Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K3/00—Materials not provided for elsewhere
  • C09K3/30—Materials not provided for elsewhere for aerosols
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
  • C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
  • C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
  • C08J9/14—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent organic
  • C08J9/143—Halogen containing compounds
  • C08J9/144—Halogen containing compounds containing carbon, halogen and hydrogen only
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K5/00—Heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants; Materials for the production of heat or cold by chemical reactions other than by combustion
  • C09K5/02—Materials undergoing a change of physical state when used
  • C09K5/04—Materials undergoing a change of physical state when used the change of state being from liquid to vapour or vice versa
  • C09K5/041—Materials undergoing a change of physical state when used the change of state being from liquid to vapour or vice versa for compression-type refrigeration systems
  • C09K5/044—Materials undergoing a change of physical state when used the change of state being from liquid to vapour or vice versa for compression-type refrigeration systems comprising halogenated compounds
  • C09K5/045—Materials undergoing a change of physical state when used the change of state being from liquid to vapour or vice versa for compression-type refrigeration systems comprising halogenated compounds containing only fluorine as halogen
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2207/00—Foams characterised by their intended use
  • C08J2207/04—Aerosol, e.g. polyurethane foam spray
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K2205/00—Aspects relating to compounds used in compression type refrigeration systems
  • C09K2205/22—All components of a mixture being fluoro compounds
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K2205/00—Aspects relating to compounds used in compression type refrigeration systems
  • C09K2205/32—The mixture being azeotropic

Definitions

• the present invention relates to azeotrope-like compositions of 1,1,1,2,3,3,3-heptafluoropropane and 1,1-difluoroethane. These mixtures have no effect on stratospheric ozone and are useful as refrigerants for heating and cooling applications. These mixtures may also be employed as aerosol propellants, heat transfer media, fire suppression agents, gaseous dielectrics or blowing agents for plastic foams.
• CFCs chlorofluorocarbons
• azeotropic mixtures as refrigerants is known in the art, and is discussed for example in R.C. Downing, "Fluorocarbon Refrigerants Handbook,” Prentice-Hall, 1988 and R.J. Dossat, "Principles of Refrigeration,” 2nd edition, Wiley, 1981.
• Azeotropic or azeotrope-like compositions do not fractionate upon boiling or evaporation. This behavior is desirable when employing vapor compression equipment for refrigeration, since no fractionation will occur upon evaporation and condensation. Such fractionation can result in undesirable refrigerant distribution and also adversely affect the cooling or heating ability of the system.
• Non-azeotropic refrigerant mixtures are known in the art, see, e.g., U.S. Patent 4,303,536, but have not found widespread use. Since the NARMs fractionate during the refrigeration cycle, their use may require certain equipment changes.
• hydrofluorocarbons such as 1, 1,1,2,3,3,3-heptafluoropropane (HFC227ea) and 1,1-difluoroethane (HFC152a) have no effect on stratospheric ozone, i.e., their ozone depletion potential (ODP) is zero.
• HFC227ea 1, 1,1,2,3,3,3-heptafluoropropane
• HFC152a 1,1-difluoroethane
• chloro luorocarbons as blowing agents is well known in the art, but these materials are to be ultimately banned due to their role in the destruction of stratospheric ozone.
• hydrochlorofluorocarbons for example 2,2-dichloro-l,1,1-trifluoroethane (CF_CHC1 2 )
• HCFCs hydrochlorofluorocarbons
• CF_CHC1 2 2,2-dichloro-l,1,1-trifluoroethane
• CFCs chlorofluorocarbons
• Another object of the invention is to provide novel environmentally acceptable refrigerants which are useful in cooling and heating applications.
• a further object of the invention is to provide environmentally acceptable, non-toxic, nonflammable aerosol propellants and foam blowing agents.
• the azeotrope-like compositions comprise from about 55 to about 95 weight percent 1,1, 1,2,3,3,3-he ⁇ tafluoropropane and from about 5 to about 45 weight percent 1,1-difluoroethane. These compositions have a boiling point of about -19.0°C at 1 atm. These compositions are azeotrope-like because the composition of said mixtures does not substantially change upon evaporation or condensation.
• such azeotrope-like compositions comprise from about 60 to about 90 weight percent 1,1,1,2,3,3,3-heptafluoropropane and from about 10 to about 40 weight percent 1,1-difluoroethane.
