Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
REFRIGERANT COMPOSITIONS INCLUDING HEXAFLUOROPROPANE AND A HYDROFLUOROCARBON
Document Type and Number:
WIPO Patent Application WO/1994/022973
Kind Code:
A1
Abstract:
This invention relates to compositions of a hexafluoropropane and a hydrofluorocarbon, with the hydrofluorocarbon being hexafluoropropane, pentafluoropropane, tetrafluoropropane, trifluoropropane, difluoropropane, fluoropropane, or (CF3)2CHCH3. The compositions, which may be azeotropic or azeotrope-like, may be used as refrigerants, 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 or displacement drying agents.

Inventors:
CHISOLM TUNEEN E C
MINOR BARBARA HAVILAND
Application Number:
PCT/US1994/003149
Publication Date:
October 13, 1994
Filing Date:
March 28, 1994
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
DU PONT (US)
International Classes:
C11D7/30; A62D1/00; C07C19/08; C08J9/14; C09K3/00; C09K3/30; C09K5/04; C11D7/50; (IPC1-7): C09K5/04; C08J9/14; C09K3/30
Domestic Patent References:
WO1991005585A11991-05-02
Foreign References:
US5254309A1993-10-19
Other References:
DATABASE WPI Section Ch Week 9340, Derwent World Patents Index; Class A21, AN 93-317625
PATENT ABSTRACTS OF JAPAN vol. 018, no. 068 (C - 1161) 4 February 1994 (1994-02-04)
PATENT ABSTRACTS OF JAPAN vol. 003, no. 032 (C - 040) 17 March 1979 (1979-03-17)
Download PDF:
Claims:
CLAIMS
1. A refrigerant composition comprising 1,1,2,2,3,3 hexafluoropropane and 1,1,1,3,3,3hexafluoropropane, 1,1,1,2,3pentafluoropropane, 1, 1, 1,3,3pentafluoropropane, 1, 1, 1,2tetrafluoropropane, 1,2,2trifluoropropane, 1,1,1trifluoropropane, 2,2difluoropropane, 1,1difluoropropane, 2fluoropropane or (CF3)2CHCH3; 1,1,1,2,2,3hexafluoropropane and 1,1,2,3,3,3hexafluoropopane, 1,1,1,3,3,3hexafluoropropane, 1,1,1,3,3pentafluoropropane, 1,1,2,2 tetrafluoropropane, 1,1,1,2tetrafluoropropane, 1,1,1trifluoropropane, 2,2 difluoropropane, 1,1difluoropropane, 2fluoropropane or lfluoropropane; 1,1,2,3,3,3hexafluoropopane and 1,1,1,3,3,3hexafluoropropane, 1,1,1,2,2 pentafluoropropane, 1,1,1trifluoropropane, 2,2difluoropropane, 1,1 difluoropropane, 2fluoropropane or lfluoropropane; 1,1,1,3,3,3hexafluoropropane and 1,1,2,2,3pentafluoropropane, 1,1,1,2,3pentafluoropropane, 1,2,2,3 tetrafluoropropane, 1,1,2,2tetrafluoropropane, 1,1,1,2tetrafluoropropane, 2,2 difluoropropane, 1,2difluoropropane, 2fluoropropane or lfluoropropane.
2. Effective amounts of the following compounds to form an azeotropic or azeotropelike composition: 1,1,2,2,3,3hexafluoropropane and 1, 1, 1,3,3 ,3hexafluoropropane, 1, 1, 1,2,3pentafluoropropane, 1, 1, 1,3,3 pentafluoropropane, 1,1,1,2tetrafluoropropane, 1,2,2trifluoropropane, 1,1,1 trifluoropropane, 2,2difluoropropane, 1,1difluoropropane, 2fluoropropane or (CF3)2CHCH3; 1,1,1,2,2,3hexafluoropropane and 1,1,2,3,3,3hexafluoropopane, 1,1,1,3,3,3hexafluoropropane, 1,1,1,3,3pentafluoropropane, 1,1,2,2 tetrafluoropropane, 1,1,1,2tetrafluoropropane, 1,1,1trifluoropropane, 2,2 difluoropropane, 1,1difluoropropane, 2fluoropropane or lfluoropropane; 1,1,2,3,3,3hexafluoropopane and 1,1,1,3,3,3hexafluoropropane, 1,1,1,2,2 pentafluoropropane, 1,1,1trifluoropropane, 2,2difluoropropane, 1,1 difluoropropane, 2fluoropropane or lfluoropropane; 1,1,1,3,3,3hexafluoropropane and 1,1,2,2,3pentafluoropropane, 1,1,1,2,3pentafluoropropane, 1,2,2,3 tetrafluoropropane, 1,1,2,2tetrafluoropropane, 1,1,1,2tetrafluoropropane, 2,2 difluoropropane, 1,2difluoropropane, 2fluoropropane or lfluoropropane.
3. The azeotropic or azeotropeUke composition of Claim 2, said composition comprising: 199 weight percent 1,1,2,2,3,3hexafluoropropane and 199 weight percent 1,1,1,3,3,3hexafluoropropane; 199 weight percent 1,1,2,2,3,3 hexafluoropropane and 199 weight percent 1,1,1,2,3pentafluoropropane; 199 weight percent 1,1,2,2,3,3hexafluoropropane and 199 weight percent 1,1,1,3,3 pentafluoropropane; 199 weight percent 1,1,2,2,3,3hexafluoropropane and 199 weight percent 1,1,1,2tetrafluoropropane; 199 weight percent 1,1,2,2,3,3 hexafluoropropane and 199 weight percent 1,2,2trifluoropropane; 162 weight percent 1,1,2,2,3,3hexafluoropropane and 3899 weight percent 1,1,1 trifluoropropane; 181 weight percent 1,1,2,2,3,3hexafluoropropane and 1999 weight percent 2,2difluoropropane; 199 weight percent 1,1,2,2,3,3 hexafluoropropane and 199 weight percent 1,1 difluoropropane; 178 weight percent 1,1,2,2,3,3hexafluoropropane and 2299 weight percent 2fluoropropane; 1 99 weight percent 1,1,2,2,3,3hexafluoropropane and 199 weight percent (CF3)2CHCH3; 199 weight percent 1,1,1,2,2,3hexafluoropropane and 199 weight percent 1,1,2,3,3,3hexafluoropopane; 199 weight percent 1,1,1,2,2,3 hexafluoropropane and 199 weight percent 1,1,1,3,3,3hexafluoropropane; 199 weight percent 1,1,1,2,2,3hexafluoropropane and 199 weight percent 1,1,1,3,3 pentafluoropropane; 199 weight percent 1,1,1,2,2,3hexafluoropropane and 199 weight percent 1,1,2,2tetrafluoropropane; 199 weight percent 1,1,1,2,2,3 hexafluoropropane and 199 weight percent 1,1,1,2tetrafluoropropane; 199 weight percent 1,1,1,2,2,3hexafluoropropane and 199 weight percent 1,1,1 trifluoropropane; 199 weight percent 1,1,1,2,2,3hexafluoropropane and 199 weight percent 2,2difluoropropane; 199 weight percent 1,1,1,2,2,3hexafluoropropane and 199 weight percent 1,1difluoropropane; 199 weight percent 1,1,1,2,2,3 hexafluoropropane and 199 weight percent 2fluoropropane; 199 weight percent 1,1,1,2,2,3hexafluoropropane and 199 weight percent lfluoropropane; 199 weight percent 1,1,2,3,3,3hexafluoropopane and 199 weight percent 1,1,1,3,3,3 hexafluoropropane; 145 weight percent 1,1,2,3,3,3hexafluoropopane and 5599 weight percent 1,1,1,2,2pentafluoropropane; 165 weight percent 1,1,2,3,3,3 hexafluoropopane and 3599 weight percent 1,1,1trifluoropropane; 199 weight percent 1,1,2,3,3,3hexafluoropopane and 199 weight percent 2,2difluoropropane; 199 weight percent 1,1,2,3,3,3hexafluoropopane and 199 weight percent 1,1 difluoropropane; 187 weight percent 1,1,2,3,3,3hexafluoropopane and 1399 weight percent 2fluoropropane; 199 weight percent 1,1,2,3,3,3hexafluoropopane and 199 weight percent lfluoropropane; 7299 weight percent 1,1,1,3,3,3hexafluoropropane and 128 weight percent 1,1,2,2,3pentafluoropropane; 6099 weight percent 1,1,1,3,3,3hexafluoropropane and 140 weight percent 1,1,1,2,3pentafluoropropane; 6899 weight percent 1,1,1,3,3,3hexafluoropropane and 132 weight percent 1,2,2,3 tetrafluoropropane; 199.8 weight percent 1,1,1,3,3,3hexafluoropropane and 0.299 weight percent 1,1,2,2tetrafluoropropane; 199 weight percent 1,1,1,3,3,3 hexafluoropropane and 199 weight percent 1,1,1,2tetrafluoropropane; 199 weight percent 1,1,1,3,3,3hexafluoropropane and 199 weight percent 2,2difluoropropane; 6499 weight percent 1,1,1,3,3,3hexafluoropropane and 136 weight percent 1,2 difluoropropane; 199 weight percent 1,1,1,3,3,3hexafluoropropane and 199 weight percent 2fluoropropane; or 199 weight percent 1,1,1,3,3,3hexafluoropropane and 199 weight percent lfluoropropane.
4. A process for producing refrigeration, comprising condensing a composition of Claim 1 and thereafter evaporating said composition in the vicinity of a body to be cooled.
5. A process for producing heat comprising condensing a composition of Claim 1 in the vicinity of a body to be heated, and thereafter evaporating said composition.
6. A process for producing refrigeration, comprising condensing a composition of Claim 2 and thereafter evaporating said composition in the vicinity of a body to be cooled.
7. A process for producing heat comprising condensing a composition of Claim 2 in the vicinity of a body to be heated, and thereafter evaporating said composition.
8. A process for producing refrigeration, comprising condensing a composition of Claim 3 and thereafter evaporating said composition in the vicimty of a body to be cooled.
9. A process for producing heat comprising condensing a composition of Claim 3 in the vicinity of a body to be heated, and thereafter evaporating said composition.
10. Effective amounts of 1,1,2,2,3,3hexafluoropropane and 1,1, 1,3,3,3hexafluoropropane, 1, 1, 1,2,3pentafluoropropane, 1,1, 1,3,3 pentafluoropropane, 1,1,1,2tetrafluoropropane, 1,2,2trifluoropropane, 1,1,1 trifluoropropane, 2,2difluoropropane, 1,1difluoropropane, 2fluoropropane or (CF3)2CHCH3; 1,1,1,2,2,3hexafluoropropane and 1,1,2,3,3,3hexafluoropropane, 1,1,1,3,3,3hexafluoropropane, 1,1,1,3,3pentafluoropropane, 1,1,2,2 tetrafluoropropane, 1,1,1,2tetrafluoropropane, 1,1,1trifluoropropane, 2,2 difluoropropane, 1,1difluoropropane, 2fluoropropane or lfluoropropane; 1,1,2,3,3,3hexafluoropropane and 1,1,1,3,3,3hexafluoropropane, 1,1,1,2,2 pentafluoropropane, 1,1,1trifluoropropane, 2,2difluoropropane, 1,1 difluoropropane, 2fluoropropane or lfluoropropane; 1,1,1,3,3,3hexafluoropropane and 1,1,2,2,3pentafluoropropane, 1,1,1,2,3pentafluoropropane, 1,2,2,3 tetrafluoropropane, 1,1,2,2tetrafluoropropane, 1,1,1,2tetrafluoropropane, 2,2 difluoropropane, 1,2difluoropropane, 2fluoropropane or lfluoropropane to form binary compositions having a manximum or minium vapor pressure when compared to the vapor pressures of the components of the binary composition.
11. A process for producing refrigeration, comprising condensing a composition of Claim 10 and thereafter evaporating said composition in the vicinity of a body to be cooled.
12. A process for producing heat comprising condensing a composition of Claim 10 in the vicinity of a body to be heated, and thereafter evaporating said composition.
Description:
TITLE

