Compositions include compositions of 1,1,2,2,3,3,4,4-octafluorobutane and a hydrocarbon having from 3 to 7 carbon atoms. Specific examples include 1,1,2,2,3,3,4,4-octafluorobutane and butane, cyclopropane, isobutane, propane, cyclopentane, 2,2-dimethylbutane, n-pentane, 2-methylbutane, cyclohexane, 2,3-dimethylpentane, 3-ethylpentane, heptane, hexane or methylcyclopentane. Also included in this invention are compositions of 1,1,2,2,3,3,4,4-octafluorobutane and ethyl formate, propylene oxide, bis(pentafluoroethyl)sulfide, dimethoxyethane or tetrahydrofuran. These compositions, which may be azeotropic or azeotrope-like, may be used as refrigerants, cleaning agents, expansion agents for polyolefins and polyurethanes, aerosol propellants, refrigerants, heat transfer media, gaseous dielectrics, fire extinguishing agents, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, buffing abrasive agents or displacement drying agents.

FIELD OF THE INVENTION 
This invention relates to refrigerant compositions that include 
1,1,2,2,3,3,4,4-octafluorobutane. These compositions are useful as 
refrigerants, cleaning agents, expansion agents for polyolefins and 
polyurethanes, aerosol propellants, refrigerants, heat transfer media, 
gaseous dielectrics, fire extinguishing agents, power cycle working 
fluids, polymerization media, particulate removal fluids, carrier fluids, 
buffing abrasive agents, and displacement drying agents. 
BACKGROUND OF THE INVENTION 
Fluorinated hydrocarbons have many uses, one of which is as a refrigerant. 
Such refrigerants include trichlorofluoromethane (CFC-11) and 
chlorodifluoromethane (HCFC-22). 
In recent years it has been pointed out that certain kinds of fluorinated 
hydrocarbon refrigerants released into the atmosphere may adversely affect 
the stratospheric ozone layer. Although this proposition has not yet been 
completely established, there is a movement toward the control of the use 
and the production of certain chlorofluorocarbons (CFCs) and 
hydrochlorofluorocarbons (HCFCs) under an international agreement. 
Accordingly, there is a demand for the development of refrigerants that 
have a lower ozone depletion potential than existing refrigerants while 
still achieving an acceptable performance in refrigeration applications. 
Hydrofluorocarbons (HFCs) have been suggested as replacements for CFCs and 
HCFCs since HFCs have no chlorine and therefore have zero ozone depletion 
potential. 
In refrigeration applications, a refrigerant is often lost during operation 
through leaks in shaft seals, hose connections, soldered joints and broken 
lines. In addition, the refrigerant may be released to the atmosphere 
during maintenance procedures on refrigeration equipment. If the 
refrigerant is not a pure component or an azeotropic or azeotrope-like 
composition, the refrigerant composition may change when leaked or 
discharged to the atmosphere from the refrigeration equipment, which may 
cause the refrigerant to become flammable or to have poor refrigeration 
performance. 
Accordingly, it is desirable to use as a refrigerant a single fluorinated 
hydrocarbon or an azeotropic or azeotrope-like composition that includes a 
fluorinated hydrocarbon. 
Fluorinated hydrocarbons may also be used as a cleaning agent or solvent to 
clean, for example, electronic circuit boards. It is desirable that the 
cleaning agents be azeotropic or azeotrope-like because in vapor 
degreasing operations the cleaning agent is generally redistilled and 
reused for final rinse cleaning. 
Azeotropic or azeotrope-like compositions that include a fluorinated 
hydrocarbon are also useful as blowing agents in the manufacture of 
closed-cell polyurethane, phenolic and thermoplastic foams, as propellants 
in aerosols, as heat transfer media, gaseous dielectrics, fire 
extinguishing agents, power cycle working fluids such as for heat pumps, 
inert media for polymerization reactions, fluids for removing particulates 
from metal surfaces, as carrier fiuids that may be used, for example, to 
place a fine film of lubricant on metal parts, as buffing abrasive agents 
to remove buffing abrasive compounds from polished surfaces such as metal, 
as displacement drying agents for removing water, such as from jewelry or 
metal parts, as resist developers in conventional circuit manufacturing 
techniques including chlorine-type developing agents, or as strippers for 
photoresists when used with, for example, a chlorohydrocarbon such as 
1,1,1-trichloroethane or trichloroethylene. 
SUMMARY OF THE INVENTION 
The present invention relates to compositions of 
1,1,2,2,3,3,4,4-octafluorobutane (HFC-338pcc) and a hydrocarbon having 
from 3 to 7 carbon atoms. Specific examples include HFC-338pcc and butane, 
cyclopropane, isobutane, propane, cyclopentane, 2,2-dimethylbutane, 
n-pentane, 2-methylbutane, cyclohexane, 2,3-dimethylpentane, 
3-ethylpentane, heptane, hexane or methylcyclopentane. Also included in 
this invention are compositions of HFC-338pcc and ethyl formate, propylene 
oxide, bis(pentafluoroethyl)sulfide (3110S.beta..gamma.), dimethoxyethane 
or tetrahydrofuran (THF). These compositions are also useful as cleaning 
agents, expansion agents for polyolefins and polyurethanes, aerosol 
propellants, heat transfer media, gaseous dielectrics, fire extinguishing 
agents, power cycle working fluids, polymerization media, particulate 
removal fluids, carrier fluids, buffing abrasive agents, and displacement 
drying agents. Further, the invention relates to the discovery of binary 
azeotropic or azeotrope-like compositions comprising effective amounts of 
HFC-338pcc and a hydrocarbon having from 3 to 7 carbon atoms. Specific 
examples include HFC-338pcc and butane, cyclopropane, isobutane, propane, 
cyclopentane, 2,2-dimethylbutane, n-pentane, 2-methylbutane, cyclohexane, 
2,3-dimethylpentane, 3-ethylpentane, heptane, hexane or 
methylcyclopentane. Also included in this invention are compositions of 
HFC-338pcc and ethyl formate, propylene oxide, 3110S.beta..gamma., 
dimethoxyethane or THF to form an azeotropic or azeotrope-like composition 
.