• the compound 1,1,1,2,3,3,3-heptafluoropropane is known in the art and has been shown to be an efficient fire suppression agent, see, e.g., M. Robin, "Large Scale Testing of Halon Alternatives," 1991 International CFC and Halon Alternatives Conference, Baltimore, MD, December 3-5, 1991.
• non-flammable azeotrope-like mixtures are readily obtained by combining 1,1,1,2,3,3,3-heptafluoropropane with 1, 1-difluoroethane.
• azeotrope-like is used herein for mixtures of the invention because in the claimed proportions the compositions of 1,1,1,2,3,3,3-heptafluoropropane and 1,1-difluoroethane are constant boiling or essentially constant boiling. Furthermore, no or essentially no fractionation occurs upon evaporating or condensing the mixtures.
• One method for determining whether a candidate mixture is azeotrope-like is to determine whether the boiling point versus composition curve passes through an extremum, see, e.g., W. Swietoslawski, "Azeotropy and Polyazeotropy, " Pergamon, 1963, and J.M. Smith and H.C. Van Ness, "Introduction to Chemical Engineering Thermodynamics,” McGraw-Hill, 1987.
• a candidate mixture is azeotrope-like by determining whether the vapor pressure versus composition curve passes through an extremum, see, e.g., M. McLinden and G. Morrison, NBS Technical Note 1226, National Bureau of Standards, p. 96, 1986, Smith and Van Ness, op. cit.. and U.S. Patent 4,978,467.
• Azeotrope-like mixtures which possess a maximum in the vapor pressure versus composition curve will exhibit a minimum in the boiling point versus composition curve.
• an azeotrope-like mixture One of the characteristics of an azeotrope-like mixture is that there is a range of compositions containing the same components in varying proportions which are azeotrope-like. It is well known to those skilled in the art that an azeotrope of two compounds represents a unique interaction but with a variable composition depending on the temperature and/or pressure. For example, to those skilled in the art it is understood that the boiling point and composition of an azeotrope will vary with pressure.
• Another way to define an azeotrope-like mixture within the meaning of this invention is to state that such mixtures exhibit vapor pressures within about +/- 5 psia (35 kPa) at 70°F (21°C) of the most preferred compositions disclosed herein (about 65 psia at 70°F (21°C)).
• azeotrope-like mixture within the meaning of this invention is that given by Bivens (Fluorocarbon Mixtures as CFC Alternatives, 200th ACS National Meeting, Washington, DC, August 18, 1990).
• “near-azeotropes” are those mixtures for which the dew point/bubble point delta T is less than or equal to 5°C. It is to be understood that the terms “near azeotropes” and “azeotrope-like mixtures” are interchangeable in describing such systems.
• the mixtures of the present invention are azeotrope-like because for all compositions, the bubble point/dew point delta T is less than 5°C.
• the inventive compositions are useful in a variety of applications.
• the azeotrope-like compositions of the invention may be used, in the presence of a suitable lubricant if required, in a method for producing refrigeration which comprises condensing a refrigerant comprising the azeotropic-like compositions and thereafter evaporating the refrigerant in the vicinity of the body to be cooled.
• the azeotrope-like compositions of the invention may be used, in the presence of a suitable lubricant if required, in a method for producing heating which utilizes condensing a refrigerant comprising the azeotropic-like compositions in the vicinity of the body to be heated, and thereafter evaporating the refrigerant.
• a suitable lubricant if required, in a method for producing heating which utilizes condensing a refrigerant comprising the azeotropic-like compositions in the vicinity of the body to be heated, and thereafter evaporating the refrigerant.
• the azeotrope-like compositions of the invention are also useful in foam blowing and aerosol propellant applications.
• compositions may include additional, non-interfering components so as to form new azeotrope-like compositions. Any such compositions are considered to be within the scope of the present invention.
• the present invention is more fully illustrated by the following examples, which are to be understood as exemplary only, and non-limi ing.
• EXAMPLE 1 This example demonstrates the inertion of HFC-152a by HFC-227ea.
• concentration of HFC-227ea required to inert HFC-152a was measured in an 8.0 L explosion sphere, consisting of two 304 stainless hemispheres welded on stainless steel flanges, and equipped with instrumentation allowing the monitoring of pressure and temperature as a function of time.
