The
SVT 20 is used for the software controlled and video
supported measurement of:
Static
and time dependent interfacial tension between two not
completely miscible liquids,
Two
and three-dimensional extensional relaxation of
viscoelastic liquids and liquids droplets encapsulated or enclosed in membranes.
Yield
point of e.g. liquid crystalline materials.
Thermal
expansion coefficients of liquids
Spinning drop method
All
measurements are performed according to the Spinning Drop
and Oscillating Drop Method.
The
32-bit Windows 2000/XP software
developed for the SVT 20 offers:
Time dependent control of rotational speed as well as
the adjustment of the capillary position in height and tilt
Recording and evaluation of video sequences for the
measurement of fast relaxational vibrations of drops
Calculation of interfacial tensions from the shape of
rotating drops (spinning drops) according to the Young-Laplace
equation as well as according to the Vonnegut
approximation for sufficiently extended droplets
Calculation of relaxational modules, yield points and
other rheological parameters
Software correction of distortions of the droplet image
by the glass capillary
An extended liquid data base with more than 140
parameter entries
Technical
data
Measuring
range:
Interfacial tension:
1¡P10-6
¡K 2¡P103mN/m
Speed
range:
0
... 15,000 rpm, Accuracy: ¡Ó 0,5 rpm
Speed
regulation: max.
¡Ó
2.000 rpm/s
Oscillations
frequency: 0,01 ... 200 Hz with minimum 3000 rpm
