EP1047746A1 - 1,1,1,3,3-pentafluoropropane compositions - Google Patents

Abstract

The present invention relates to compositions of 1,1,1,3,3-pentafluoropropane and a hydrocarbon such as cyclohexane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2,3-dimethylpentane, 3-ethylpentane, heptane, methylcyclopentane, 2-methylpentane, 3-methylpentane, and dimethyl ether. The compositions, which may be azeotropic or azeotrope-like, may be used as refrigerants, cleaning agents, expansion agents for polyolefins and polyurethanes, active ingredients in aerosol formulations, 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.

Description

TITLE

1,1,1,3,3-PENTAFLUOROPROP.ANE COMPOSITIONS

CROSS REFERENCE TO RELATED APPLICATIONS This application claims the priority benefit of

U.S. Provisional Application 60/071,651, filed January 16, 1998.

FIELD OF THE I.NVENTION The present invention relates to compositions that include 1,1,1,3,3 -pentafluoropropane and one hydrocarbon selected from cyclohexane, 2 , 2-dimethylbutane, 2,3 -dimethylbutane, 2, 3-dimethylpentane, 3-ethylpentane, heptane, methylcyclopentane, 2-methylpentane, 3-methylpentane, or dimethyl ether. These compositions are useful as cleaning agents, expansion agents for forming polymer foams, active ingredients in aerosol formulations, 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

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 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.

Fluorinated hydrocarbons may also be useful as blowing agents in the manufacture of close-cell polyurethane, phenolic and thermoplastic foams. Insulating foams require blowing agents not only to foam the polymer, but more importantly to utilize the low vapor thermal conductivity of the blowing agents, which is an important characteristic for insulation value .

Fluorinated hydrocarbons may also be used in aerosol compositions. Aerosol compositions generally comprise an active ingredient and a propellant, wherein the propellant is a compound such as nitrogen, carbon dioxide, hydrofluorocarbons (e.g., trifluoromethane, 1, 1-difluoroethane, 1, 1, 1, 2-tetrafluoroethane) , ether (e.g., dimethyl ether), hydrocarbons (e.g., propane, butane, iso-butane) , or mixtures thereof. All such aerosol products utilize the pressure of a propellant gas or a mixture of propellant gases to expel the active ingredients from an aerosol container. For this purpose, most aerosols employ liquefied gases which vaporize and provide the pressure to propel the active ingredients when the valve on the aerosol container is opened. Such aerosol compositions containing the present azeotrope-like composition are useful as industrial products such as cleaners, and in the delivery of lubricants and mold release agents, and further in automotive products such as cleaners and polishes.

The present compositions may also find utility 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, and as carrier fluids that may be used, for example, to place a fine film of lubricant on metal parts .

Further, the present compositions may also find utility as buffing abrasive detergents to remove buffing abrasive compounds from polished surfaces such as metal, as displacement drying agents for removing surface water such as from jewelry or metal parts, as resist-developers in conventional circuit manufacturing techniques employing chlorine-type developing agents, and as strippers for photoresists when used with, for example, a chlorohydrocarbon such as 1,1,1- trichloroethane or trichloroethylene . In addition, the mixtures are useful as resist developers, where chlorine-type developers would be used, and as resist stripping agents with the addition of appropriate halocarbons .

SUMMARY OF THE INVENTION

The present invention relates to the discovery of compositions of 1, 1, 1, 3 , 3-pentafluoropropane and a hydrocarbon such as cyclohexane, 2, 2 -dimethylbutane, 2, 3 -dimethylbutane, 2, 3-dimethylpentane,

3-ethylpentane, heptane, methylcyclopentane, 2-methylpentane, 3 -methylpentane and dimethylether . These compositions are useful as refrigerants, expansion agents for polyolefins and polyurethanes, cleaning agents, active ingredients in aerosol formulations, 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 1, 1, 1, 3, 3 -pentafluoropropane and a hydrocarbon selected from cyclohexane, 2, 2-dimethylbutane, 2, 3 -dimethylbutane, 2, 3-dimethylpentane, 3-ethylpentane, heptane, methylcyclopentane, 2-methylpentane, 3 -methylpentane and dimethylether to form an azeotropic or azeotrope-like composition. DETAILED DESCRIPTION

