WO1996015205A1

WO1996015205A1 - Compositions that include a cyclic fluorocarbon

Info

Publication number: WO1996015205A1
Application number: PCT/US1995/014426
Authority: WO
Inventors: Barbara Haviland Minor
Original assignee: E.I. Du Pont De Nemours And Company
Priority date: 1994-11-16
Filing date: 1995-11-08
Publication date: 1996-05-23

Abstract

Compositions are disclosed which include a cyclic C3FxHy (cyclic) where 1≤x≤6 and x+y=6 and CnFmH2n+2-m wherein n = 2 or 3 and 1≤m≤8; a hydrocarbon having from 1 to 5 carbon atoms; ammonia; or dimethyl ether. Examples of such compositions include perfluorocyclopropane and 1,1,1,2-tetrafluoroethane, 1,1-difluoroethane, fluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, 1,2-difluoropropane, 2-fluoropropane, 1-fluoropropane, butane, cyclopropane, dimethylether, ammonia or propane; pentafluorocyclopropane and 1,1,2-trifluoroethane, 1,1,1,2,2,3,3-heptafluoropropane, 1,1,1,3,3,3-hexafluoropropane, 1,1,1,2,2-pentafluoropropane, 1,1,1,3,3-pentafluoropropane, 1,1,2,2-tetrafluoropropane, 1,1,1-trifluoropropane, 2,2-difluoropropane, butane, dimethylether, ammonia, isobutane or propane.

Description

JΠ E

COMPOSITIONS THAT INCLUDE A CYCLIC FLUOROCARBON

FIELD OF THE INVENTION This invention relates to compositions that include a cyclic fluorocarbon.

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, paniculate 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 applications. Hydrofluorocarbons (HFCs) and fluorocarbons 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 cyclic hydrocarbon or an azeotropic or azeotrope-like composition that includes one or more cyclic fluorinated hydrocarbons. A cyclic fluorinated hydrocarbon may also be used as a cleaning agent o solvent to clean, for example, electronic circuit boards. It is desirable that the cleanin 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 cyclic fluorina 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 flui 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 pl 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 age for removing water, such as from jewelry or metal parts, as resist developers in conventional circuit manufacturing techniques including chlorine-type developing age or as strippers for photoresists when used with, for example, a chlorohydrocarbon such 1,1, 1-trichloroethane or trichloroethylene.

SUMMARY OF THE INVENTTON The present invention relates to the discovery of compositions of C3F_xH (cyclic) where l≤x≤ό and x+y =6 and CnF_mH2n+2-m wherein n = 2 or 3 and l≤m≤8; hydrocarbon having from 1 to 5 carbon atoms; ammonia; or dimethyl ether.

These compositions are useful as refrigerants, cleaning agents, expansio agents for polyolefins and polyurethanes, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, power cycle working fluids, polymerizatio media, paniculate 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 perfluorocyclopropane and at least one of 1,1,1,2-tetrafluoroethane, 1,1-difluoroethan fluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, 1,2-difluoropropane, 2-fluoropropane, fluoropropane, butane, cyclopropane, dimethylether, ammonia or propane; pentafluorocyclopropane and at least one of 1,1,2-trifluoroethane, 1,1,1,2,2,3,3- heptafluoropropane, 1,1, 1,3,3,3-hexafluoropropane, 1, 1, 1,2,2-pentafluoropropane, 1,1,1,3,3-pentafluoropropane, 1,1,2,2-tetrafluoropropane, 1,1,1-trifluoropropane, 2,2- difluoropropane, butane, dimethylether, ammonia, isobutane or propane, 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 c216 and HFC-134a at 25°C;

Figure 2 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and HFC-152a at 25°C; Figure 3 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and HFC-161 at 25°C;

Figure 4 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and HFC-227ea at 25°C;

Figure 5 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and HFC-272ea at 25°C;

Figure 6 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and HFC-281ea at 25°C;

Figure 7 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and HFC-281fa at 25°C; Figure 8 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and butane at 25°C;

Figure 9 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and cyclopropane at 25°C;

Figure 10 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and DME at 25°C;

Figure 11 is a graph of the vapor/liquid equilibrium curve for mixtures of c216 and propane at 25°C;

Figure 12 is a graph of the vapor/Uquid equilibrium curve for mixtures of c225 and HFC-143 at 25°C; Figure 13 is a graph of the vapor/liquid equilibrium curve for mixtures of c225 and HFC-227ca at 25°C;

Figure 14 is a graph of the vapor/liquid equilibrium curve for mixtures of c225 and HFC-236fa at 25°C;

