Handbook of Solvents - George Wypych - ChemTech - Ventech!

686 George Wypych
Viscosity, Poise
10 9
10 8
10 7
10 6
10 5
10 4
1000
100
1000 10 4
10 5
10 6
Molecular weight, Daltons
Figure 12.1.3. Viscosity of 40% polystyrene in
di-2-ethyl hexyl phthalate. [Data from GDJPhillies,
Macromolecules, 28, No.24, 8198-208 (1995).]
Viscosity, mPa s
1.2
1.1
1
0.9
0.8
0.7
DXN
DCE
10 7
0.6
0.5 THF
CHCl
3
DCM
TOL
0.4
0 10 20 30 40 50
PMMA concentration, %
CCl 4
Figure 12.1.5. Viscosity of PMMA solutions in different
solvents vs. PMMA concentration. Basic solvents:
tetrahydrofuran, THF, and dioxane, DXN; neutral: toluene,
TOL and CCl 4; acidic: 1,2-dichloroethane, DCE,
CHCl 3, and dichloromethane, DCM. [Adapted, by permission,
from M L Abel, M M Chehimi, Synthetic
Metals, 66, No.3, 225-33 (1994).]
Shear rate, s -1
0
0 5 10 15 20
the accuracy of measurements by application
of nonlinear liquid standards. 4 Figure
12.1.2 shows the effect of polymer concentration on the viscosity of a solution of
polyphenylene in N-methyl pyrilidinone. 5 Two regimes are clearly visible. The regimes are
divided by a critical concentration above which viscosity increases more rapidly due to the
interaction of chains leading to aggregate formation. These two sets of data show that there
500
400
300
200
100
Molecular weight x 10 -6
Figure 12.1.4. Shear rate of polystyrene in DOP vs. molecular
weight. [Data from M Ponitsch, T Hollfelder,
J Springer, Polym. Bull., 40, No.2-3, 345-52 (1998).]
log η rel
1.4
1.2
1
0.8
0.6
0.4
0.2
associated
unassociated
0
0 0.5 1 1.5 2 2.5 3
Concentration, g dl -1
Figure 12.1.6. Relative viscosity of block copolymers
with and and without segments capable of forming
complexes vs. concentration. [Data from ICDeWitte,
B G Bogdanov, E J Goethals, Macromol. Symp., 118,
237-46 (1997).]