Density, viscosity, and vapor pressure of dichlorophenylphosphine sulfide

Article abstract of DOI:10.1021/je600566v

The density and viscosity of dichlorophenylphosphine sulfide (C ₆H₅PSCl₂) over a temperature range of (303.16 to 423.40) K were measured. The vapor pressure of dichlorophenylphosphine sulfide in the range of (417.83 to 448.12) K were measured by a static method. The density data were fitted to a second-order polynomial, the viscosity data were fitted to the Andrade equation, and the results of vapor pressure data were fitted to the Antoine equation. The density data and vapor pressure data of dichlorophenylphosphine sulfide were compared with literature values.

Full text of DOI:10.1021/je600566v

986
J. Chem. Eng. Data 2007, 52, 986-988
Density, Viscosity, and Vapor Pressure of Dichlorophenylphosphine Sulfide
Ting-Ting Guo, Jun-Sheng Wu,* Li-Sheng Wang, and Mi-Yi Li
School of Chemical Engineering & the Environment, Beijing Institute of Technology,
Beijing 100081, People’s Republic of China
The density and viscosity of dichlorophenylphosphine sulfide (C6H5PSCl2) over a temperature range of (303.16
to 423.40) K were measured. The vapor pressure of dichlorophenylphosphine sulfide in the range of (417.83 to
448.12) K were measured by a static method. The density data were fitted to a second-order polynomial, the
viscosity data were fitted to the Andrade equation, and the results of vapor pressure data were fitted to the Antoine
equation. The density data and vapor pressure data of dichlorophenylphosphine sulfide were compared with literature
values.
Table 1. Density of DCPPS
Introduction
T/K
F/g‚cm-3
100 δa
T/K
F/g‚cm-3
100 δa
Dichlorophenylphosphine sulfide (DCPPS, C6H5PSCl2) is an
intermediate for the production of bis(4-carboxyphenyl)phenyl
phosphine oxide, a halogen-free flame-retarding monomer that
can be chemically incorporated into various macromolecules
to produce flame-retarding polymers.1 In general, DCPPS is
widely used in the preparation of flame retardants, insecticides,
and plasticizers.2
303.16
313.12
323.25
332.85
343.00
353.19
363.25
1.3818
1.3742
1.3593
1.3565
1.3443
1.3291
1.3084
-0.234
-0.002
-0.238
0.424
0.499
0.411
374.75
383.20
393.26
403.85
412.65
423.40
1.2841
1.2760
1.2609
1.2370
1.2324
1.2106
-0.588
-0.173
-0.051
-0.501
0.410
0.278
-0.056
Although commercially available, the density, viscosity, and
vapor pressure of DCPPS in a range of operating temperatures,
which are very important and necessary for the design of
industrial processes, are not available in the literature. Up to
now, the density value of DCPPS at 293.15 K (F ) 1.4042
g‚cm-3)3 and 298.15 K (F ) 1.390 g‚cm-3)2 were reported.
The boiling temperatures of DCPPS at 3.47 kPa,4 0.67 kPa,5
0.27-0.40 kPa,6,7 and 0.08 kPa3 were reported in the literature.
In this paper, the density and viscosity of DCPPS are
presented in the range of (303.16 to 423.40) K, respectively,
and the results of density were compared with the literature
values. The vapor pressure of DCPPS in the range of (417.83
to 448.12) K, were measured by a static method and correlated
to the Antoine equation. A comparison was made with reported
values as mentioned above.
a 100 δ ) 100(F - Fcalc)/F.
measurements in the range of (363.25 to 423.40) K. The mass
was determined on an electronic balance with a precision of (
0.1 mg. The picnometer was then immersed in a thermostat bath
with temperature control precision of ( 0.01 K. The measured
densities of DCPPS are listed in Table 1. The densities of pure
water and ethylene glycol are obtained from the literature.10 The
estimated uncertainty in density was ( 5 × 10-4 g‚cm-3
.