DETAILED DESCRIPTION 
The present invention relates to compositions of HFC-338pcc and a 
hydrocarbon having from 3 to 7 carbon atoms. Specific examples include 
HFC-338pcc and butane, cyclopropane, isobutane, propane, cyclopentane, 
2,2-dimethylbutane, n-pentane, 2-methylbutane, cyclohexane, 
2,3-dimethylpentane, 3-ethylpentane, heptane, hexane or 
methylcyclopentane. Also included in this invention are compositions of 
HFC-338pcc and ethyl formate, propylene oxide, 3110S.beta..gamma., 
dimethoxyethane or THF. 
1-99 wt. % of each of the components of the compositions can be used as 
refrigerants. Further, the present invention also relates to the discovery 
of azeotropic or azeotrope-like compositions of effective amounts of each 
of the above mixtures to form an azeotropic or azeotrope-like composition. 
This invention includes the following components: 
1,1,2,2,3,3,4,4-octafluorobutane, CF.sub.2 HCF.sub.2 CF.sub.2 CF.sub.2 H, 
HFC-338pcc, boiling point=44.degree. C.; butane, CH.sub.3 (CH.sub.2).sub.2 
CH.sub.3, boiling point=0.degree. C.; cyclopropane, --CH.sub.2 CH.sub.2 
CH.sub.2 --, boiling point=-33.degree. C.; isobutane, CH.sub.3 
CH(CH.sub.3)CH.sub.3, boiling point=-12.degree. C.; propane, CH.sub.3 
CH.sub.2 CH.sub.3, boiling point=-42.degree. C.; cyclopentane, --CH.sub.2 
CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 --, boiling point=49.degree. C.; 
2,2-dimethylbutane, CH.sub.3 CH.sub.2 C(CH.sub.3).sub.2 CH.sub.3, boiling 
point=50.degree. C.; n-pentane, CH.sub.3 (CH.sub.2).sub.3 CH.sub.3, 
boiling point=36.degree. C.; 2-methylbutane, CH.sub.3 CH.sub.2 
CH(CH.sub.3)CH.sub.3, boiling point=28.degree. C.; ethyl formate, 
HCOOC.sub.2 H.sub.5, boiling point=54.degree. C.; propylene oxide, C.sub.3 
H.sub.60, boiling point=34.degree. C.; bis(pentafluoroethyl)sulfide, 
3110S.beta..gamma., C.sub.2 F.sub.5 SC.sub.2 F.sub.5, boiling 
point=37.degree. C.; cyclohexane, --CH.sub.3 CH.sub.2 CH.sub.2 CH.sub.2 
CH.sub.3 --, boiling point=80.7.degree. C.; 1,2-dimethoxyethane CH.sub.3 
OCH.sub.2 CH.sub.2 OCH.sub.3, boiling point=83.degree. C.; 
2,3-dimethylpentane, CH.sub.3 CH(CH.sub.3)CH(CH.sub.3)CH.sub.2 CH.sub.3, 
boiling point=90.degree. C.; 3-ethylpentane, CH.sub.3 CH.sub.2 CH(CH.sub.2 
CH.sub.3)C.sub.2 CH.sub.3, boiling point=93.degree. C.; heptane, CH.sub.3 
(CH.sub.2).sub.5 CH.sub.3, boiling point=98.4.degree. C.; hexane, CH.sub.3 
(CH.sub.2).sub.4 CH.sub.3, boiling point=69.degree. C.; 
methylcyclopentane, C.sub.6 H.sub.12, boiling point=72.degree. C.; and 
tetrahydrofuran, C.sub.4 H.sub.8 O, boiling point=66.degree. C. 
HFC-338pcc may be made by refluxing the potassium salt of perfluoroadipic 
acid in ethylene glycol as reported by Hudlicky, et. al. in J. Fluorine 
Chemistry, Vol. 59, pp. 9-14 (1992). 
3110S.beta..gamma. has been prepared by reaction of perfluoroethyl iodide 
with elemental sulfur at 300.degree. C. under pressure as disclosed by 
Tiers, Journal of Organic Chemistry, Vol. 26, page 3515 (1961). 
By "azeotropic" composition is meant a constant boiling liquid admixture of 
two or more substances that behaves as a single substance. One way to 
characterize an azeotropic composition is that the vapor produced by 
partial evaporation or distillation of the liquid has the same composition 
as the liquid from which it was evaporated or distilled, that is, the 
admixture distills/refluxes without compositional change. Constant boiling 
compositions are characterized as azeotropic because they exhibit either a 
maximum or minimum boiling point, as compared with that of the 
non-azeotropic mixtures of the same components. 