Figure 15 is a graph of the vapor/liquid equilibrium curve for mixtures of c225 and HFC-245cb at 25°C;

Figure 16 is a graph of the vapor/liquid equilibrium curve for mixtures of c225 and HFC-245fa at 25°C;

Figure 17 is a graph of the vapor/liquid equilibrium curve for mixtures of c225 and HFC-254cb at 25°C; Figure 18 is a graph of the vapor/liquid equilibrium curve for mixtures of c225 and HFC-263fb at 25°C;

Figure 19 is a graph of the vapor/liquid equilibrium curve for mixtures c225 and HFC-272ca at 25°C;

Figure 20 is a graph of the vapor/liquid equilibrium curve for mixtures c225 and butane at 25°C; Figure 21 is a graph of the vapor/liquid equilibrium curve for mixtures c225 and DME at 25°C;

Figure 22 is a graph of the vapor/liquid equilibrium curve for mixtures c225 and isobutane at 25°C;

Figure 23 is a graph of the vapor/liquid equilibrium curve for mixtures c225 and propane at 25°C.

nF.TATT.Rn Π SCRTPTΓON The present invention relates to the discovery of compositions of C3F_x (cyclic) where l≤x≤6 and x+y=6 and C_nF_mH2_n+2-m wherein n = 2 or 3 and l≤m<8; hydrocarbon having from 1 to 5 carbon atoms; ammonia; or dimethyl ether. Example compounds of the formula C3F_xHy (cyclic) where l≤x≤6 and x+y =6 include perfluorocyclopropane (c216, or CCF2CF2CF2-), pentafluorocyclopropane (c225, or CCF2CF2CHF-), 1,1,2,2-tetrafluorocyclopropane, (CCF2CF2CH2-), cis-1,1,2,3- tetrafluorocyclopropane (cis-cCF2CHFCHF-) and trans-l,l,2,3-tetrafluorocyclopropa (trans-cCF2CHFCΗF-). Examples of compounds of the formula C_nF_mH2_n+2-m wherein n = 2 or 3 and l≤m≤8 include 1,1,1,2-tetrafluoroethane (HFC- 134a), 1,1,2- trifluoroethane (HFC-143), 1,1-difluoroethane (HFC-152a), fluoroethane (HFC-161), 1,1,1,2,2,3,3-heptafluoropropane (HFC-227ca), 1,1,1,2,3,3,3-heptafluoroproρane (HF 227ea), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa), 1,1,1,2,2-pentafluoropropane (H 245cb), 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,2,2-tetrafluoropropane (HFC- 254cb), 1,1,1-trifluoroρropane (HFC-263fb), 2,2-difluoropropane (HFC-272ca), 1,2- difluoropropane (HFC-272ea), 2-fluoropropane (HFC-281ea) and 1-fluoropropane (HFC-281fa). Examples of hydrocarbons having from 1 to 5 carbon atoms include propane, cyclopropane, butane and isobutane . Examples of inventive compositions include c216 and HFC- 134a, HFC-

152a, HFC-161, HFC-227ea, HFC-272ea, HFC-281ea, HFC-281fa, butane, cyclopropa DME, NH3 or propane; c225 and HFC-143, HFC-227ca, HFC-236fa, HFC-245cb, HF 245fa, HFC-254cb, HFC-263fb, HFC-272ca, butane, DME, NH3, isobutane or propan 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 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.

Hexafluorocyclopropane (C-216, cyclo-C3F6, CAS Reg. No. [931-91-9]) has been prepared by the thermal decomposition of hexafluoropropylene oxide as reported by Sargeant in Journal of Organic Chemistry, Vol.35, pages 678-682 (1970).

Pentafluorocyclopropane (C-225, cyclo-C3HF5, CAS Reg. No. [872-58-2]) has been prepared by the reaction of hexafluoropropylene oxide with trifluoroethylene as reported by Sargeant and Krespan in Journal of the American Chemical Society, Vol. 91, pages 415-419 (1969).

The present invention also relates to the discovery of azeotropic or azeotrope-like compositions of effective amounts of c216 and HFC- 134a, HFC- 152a, HFC-161, HFC-227ea, HFC-272ea, HFC-281ea, HFC-281fa, butane, cyclopropane, DME, NH₃ or propane; c225 and HFC-143, HFC-227ca, HFC-236fa, HFC-245cb, HFC- 245fa, HFC-254cb, HFC-263fb, HFC-272ca, butane, DME, NH3, isobutane or propane. 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. By "azeotrope-like" composition is meant a constant boiling, or substantially constant boiling, liquid admixture of two or more substances that beha as a single substance. One way to characterize an azeotrope-like composition is that vapor produced by partial evaporation or distillation of the liquid has substantially th same composition as the liquid from which it was evaporated or distilled, that is, the admixture distills/refluxes without substantial composition change.