Viscosity Measurements. An Ubbelohde capillary viscometer
was used to measure the viscosity. The capillary was calibrated
(including a kinetic energy correction term) with pure water in
the corresponding experimental temperature range. The kine-
matic viscosity is expressed as a function of two constants (k1,
k2) and the flow time t:
Experimental Section
V ) k1t - k2/t
(1)
Chemicals. DCPPS was synthesized from PCl3, benzene, and
sulfur in our laboratory following the procedure described by
Wang et al.2 Then it was distilled under reduced pressure (2.67
kPa). The purity of DCPPS after distillation was 99.9 % (mass)
determined by a gas chromatography test. The refractive index
value was obtained at 20 °C on an Abbe model refractometer
with an uncertainty of ( 0.0001 nD. The measured value was
The kinematic viscosity V for calibration was obtained from
literature values of the absolute viscosity and density.11 The
capillary was 0.55 mm in diameter and 40 mm in length;
therefore, the end correction could be neglected. The same
viscometer was used for all measurements.
The temperature control setup used was identical to that used
for density measurements described earlier. The flow time t was
recorded with a stopwatch of precision 0.01 S. Each measure-
ment was repeated 10 times and averaged as the final result.
The measurement uncertainty was within ( 0.1 S (( 0.33 % at
the high end of temperature). The density values used to convert
kinematic viscosity to absolute values were calculated from the
fitted equation. The measured viscosities of DCPPS over a range
of temperature are listed in Table 2. The measured flow time
was in the range of (80.72 to 172.38) S; the estimated
uncertainty in viscosity was within ( 0.5 %.
20
nD ) 1.6179, which agrees with the values in the literature
(nD20 ) 1.6227,8,9 nD20 ) 1.61765). Ethylene glycol purchased
from Beijing Chemical Reagent Company was an analytical
reagent.
Density Measurements. A 10 cm3 picnometer calibrated with
deionized and double-distilled water was used for the measure-
ments in the range of (303.16 to 353.19) K. The same
picnometer calibrated with ethylene glycol was used for the
* Corresponding author. E-mail: jswu@public3.bta.net.cn.
10.1021/je600566v CCC: $37.00 © 2007 American Chemical Society
Published on Web 04/11/2007

Journal of Chemical and Engineering Data, Vol. 52, No. 3, 2007 987
Table 3. Vapor Pressure Data of DCPPS
T/K
p/kPa
100 δa
T/K
p/kPa
100 δa
417.8
420.0
423.1
425.1
427.9
430.4
433.1
2.77
3.15
3.47
3.90
4.26
4.65
5.21
0.60
-2.64
0.99
-2.08
0.90
435.4
438.1
440.8
443.3
445.9
448.1
5.97
6.45
7.34
8.10
8.95
9.77
-1.81
1.47
-0.71
-0.76
-0.40
-0.48
2.65
2.44
a 100 δ ) 100(p - pcalc)/p.
Figure 1. Apparatus for the measurement of vapor pressure: 1, equilibrium
cell; 2, condenser; 3, temperature indicator; 4, thermoregulator; 5, agitator
blade; 6, to mercury pressure gauge; 7, buffer bottle; 8, nitrogen cylinder;
9, to vacuum pump; 10, thermostat bath.
Table 4. Antoine Constants for DCPPS
Antoine constants
temperature range
K
A
B
C
100 AAD
1.38
Table 2. Viscosity of DCPPS
T/K
η/mPa‚s
100 δa
T/K
η/mPa‚s
100 δa
9.198
4011
40.45
417.8-448.1
303.16
313.12
323.25
332.85
343.00
353.19
363.25
3.634
2.957
2.439
2.082
1.791
1.556
1.356
3.849
1.100
374.75
383.20
393.26
403.85
412.65
423.40
1.199
1.082
0.972
0.872
0.798
0.729
-0.037
-0.358
0.270
0.766
0.770
pressure data for DCPPS in the range of (417.83 to 448.12) K
are listed in Table 3.