By "azeotrope-like" composition is meant a constant boiling, or 
substantially constant boiling, liquid admixture of two or more substances 
that behaves as a single substance. One way to characterize an 
azeotrope-like composition is that the vapor produced by partial 
evaporation or distillation of the liquid has substantially the same 
composition as the liquid from which it was evaporated or distilled, that 
is, the admixture distills/refluxes without substantial composition 
change. Another way to characterize an azeotrope-like composition is that 
the bubble point vapor pressure and the dew point vapor pressure of the 
composition at a particular temperature are substantially the same. 
It is recognized in the art that a composition is azeotrope-like if, after 
50 weight percent of the composition is removed such as by evaporation or 
boiling off, the difference in vapor pressure between the original 
composition and the composition remaining after 50 weight percent of the 
original composition has been removed is less than 10 percent, when 
measured in absolute units. By absolute units, it is meant measurements of 
pressure and, for example, psia, atmospheres, bars, tort, dynes per square 
centimeter, millimeters of mercury, inches of water and other equivalent 
terms well known in the art. If an azeotrope is present, there is no 
difference in vapor pressure between the original composition and the 
composition remaining after 50 weight percent of the original composition 
has been removed. 
Therefore, included in this invention are compositions of effective amounts 
of HFC-338pcc and butane, cyclopropane, isobutane, propane, cyclopentane, 
2,2-dimethylbutane, n-pentane, 2-methylbutane, ethyl formate, propylene 
oxide, 3110S.beta..gamma., cyclohexane, dimethoxyethane, 
2,3-dimethylpentane, 3-ethylpentane, heptane, hexane, methylcyclopentane 
or THF such that after 50 weight percent of an original composition is 
evaporated or boiled off to produce a remaining composition, the 
difference in the vapor pressure between the original composition and the 
remaining composition is 10 percent or less. 
For compositions that are azeotropic, there is usually some range of 
compositions around the azeotrope point that, for a maximum boiling 
azeotrope, have boiling points at a particular pressure higher than the 
pure components of the composition at that pressure and have vapor 
pressures at a particular temperature lower than the pure components of 
the composition at that temperatures, and that, for a minimum boiling 
azeotrope, have boiling points at a particular pressure lower than the 
pure components of the composition at that pressure and have vapor 
pressures at a particular temperature higher than the pure components of 
the composition at that temperature. Boiling temperatures and vapor 
pressures above or below that of the pure components are caused by 
unexpected intermolecular forces between and among the molecules of the 
compositions, which can be a combination of repulsive and attractive 
forces such as van der Waals forces and hydrogen bonding. 
The range of compositions that have a maximum or minimum boiling point at a 
particular pressure, or a maximum or minimum vapor pressure at a 
particular temperature, may or may not be coextensive with the range of 
compositions that have a change in vapor pressurize of less than about 10% 
when 50 weight percent of the composition is evaporated. In those cases 
where the range of compositions that have maximum or minimum boiling 
temperatures at a particular pressure, or maximum or minimum vapor 
pressures at a particular temperature, are broader than the range of 
compositions that have a change in vapor pressure of less than about 10% 
when 50 weight percent of the composition is evaporated, the unexpected 
intermolecular forces are nonetheless believed important in that the 
refrigerant compositions having those forces that are not substantially 
constant boiling may exhibit unexpected increases in the capacity or 
efficiency versus the components of the refrigerant composition. 
The components of the compositions of this invention have the following 
vapor pressures at 25.degree. C. 
______________________________________ 
COMPONENTS PSIA KPA 
______________________________________ 
HFC-338pcc 6.9 48 
3110S.beta..gamma. 9.5 66 
butane 35.2 243 
cyclopropane 105.0 724 
isobutane 50.5 348 
propane 137.8 950 
cyclopentane 6.1 42 
2,2-dimethylbutane 6.2 43 
n-pentane 10.3 71 
2-methylbutane 13.3 92 
ethyl formate 4.7 32 
propylene oxide 10.4 72 
cyclohexane 2.2 15 
dimethoxyethane 1.7 12 
2,3-dimethylpentane 
1.3 9 
3-ethylpentane 1.1 8 
heptane 0.9 6 
hexane 3.2 22 
methylcyclopentane 2.7 18 
THF 3.1 22 
______________________________________ 
Substantially constant boiling, azeotropic or azeotrope-like compositions 
of this invention comprise the following (all compositions are measured at 
25.degree. C.): 
______________________________________ 
WEIGHT 
RANGES PREFERRED 
COMPONENTS (wt. %/wt/%) 
(wt. %/wt. %) 
______________________________________ 
HFC-338pcc/butane 
1-70/30-99 20-70/30-80 
HFC-338pcc/cyclopropane 
1-60/40-99 1-60/40-99 
HFC-338pcc/isobutane 
1-68/32-99 20-68/32-80 
HFC-338pcc/propane 
1-64/36-99 1-64/36-99 
HFC-338pcc/cyclopentane 
47-88/12-53 47-88/12-53 
HFC-338pcc/2,2-dimethyl- 
46-86/14-54 46-86/14-54 
butane 
HFC-338pcc/n-pentane 
36-84/16-64 36-84/16-64 
HFC-338pcc/2-methylbutane 
33-79/21-67 33-79/21-67 
HFC-338pcc/ethyl formate 
53-99/1-47 53-99/1-47 
HFC-338pcc/propylene oxide 
1-94/6-99 40-94/6-60 
HFC-338pcc/3110S.beta..gamma. 