It is recognized in the art that a composition is azeotrope-like if, after weight percent of the composition is removed such as by evaporation or boiling off, t difference in vapor pressure between the original composition and the composition remaining after 50 weight percent of the original composition has been removed is le 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 term well known in the art. If an azeotrope is present, there is no difference in vapor pres between the original composition and the composition remaining after 50 weight per of the original composition has been removed.

Therefore, included in this invention are compositions of effective amo of c216 and HFC-134a, HFC- 152a, HFC-161, HFC-227ea, HFC-272ea, HFC-281ea, HFC-281fa, butane, cyclopropane, DME, NH3 or propane; c225 and HFC-143, HFC- 227ca, HFC-236fa, HFC-245cb, HFC-245fa, HFC-254cb, HFC-263fb, HFC-272ca, butane, DME, NH3, isobutane or propane such that after 50 weight percent of an original composition is evaporated or boiled off to produce a remaining composition, 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, hav 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 lo 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 th 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 p components are caused by unexpected intermolecular forces between and among the molecules of the compositions, which can be a combination of repulsive and attractiv 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 maxi^' iim 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°C.

COMPONENTS c216 c225

HFC-134a

HFC-152a HFC-161

HFC-227ea

HFC-272ea

HFC-281ea

HFC-281fa butane cyclopropane

DME

NH₃ propane HFC-143

HFC-227ca

HFC-236fa

HFC-245cb

HFC-245fa HFC-254cb

HFC-263fb

HFC-272ca isobutane

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

COMPONENTS WEIGHT RANGES PREFERRED

(wt.%/wt/%) (wt.%/wt.%) c216/HFC-134a 1-99/1-99 1-80/20-99 c216/HFC-152a 1-99/1-99 40-99/1-60 C216/HFC-161 1-91/9-99 40-91/9-60 c216/HFC-227ea 1-99/1-99 40-99/1-60 c216/HFC-272ea 80-99/1-20 80-99/1-20 c216/HFC-281ea 67-99/1-33 67-99/1-33 c216/HFC-281fa 74-99/1-26 74-99/1-26 c216/butane 71-99/1-29 71-99/1-29 c216/cyclopropane 28-99/1-72 40-99/1-60 C216/DME 61-92/8-39 61-92/8-39 C2I6/NH3 69-94/6-31 69-94/6-31 c216/propane 1-86/14-99 40-86/14-60 C225/HFC-143 1-99/1-99 20-99/1-80 c225/HFC-227ca 1-99/1-99 40-99/1-60 c225/HFC-236fa 1-99/1-99 40-99/1-60 c225/HFC-245cb 1-99/1-99 1-99/1-99 c225/HFC-245fa 1-38/62-99 1-38/62-99 c225/HFC-254cb 1-99/1-99 15-99/1-85 c225/HFC-263fb 1-99/1-99 20-99/1-80 c225/HFC-272ca 1-99/1-99 60-99/1-40 c225/butane 49-99/1-51 60-99/1-40 C225/DME 1-80/20-99 20-80/20-80 c225/NH₃ 51-90/10-49 51-90/10-49 c225/isobutane 35-87/13-65 50-87/13-50 c225/propane 1-70/30-99 10-70/30-90

For purposes of this invention, "effective amount" is defined as the amo of each component of the inventive compositions which, when combined, results in th formation of an azeotropic or azeotrope-like composition. This definition includes th amounts of each component, which amounts may vary depending on the pressure app to the composition so long as the azeotropic or azeotrope-like compositions continue 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 t 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 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 the examples are merely illustrative and in no way are to be interpreted as limiting the sco of the invention.

EXAMPLE ! Phase Study

A phase study on the following compositions, wherein the composition i varied and the vapor pressures is measured, at a constant temperature of 25°C, shows that the following compositions are azeotropic (all amounts of components are weight percent).

Impact of Vapor Leakage on Vapor Pressure at 25°C

A vessel is charged with an initial liquid composition at 25°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°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.