-1.175
-1.892
-1.865
-1.651
-2.084
DCPPS is a slightly yellowish transparent liquid at ambient
temperature. When the temperature was raised to 448.12 K, the
color of the sample began to change and became yellowish
brown. This phenomenon indicates that the DCPPS will
decompose above this temperature.
2.171
a 100 δ ) 100(η - ηcalc)/η.
Vapor Pressure Measurements. The vapor pressure was
measured by a static method. The apparatus setup is schemati-
cally shown in Figure 1. It consists of a temperature control
and measurement system, a vacuum pump, and a pressure-
measurement system. An equilibrium cell with a U-type tube
construction for the judgment of pressure balance, as shown in
Figure 1, containing the liquid sample was immersed in the
thermostat silicon oil bath. The temperature of the oil bath was
controlled automatically by a YCC-16 intelligent controller to
( 0.1 K. In the pressure measurements, a U-type mercury
pressure gauge was used, and the height difference was
measured by a cathetometer. The measured pressures were
corrected by a barometer. The accuracy of the pressure
measurements was better than 0.013 kPa.
The apparatus setup had been tested by measuring the vapor
pressure of pure water from (293.15 to 353.15) K and by
comparing the results with literature values.10 The deviations
between the experimental results and the literature values were
within ( 0.2 %, which showed the apparatus to be reliable.
The equilibrium cell was made of thin-walled glass to aid
the sample to reach rapid temperature equilibrium with the
surrounding silicon oil bath. Before setting the equilibrium cell
in the thermostat bath, it was necessary to degas the sample
thoroughly. The liquid sample was degassed by repeated freeze-
evacuate-thaw cycles. After degassing, the equilibrium cell was
immersed in the thermostat bath and connected to the vacuum
system with a condenser in between. Along with the evacuation
process, the space in the U-type tube of the equilibrium cell
was filled with pure vapor of the liquid sample. At each selected
temperature, evacuation was conducted continuously until the
liquid sample in the equilibrium cell began to boil, then the
nitrogen gas was filled into the vacuum system carefully to
adjust the system pressure to equal the vapor pressure of the
sample by observing the liquid levels in the U-type tube of the
equilibrium cell. The temperature and the pressure were recorded
and corrected correspondingly. The operation was repeated
seven to eight times at each temperature, and an averaged value
was adopted. The maximum deviation between the individual
measured values for each temperature was within ( 0.05 %.
The vapor pressure measurement versus temperature was
performed in every (2-5) K intervals. The experimental vapor
Results and Discussion
Results. The measured data of the density, viscosity, and
vapor pressure of DCPPS were fitted to the following equations.
Density versus temperature was fitted to a second-order
polynomial:
F/g‚cm-3 ) 1.372 + 1.130 ×
10-3(T/K) - 3.590 × 10-6(T/K)2 (2)
Viscosity versus temperature was fitted to the Andrade equation:
ln(η/mPa‚S) ) -4.346 + 1697/(T/K)
(3)
Vapor pressure versus temperature was fitted to the Antoine
equation:
B
log(p/kPa) ) A -
(4)
C + T/K
where p is the vapor pressure; T is the temperature; and A, B,
and C are the Antoine constants.
The Antoine constants A, B, and C determined from least-
squares fitting and the absolute average deviation are listed in
Table 4. A comparison of the vapor pressure obtained from the
fitted equation and the measured data and the literature values
is shown in Figure 2.