1-99/1-99 1-90/10-99 
HFC-338pcc/cyclohexane 
60-99/1-30 80-99/1-20 
HFC-338pcc/dimethoxyethane 
85-99/1-15 85-99/1-15 
HFC-338pcc/2,3-dimethyl- 
62-99/1-38 62-99/1-38 
pentane 
HFC-338pcc/3-ethylpentane 
63-99/1-37 63-99/1-37 
HFC-338pcc/heptane 
65-99/1-35 65-99/1-35 
HFC-338pcc/hexane 
56-93/7-44 56-93/7-44 
HFC-338pcc/methylcyclo- 
57-99/1-43 57-99/1-43 
pentane 
HFC-338pcc/THF 78-99/1-22 78-99/1-22 
______________________________________ 
For purposes of this invention, "effective amount" is defined as the amount 
of each component of the inventive compositions which, when combined, 
results in the formation of an azeotropic or azeotrope-like composition. 
This definition includes the amounts of each component, which amounts may 
vary depending on the pressure applied to the composition so long as the 
azeotropic or azeotrope-like compositions continue to exist at the 
different pressures, but with possible different boiling points. 
Therefore, effective amount includes the amounts, such as may be expressed 
in weight percentages, of each component of the compositions of the 
instant invention which form azeotropic or azeotrope-like compositions at 
temperatures or pressures other than as described herein. 
For the purposes of this discussion, azeotropic or constant-boiling is 
intended to mean also essentially azeotropic or essentially-constant 
boiling. In other words, included within the meaning of these terms are 
not only the true azeotropes described above, but also other compositions 
containing the same components in different proportions, which are true 
azeotropes at other temperatures and pressures, as well as those 
equivalent compositions which are part of the same azeotropic system and 
are azeotrope-like in their properties. As is well recognized in this art, 
there is a range of compositions which contain the same components as the 
azeotrope, which will not only exhibit essentially equivalent properties 
for refrigeration and other applications, but which will also exhibit 
essentially equivalent properties to tile true azeotropic composition in 
terms of constant boiling characteristics or tendency not to segregate or 
fractionate on boiling. 
It is possible to characterize, in effect, a constant boiling admixture 
which may appear under many guises, depending upon the conditions chosen, 
by any of several criteria: 
The composition can be defined as an azeotrope of A, B, C (and D . . . ) 
since the very term "azeotrope" is at once both definitive and limitative, 
and requires that effective amounts of A, B, C (and D . . . ) for this 
unique composition of matter which is a constant boiling composition. 
It is well known by those skilled in the art, that, at different pressures, 
the composition of a given azeotrope will vary at least to some degree, 
and changes in pressure will also change, at least to some degree, the 
boiling point temperature. Thus, an azeotrope of A, B, C (and D . . . ) 
represents a unique type of relationship but with a variable composition 
which depends on temperature and/or pressure. Therefore, compositional 
ranges, rather than fixed compositions, are often used to define 
azeotropes. 
The composition can be defined as a particular weight percent relationship 
or mole percent relationship of A, B, C (and D . . . ), while recognizing 
that such specific values point out only one particular relationship and 
that in actuality, a series of such relationships, represented by A, B, C 
(and D . . . ) actually exist for a given azeotrope, varied by the 
influence of pressure. 
An azeotrope of A, B, C (and D . . . ) can be characterized by defining the 
compositions as an azeotrope characterized by a boiling point at a given 
pressure, thus giving identifying characteristics without unduly limiting 
the scope of the invention by a specific numerical composition, which is 
limited by and is only as accurate as the analytical equipment available. 
The azeotrope or azeotrope-like compositions of the present invention can 
be prepared by any convenient method including mixing or combining the 
desired amounts. A preferred method is to weigh the desired component 
amounts and thereafter combine them in an appropriate container. 
Specific examples illustrating the invention are given below. Unless 
otherwise stated therein, all percentages are by weight. It is to be 
understood that these examples are merely illustrative and in no way are 
to be interpreted as limiting the scope of the invention. 
EXAMPLE 1 
Phase Study 
A phase study shows the following compositions are azeotropic. The 
temperature is 25.degree. C. 
______________________________________ 
Weight Vapor Press. 
Composition Percents psia kPa 
______________________________________ 
HFC-338pcc/butane 31.0/69.0 38.3 264 
HFC-338pcc/cyclopropane 
6.5/93.5 105.5 727 
HFC-338pcc/isobutane 
22.8/77.2 53.0 365 
HFC-338pcc/propane 
3.1/96.9 137.9 951 
HFC-338pcc/cyclopentane 
72.0/28.0 11.0 75 
HFC-338pcc/2,2-dimethylbutane 
70.5/29.5 11.8 81 
HFC-338pcc/n-pentane 
63.5/36.5 13.9 96 
HFC-338pcc/2-methylbutane 
54.2/45.8 18.1 124 
HFC-338pcc/ethyl formate 
79.3/20.7 8.5 58 
HFC-338pcc/propylene oxide 
55.0/45.0 10.6 73 
HFC-338pcc/3110S.beta..gamma. 
15.7/84.3 9.7 67 
HFC-338pcc/cyclohexane 
88.6/11.4 7.91 55 
HFC-338pcc/dimethoxyethane 
96.9/3.1 7.31 50 
HFC-338pcc/2,3-dimethylpentane 
91.7/8.3 7.67 53 
HFC-338pcc/3-ethylpentane 
93.0/7.0 7.48 52 
HFC-338pcc/heptane 
94.7/5.3 7.28 50 
HFC-338pcc/hexane 82.9/17.1 9.03 62 
HFC-338pcc/methylcyclopentane 
85.7/14.3 8.33 57 
HFC-338pcc/THF 93.6/6.4 7.56 52 
______________________________________ 
EXAMPLE 2 
Impact of Vapor Leakage on Vapor Pressure at 25.degree. C. 
