ACKNOWLEDGMENT
I thank E. Whalley f o r helpful discussions, and R. J. Farland, National Oceanographic Instrumentation Cent e r , Washington, D. C., f o r sending me the observations of Carnvale and coworkers ( 2 ) . LITERATURE CITED
Barlow, A. J., Yazgan, E., Brit. J . Appl. Phys. 17, 807 (1966). Carnvale, A., Bowen, P., Basileo, M., Sprenke, J., J. Acoust. SOC.Am. 44, 1098 (1968). Diaz-Pena, M., McGlashan, M. L., Trans. Faraday SOC.55, 2018 (1959). Kell, G. S., J. CHEM.ENG.DATA12, 66 (1967).
Kell, G. S., Whalley, E., Phil. Trans. Roy. SOC.A 258, 565 (1965). Macdonald, J. R., Rev. Mod. Phys. 41, 316 (1969). McSkimin, H. J., "Physical Acoustics," W. P. Mason, ed., Vol. l A , p. 271, Academic Press, New York, 1964. McSkimin, H. J., J . Acoust. SOC.Am. 37, 325 (1965). Millero, F. J., Curry, R. W., Drost-Hansen, W., J. CHEM.ENG.DATA14,422 (1969). Slie, W. M., Donfor, A. R., Litovitz, T. A,, J . Chem. Phys. 44, 3712 (1966) Stimson, H. F., Am. J . Phys. 23, 614 (1955). Stimson, H. F., J . Res. Natl. Bur. Std. 65A, 139 (1961). I
RECEIVEDfor review July 7, 1969. Accepted September 22, 1969. NRC No. 11169.
Thermal Conductivity and Viscosity of Biphenyl and the Terphenyls W. H. HEDLEY,' M. V. MILNES,2 and W. H. YANK0 Monsanto Research Corp., Dayton, Ohio The thermal conductivities and viscosities of liquid biphenyl and the three terphenylt were measured over a range of temperatures using the hot-wire and capillary viscometer methods. These properties were also calculated as a function of temperature in the vapor phase to provide data for calculation of the performance of these compounds in heat transfer and other applications. Equations for the thermal conductivity of vapors at low pressure were formulated directly from a general equation fitted to the tabulated data of Bromley and Wilke.
T H E L I Q U I D A N D VAPOR VISCOSITY and thermal conductivity values of biphenyl and t h e three isomeric terphenyls were determined to provide data f o r use in heat t r a n s f e r calculations and engineering design of heat t r a n s f e r equipment. Because of their good radiation and thermal stability, t h e polyphenyls a r e useful as nuclear reactor coolants and in other high temperat u r e heat t r a n s f e r applications. T h e purity (12, 1 3 ) of the samples used in t h e viscosity and thermal conductivity measurements was : Biphenyl
99.95%
o-Terphenyl m-Terphenyl p-Terphenyl
99.9% 99.570 99.99%
The samples of biphenyl, 0-, and m-terphenyl were prepared by a n initial vacuum fractional distillation of commercial materials, and then these batches were refined f u r t h e r by repeated fractional freezing. T h e pterphenyl was purified by recrystallization f r o m benzene. The purity of these materials was checked by vapor phase chromatography w i t h a flame ionization detector. All experimental temperatures quoted were measured with platinum resistance thermometers which had been calibrated by the National Bureau of Standards. 1 Present address, Monsanto Enviro-Chem Systems, Inc., Box 8, Station B, Dayton, Ohio 45407 2 Present address, Aerospace Systems Division, Bendix Corp., 3300 Plymouth Road, Ann Arbor, Mich. 48107
122
Journal of Chemical and Engineering Data, Vol. 15, No. 1, 1970
VISCOSITY liquid Viscosity. The viscosities of liquid biphenyl, o-terphenyl, and m-terphenyl were measured on 1-ml. samples using a Cannon-Manning semimicroviscometer ; with p-terphenyl a Cannon-Ubbelohde semimicroviscometer was used. Viscosity measurements were made using constant temperature b a t h s controlled to *0.006" C. at 98.9" C. and i 0 . 0 2 " C. at higher temperatures. The viscometer calibration r u n s with water and the measurements on t h e polyphenyls were done in accordance with ASTM standard D 445-52T, and the observed kinematic viscosities a r e listed in Table I. These data a r e fitted to the following Andrade equations :
Biphenyl
log q
o-Terphenyl
log q
m-Terphenyl
log
p-Terphenyl
=
=
9 =
log Q
=
+ 634.8/T for 370 5 T 5480" K.
(1)
-2.4604
+ ll53.6/T for 370 5 T 5 560" K.
(2)
-2.0444
+ 977.0/T for 370 5 T 5 590" K.
(3)
-1.7080
-1.6965
+ 791.O/T for 4905T5620" K.
The kinematic viscosity values can be converted t o dynamic viscosities in centipoises b y multiplying by the following liquid densities, pL ( 5 , 11) : Biphenyl
p~
1.0145 - 0.0328 X 10-'t - 0.0138 X 1O-V for 100 St 5 450" C . (5)
Table IV. Viscosity Data for rn-Terphenyl
Table I. Viscosity of Liquid Biphenyl and the Terphenyls
Compound
Temp.,
Biphenyl o-Terphenyl
m-Terphenyl
p-Terphenyl
Dynamic Viscosity, Cp.
Viscosity, Centistokes
C.
~~
98.9 204.4
0.996 0.418
Temp., C.
This work
98.9 204.4 287.8
4.564 0.794 0.429
100
98.9 204.4 315.6
3.955 0.917 0.435
3.87 2.61 1.83 1.34
220.6 220.9 269.0 269.1 320.2 320.2 340.4
0.818
O
Andrews and Bowring Ubbelohde et al. (4)
Stone et al ( 2 4 )
(3)
125 150 175 200 225 250 275 300 325
0.799 0.571 0.573 0.434 0.436 0.393
3.62 2.30 1.55
1.01
0.78 0.61 0.49 0.40 0.34
2.98 1.66 1.21 0.91 0.72 0.58 0.49 0.41 0.35
2.15 1.55 1.16 0.89 0.70 0.57 0.47 0.39 0.33
Table V. Viscosity Data for p-Terphenyl
Dynamic Viscosity, CD. o-Terphenyl
1.087 - 0.068
p~ =
x
10-4t2 for
m-Terphenyl
p~ =
1.101
- 0.065 x
p-Terphenyl
PL =
1.089
- 0.052
10-2t - 0.0030
x
loost
