtonian substances which only start flowing after being
subject to a certain force (shear stress), i.e. after a certain yield point. The
yield point strongly depends on external parameters like temperature and
change rate of the acting force. Therefore, a "practical" yield point is
determined taking in account the environmental conditions specific for the
application.
(Measuring modes: CD, CS)
(HAAKE ViscoTester 550 / RotoVisco1 / RheoStress)
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