A vessel is charged with an initial liquid composition at 25.degree. C. The 
liquid, and the vapor above the liquid, are allowed to come to 
equilibrium, and the vapor pressure in the vessel is measured. Vapor is 
allowed to leak from the vessel, while the temperature is held constant at 
25.degree. C., until 50 weight percent of the initial charge is removed, 
at which time the vapor pressure of the composition remaining in the 
vessel is measured. The results are summarized below. 
______________________________________ 
0 wt % 50 wt % 
Refrigerant 
evaporated evaporated 0% change in 
Composition 
psia kPa psia kPa vapor pressure 
______________________________________ 
HFC-338pcc/butane 
31.0/69.0 38.3 264 38.3 264 0.0 
15/85 38.0 262 36.8 254 3.2 
10/90 37.7 260 35.8 247 5.1 
5/95 37.0 255 35.3 244 4.5 
1/99 35.7 246 35.2 243 1.4 
50/50 38.1 263 37.9 261 0.7 
70/30 37.5 259 34.2 236 9.0 
71/29 37.5 258 33.6 232 10.3 
HFC-338pcc/cyclopropane 
6.5/93.5 105.5 727 105.5 727 0.0 
1/99 105.2 725 105.2 725 0.0 
30/70 104.7 722 103.8 716 0.8 
50/50 103.2 711 98.7 680 4.4 
60/40 101.5 700 91.6 632 9.7 
61/39 101.3 698 90.6 625 10.5 
HFC-338pcc/isobutane 
22.8/77.2 53.0 365 53.0 365 0.0 
10/90 52.7 363 51.8 357 1.6 
1/99 51.0 351 50.5 348 0.8 
60/40 52.3 361 50.4 347 3.7 
68/32 51.8 357 46.8 323 9.7 
69/31 51.8 357 46.0 317 11.1 
HFC-338pcc/propane 
3.1/96.9 137.9 951 137.9 951 0.0 
1/99 137.9 951 137.9 951 0.0 
20/80 136.9 944 136.3 940 0.5 
60/40 132.9 916 123.7 853 6.9 
64/36 132.0 910 118.9 820 9.9 
65/35 131.7 908 117.4 810 10.9 
HFC-338pcc/cyclopentane 
72.0/28.0 11.0 75 11.0 75 0.0 
85/15 10.8 74 10.3 71 4.7 
88/12 10.6 73 9.6 66 9.4 
89/11 10.6 73 9.4 64 11.5 
50/50 10.9 75 10.7 73 1.9 
47/53 10.9 75 10.3 71 5.4 
46/54 10.8 75 9.7 67 10.5 
HFC-338pcc/2,2-dimethylbutane 
70.5/29.5 11.8 81 11.8 81 0.0 
86/14 11.7 81 10.7 73 8.8 
87/13 11.7 80 10.2 70 12.5 
50/50 11.8 81 11.5 79 2.1 
46/54 11.8 81 10.8 74 8.4 
45/55 11.8 81 10.2 71 12.9 
HFC-338pcc/n-pentane 
63.5/36.5 13.9 96 13.9 96 0.0 
80/20 13.7 94 13.2 91 3.6 
84/16 13.6 94 12.3 85 9.6 
85/15 13.6 94 11.8 81 13.2 
40/60 13.6 94 12.7 88 6.6 
36/64 13.5 93 12.2 84 9.6 
35/65 13.5 93 12.1 83 10.4 
HFC-338pcc/2-methylbutane 
54.2/45.8 18.1 124 18.1 124 0.0 
33/67 18.0 124 16.6 114 7.9 
32/68 18.0 124 16.0 111 10.8 
80/20 17.8 123 15.6 107 12.5 
79/21 17.8 123 16.0 111 10.0 
HFC-338pcc/ethyl formate 
79.3/20.7 8.5 58 8.5 58 0.0 
90/10 8.3 57 8.1 56 2.4 
99/1 7.2 49 7.0 48 2.5 
60/40 8.3 57 8.0 55 3.7 
53/47 8.2 56 7.5 51 8.9 
52/48 8.2 56 7.4 51 10.0 
HFC-338pcc/propylene oxide 
55.0/45.0 10.60 73 10.60 73 0.0 
40/60 10.57 73 10.57 73 0.0 
20/80 10.50 72 10.50 72 0.0 
1/99 10.43 72 10.43 72 0.0 
80/20 10.37 71 10.29 71 0.7 
94/6 9.59 66 8.77 60 8.6 
95/5 9.47 65 8.25 57 12.9 
HFC-338pcc/3110S.beta..gamma. 