REFRIGERANT COMPOSITIONS INCLUDING

HEXAFLUOROPROPANE AND A HYDROFLUOROCARBON

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of pending U.S. patent application Serial No. 08/039,563, filed March 29, 1993.

FIELD OF THE INVENTION This invention relates to compositions of mixture of hydrofluorocarbons. These compositions are useful as 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 dichlorodifluoromethane (CFC-12) 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 apphcations. 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 one or more fluorinated hydrocarbons.

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, phenohc 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 fluids 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 the discovery of refrigerant compositions of hexafluoropropane and a hydrofhiorocarbon, with the hydrofluorocarbon being hexafluoropropane, pentafluoropropane, tetrafluoropropane, trifluoropropane, difluoropropane, fluoropropane, or HFC- 356mmz. 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-hke compositions comprising effective amounts of hexafluoropropane and hexafluoropropane, pentafluoropropane, tetrafluoropropane, trifluoropropane, difluoropropane, fluoropropane, or HFC- 356mmz to form an azeotropic or azeotrope-like composition.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236ca and HFC-236fa at 25°C;

Figure 2 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236ca and HFC-245eb at 25°C; Figure 3 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236ca and HFC-245fa at 25°C;

Figure 4 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236ca and HFC-254eb at 25°C;

Figure 5 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236ca and HFC-263ca at 25°C;

Figure 6 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236ca and HFC-263fb at 25°C;

Figure 7 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236ca and HFC-272ca at 25°C; Figure 8 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236ca and HFC-272fb at 25°C;