The present invention related to the discovery of compositions of 1, 1, 1, 3 , 3-pentafluoropropane (HFC- 245fa, CF₃CH₂CHF₂, normal boiling point of 15°C) and a hydrocarbon such as cyclohexane (cyclo- (CH₂) ₆, normal boiling point of 81°C) , 2 , 2-dimethylbutane (CH₃C(CH₃)₂CH₂CH₃, normal boiling point of 50°C) , 2, 3 -dimethylbutane (CH₃CH(CH₃) CH (CH₃) CH₃, normal boiling point of 58°C) , 2 , 3-dimethylpentane (CH₃CH(CH₃)CH(CH₃)CH₂CH₃, normal boiling point of 90°C) , 3-ethylpentane (CH₃CH(CH₂CH₃) CH₂CH₂CH₃, normal boiling point of 93°C) , heptane (CH₃ (CH₂) ₅CH₃, normal boiling point of 98°C) , methylcyclopentane (cyclo- (CH₃) CHCH₂CH₂CH₂CH₂-, normal boiling point of 72°C) , 2-methylpentane (CH₃CH (CH₃) CH₂CH₂CH₃, normal boiling point of 60°C) , 3 -methylpentane (CH₃CH₂CH (CH₃) CH₂CH₃, normal boiling point of 63°C) ; or dimethylether (CH₃OCH₃, normal boiling point of -25°C) .

1-99 wt.% of each of the components of the compositions can be used as refrigerants, expansion agents for polyolefins and polyurethanes, cleaning agents, 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 present invention also relates to the discovery that effective amounts of each of the above mixtures form azeotropic or azeotrope-like compositions .

By an 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 an 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.

Herein, 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, torr, dynes per square centimeter, millimeters of mercury, inches of water and other equivalent units 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

1, 1, 1, 3 , 3-pentafluoropropane and cyclohexane,

2, 2 -dimethylbutane, 2, 3 -dimethylbutane,

2 , 3 -dimethylpentane , 3 -ethylpentane, heptane, methylcyclopentane, 2-methylpentane, 3 -methylpentane, or dimethylether such that after 50 weight percent of an original composition is evaporated or boiled of to produce a remaining compositions, 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 temperature, 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 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 boiling may exhibit unexpected increases in the capacity or efficiency versus the components of the refrigerant composition.

The vapor pressure of the components at 25°C are:

Components Psia kPa

HFC-245fa 21.4 147 cyclohexane 1.89 13.0

2 , 2 -dimethylbutane 6.17 42.5

2 , 3 -dimethylbutane 4.81 33.2

2 , 3 -dimethylpentane 1.33 9.17

3 -ethylpentane 1.12 7.72 heptane 0.88 6.07 methylcyclopentane 2.66 18.3

2 -methylpentane 3.67 25.3

3 -methylpentane 4.09 28.2 dimethylether 85.7 591

Substantially constant boiling, azeotropic or azeotrope-like compositions of this invention comprise the following (all compositions are measured at 25°C) : COMPON.ENTS WEIGHT RANGES PREFERRED

(wt%/wt%) ( t%/wt%)

HFC-245fa/cyclohexane 78-99/1-22 85-99/1-15 HFC-245fa/2, 2-dimethylbutane 65-99/l-₃5 85-99/1-15

HFC-245fa/2, ₃ -dimethylbutane 68-99/1-32 85-99/1-15

HFC-245fa/2, 3 -dimethylpentane 76-99/1-24 85-99/1-15

HFC-245fa/₃ -ethylpentane 77-99/1-23 85-99/1-15

HFC-245fa/heptane 77-99/l-2₃ 85-99/1-15 HFC-245fa/methylcyclopentane 75-99/1-25 85-99/1-15

HFC-245fa/2-methylpentane 70-99/1-30 85-99/1-15

HFC-245fa/3 -methylpentane 72-99/1-28 85-99/1-15

HFC-245fa/dimethylether 92-99/1-8 92-99/1-8

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 the 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.

E.XAMPLES

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. E.XAMPLE 1 Phase Study

A phase study was made on the mixtures below wherein compositions were varied and the vapor pressure measured at a constant temperature of 25°C. An azeotropic composition is obtained as evidenced by the maximum vapor pressure, higher than the pressure of either pure compound, observed and indentified below.