15.7/84.3 9.7 67 9.7 67 0.0 
1/99 9.5 66 9.5 66 0.0 
40/60 9.4 65 9.3 64 1.1 
60/40 8.9 62 8.6 59 3.7 
80/20 8.1 56 7.7 53 6.0 
90/10 7.6 52 7.2 50 5.0 
99/1 7.0 48 6.9 48 0.7 
HFC-338pcc/cyclohexane 
88.6/11.4 7.91 55 7.91 55 0.0 
99/1 7.24 50 6.97 48 3.7 
70/30 7.80 54 7.69 53 1.4 
60/40 7.75 53 7.31 50 5.7 
59/41 7.74 53 6.84 47 11.6 
HFC-338pcc/dimethoxyethane 
96.9/3.1 7.31 50 7.31 50 0.0 
99/1 7.29 50 6.88 47 5.6 
85/15 7.01 48 6.35 44 9.4 
84/16 6.97 48 6.21 43 10.9 
HFC-338pcc/2,3-dimethylpentane 
91.7/8.3 7.67 53 7.67 53 0.0 
99/1 7.30 50 6.93 48 5.1 
80/20 7.63 53 7.60 52 0.4 
70/30 7.61 52 7.53 52 1.1 
62/38 7.59 52 6.90 48 9.1 
61/39 7.59 52 6.41 44 15.5 
HFC-338pcc/3-ethylpentane 
93.0/7.0 7.48 52 7.48 52 0.0 
99/1 7.22 50 6.94 48 3.9 
80/20 7.44 51 7.40 51 0.5 
70/30 7.41 51 7.32 50 1.2 
63/37 7.40 51 6.67 46 9.9 
62/38 7.40 51 6.13 42 17.2 
HFC-338pcc/heptane 
94.7/5.3 7.28 50 7.28 50 0.0 
99/1 7.12 49 6.97 48 2.1 
80/20 7.22 50 7.17 49 0.7 
70/30 7.19 50 7.07 49 1.7 
65/35 7.18 50 6.65 46 7.4 
64/36 7.18 50 6.32 44 12.0 
HFC-338pcc/hexane 
82.9/17.1 9.03 62 9.03 62 0.0 
93/7 8.89 61 8.10 56 8.9 
94/6 8.83 61 7.76 54 12.1 
60/40 8.97 62 8.76 60 2.3 
56/44 8.96 62 8.09 56 9.7 
55/45 8.96 62 7.51 52 16.2 
HFC-338pcc/methylcyclopentane 
85.7/14.3 8.33 57 8.33 57 0.0 
95/5 8.10 56 7.59 52 6.3 
99/1 7.34 51 6.95 48 5.3 
57/43 8.20 57 7.57 52 7.7 
56/44 8.19 56 6.51 45 20.5 
HFC-338pcc/THF 
93.6/6.4 7.56 52 7.56 52 0.0 
99/1 7.27 50 6.99 48 3.9 
78/22 7.18 50 6.53 45 9.1 
77/23 7.14 49 6.42 44 10.1 
______________________________________ 
The results of this Example show that these compositions are azeotropic or 
azeotrope-like because when 50 wt. % of an original composition is 
removed, the vapor pressure of the remaining composition is within about 
10% of the vapor pressure of the original composition, at a temperature of 
25.degree. C. 
EXAMPLE 3 
Impact of Vapor Leakage at 0.degree. C. 
A leak test is performed on compositions of HFC-338pcc and THF, at the 
temperature of 0.degree. C. The results are summarized below. 
______________________________________ 
0 wt % 50 wt % 
Refrigerant 
evaporated evaporated 0% change in 
Composition 
psia kPa psia kPa vapor pressure 
______________________________________ 
HFC-338pcc/THF 
94.3/5.7 2.40 16.5 2.40 16.5 0.0 
99/1 2.33 16.1 2.23 15.4 4.3 
80/20 2.29 15.8 2.08 14.3 9.2 
79/21 2.28 15.7 2.05 14.1 10.1 
______________________________________ 
These results show that compositions of and are azeotropic or 
azeotrope-like at different temperatures, but that the weight percents of 
the components vary as the temperature is changed. 
EXAMPLE 4 
Refrigerant Performance 
The following table shows the performance of various refrigerants in an 
ideal vapor compression cycle. The data are based on the following 
conditions. 
______________________________________ 
Evaporator temperature 
40.0.degree. F. (4.4.degree. C.) 
Condenser temperature 
130.0.degree. F. (54.4.degree. C.) 
Liquid subcooled 5.degree. F. (2.8.degree. C.) 
Return Gas 60.degree. F. (15.6.degree. C.) 
Compressor efficiency is 70%. 
______________________________________ 
The refrigeration capacity is based on a compressor with a fixed 
displacement of 3.5 cubic feet per minute and 70% volumetric efficiency. 
Capacity is intended to mean the change in enthalpy of the refrigerant in 
the evaporator per pound of refrigerant circulated, i.e. the heat removed 
by the refrigerant in the evaporator per time. Coefficient of performance 
(COP) is intended to mean the ratio of the capacity to compressor work. It 
is a measure of refrigerant energy efficiency. 
______________________________________ 
Evap. Cond. Comp. Dis. Capacity 
Refrig. 
Press. Press. Temp. BTU/min 
Comp. Psia kPa Psia kPa .degree.F. .degree.C. 
