The rheological behaviour in the molten state of Acrylo nitril– Butadine –
Styrene (ABS) according to temperature, shearing stress and shearing rate
have been studied. Measurements were made with a capillary viscosimeter for
the static properties.
The correction of experimental data has been carried out.
Viscosity decreases with increasing shear stress or shear rate in the nonnewtonian
flow high polymer systems. However, the variation of activation
energy with temperature at fixed shear rate is always less then at fixed shear
stress.
A lubricant (Lithium-Sodium) of Syrian petroleum-based stocks and
thickener material depends in its preparation on Skinless chicken fat, was
manufactured at different ratios.
A study of physical - chemical properties of manufactured grease types w
as
carried out (compared with Syrian standard specification 791/2008) by using
standard methods which included: grease state, penetration degree, drop point,
free acidity (as oleic acid)% by weight, grease resistence to water, evaporating
at 90° C, and corrosion of copper plate. Where the results show that the best
type of grease is of 30% ratio.
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.
The recent synthesis of the new polymers has been profoundly affected by
the unique characteristics of Dimer Acid.
These polymers were made up following the condensation with
triethanolamine when was treated in melted phase.
We performed identifi
cation of the physical characteristics of the polymers
such as the molecular weight, in addition to the acid value and hydroxyl value.
Infrared spectroscopy have been used in identification of this polymer.
Also, the rheological behavior has been assessed thermally and shearing
stress by using capillary viscometer.
Our results revealed a reduction in the viscosity with increase of the
shearing stress as will as with rise in the temperature.