71/29 93.6 645 85.2 587 9.0

0.0 3.2 3.4 5.5 9.2 9.5 9.8

0.0 4.9

11.4 9.9

10.9

0.0 0.0 173 2.5 0.0 0.0

0.0 3.8 16.1 8.5 9.8 3.0 5.4 6.2 6.4 4.8 0.6

0.0 0.6 0.0

3.5 5.8

4.1

The results of this Example show that these compositions are azeotropi azeotrope-like because when 50 wt.% of an original composition is removed, the vapo pressure of the remaining composition is within about 10% of the vapor pressure of th original composition, at a temperature of 25°C.

EXAMPLE 3 Impact of Vapor Leakage at 0°C

A leak test is performed on compositions c216 and DME, at the temperature of 0°C. The results are summarized below.

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 t 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 45.0°F (7.2 °C)

Condenser temperature 130.0°F (54.4°C) Liquid subcooled 15°F (83°C)

Return Gas 65T (183°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.

This Example is directed to measurements of the liquid/vapor equilibrium curves for the mixtures in Figures 1-23.

Turning to Figure 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 Figure 1 are obtained as follows. A stainless steel cylinder is evacuated, and a weighed amount of c216 is added to the cylinder. The cylinder is cooled to reduce the vapor pressure of c216, and then a weighed amount of HFC- 134a is added to the cylinder. The cylinder is agitated to mix the c216 and HFC- 134a, and then the cylinder is placed in a constant temperature bath until the temperature comes to equilibrium at 25°C, at which time the vapor pressure o the c216 and HFC- 134a 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 a ideal gas equation of state.

Vapor/liquid equilibrium data are obtained in the same way for the mixtures shown in Figures 2-23. The data in Figures 1-11, 14, 15 and 18-23 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 earlier, the higher than expected pressures of these compositions may result in an unexpected increase in the refrigeration capacity and efficiency for these compositions versus the pure components of the compositions.

The data in Figures 12, 13, 16 and 17 show that at 25°C, there are ranges of compositions that have vapor pressures lower than the vapor pressures of the pure components of the composition at that same temperature. These minimum vapor pressure 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.

The compositions of the present inventions are useful as blowing agents i the production of thermoset foams, which include polyurethane and phenolic foams, an 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 poylurethane or polyisocyanurate reaction formulation. Water may be added to the formulation raction 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. Patent 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, heat transfer media, gaseous dielectrics, and power cycle working

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 este having a boiling point between -60 to + 60°C, hydrochlorofluorocarbons having a boilin 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-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 th composition for its intended application. Preferred lubricants include esters having a molecular weight greater than 250.

Claims

CH-2414£LΔ2MS

1. A composition comprising

(a) C3F_xHy (cyclic) wherein l≤x≤6 and x+y=6 and (b) C_nF_mH2n+2-m wherein n = 2 or 3 and l≤m≤8; a hydrocarbon having from 1 to 5 carbon atoms; ammonia; or dimethyl ether

2. The composition of claim 1, comprising perfluorocyclopropane and 1,1,1,2-tetrafluoroethane, 1,1-difluoroethane, fluoroethane, 1,1,1,2,3,3,3- heptafluoropropane, 1,2-difluoropropane, 2-fluoropropane, 1-fluoropropane, butane, cyclopropane, dimethylether, ammonia or propane; pentafluorocydopropane and 1,1,2- trifluoroethane, 1, 1, 1,2,2,3,3-heptafluoropropane, 1, 1, 1,3,3,3-hexafluoropropane, 1, 1, 1,2,2-pentafluoropropane, 1, 1, 1,3,3-pentafluoropropane, 1, 1,2,2-tetrafluoropropane, 1,1,1-trifluoropropane, 2,2-difluoropropane, butane, dimethylether, ammonia, isobutane or propane.

3. Effective amounts of perfluorocyclopropane and 1,1,1,2- tetrafluoroethane, 1,1-difluoroethane, fluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, 1,2-difluoropropane, 2-fluoropropane, 1-fluoropropane, butane, cyclopropane, dimethylether, ammonia or propane; pentafluorocydopropane and 1,1,2-trifluoroethane, 1,1, 12,2,33-heptafluoropropane, 1, 1, 1,3,3,3-hexafluoropropane, 1,1, 1,2,2- pentafluoropropane, 1,1,13,3-pentafluoropropane, 1,1,2,2-tetrafluoropropane, 1,1,1- trifluoropropane, 2,2-difluoropropane, butane, dimethylether, ammonia, isobutane or propane to form an azeotropic or azeotrope-like composition.