Composition No. Vapor Pressure

Wt%/Wt% Psia (kPa) HFC-245fa/2 , 2-dimethylbutane 92.5/7.5 22.0 152 HFC-245fa/2 , 3-dimethylbutane 96.6/3.4 21.6 149 HFC-245fa/2-methylpentane 98.8/1.2 21.5 148

EX2\MPLE 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, 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/W %B INITI-AL 50% LEAK

PSIA KPA PSIA KPA DELTA %P

HFC-245fa/cyclohexane

99/1 21.3 147 21.2 146 0.5

90/10 19.8 137 19.0 131 4.0

80/20 18.7 129 17.1 118 8.6

78/22 18.5 128 16.7 115 9.7 HFC-245f a/2, 2 -dimethylbutane

92.5/7.5 22.0 152 22.0 152 0.0

99/1 21.6 149 21.6 149 0.0

80/20 21.6 149 21.2 146 1.9

70/30 21.1 145 19.9 137 5.7

65/35 20.8 143 18.8 130 9.6

HFC- 245 fa/2, 3 -dimethylbutane 96.6/3.4 21.6 149 21.6 149 0.0

99/1 21.5 148 21.5 148 0.0

80/20 20.8 143 20.1 139 3.4

70/30 20.1 139 18.4 127 8.5

68/32 20.0 138 18.0 124 10.0

HFC-245f a/2, 3 -dimethylpentane

99/1 21.3 147 21.2 146 0.5

90/10 20.1 139 19.4 137 3.5

80/20 19.2 132 17.9 123 6.8 76/24 18.9 130 17.1 118 9.5

HFC-245fa/3-ethylpentane

99/1 21.3 147 21.2 146 0.5

90/10 20.0 138 19.2 132 4.0

80/20 19.1 132 17.7 122 7.3

77/23 18.9 130 17.1 118 9.5

HFC-245fa/heptane

99/1 21.2 146 21.1 145 0.5

90/10 19.9 137 19.1 132 4.0

80/20 19.0 131 17.4 120 8.4

77/23 18.7 129 16.9 117 9.6

HFC-245fa/methylcyclopentane 99/1 21.3 147 21.3 147 0.0

90/10 20.2 139 19.6 135 3.0

80/20 19.2 132 17.9 123 6.8

75/25 18.8 130 17.0 117 9.6 HFC-245fa/2--methylpentane

98.8/1.2 21.5 148 21.5 148 0.0

99/1 21.5 148 21.5 148 0.0

90/10 21.0 145 20.8 143 1.0

80/20 20.3 140 19.5 134 3.9

70/30 19.6 135 17.7 122 9.7

HFC-245fa/3- ■methylpentane

99/1 21.4 147 21.4 147 0.0

90/10 20.8 143 20.5 141 1.4

80/20 20.1 139 19.1 132 5.0

72/28 19.5 134 17.6 121 9.7

HFC-245fa/DME 99/1 21.9 151 21.7 150 0.9 95/5 24.1 166 22.8 157 5.4 92/8 26.2 181 23.7 163 9.5

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.

E.XJ.MPLE 3 Impact of Vapor Leakage at 0°C

A leak test is performed on compositions of

HFC-245fa and 2, 2-dimethylbutane, at a temperature of 0°C. The results are summarized below. WT%A/ T%B INITIAL 50% L.EAK

PSIA KPA PSIA KPA DELTA %P

HFC-245f a/2, 2 -dimethylbutane 91.7/8.3 7.85 54.1 7.85 54.1 0.0

99/1 7.66 52.8 7.63 52.6 0.4

80/20 7.73 53.3 7.60 52.4 1.7

70/30 7.56 52.1 7.17 49.4 5.2

64/36 7.45 51.4 6.73 46.4 9.7

These results show that compositions of HFC- 245fa and 2, 2 -dimethylbutane are azeotropic or azeotrope-like at different temperatures, but that the weight percents of the components vary as the temperature is changed.

E.XAMPLE 4 The following table shows the performance of various refrigerants . The data are based on the following conditions.

Evaporator temperature 45°F (7.0°C)

Condenser temperature 130°F (54.0°C)

Return gas temperature 65°F (18.0°C) Subcooled 15°F (8.3°C)

Compressor efficiency is 75%

Evap. Cond. Capacity

Press . Press . Comp . Dis . Btu/min Psia kPa Psia kPa Temp F C COP and kW

HFC - 245 fa/ cyclohexane

1/99 0.9 6.2 6.3 43 147.0 63.9 3.84 6.0 0.11

99/1 10.3 71 54.0 372 158.0 70.0 3.65 56.0 0.99

HFC-245f a/2, 2 -dimethylbutane

1/99 3.0 21 16.8 116 133.4 56.3 3.64 16.9 0.30

99/1 11.5 79 56.6 390 155.0 68.3 3.70 60.6 1.07 HFC-245fa/2, 3-dimethylbutane 1/99 2.2 15 13.0 90 138.3 59.1 3.74 13.0 0.23