Figure 9 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236ca and HFC-281ea at 25°C;

Figure 10 is a graph of the vapor/Uquid equiUbrium curve for mixtures of HFC-236ca and HFC-356mmz at 25°C;

Figure 11 is a graph of the vapor/Uquid equiUbrium curve for mixtures of HFC-236cb and HFC-236ea at 25°C;

Figure 12 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236cb and HFC-236fa at 25°C; Figure 13 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236cb and HFC-245fa at 25°C;

Figure 14 is a graph of the vapor/liquid equiUbrium curve for mixtures of HFC-236cb and HFC-254cb at 25°C;

Figure 15 is a graph of the vapor/Uquid equiUbrium curve for mixtures of HFC-236cb and HFC-254eb at 25°C;

Figure 16 is a graph of the vapor /liquid equilibrium curve for mixtures of HFC-236cb and HFC-263fb at 25°C;

Figure 17 is a graph of the vapor /liquid equilibrium curve for mixtures of HFC-236cb and HFC-272ca at 25°C;

Figure 18 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236cb and HFC-281ea at 25°C;

Figure 19 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236cb and HFC-281fa at 25°C;

Figure 20 is a graph of the vapor /liquid equilibrium curve for mixtures of HFC-236ea and HFC-236fa at 25°C; Figure 21 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236ea and HFC-245cb at 25°C;

Figure 22 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236ea and HFC-263fb at 25°C;

Figure 23 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236ea and HFC-272ca at 25°C;

Figure 24 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236ea and HFC-272fb at 25°C;

Figure 25 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236ea and HFC-281ea at 25°C; Figure 26 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236ea and HFC-281fa at 25°C;

Figure 27 is a graph of the vapor/liquid equiUbrium curve for mixtures of HFC-236fa and HFC-245ca at 25°C;

Figure 28 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236fa and HFC-245eb at 25°C;

Figure 29 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236fa and HFC-254ca at 25°C;

Figure 30 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236fa and HFC-254cb at 25°C; Figure 31 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236fa and HFC-254eb at 25°C;

Figure 32 is a graph of the vapor/Uquid equilibrium curve for mixtures of HFC-236fa and HFC-272ca at 25°C;

Figure 33 is a graph of the vapor/Uquid equiUbrium curve for mixtures of HFC-236fa and HFC-272ea at 25°C;

Figure 34 is a graph of the vapor/liquid equilibrium curve for mixtures of HFC-236fa and HFC-281ea at 25°C; and

Figure 35 is a graph of the vapor /liquid equilibrium curve for mixtures of HFC-236fa and HFC-281fa at 25°C.

DETAILED DESCRIPTION

The present invention relates to the following compositions:

(a) 1,1,2,2,3,3-hexafluoropropane (HFC-236ca) and 1,1,1,3,3,3- hexafluoropropane (HFC-236fa), 1,1,1,2,3-pentafluoropropane (HFC- 245eb), 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,2- tetrafluoropropane (HFC-254eb), 1,2,2-trifluoropropane (HFC-263ca), 1,1,1-trifluoropropane (HFC-263fb), 2,2-difluoroρropane (HFC-272ca), 1,1-difluoropropane (HFC-272fb), 2-fluoropropane (HFC-281ea) or (CF 3 ) 2 CHCH 3 (HFC-356mmz);

(b) 1,1,1,2,2,3-hexafluoropropane (HFC-236cb) and 1,1,2,3,3,3- hexafluoropropane (HFC-236ea), HFC-236fa, HFC-245fa, 1,1,2,2- tetrafluoropropane (HFC-254cb), HFC-254eb, HFC-263fb, HFC-272ca, HFC-272fb, HFC-281ea or 1-fluoroρropane (HFC-281fa);

(c) HFC-236ea and HFC-236fa, 1,1,1,2,2-pentafluoroproρane (HFC-245cb), HFC-263fb, HFC-272ca, HFC-272fb, HFC-281ea or HFC-281fa; or

(d) HFC-236fa and 1,1,2,2,3-pentafluoropropane (HFC-245ca), HFC-245eb, 1,2,2,3-tetrafluoropropane (HFC-254ca), HFC-254cb, HFC-254eb, HFC-

272ca, HFC-272ea, HFC-281ea or HFC-281fa.

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.

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 distiUed, 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, Uquid 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 Uquid has substantially the same composition as the Uquid from which it was evaporated or distiUed, that is, the admixture distills/refluxes without substantial composition change. It is recognized in the art that a composition is azeotrope-hke 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, torr, 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

(a) 1,1,2,2,3,3-hexafluoropropane (HFC-236ca) and 1,1,1,3,3,3- hexafluoropropane (HFC-236fa), 1,1,1,2,3-pentafluoropropane (HFC- 245eb), 1,1,1,3,3-pentafluoroρropane (HFC-245fa), 1,1,1,2- tetrafluoropropane (HFC-254eb), 1,2,2-trifluoropropane (HFC-263ca),

1,1,1-trifluoropropane (HFC-263fb), 2,2-difluoroρropane (HFC-272ca), 1,1-difluoroρroρane (HFC-272fb), 2-fluoroproρane (HFC-281ea) or (CF 3 ) 2 CHCH 3 (HFC-356mmz);

(b) 1,1,1,2,2,3-hexafluoropropane (HFC-236cb) and 1,1,2,3,3,3-

hexafluoropropane (HFC-236ea), HFC-236fa, HFC-245fa, 1,1,2,2- tetrafluoropropane (HFC-254cb), HFC-254eb, HFC-263fb, HFC-272ca, HFC-272fb, HFC-281ea or HFC-281fa;

(c) HFC-236ea and HFC-236fa, HFC-245cb, HFC-263fb, HFC-272ca, HFC- 272fb, HFC-281ea or HFC-281fa; or

(d) HFC-236fa and HFC-245ca, HFC-245eb, HFC-254ca, HFC-254cb, HFC- 254eb, HFC-272ca, HFC-272ea, HFC-281ea or HFC-281fa;

such that after 50 weight percent of an original composition is evaporated or boUed 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 boihng 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 temperature, and that, for a minimum boUing 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 ininimum 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 pressure 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 boiUng 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°C.

