The study was carried out on the lithium Lubricants in the molten state
under the effect of tempearture, shear stress (τ), and shear rate (γ) by using
capillary viscometer, the corrections have been done to expermintal data. It
was found from the
obtained results that, real viscosity ηc decreased with
increasing real shear rate (γc). Also it was found that the lithium Lubricants is a
pseudoplastic material (n<1).
The aim of this work is to study the flow behavior of white Vaseline "which
is used in pharmaceutical industry and Cosmetics" in statical state.
The study was carried out on the white vaseline in the molten state under
the effect of temperture, sh
ear stress (τ), and shear rate (γ) by using capillary
viscometer, then the corrections have been done to expermintal data. It was
found from the obtained results that, real viscosity decreased with increasing
real shear rate (γc). Also it was found that the vaseline is a pseudoplastic
material (n<1).
For determining viscous activation energy at constant shear rtae (Eγ) and
shear stress (Eτ), the relationship between real viscosity (ηc) and (1/T) was
studied. It was found that the viscous activation energy decreased with
increasing the shear rate and shear stress, where the value of viscous activation
energy reflectes the temperature–sensitivity of real viscosity.
Elastic properties for vaseline were studied by determining the die swell
ratio (B) (Barus effet), and it was found that (B) increased with increasing
shear stress, but it decreased with increasing L/R ratio, while the temperature
do not have any effect on (B). The time residence (tr) of vaseline in the die was
deterimined and studied the relationship between (B) and (tr).
Note: vaseline does not carry any kind of bacteria, because it is unsuitable
medium for their growth.