The absolute average deviation (AAD) of measured data from
the fitted equation is defined as
1
N
AAD(F) )
AAD(η) )
AAD(p) )
|Fi - Fi,calc|/Fi
|ηi - ηi,calc|/ηi
|pi - pi,calc|/pi
(5)
(6)
(7)
∑
1
N
∑
∑
1
N
where the suffix calc stands for the calculated values from fitted
equations. The absolute average deviation of density, viscosity,

988 Journal of Chemical and Engineering Data, Vol. 52, No. 3, 2007
at (0.27 to 0.40) kPa, and (76 to 77) °C at 0.08 kPa, respectively,
which are beyond the temperature range of these experimental
measurements. The boiling temperatures calculated from eq 6
are 114.55 °C at 0.67 kPa, 97.12 °C at 0.27 kPa, and 76.04 °C
at 0.08 kPa, respectively, which could be regarded as a useful
reference.
Literature Cited
(1) Wang, L.-S.; Wang, X.-L. Solubilities of dichlorophenylphosphine
sulfide and bis(4-carboxyphenyl)phenylphosphine oxide in water. J.
Chem. Eng. Data 2000, 45, 743-745.
(2) Wang, L.-S.; Kang, H.-B.; Wang, Z.-W.; Wang, C.-G. Green synthesis
of dichiorophenylphosphine sulfide using chioroaluminate ionic liquids
as a catalyst. Phosphorus, Sulfur, Silicon Relat. Elem. 2007, 182, 1-10.
(3) Kabachnik, M. I.; Godovikov, N. N. Synthesis of chlorides of
thiophosphonic and thiophosphinic acids. Doklady Akad. Nauk S.S.S.R.
1956, 110, 217-219; Chem. Abstr. 1957, 51, 4982i.
Figure 2. Experimental and calculated vapor pressure data for DCPPS:
b, experimental data; s, calculated by eq 4.
(4) Welton, T. Room-temperature ionic liquids solvents for synthesis and
catalysis. Chem. ReV. 1999, 99 (8), 2071-2083.
(5) Giichi, F.; Hirosuke, Y.; Mitsuo, U. Oranic thionophosphonyl halide.
Japan Patent 2322(’62), 1962; Chem. Abstr. 1962, 58, 7976f.
(6) Jensen, W. L. Organic thionophosphorus compounds. U.S. Patent
2662917, 1953.
and vapor pressure fitting for DCPPS are (0.3, 1.4, and 1.38)
%, respectively.
(7) Hideo, A.; Toshiro, k.; Yasuo, H. Aromatic thionophosphonyl dichlo-
ride. Japan Patent 2925(’60), 1960; Chem. Abstr. 1960, 54, 24551f.
(8) Ludwig, M. Organic phosphorous compounds. XI. Arylation of PSCl3
in the presence of Friedel-Crafts activators. A new procedure for the
preparation of thiophosphonic dihalides, thiophosphinic halides, and
tertiary phosphine sulfides. HelV. Chim. Acta 1964, 47, 120-132.
(9) Ludwig, M. Aryl thiophosphorous compounds. German Patent 1238024,
1967.
(10) Weast, R. C. CRC Handbook of Chemistry and Physics, 63rd ed.;
CRC Press: Boca Raton, FL, 1982-1983.
(11) Perry, R. H.; Green, D. W.; Malone, J. O. Perry’s Chemical Engineers
Handbook, 6th ed.; McGraw-Hill: New York, 1984.
Discussion
The densities of DCPPS calculated from eq 2 at (293.15 and
298.15) K are (1.3947 and 1.3898) g‚cm-3, which are in good
agreement with the literature values of 1.4042 g‚cm-3 at 293.15
K3 and 1.390 g‚cm-3 at 298.15 K.2 While the viscosity data
over a temperature range of (303.16 to 423.40) K were fitted
to the Andrade equation, no literature values are available.
Welton4 reported the boiling temperature of 150 °C at 3.47
kPa. Compared with the data of this work, 423.10 K(150.10
°C) at 3.47 kPa, they are in fairly good agreement. In addition,
Giichi et al.,5 Warren,6 and Kabachnik and Godovikov3 reported
the boiling temperatures of 115 °C at 0.67 kPa, (95 to 110) °C
Received for review December 13, 2006. Accepted March 4, 2007.
JE600566V