Components Psia Pa

HFC-236ca 24.9 172

HFC-236cb 33.6 232 HFC-236ea 29.8 206 HFC-236fa 39.4 271 HFC-245ca 14.2 98 HFC-245cb 67.4 465 HFC-245eb 16.9 117 HFC-245fa 21.6 149 HFC-254ca 13.7 95 HFC-254cb 34.2 236 HFC-254eb 34.8 240 HFC-263ca 18.2 126 HFC-263fb 54.0 372 HFC-272ca 34.5 238 HFC-272ea 20.8 143 HFC-272fb 26.5 182 HFC-281ea 47.1 325 HFC-281fa 37.7 260 HFC-356mmz 16.6 114

Substantially constant boiling, azeotropic or azeotrope-like compositions of this invention comprise the foUowing (all compositions are measured at 25°C):

COMPONENTS WEIGHT RANGES PREFERRED

(wt.%/wt/%) (wt.%/wt.%)

HFC-236ca/HFC-236fa 1-99/1-99 1-80/20-99 HFC-236ca/HFC-245eb 1-99/1-99 1-85/15-99 HFC-236ca/HFC-245fa 1-99/1-99 20-99/1-80 HFC-236ca/HFC-254eb 1-99/1-99 40-99/1-60 HFC-236ca/HFC-263ca 1-99/1-99 20-99/1-80 HFC-236ca/HFC-263fb 1-62/38-99 1-62/38-99

HFC-236ca/HFC-272ca 1-81/19-99 20-81/19-80

HFC-236ca/HFC-272fb 1-99/1-99 30-99/1-70

HFC-236ca/HFC-281ea 1-78/22-99 1-78/22-99

HFC-236ca/HFC-356mm2 : 1-99/1-99 50-99/1-50

HFC-236cb/HFC-236ea 1-99/1-99 1-99/1-99

HFC-236cb/HFC-236fa 1-99/1-99 1-99/1-99

HFC-236cb/HFC-245fa 1-99/1-99 1-60/40-99

HFC-236cb/HFC-254cb 1-99/1-99 20-99/1-80

HFC-236cb/HFC-254eb 1-99/1-99 20-99/1-80

HFC-236cb/HFC-263fb 1-99/1-99 1-99/1-99

HFC-236cb/HFC-272ca 1-99/1-99 40-99/1-60

HFC-236cb/HFC-272fb 1-99/1-99 20-99/1-80

HFC-236cb/HFC-281ea 1-99/1-99 20-99/1-80

HFC-236cb/HFC-281fa 1-99/1-99 20-99/1-80

HFC-236ea/HFC-236fa 1-99/1-99 1-99/1-99

HFC-236ea/HFC-245cb 1-45/55-99 1-45/55-99

HFC-236ea/HFC-263fb 1-65/35-99 1-65/35-99

HFC-236ea/HFC-272ca 1-99/1-99 20-99/1-80

HFC-236ea/HFC-272fb 1-99/1-99 40-99/1-60

HFC-236ea/HFC-281ea 1-87/13-99 15-87/13-85

HFC-236ea/HFC-281fa 1-99/1-99 20-99/1-80

HFC-236fa/HFC-245ca 72-99/1-28 72-99/1-28

HFC-236fa/HFC-245eb 60-99/1-40 60-99/1-40

HFC-236fa/HFC-254ca 68-99/1-32 68-99/1-32

HFC-236fa/HFC-254cb 1-99.8/0.2-99 49-99.8/0.2-60

HFC-236fa/HFC-254eb 1-99/1-99 40-99/1-60

HFC-236fa/HFC-272ca 1-99/1-99 40-99/1-60

HFC-236fa/HFC-272ea 64-99/1-36 64-99/1-36

HFC-236fa/HFC-281ea 1-99/1-99 40-99/1-60

HFC-236fa/HFC-281fa 1-99/1-99 40-99/1-60

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-Uke 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-Uke compositions continue to exist at the different pressures, but with possible different boiUng 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-boiUng 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 weU 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 the true azeotropic composition in terms of constant boiling characteristics or tendency not to segregate or fractionate on boiUng.

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 weU 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 boiUng 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 iUustrating 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 Umiting the scope of the invention.

EXAMPLE 1 Phase Study

A phase study shows the following compositions are azeotropic, all at

25°C.

Composition No. Vapor Press. psiaCkPa'.

HFC-236ca/HFC-236fa 7.6/92.4 39.5 272

HFC-236ca/HFC-245eb 9.1/90.9 16.9 117

HFC-236ca/HFC-245fa 98.3/1.7 24.9 172

HFC-236ca/HFC-254eb 77.4/22.6 21.7 150 HFC-236ca/HFC-263ca 35.4/64.6 17.8 123

HFC-236ca/HFC-263fb 13.7/86.3 54.6 376

HFC-236ca/HFC-272ca 46.8/53.2 40.2 277

HFC-236ca/HFC-272fb 56.1/43.9 29.0 200

HFC-236ca/HFC-281ea 16.3/83.7 47.4 327 HFC-236ca/HFC-356mmz 78.1/21.9 25.8 178

HFC-236cb/HFC-236ea 36.7/63.3 27.6 190

HFC-236cb/HFC-236fa 28.2/71.8 41.7 288

HFC-236cb/HFC-245fa 25.6/74.4 20.5 141

HFC-236cb/HFC-254cb 52.1/47.9 28.8 199

HFC-236cb/HFC-254eb 39.0/61.0 35.2 243

HFC-236cb/HFC-263fb 19.0/81.0 55.0 379

HFC-236cb/HFC-272ca 58.2/41.8 41.3 285

HFC-236cb/HFC-272fb 45.0/55.0 26.1 180

HFC-236cb/HFC-281ea 39.1/60.9 48.9 337

HFC-236cb/HFC-281fa 56.1/43.9 40.4 279

HFC-236ea/HFC-236fa 17.6/82.4 41.4 285

HFC-236ea/HFC-245cb 3.7/96.3 67.6 466

HFC-236ea/HFC-263fb 20.0/80.0 56.2 387

HFC-236ea/HFC-272ca 50.0/50.0 41.7 288

HFC-236ea/HFC-272fb 75.0/25.0 31.0 214

HFC-236ea/HFC-281ea 33.9/66.1 48.7 336

HFC-236ea/HFC-281fa 44.8/55.2 39.9 275

HFC-236fa/HFC-245ca 98.0/2.0 39.5 272

HFC-236fa/HFC-245eb 90.4/9.6 40.6 280

HFC-236fa/HFC-254ca 92.4/7.6 40.8 281

HFC-236fa/HFC-254cb 99.8/0.2 39.4 272

HFC-236fa/HFC-254eb 74.4/25.6 41.5 286

HFC-236fa/HFC-272ca 79.3/20.7 40.6 280

HFC-236fa/HFC-272ea 88.9/11.1 43.2 298

HFC-236fa/HFC-281ea 62.5/37.5 54.0 372

HFC-236fa/HFC-281fa 75.3/24.7 48.4 334

EXAMPLE 2

Impact of Vapor Leakage on Vapor Pressure at 25°C

A vessel is charged with an initial composition at 25°C, and the initial vapor pressure of the composition is measured. The composition is allowed to leak from the vessel, while the temperature is held constant at 25°C, until 50 weight percent of the initial composition is removed, at which time the vapor pressure of the composition remaining in the vessel is measured. The results are summarized below.