4. The azeotropic or azeotrope-like composition of Claim 3, said composition comprising a binary composition of 1-99 weight percent perfluorocyclopropane and 1-99 weight percent 1,1,12-tetrafluoroethane; 1-99 weight percent perfluorocyclopropane and 1-99 weight percent 1,1-difluoroethane; 1-91 weight percent perfluorocyclopropane and 9-99 weight percent fluoroethane; 1-99 weight percent perfluorocyclopropane and 1-99 weight percent 1,1,1,2,3,3,3-heptafluoropropane; 80-99 weight percent perfluorocyclopropane and 1-20 weight percent 1,2- difluoropropane; 67-99 weight percent perfluorocyclopropane and 1-33 weight percent 2- fluoropropane; 74-99 weight percent perfluorocyclopropane and 1-26 weight percent 1- fluoropropane; 71-99 weight percent perfluorocyclopropane and 1-29 weight percent butane; 28-99 weight percent perfluorocyclopropane and 1-72 weight percent cyclopropane; 61-92 weight percent perfluorocyclopropane and 8-39 weight percent dimethylether; 69-94 weight percent perfluorocyclopropane and 6-31 weight percent ammonia; 1-86 weight percent perfluorocyclopropane and 14-99 weight percent propa 1-99 weight percent pentafluorocydopropane and 1-99 weight percent 1,1,2- trifluoroethane; 1-99 weight percent pentafluorocydopropane and 1-99 weight percent 1,1,1,2,2,3,3-heptafluoropropane; 1-99 weight percent pentafluorocydopropane and 1-9 weight percent 1,1,1,3,3,3-hexafluoropropane; 1-99 weight percent pentafluorocydopropane and 1-99 weight percent 1,1,1,2,2-pentafluoropropane; 1-38 weight percent pentafluorocydopropane and 62-99 weight percent 1,1,1,3,3- pentafluoropropane; 1-99 weight percent pentafluorocydopropane and 1-99 weight percent 1,1,2,2-tetrafluoropropane; 1-99 weight percent pentafluorocydopropane and 1 99 weight percent 1,1,1-trifluoropropane; 1-99 weight percent pentafluorocydopropane and 1-99 weight percent 2,2-difluoropropane; 49-99 weight percent pentafluorocydopropane and 1-51 weight percent butane; 1-80 weight percent pentafluorocydopropane and 20-99 weight percent dimethylether; 51-90 weight percen pentafluorocydopropane and 10-49 weight percent ammonia; 35-87 weight percent pentafluorocydopropane and 13-65 weight percent isobutane; or 1-70 weight percent pentafluorocydopropane and 30-99 weight percent propane.

5. Effective amounts of perfluorocyclopropane and 1,1, 1,2- tetrafluoroethane, 1,1-difluoroethane, fluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, 1,2-difluoropropane, 2-fluoropropane, 1-fluoropropane, butane, cyclopropane, dimethylether, ammonia or propane; pentafluorocydopropane and 1,1,2-trifluoroethan 1, 1, 1,2,2,3,3-heptafluoropropane, 1, 1, 1,3,3,3-hexafluoropropane, 1, 1, 1,2,2- pentafluoropropane, 1,1,1,3,3-pentafluoropropane, 1,1,2,2-tetrafluoropropane, 1,1,1- trifluoropropane, 22-difluoropropane, butane, dimethylether, ammonia, isobutane or propane to form binary compositions having a vapor pressure higher or lower than that of the components of the binary composition.

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

7. 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.

8. A process for producing refrigeration, comprising condensing a composition of Claim 3 and thereafter evaporating said composition in the vicmity of the 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. A process for producing refrigeration, comprising condensing a composition of Claim 5 and thereafter evaporating said composition in the vicinity of the body to be cooled.

11. A process for producing heat comprising condensing a composition of Claim 5 in the vicinity of a body to be heated, and thereafter evaporating said composition.

12. A process for preparing a thermset or thermoplastic foam, comprising using a composition of Claim 1 as a blowing agent.

13. A process for preparing a thermset or thermoplastic foam, comprising using a composition of Claim 3 as a blowing agent.

14. A process for preparing a thermset or thermoplastic foam, comprising using a composition of Claim 5 as a blowing agent.

15. A process for cleaning a solid surface comprising treating said surface with a composition of Claim 1.

16. A process for cleaning a solid surface comprising treating said surface with a composition of Claim 3.

17. A process for cleaning a solid surface comprising treating said surface with a composition of Claim 5.

18. A process for suppressing a fire, comprising applying to the fire a composition of Claim 1.

19. A process for suppressing a fire, comprising applying to the fire a composition of Claim 3.

20. A process for suppressing a fire, comprising applying to the fire a composition of Claim 5.