99/1 11.3 77 56.0 386 155.5 68.6 3.70 59.8 1.05

HFC-245fa/2,3-dimethylpentane

1/99 0.6 4.1 4.8 33 136.7 58.2 3.80 4.3 0.08

99/1 10.4 72 53.9 372 157.7 69.8 3.66 56.1 0.98

HFC-245fa/3-ethylpentane 1/99 0.5 3.4 4.2 29 137.9 58.8 3.82 3.7 0.06

99/1 10.0 69 53.3 367 158.7 70.4 3.64 54.7 0.96

HFC-245fa/heptane

1/99 0.4 2.8 3.5 24 139.3 59.6 3.86 3.0 0.05 99/1 9.6 66 52.5 362 160.2 71.2 3.60 52.8 0.93

HFC-245fa/methylcyclopentane 1/99 1.2 8.3 8.4 58 145.4 63.0 3.80 8.2 0.14

99/1 10.7 74 54.7 377 156.9 69.3 3.68 57.6 1.01

HFC-245fa/2-methylpentane

1/99 1.9 13 12.2 84 139.4 59.7 3.72 11.9 0.21

99/1 11.2 77 55.8 385 155.6 68.7 3.70 59.6 1.05

HFC-245fa/3-methylpentane

1/99 1.7 12 11.1 77 0.2 60.1 3.73 10.7 0.19

99/1 11.1 77 55.6 383 5.8 68.8 3.70 59.2 1.04

HFC-245fa/dimethylether 1/99 48.1 332 181.01248 193.1 89.5 3.68 213.1 3.75

99/1 10.4 72 53.9 372 157.7 69.8 3.66 56.1 0.99

.ADDITION.AL COMPOUNDS Other components, such as aliphatic hydrocarbons having a boiling point of about -60 to

100°C, hydrofluorocarbon alkanes having a boiling point of about -60 to 100°C, hydrofluoropropanes having a boiling point of between about -60 to 100°C, hydrocarbon esters having a boiling point between about -60 to 100°C, hydrochlorofluorocarbons having a boiling point between about -60 to 100°C, hydrofluorocarbons having a boiling point of about -60 to 100°C, hydrochlorocarbons having a boiling point between about -60 to 100°C, chlorocarbons and perfluorinated compounds, can be added in small amounts to the azeotropic or azeotrope-like compositions described above without substantially changing the properties thereof, including the constant boiling 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 provide 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.

Claims

WHAT IS CLAIMED IS;

1. A composition comprising effective amounts of 1, 1, 1, 3 , 3-pentafluoropropane and an at least one hydrocarbon selected from the group consisting of cyclohexane, 2, 2-dimethylbutane, 2, 3 -dimethylbutane, 2, 3 -dimethylpentane, 3 -ethylpentane, heptane, methylcyclopentane ,

2-methylpentane, 3 -methylpentane and dimethylether to form an azeotropic or azeotrope-like composition.

2. The azeotropic or azeotrope-like composition of claim 1, said composition comprising: 78-99 weight percent 1, 1, 1, 3 , 3-pentafluoropropane and 1-22 weight percent cyclohexane; 65-99 weight percent 1, 1, 1, 3 , 3-pentafluoropropane and 1-35 weight percent 2, 2-dimethylbutane; 68-99 weight percent 1,1,1,3,3- pentafluoropropane and 1-32 weight percent 2,3- dimethylbutane ; 76-99 weight percent 1,1,1,3,3- pentafluoropropane and 1-24 weight percent 2,3- dimethylpentane ; 77-99 weight percent 1,1,1,3,3- pentafluoropropane and 1-23 weight percent 3- ethylpentane ; 77-99 weight percent 1,1,1,3,3- pentafluoropropane and 1-23 weight percent heptane; 75- 99 weight percent 1, 1, 1, 3 , 3-pentafluoropropane and 1-25 weight percent methylcyclopentane; 70-99 weight percent 1, 1, 1, 3, 3 -pentafluoropropane and 1-30 weight percent 2- methylpentane; 72-99 weight percent 1,1,1,3,3- pentafluoropropane and 1-28 weight percent 3- methylpentane; and 92-99 weight percent 1,1,1,3,3- pentafluoropropane and 1-8 weight percent dimethyl ether.

3. A process for producing refrigeration, comprising condensing a composition of Claim 1 or 2, and thereafter evaporating said composition in the vicinity of the body to be cooled.

4. A process for producing heat comprising, comprising condensing a composition of Claim 1 or 2 in the vicinity of the body to be heated, and thereafter evaporating said composition.

5. A process for cleaning a solid surface which comprises contacting said surface with a composition of Claim 1 or 2.

6. An aerosol composition comprising active ingredient and propellant, wherein the active ingredient is a composition of Claim 1 or 2.

7. A process for preparing a thermoset or thermoplastic foam, comprising using a composition of Claim 1 or 2 as a blowing agent .