COP kw 
______________________________________ 
HFC-338pcc/butane 
1/99 17.6 121 80.4 554 161.6 
72.0 2.99 76.2 1.3 
99/1 3.2 22 22.3 154 143.9 
62.2 3.00 18.0 0.3 
HFC-338pcc/cyclopropane 
1/99 57.1 394 214.4 
1478 211.2 
99.6 3.03 226.0 
4.0 
99/1 4.6 32 27.2 188 144.7 
62.6 3.56 27.6 0.5 
HFC-338pcc/isobutane 
1/99 26.1 180 109.7 
756 158.0 
70.0 2.87 101.6 
1.8 
99/1 3.3 23 22.6 156 143.5 
61.9 3.03 18.5 0.3 
HFC-338pcc/propane 
1/99 75.8 523 269.8 
1860 172.1 
77.8 2.63 235.2 
4.1 
99/1* 4.3 30 26.2 181 145.4 
63.0 3.42 25.2 0.4 
HFC-338pcc/cyclopentane 
1/99 2.6 18 17.2 119 159.3 
70.7 3.16 15.2 0.3 
99/1 3.1 21 21.3 147 143.9 
62.2 2.94 16.7 0.3 
HFC-338pcc/2,2-dimethylbutane 
1/99 2.7 19 16.8 116 137.7 
58.7 2.94 13.9 0.2 
99/1 3.0 21 20.9 144 143.6 
62.0 2.92 16.3 0.3 
HFC-338pcc/n-pentane 
1/99 4.4 30 26.6 183 155.7 
68.7 3.08 23.6 0.4 
99/1 3.2 22 22.1 152 143.3 
61.8 2.99 17.8 0.3 
HFC-338pcc/2-methylbutane 
1/99 6.0 41 33.2 229 148.2 
64.6 3.00 29.5 0.5 
99/1 3.0 21 21.3 147 143.9 
62.2 2.93 16.7 0.3 
HFC-338pcc/ethyl formate 
1/99 1.9 13 15.3 105 202.3 
94.6 3.62 14.7 0.3 
99/1 3.1 21 21.8 150 144.3 
62.4 2.97 17.3 0.3 
HFC-338pcc/propylene oxide 
1/99 4.5 31 28.1 194 199.0 
92.8 3.31 27.5 0.5 
99/1 3.3 23 22.3 154 144.1 
62.3 3.01 18.1 0.3 
HFC-338pcc/3110S.beta..gamma. 
1/99* 3.9 27 26.7 184 132.8 
56.0 2.61 18.5 0.3 
99/1 3.0 21 21.0 145 143.7 
62.1 2.92 16.3 0.3 
HFC-338pcc/cyclohexane 
60/40 1.5 10 12.7 88 151.2 
66.2 3.19 10.1 0.2 
99/1 3.0 21 20.8 143 213.7 
100.9 
3.23 14.3 0.3 
HFC-338pcc/dimethoxyethane 
60/40 1.4 10 12.9 89 164.0 
73.3 3.28 9.9 0.2 
99/1 3.0 21 20.9 144 144.0 
62.2 2.93 16.3 0.3 
HFC-338pcc/2,3-dimethylpentane 
60/40 0.7 5 7.0 48 147.2 
64.0 3.21 5.2 0.1 
99/1 2.5 17 19.0 131 147.4 
64.1 2.91 14.1 0.2 
HFC-338pcc/3-ethylpentane 
60/40 0.9 6 8.9 61 146.8 
63.8 3.25 6.7 0.1 
99/1 2.8 19 20.2 139 144.4 
62.4 2.92 15.6 0.3 
HFC-338pcc/heptane 
60/40 0.8 6 8.1 56 148.5 
64.7 3.31 6.1 0.1 
99/1 2.8 19 20.1 139 144.7 
62.6 2.93 15.4 0.3 
HFC-338pcc/hexane 
1/99 1.1 8 9.1 63 147.6 
64.2 3.21 7.3 0.1 
99/1 2.9 20 20.7 143 143.8 
62.1 2.93 16.1 0.3 
HFC-338pcc/methylcyclopentane 
1/99 1.1 8 8.4 58 151.4 
66.3 3.13 6.7 0.1 
99/1 3.0 21 20.8 143 145.7 
63.2 2.95 16.3 0.3 
HFC-338pcc/THF 
60/40 2.5 17 19.6 135 165.4 
74.1 3.16 16.0 0.3 
99/1 3.1 21 21.4 148 144.1 
62.3 2.94 16.8 0.3 
______________________________________ 
*65.degree. F. Return Gas 
EXAMPLE 5 
This Example is directed to measurements of the liquid/vapor equilibrium 
curves for the mixtures in FIGS. 1-6 and 8-19. 
Turning to FIG. 1, the upper curve represents the composition of the 
liquid, and the lower curve represents the composition of the vapor. 
The data for the compositions of the liquid in FIG. 1 are obtained as 
follows. A stainless steel cylinder is evacuated, and a weighed amount of 
HFC-338pcc is added to the cylinder. The cylinder is cooled to reduce the 
vapor pressure of HFC-338pcc, and then a weighed amount of butane is added 
to the cylinder. The cylinder is agitated to mix the HFC-338pcc and 
butane, and then the cylinder is placed in a constant temperature bath 
until the temperature comes to equilibrium at 25.degree. C., at which time 
the vapor pressure of the HFC-338pcc and butane in the cylinder is 
measured. Additional samples of liquid are measured the same way, and the 
results are plotted in FIG. 1. 
The curve which shows the composition of the vapor is calculated using an 
ideal gas equation of state. 
Vapor/liquid equilibrium data are obtained in the same way for the mixtures 
shown in FIGS. 2-6 and 8-19. 
The data in FIGS. 1-6 and 8-19 show that at 25.degree. C., there are ranges 
of compositions that have vapor pressures higher than the vapor pressures 
of the pure components of the composition at that same temperature. As 
stated earlier, the higher than expected pressures of these compositions 
may result in an unexpected increase in the refrigeration capacity or 
efficiency for these compositions versus the pure components of the 
compositions. 
EXAMPLE 6 
This Example is directed to measurements of the liquid/vapor equilibrium 
curve for mixtures of HFC-338pcc and n-pentane. The liquid/vapor 
equilibrium data for these mixtures are shown in FIG. 7. The upper curve 
represents the liquid composition, and the lower curve represents the 
vapor composition. 
