INDUSTRIAL AND ENGINEERING CHEMISTRY
1820
=
Vol. 47, No. 9
shearing stress, P R / 2 L dynes/sq. cm.
= Newtonian or zero shear viscosity a t temperature 2'
/::L
apparent viscosity a t temperature T , rU = Newtonian or zero shear viscosity at temperature To = real part of complex dynamic viscosity a t temperature 7' = real part of complex dynamic viscosity at temperaturr
=
'x.
-
= = = =
POLYMER
o
5 and IO T ~ 0 2
6
C u Phtholocyonine
+
0---2 S I 0 2
e
t I
'
2 S I O Z Heated
%.
e
'n
I
I
.
1
1
.
/
105
Figure 9.
I
1
REDUCED
RATE
OF
I
106
SHEAR,
_I
nTSw s e e .
=
10'
Filled dimethylpolysiloxane, 427,000 molecular weight
NOMENCLATURE
D K L P Q R
= slope A log D / A log
shearing stress a t capillary wall
'0
I n summary, the reduced variable treatment as shown by Ferry and DeWitt serves t o define a single curve for the reduced viscosity as a function of the reduced rate of shear for a given dimethylpolysiloxane over a wide range of temperature. Moreover, this technique also serves t o separate the effects of fillers into active and inert classifications.
c
To
circulap frequency, 2~ times frequency Newtonian or zero shear fluidity apparent fluidity, D,/T,, energy of activation as temperature coefficient for relaxation times 3 c
T
nominal shearing rate 4 & / ~R3(sec.-') proportionality constant in power lam length of capillary, cm. pressure in capillary, dynes/sq. cm. volume of extruded, cc./sec. = radius of capillary, cm. = reduction factor for relaxation times a t temperature 2' UT E,,,,, = energy of activation for viscous flow (from zero shear viscosities) = = = = =
Y
LITERATURE CITED
Barry, A . J., .I.Appl. Phys., 17, 1020 (1946). Currie, C. C., and Smith, B. F., IND.ENG.CHEM.,4 2 ,
2467
(1950).
DeWaele, A., Kolloid Z.,36, 332 (1925). DeWitt, T. W., SOC.Rheology, New York, Oct. 29-31, 1953. DeWitt, T. W., Padden, F., and Markorits, H., Phus. Rei., 9 1 , 2 1 7 (1953).
Einstein, A., Ann. phys., (4) 19, 289 (1906). Ferry, J. D., J . Am. Ckem. Soc., 72, 3746 (1950). Guth, E., and Gold, C. O., Phys. Rev., 5 3 , 3 2 2 (1938). Harper, R. C., Rlarkovitz, H., and DeU'itt, T. W., .T. Polptr7 Sci., 8, 435 (1952).
Iiutting, P. J., J . FranklinInst., 1 9 1 , 6 7 9 (1921). Ostwald, W., 2. physik. Chem., 111, 62 (1924). Rabbinowitsch, B., Ibid., 145A, 1 (1929). Scott Blair, G. W., Nature, 1 4 6 , 8 4 0 (1940). Smallwood, H. AI., J.A p p l . Phys., 8 , 5 0 5 (1937). Spencer, R.S., and Dillon, R. E., J . Colloid Sci., 3, 163 (1948). Warrick, E. L., and Lauterbur, P. C., IND. ENG.CHEM.,4 7 , 486 (1955).
Zapp, R., and Guth, E., Ibid.,4 3 , 4 3 0
(1951).
RECEIVED for review November 8, 1954.
A C C ~ P T KMarch D 14, 1955. Contribution from the multiple fellowship sustained a t Mellon Institiite, Pittsburgh, Pa., by the Corning Glass Works and Dow Corning Corp.
Inhibition of Rubber Oxidation by Carbon Black J
I
