chemia - Studia

THE RHEOLOGICAL STUDY OF SOME SOLUTIONS BASED ON SURFACE-ACTIVE AGENTS (II)
Ta
Re
2 2
( − )
2⋅π
⋅n⋅
r o
r
=
i
η
2
o
a
2
o
2
i
⋅ ρ
(1)
2 ⋅π
⋅ n ⋅ r
γ& =
(2)
r − r
RESULTS AND DISCUSSION
1. The temperature influence
The influence of temperature on the rheological behavior was
determined for samples PA 2-8 , PA 2.5-8 , and the series PC 1 -PC 5 . In Figure 1,
dependence τ = f (γ&
) is shown, at different temperature values, for PA 2.5-8 .
2.5%VAD + 8%VB
25
20
Shear stress, Pa
15
10
5
0
0 100 200 300 400 500 600 700 800
Shear rate, s -1
t=25C t=32C t=39.5C
Figure 1. Dependence = f &)
for PA 2.5-8 at different temperatures
τ
(γ
The rheological equations for samples PA 2-8 and PA 2.5-8 are presented
in Tables 3 and 4.
Table 3. Rheological equations for PA 2-8 sample at various temperatures
Temperature, ºC
Equation
= 13.9
+ 0.78⋅
& γ
32 0. 263
39.5 0. 553
τ = 12.8
+ 0.47 ⋅ & γ
τ
Table 4. Rheological equations for PA 2.5-8 sample at various temperatures
Temperature, ºC
Equation
= 10.8
+ 0.13⋅
& γ
25 0. 575
32 0. 363
τ
τ = 10.4
+ 0.86 ⋅ & γ
39.5 0. 435
τ = 1.5
⋅ & γ
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