WT%A/WT%B INITIAL 50% LEAK PSIA KPA PSIA KPA DELTA %P

HFC-236ca/HFC-236fa

7.6/92.4 39.5 272 39.5 272 0.0

1/99 39.4 272 39.4 272 0.0

40/60 37.8 261 37.2 256 1.6

5 60/40 35.4 244 33.6 232 5.1

80/20 31.5 217 28.8 199 8.6

85/15 30.2 208 27.6 190 8.6

99/1 25.4 175 25.1 173 1.2

10 HFC-236ca/HFC-245eb

9.1/90.9 16.9 117 16.9 117 0.0

1/99 16.9 117 16.9 117 0.0

40/60 17.4 120 17.3 119 0.6

60/40 20. 138 19.1 132 4.5

15 85/15 22.5 155 21.4 148 4.9

99/1 24.8 171 24.8 171 0.0

HFC-236ca/HFC-245fa

98.3/1.7 24.9 172 24.9 172 0.0

20 99/1 24.9 172 24.9 172 0.0

60/40 24.4 168 24.3 168 0.4

40/60 23.7 163 23.6 163 0.4

20/80 22.8 157 22.7 157 0.4

1/99 21.7 150 21.7 150 0.0

ΔJ

HFC-236ca/HFC-254eb

77.4/22.6 21.7 150 21.7 150 0.0

90/10 23. 159 22.5 155 2.2

99/1 24.8 171 24.8 171 0.0

30 50/50 25.2 174 23.5 162 6.7

45/55 26.1 180 24.2 167 7.3

40/60 27.1 187 25.1 173 7.4

30/70 29.2 201 27.1 187 7.2

20/80 31.1 214 29.5 203 5.1

35 1/99 34.6 239 34.5 238 0.3

HFC-236ca/HFC-263ca

35.4/64.6 17.8 123 17.8 123 0.0

20/80 17.9 123 17.9 123 0.0

40 1/99 18.2 125 18.2 125 0.0

60/40 18.4 127 18.2 125 1.1

80/20 20.6 142 19.7 136 4.4

90/10 22.7 157 21.7 150 4.4

99/1 24.8 171 24.7 170 0.4

HFC-236ca/HFC-263fb

13.7/86.3 54.6 376 54.6 376 0.0

1/99 54.1 373 54.1 373 0.0

40/60 53.1 366 52. 359 2.1

5 60/40 49.8 343 45.4 313 8.8

65/35 48.5 334 42.7 294 12.

63/37 49. 338 43.8 302 10.6

62/38 49.3 340 44.4 306 9.9

10 HFC-236ca/HFC-272ca

46.8/53.2 40.2 277 40.2 277 0.0

20/80 38.8 268 37.5 259 3.4

1/99 34.9 241 34.6 239 0.9

10/90 37.2 256 35.8 247 3.8

15 70/30 39. 269 37.6 259 3.6

85/15 35.7 246 31.2 215 12.6

82/18 36.7 253 32.8 226 10.6

81/19 36.9 254 33.3 230 9.8

20 HFC-236ca/HFC-272fb

56.1/43.9 29. 200 29. 200 0.0

30/70 28.4 196 28.2 194 0.7

10/90 27.2 188 27. 186 0.7

1/99 26.5 183 26.5 183 0.0

25 80/20 28.2 194 27.9 192 1.1

99/1 25.2 174 25.1 173 0.4

HFC-236ca/HFC-281ea

16.3/83.7 47.4 327 47.4 327 0.0

30 1/99 47.2 325 47.2 325 0.0

40/60 46.8 323 46.5 321 0.6

60/40 45. 310 43.7 301 2.9

80/20 40.6 280 36.1 249 11.1

78/22 41.3 285 37.2 256 9.9

-JO

HFC-236ca/HFC-356mmz

78.1/21.9 25.8 178 25.8 178 0.0

90/10 25.6 177 25.5 176 0.4

99/1 25. 172 25. 172 0.0

40 50/50 24.9 172 24.3 168 2.4

30/70 23. 159 21.4 148 7.

20/80 21.6 149 19.5 134 9.7

18/82 21.2 146 19.2 132 9.4

10/90 19.5 134 17.8 123 8.7

45 1/99 16.9 117 16.7 115 1.2

HFC-236cb/HFC-236ea

36.7/63.3 27.6 190 27.6 190 0.0

20/80 28.3 195 28.1 194 0.7

1/99 29.9 206 29.9 206 0.0

60/40 28.7 198 28.4 196 4.5

80/20 30.9 213 30.4 210 1.6

99/1 33.5 231 33.4 230 0.3 HFC-236cb/HFC-236fa

28.2/71.8 41.7 288 41.7 288 0.0

15/85 41.3 285 41.2 284 0.2

1/99 39.6 273 39.5 272 0.3

60/40 40. 276 39.5 272 1.3 80/20 37.5 259 36.6 252 2.4

99/1 33.8 233 33.8 233 0.0

HFC-236cb/HFC-245fa

25.6/74.4 20.5 141 20.5 141 0.0 10/90 21.3 147 21.1 145 0.9

1/99 21.7 150 21.7 150 0.0

60/40 24.4 168 22.7 157 7.

65/35 25.4 175 23.5 162 7.5

70/30 26.5 183 24.4 168 7.9 80/20 28.8 199 26.9 185 6.6

99/1 33.4 230 33.2 229 0.6

HFC-236cb/HFC-254cb

52.1/47.9 28.8 199 28.8 199 0.0 80/20 30.7 212 30.3 209 1.3

99/1 33.4 230 33.4 230 0.0

20/80 31.7 219 30.9 213 2.5

1/99 34.2 236 34.2 236 0.0 HFC-236cb/HFC-254eb

39/61 35.2 243 35.2 243 0.0

20/80 35.1 242 35.1 242 0.0

1/99 34.8 240 34.8 240 0.0

70/30 34.8 240 34.8 240 0.0 90/10 34.2 236 34.1 235 0.3

99/1 33.7 232 33.7 232 0.0

HFC-236cb/HFC-263fb

19/81 55. 379 55. 379 0.0 10/90 54.8 378 54.8 378 0.0

1/99 54.1 373 54.1 373 0.0

50/50 53. 365 51.7 356 2.5

80/20 45.4 313 41.3 285 9.