The procedure for measuring the composition of the liquid for mixtures of 
HFC-338pcc and n-pentane in FIG. 7 was as follows. A stainless steel 
cylinder was evacuated, and a weighed amount of HFC-338pcc was added to 
the cylinder. The cylinder was cooled to reduce the vapor pressure of 
HFC-338pcc, and then a weighed amount of n-pentane was added to the 
cylinder. The cylinder was agitated to mix the HFC-338pcc and n-pentane, 
and then the cylinder was placed in a constant temperature bath until the 
temperature came to equilibrium at 18.33.degree. C., at which time the 
vapor pressure of the content of the cylinder was measured. Samples of the 
liquid in the cylinder were taken and analyzed, and the results are 
plotted in FIG. 7 as asterisks, with a best fit curve having been drawn 
through the asterisks. 
This procedure was repeated for various mixtures of HFC-338pcc and 
n-pentane as indicated in FIG. 7. 
The curve which shows the composition of the vapor is calculated using an 
ideal gas equation of state. 
The data in FIG. 7 show that at 18.33.degree. C., there are ranges of 
compositions that have vapor pressures higher than the vapor pressures of 
the pure components of the composition at that same temperature. 
The novel compositions of this invention, including the azeotropic or 
azeotrope-like compositions, may be used to produce refrigeration by 
condensing the compositions and thereafter evaporating the condensate in 
the vicinity of a body to be cooled. The novel compositions may also be 
used to produce heat by condensing the refrigerant in the vicinity of the 
body to be heated and thereafter evaporating the refrigerant. 
The compositions of the present inventions are useful as blowing agents in 
the production of thermoset foams, which include polyurethane and phenolic 
foams, and thermoplastic foams, which include polystyrene or polyolefin 
foams. 
A polyurethane foam may be made by combining a composition of the present 
invention, which functions as a blowing agent, together with an 
isocyanate, a polyol, and appropriate catalysts or surfactants to form a 
polyurethane or polyisocyanurate reaction formulation. Water may be added 
to the formulation reaction to modify the foam polymer as well as to 
generate carbon dioxide as an in-situ blowing agent. 
A phenolic foam may be produced by combining a phenolic resin or resole, 
acid catalysts, a blowing agent of the present invention and appropriate 
surfactants to form a phenolic reaction formulation. The formulation may 
be chosen such that either an open cell or closed cell phenolic foam is 
produced. 
Polystyrene or polyolefin foams may be made by extruing a molten mixure of 
a polymer, such as polystyrere, polyethylene or polypropylene), a 
nucleating agent and a blowing agent of the present invention through an 
extrusion die that yields the desired foam product profile. 
The novel compositions of this invention, including the azeotropic or 
azeotrope-like compositions, may be used as cleaning agents to clean, for 
example, electronic circuit boards. Electronic components are soldered to 
circuit boards by coating the entire circuit side of the board with flux 
and thereafter passing the flux-coated board over preheaters and through 
molten solder. The flux cleans the conductive metal parts and promotes 
solder fusion, but leave residues on the circuit boards that must be 
removed with a cleaning agent. This is conventionally done by suspending a 
circuit board to be cleaned in a boiling sump which contains the 
azeotropic or azeotrope-like composition, then suspending the circuit 
board in a rinse sump, which contains the same azeotropic or 
azeotrope-like composition, and finally, for one minute in the solvent 
vapor above the boiling sump. 
As a further example, the azeotropic mixtures of this invention can be used 
in cleaning processes such as described in U.S. Pat. No. 3,881,949, or as 
a buffing abrasive detergent. 
It is desirable that the cleaning agents be azeotropic or azeotrope-like so 
that they do not tend to fractionate upon boiling or evaporation. This 
behavior is desirable because if the cleaning agent were not azeotropic or 
azeotrope-like, the more volatile components of the cleaning agent would 
preferentially evaporate, and would result in a cleaning agent with a 
changed composition that may become flammable and that may have 
less-desirable solvency properties, such as lower rosin flux solvency and 
lower inertness toward the electrical components being cleaned. The 
azeotropic character is also desirable in vapor degreasing operations 
because the cleaning agent is generally redistilled and employed for final 
rinse cleaning. 
The novel compositions of this invention are also useful as fire 
extinguishing agents. 
In addition to these applications, the novel constant boiling or 
substantially constant boiling compositions of the invention are also 
useful as aerosol propellants, heat transfer media, gaseous dielectrics, 
and power cycle working fluids. 
ADDITIONAL COMPOUNDS 
Other components, such as aliphatic hydrocarbons having a boiling point of 
-60.degree. to +60.degree. C., hydrofluorocarbonalkanes having a boiling 
point of -60.degree. to +60.degree. C., hydrofluoropropanes having a 
boiling point of between -60.degree. to +60.degree. C., hydrocarbon esters 
having a boiling point between -60.degree. to +60.degree. C., 
hydrochlorofluorocarbons having a boiling point between -60.degree. to 
+60.degree. C., hydrofluorocarbons having a boiling point of -60+ to 
+60.degree. C., hydrochlorocarbons having a boiling point between 
-60.degree. to +60.degree. C., chlorocarbons and perfluorinated compounds, 
can be added to the azeotropic or azeotrope-like compositions described 
above. 
Additives such as lubricants, corrosion inhibitors, surfactants, 
stabilizers, dyes and other appropriate materials may be added to the 
novel compositions of the invention for a variety of purposes provides 
they do not have an adverse influence on the composition for its intended 
application. Preferred lubricants include esters having a molecular weight 
greater than 250.