• a mixture of HFC-152a and air and the desired concentration of the inerting agent HFC-227ea were introduced into the sphere employing partial pressures to determine the volumes of agent, fuel and air. The mixture was then subjected to a DC spark of 70 J ignition energy, located in the center of the sphere.
• HFC-227ea A straight line drawn from the origin and not crossing into the flammable region gives the minimum ratio of HFC-227ea to HFC-152a required to provide a nonflammable mixture. It is found that mixtures of HFC-227ea and HFC-152a may contain up to approximately 25 weight percent of HFC-152a and remain nonflammable.
• EXAMPLE 2 This example demonstrates the azeotrope-like nature of HFC-227ea/HFC-152a mixtures. Vapor pressure data for 80:20 and 30:70 by weight mixtures of HFC-227ea and HFC-152a are shown in Tables 1 and 2. TABLE 1: VAPOR PRESSURE OF A 80:20 BY WEIGHT MIXTURE OF HFC-227ea AND HFC-152a
• the CSD binary interaction coefficient allows the calculation of accurate physical and thermodynamic properties for mixtures of fluorinated compounds such as HFC-152a and HFC-227ea.
• the CSD equation of state accurately describes the physical and thermodynamic properties of fluorocarbons, and their mixtures, and also accurately represents the zeotropic or azeotropic nature of such mixtures.
• the binary interaction coefficient was determined following the procedure described by Morrison and McLinden in NBS Technical Note 1226. The binary interaction coefficient was found to be -0.014, and to be independent of the composition of the mixture.
• phase (Pxy) diagram for tl»e system HFC-227ea/HFC-152a is shown in FIG. 2; in this figure the upper line is the bubble line (saturated liquid), and the lower line is the dew line (saturated vapor). It is seen from FIG. 2 that the dew point-bubble point delta T is less than 5°C for all compositions. Hence, mixtures of
• HFC-227ea and HFC-152a are seen to be azeotrope-like over the entire composition range.
• an 80:20 by weight mixture of HFC-227ea and HFC-152a is seen from FIG. 2 to be characterized by a bubble point/dew point delta T of 0.7°C.
• This example demonstrates the nonflammability of the mixtures.
• the 80:20 by weight mixture of HFC-227ea and HFC-152a described in Example 2 was tested for flammability in the following fashion.
• the sample cylinder was placed on a concrete pad and the valve to the cylinder opened slightly to allow the escape of the sample.
• the leaking vapor stream could not be ignited with a flame source held approximately 0.5 to 3.0 inches from the location of the leak.
• a similar test with pure HFC-152a resulted in the ignition of the leaking HFC-152a gas stream to produce a self-propagating flame; the gas stream continued to burn on its own after removal of the flame source.
• EXAMPLE 4 The foregoing formulations of Examples 1 and 2 are used as propellants, heat transfer media, fire suppression agents, gaseous dielectrics and as blowing agents in conventional fashion, and suitable results are obtained.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Dispersion Chemistry (AREA)
• Polymers & Plastics (AREA)
• Medicinal Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Physics & Mathematics (AREA)
• Combustion & Propulsion (AREA)
• Thermal Sciences (AREA)
• Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
• Detergent Compositions (AREA)
• Fire-Extinguishing Compositions (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

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• 1994
  • 1994-03-17 ZA ZA941898A patent/ZA941898B/xx unknown
  • 1994-03-18 BR BR9406176A patent/BR9406176A/pt not_active Application Discontinuation
  • 1994-03-18 CA CA002157781A patent/CA2157781A1/en not_active Abandoned
  • 1994-03-18 WO PCT/US1994/002940 patent/WO1994021745A1/en not_active Application Discontinuation
  • 1994-03-18 EP EP94911644A patent/EP0689572A1/en not_active Withdrawn
  • 1994-03-18 TW TW083102426A patent/TW293035B/zh active
  • 1994-03-18 JP JP6521256A patent/JPH08508253A/ja active Pending
  • 1994-03-18 AU AU64117/94A patent/AU6411794A/en not_active Abandoned
• 1995
  • 1995-09-18 NO NO953675A patent/NO953675L/no unknown
  • 1995-09-18 FI FI954401A patent/FI954401A/fi not_active Application Discontinuation

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