82/18 44.6 308 40.4 279 9.4

84/16 43.7 301 39.5 272 9.6

85/15 43.2 298 39.1 270 9.5

99/1 34.4 237 33.9 234 1.5

HFC-236cb/HFC-272ca 58.2/41.8 41.3 285 41.3 285 0.0

80/20 40. 276 39.3 271 1.8

99/1 34.2 236 33.9 234 0.9

20/80 38.8 268 37.4 258 3.6

1/99 34.8 240 34.6 239 0.6

HFC-236cb/HFC-272fb

45/55 26.1 180 26.1 180 0.0

20/80 26.7 184 26.7 184 0.0

1/99 26.7 184 26.5 183 0.7 75/25 28.1 194 27.5 190 2.1

99/1 33.3 230 33.2 229 0.3

HFC-236cb/HFC-281ea

39.1/60.9 48.9 337 48.9 337 0.0 20/80 48.5 334 48.4 334 0.2

1/99 47.2 325 47.2 325 0.0

70/30 47.1 325 46.1 318 2.1

85/15 43.5 300 41.1 283 5.5

92/8 40.1 276 37.6 259 6.2 99/1 34.7 239 34.1 235 1.7

HFC-236cb/HFC-281fa

56.1/43.9 40.4 279 40.4 279 0.0

80/20 39.2 270 38.8 268 1. 99/1 34.1 235 34. 234 0.3

20/80 39.1 270 38.9 268 0.5

1/99 37.8 261 37.8 261 0.0

HFC-236ea/HFC-236fa 17.6/82.4 41.4 285 41.4 285 0.0

1/99 39.7 274 39.6 273 0.3

40/60 40.2 277 39.6 273 1.5

60/40 37.6 259 36.3 250 3.5

80/20 34.1 235 32.8 226 3.8 99/1 30.1 208 30.0 207 0.3 f HFC-236ea/HFC-245cb

3.7/96.3 67.6 466 67.6 466 0.0

1/99 67.5 465 67.5 465 0.0

20/80 65.9 454 64.8 447 1.7

40/60 61.1 421 56.3 388 7.9

45/55 59.5 410 53.6 370 9.9

46/54 59.2 408 53.0 365 10.5

HFC-236ea/HFC-263fb

20.0/80.0 56.2 387 56.2 387 0.0

1/99 54.3 374 54.2 374 0.2

50/50 53.7 370 51.5 355 4.1

65/35 50.2 346 45.4 313 9.6 66/34 49.9 344 44.9 310 10.0

HFC-236ea/HFC-272ca

50.0/50.0 41.7 288 41.7 288 0.0

25/75 40.6 280 39.2 270 3.4 1/99 35.0 241 34.6 239 1.1

75/25 40.0 276 38.7 267 3.2

99/1 30.6 211 30.1 208 1.6

HFC-236ea/HFC-272fb 75.0/25.0 31.0 214 31.0 214 0.0

99/1 30.0 207 29.9 206 0.3

40/60 29.9 206 29.6 204 1.0

20/80 28.5 197 28.0 193 1.8

1/99 26.6 183 26.5 183 0.4

HFC-236ea/HFC-281ea

33.9/66.1 48.7 336 48.7 336 0.0

15/85 48.2 332 48.1 332 0.2

1/99 47.2 325 47.2 325 0.0 60/40 47.5 328 46.8 323 1.5

80/20 43.7 301 40.5 279 7.3

87/13 40.8 281 36.8 254 9.8

88/12 40.3 278 36.2 250 10.2 HFC-236ea/HFC-281fa

44.8/55.2 39.9 275 39.9 275 0.0

20/80 39.2 270 39.0 269 0.5

1/99 37.8 261 37.8 261 0.0

60/40 , 39.6 273 39.4 272 0.5 80/20 37.4 258 36.4 251 2.7

99/1 30.5 210 30.2 208 1.0

HFC-236fa/HFC-245ca

98/2 39.5 272 39.5 272 0.0

99/1 39.4 272 39.4 272 0.0

60/40 32.9 227 27.4 189 16.7

70/30 35.4 244 31.5 217 11.

72/28 35.8 247 32.4 223 9.5

HFC-236fa/HFC-245eb

90.4/9.6 40.6 280 40.6 280 0.0

99/1 39.7 274 39.6 273 0.3

60/40 37.6 259 34.1 235 9.3

59/41 37.5 259 33.7 232 10.1

HFC-236fa/HFC-254ca

92.4/7.6 40.8 281 40.8 281 0.0

99/1 39.9 275 39.6 273 0.8

60/40 36.9 254 30.7 212 16.8 70/30 38.7 267 35.6 245 8.

67/33 38.3 264 34.3 236 10.4

68/32 38.4 265 34.8 240 9.4

HFC-236fa/HFC-254cb 99.8/0.2 39.4 272 39.4 272 0.0

70/30 38.8 268 38.7 267 0.3

40/60 37.3 257 37.1 256 0.5

20/80 35.9 248 35.7 246 0.6

1/99 34.3 236 34.2 236 0.3

HFC-236fa/HFC-254eb

74.4/25.6 41.5 286 41.5 286 0.0

90/10 40.9 282 40.7 281 0.5

99/1 39.6 273 39.5 272 0.3 40/60 39.7 274 39.3 271 1.

20/80 37.6 259 37. 255 1.6

1/99 34.9 241 34.9 241 0.0

HFC-236fa/HFC-272ca 79.3/20.7 40.6 280 40.6 280 0.0

90/10 40.3 278 40.3 278 0.0

99/1 39.5 272 39.5 272 0.0

40/60 38.7 267 38.2 263 1.3

20/80 36.9 254 36.3 250 1.6 1/99 34.6 239 34.6 239 0.0

HFC-236fa/HFC-272ea

88.9/11.1 43.2 298 43.2 298 0.0

99/1 40.6 280 39.8 274 2.

60/40 39.6 273 34.6 239 12.6

65/35 40.6 280 36.9 254 9.1

64/36 40.4 279 36.4 251 9.9

HFC-236fa/HFC-281ea 62.5/37.5 54. 372 54. 372 0.0

80/20 52.8 364 51.7 356 2.1

90/10 49.7 343 46.5 321 6.4

95/5 46.2 319 42.6 294 7.8

99/1 41.2 284 39.9 275 3.2 40/60 52.8 364 52.2 360 1.1

20/80 50.4 347 49.4 341 2.

10/90 48.9 337 48.2 332 1.4

1/99 47.3 326 47.2 325 0.2 HFC-236fa/HFC-281fa

75.3/24.7 48.4 334 48.4 334 0.0

90/10 46.9 323 45.6 314 2.8

99/1 40.9 282 39.9 275 2.4

40/60 45.2 312 43.3 299 4.2 20/80 41.8 288 39.9 275 4.5

10/90 39.8 274 38.6 266 3.

1/99 37.9 261 37.8 261 0.3

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°C.

EXAMPLE 3 Impact of Vapor Leakage at -25°C

A leak test is performed on compositions of HFC-236fa and HFC- 272ea, at the temperature of -25°C. The results are summarized below.

WT%A/WT%B INITIAL 50% 1 _£AK PSIA KPA PSIA KPA DELTA %P

HFC-236fa/HFC- 272ea

87.9/12.1 5.68 39.2 5.68 39.2 0.0

99/1 5.27 36.3 5.05 34.8 4.2

64/36 5.34 36.8 4.84 33.4 9.4

63/37 5.32 36.7 4.78 33.0 10.2

These results show that compositions of HFC-236fa and HFC-272ea are azeotropic or azeotrope-Uke at different temperatures, but that the weight percents of the components vary as the temperature is changed.

EXAMPLE 4

Refrigerant Performance The foUowing table shows the performance of various refrigerants. The data are based on the foUowing conditions. Evaporator temperature 48.0°F (8.9°C)

Condenser temperature 115.0°F (46.1°C) Subcooled 12.0°F (6.7°C)

Return gas 65.0°F (18.3°C)

Compressor efficiency is 75%.

The refrigeration capacity is based on a compressor with a fixed displacement of 3.5 cubic feet per minute and 75% 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. Capacity

Refrig. Press. Press. Comp. Dis. BTU/min pmp. Psia ( Pa.) Psi fkPa Temp. °F f°n £QP (kw)

CFC-11 8(55) 30(207) 167(75) 5.10 50(0.9)

HCFC-22 95(655) 258(1779) 183(84) 4.60 397(7.0)

HFC-236ca/HFC-236fa 1.0/99.0 21(145) 69(476) 129(54) 4.71 103(1.8)

7.6/92.4 21(145) 69(476) 129(54) 4.71 102(1.8)

95.0/5.0 14(97) 50(345) 134(57) 4.85 77(1.4)

HFC-236ca/HFC-245eb 1.0/99.0 9(62) 34(234) 139(59) 4.95 53(0.9)

9.1/90.9 9(62) 35(241) 138(59) 4.95 54(1.0)

95.0/5.0 14(97) 48(331) 134(57) 4.85 73(1.3)

HFC-236ca/HFC-245fa 5.0/95.0 12(83) 43(296) 137(58) 4.9 66(1.2)

98.3/1.7 14(97) 48(331) 134(57) 4.85 74(1.3)

99.0/1.0 14(97) 49(338) 134(57) 4.85 74(1.3)

HFC-236ca/HFC-254eb 5.0/95.0 20(138) 64(441) 137(58) 4.85 100(1.8)

77.4/22.6 15(103) 53(365) 135(57) 4.86 81(1.4)

95.0/5.0 14(97) 50(345) 134(57) 4.84 76(1.3)

HFC-236ca/HFC-263ca 5.0/95.0 10(69) 36(248) 143(62) 4.99 57(1.0)

35.4/64.6 11(76) 39(269) 141(61) 4.96 62(1.1)

95.0/5.0 14(97) 48(331) 135(57) 4.85 73(1.3)

HFC-236ca/HFC-263fb 5.0/95.0 31(214) 95(655) 137(58) 4.76 145(2.6)

13.7/86.3 30(207) 91(627) 137(58) 4.77 139(2.4)

95.0/5.0 15(103) 51(352) 134(57) 4.87 79(1.4)

HFC-236ca/HFC-272ca 5.0/95.0 20(138) 63(434) 142(61) 4.92 100(1.8)

46.8/53.2 18(124) 59(407) 139(59) 4.96 94(1.7)

95.0/5.0 14(97) 50(345) 135(57) 4.85 77(1.4)

HFC-236ca/HFC-272fb 5.0/95.0 15(103) 51(352) 148(64) 4.99 81(1.4)

56.1/43.9 15(103) 52(359) 141(61) 4.92 82(1.4) 95.0/5.0 14(97) 50(345) 135(57) 4.86 76(1.3)

HFC-236ca/HFC-281ea 5.0/95.0 28(193) 84(579) 147(64) 4.92 135(2.4)

16.3/83.7 27(186) 82(565) 146(63) 4.91 132(2.3) 95.0/5.0 15(103) 53(365) 135(57) 4.88 81(1.4)

HFC-236ca/HFC-356mmz 5.0/95.0 9(62) 34(234) 123(51) 4.78 50(0.9)

78.1/21.9 13(90) 45(310) 131(55) 4.83 69(1.2) 95.0/5.0 14(97) 48(331) 133(56) 4.84 73(1.3)

HFC-236cb/HFC-236ea 5.0/95.0 16(110) 56(386) 133(56) 4.81 85(1.5)

36.7/63.3 17(117) 58(400) 132(56) 4.79 88(1.5) 95.0/5.0 19(131) 63(434) 130(54) 4.74 95(1.7)

HFC-236cb/HFC-236fa 5.0/95.0 21(145) 69(476) 129(54) 4.71 103(1.8)

28.2/71.8 21(145) 67(462) 129(54) 4.71 100(1.8) 95.0/5.0 19(131) 64(441) 129(54) 4.74 95(1.7)

HFC-236cb/HFC-245fa 5.0/95.0 12(83) 43(296) 137(58) 4.9 67(1.2)

25.6/74.4 14(97) 47(324) 135(57) 4.89 73(1.3) 95.0/5.0 19(131) 62(427) 130(54) 4.74 94(1.7)

HFC-236cb/HFC-254cb 5.0/95.0 20(138) 64(441) 136(58) 4.85 99(1.7)

52.1/47.9 20(138) 64(441) 133(56) 4.8 98(1.7) 95.0/5.0 19(131) 64(441) 130(54) 4.75 96(1.7)

HFC-236cb/HFC-254eb 5.0/95.0 20(138) 65(448) 136(58) 4.85 101(1.8)

39.0/61.0 20(138) 65(448) 134(57) 4.81 100(1.8) 95.0/5.0 20(138) 64(441) 130(54) 4.75 96(1.7)

HFC-236cb/HFC-263fb 5.0/95.0 32(221) 96(662) 137(58) 4.76 146(2.6)

19.0/81.0 30(207) 93(641) 136(58) 4.76 141(2.5)

95.0/5.0 20(138) 66(455) 130(54) 4.75 99(1.7)

HFC-236cb/HFC-272ca 5.0/95.0 20(138) 63(434) 141(61) 4.93 101(1.8)

58.2/41.8 21(145) 66(455) 135(57) 4.84 102(1.8) 95.0/5.0 20(138) 64(441) 130(54) 4.75 97(1.7)

HFC-236cb/HFC-272fb 5.0/95.0 15(103) 51(352) 147(64) 5 83(1.5)

45.0/55.0 18(124) 59(407) 141(61) 4.91 92(1.6) 95.0/5.0 20(138) 64(441) 130(54) 4.76 96(1.7)

HFC-236cb/HFC-281ea 5.0/95.0 28(193) 85(586) 147(64) 4.92 136(2.4)

39.1/60.9 28(193) 84(579) 142(61) 4.87 133(2.3) 95.0/5.0 21(145) 67(462) 131(55) 4.76 102(1.8)

HFC-236cb/HFC-281fa 5.0/95.0 22(152) 70(483) 148(64) 4.94 112(2.0)

56.1/43.9 23(159) 73(503) 140(60) 4.86 114(2.0) 95.0/5.0 20(138) 66(455) 131(55) 4.76 100(1.8)

HFC-236ea/HFC-236fa 5.0/95.0 21(145) 69(476) 129(54) 4.71 102(1.8)

17.6/82.4 21(145) 67(462) 130(54) 4.74 100(1.8) 95.0/5.0 16(110) 56(386) 133(56) 4.8 85(1.5)

HFC-236ea/HFC-245cb 1.0/99.0 38(262) 111(765) 124(51) 4.55 159(2.8)

3.7/96.3 37(255) 109(752) 124(51) 4.56 157(2.8) 95.0/5.0 17(117) 58(400) 133(56) 4.82 88(1.5)

HFC-236ea/HFC-263fb 5.0/95.0 32(221) 96(662) 137(58) 4.76 146(2.6)

20.0/80.0 29(200) 91(627) 137(58) 4.78 138(2.4) 95.0/5.0 17(117) 58(400) 134(57) 4.82 89(1.6)

HFC-236ea/HFC-272ca 5.0/95.0 20(138) 63(434) 141(61) 4.93 101(1.8)

50.0/50.0 19(131) 61(421) 138(59) 4.89 97(1.7) 95.0/5.0 17(117) 57(393) 134(57) 4.82 86(1.5)

HFC-236ea/HFC-272fb 5.0/95.0 15(103) 51(352) 148(64) 4.98 82(1.4)

75.0/25.0 17(117) 56(386) 138(59) 4.87 88(1.5)

95.0/5.0 16(110) 56(386) 134(57) 4.82 86(1.5)

HFC-236ea/HFC-281ea 5.0/95.0 28(193) 85(586) 147(64) 4.91 135(2.4)

33.9/66.1 26(179) 81(558) 145(63) 4.89 128(2.3) 95.0/5.0 18(124) 59(407) 135(57) 4.84 91(1.6)

HFC-236ea/HFC-281fa 5.0/95.0 22(152) 70(483) 148(64) 4.95 112(2.0)

44.8/55.2 21(145) 69(476) 144(62) 4.91 109(1.9) 95.0/5.0 17(117) 58(400) 135(57) 4.83 89(1.6)

HFC-236fa/HFC-245ca 5.0/95.0 8(55) 30(207) 139(59) 5.0 47(0.8)

98.0/2.0 21(145) 68(469) 129(54) 4.71 101(1.8) 99.0/1.0 21(145) 69(476) 129(54) 4.71 102(1.8)

HFC-236fa/HFC-245eb

5.0/95.0 10(69) 35(241) 138(59) 4.96 55(1.0)

90.4/9.6 20(138) 65(448) 130(54) 4.75 97(1.7)

99.0/1.0 21(145) 69(476) 129(54) 4.71 103(1.8)

HFC-236fa/HFC-254ca 5.0/95.0 8(55) 29(200) 142(61) 5.05 46(0.8)

92.4/7.6 19(131) 64(441) 130(54) 4.75 96(1.7)

99.0/1.0 21(145) 69(476) 129(54) 4.71 102(1.8)

HFC-236fa/HFG 254cb

5.0/95.0 20(138) 64(441) 136(58) 4.85 100(1.8)

99.8/0.2 21(145) 69(476) 129(54) 4.71 103(1.8)

HFC-236fa/HFG 254eb 5.0/95.0 20(138) 65(448) 136(58) 4.84 101(1.8) 74.4/25.6 21(145) 69(476) 131(55) 4.75 104(1.8) 95.0/5.0 21(145) 69(476) 129(54) 4.72 103(1.8)

HFC-236fa/HFG 272ca 5.0/95.0 20(138) 64(441) 141(61) 4.92 102(1.8) 79.3/20.7 22(152) 70(483) 132(56) 4.78 106(1.9) 95.0/5.0 22(152) 70(483) 130(54) 4.73 104(1.8)

HFC-236fa/HFG 272ea 5.0/95.0 12(83) 41(283) 149(65) 5.05 67(1.2) 88.9/11.1 21(145) 67(462) 132(56) 4.76 101(1.8) 95.0/5.0 21(145) 68(469) 130(54) 4.73 102(1.8)

HFC-236fa/HFC-281ea 5.0/95.0 28(193) 85(586) 147(64) 4.92 136(2.4)

62.5/37.5 27(186) 84(579) 138(59) 4.82 130(2.3)

95.0/5.0 23(159) 73(503) 131(55) 4.73 109(1.9)

HFG236fa/HFG281fa 5.0/95.0 22(152) 70(483) 148(64) 4.95 113(2.0)

75.3/24.7 24(165) 76(524) 136(58) 4.79 116(2.0)

95.0/5.0 22(152) 72(496) 130(54) 4.73 107(1.9)

EXAMPLE 5

This Example is directed to measurements of the Uquid/vapor equilibrium curves for the mixtures in Figures 1-35.

Turning to Figure 1, the upper curve represents the composition of the Uquid, and the lower curve represents the composition of the vapor.

The data for the compositions of the Uquid in Figure 1 are obtained as foUows. A stainless steel cylinder is evacuated, and a weighed amount of HFC- 236ca is added to the cylinder. The cylinder is cooled to reduce the vapor pressure of HFC-236ca, and then a weighed amount of HFC-236fa is added to the cyUnder. The cylinder is agitated to mix the HFC-236ca and HFC-236fa, and then the cyUnder is placed in a constant temperature bath until the temperature comes to equilibrium at 25°C, at which time the vapor pressure of the HFC-236ca and HFC- 236fa in the cylinder is measured. Additional samples of liquid are measured the same way, and the results are plotted in Figure 1.

The curve which shows the composition of the vapor is calculated using an ideal gas equation of state.

Vapor/Uquid equiUbrium data are obtained in the same way for the mixtures shown in Figures 2-35.

The data in Figures 1, 3, 6-10, 12 and 15-35 show that at 25°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 earher, the higher than expected pressures of these compositions may result in an unexpected increase in the refrigeration capacity or efficiency of those compositions when compared to the pure components of the compositions.

The data in Figures 2, 4-5, 11 and 13-14 show that at 25°C, there are ranges of compositions that have vapor pressures below the vapor pressures of the pure components of the composition at that same temperature. These minimum

boiling compositions are useful in refrigeration, and may show an improved efficiency when compared to the pure components of the composition.

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.

In addition to refrigeration applications, the novel constant boiUng or substantially constant boiling compositions of the invention are also useful as aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes and power cycle working fluids.

ADDITIONAL COMPOUNDS

Other components, such as aliphatic hydrocarbons having a boiling point of -60 to + 60°C, hydrofluorocarbonalkanes having a boiling point of -60 to +60°C, hydrofluoropropanes having a boiling point of between -60 to +60°C, hydrocarbon esters having a boiUng point between -60 to +60°C, hydrochlorofluorocarbons having a boiling point between -60 to + 60°C, hydrofluorocarbons having a boiling point of -60 to +60°C, hydrochlorocarbons having a boiling point between -60 to +60°C, chlorocarbons and perfluorinated compounds, can be added to the azeotropic or azeotrope-Uke compositions described above without substantially changing the properties thereof, including the constant boUing behavior, of the compositions.

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.