FLUORINATED DIESTER COMPOUNDS AND THEIR USE IN HEAT TRANSFER SYSTEM

Abstract

A compound of formula (I): wherein W is independently selected from the group consisting of H, F, CI, Br, and I; X is independently selected from the group consisting of H, F, CI, Br, and I; Y is independently selected from the group consisting of F, CI, Br, and I; Z is independently selected from the group consisting of H, F, CI, Br, and I; n is an integer from 1 to 8; and n′ is an integer from 1 to 12.

##STR00001##

Claims

1. A compound of formula (I): ##STR00015## wherein W is independently selected from the group consisting of H, F, Cl, Br, and I; X is independently selected from the group consisting of H, F, Cl, Br, and I; Y is independently selected from the group consisting of F, Cl, Br, and I; Z is independently selected from the group consisting of H, F, Cl, Br, and I; n is an integer from 1 to 8; and n′ is an integer from 1 to 12.

2. A compound according to claim 1, wherein W is H or F, and preferably H.

3. A compound according to claim 1 or 2 wherein X is H or F, preferably H.

4. A compound according to any one of the preceding claims wherein W is H; X is H; Y is independently selected from the group consisting of F, Cl and I; and Z is independently selected from the group consisting of H, F, Cl and I.

5. A compound according to any one of the preceding claims wherein Y is F.

6. A compound according to any one of the preceding claims wherein Z is H or F.

7. A compound according to any one of the preceding claims wherein n is an integer from 1 to 5.

8. A compound according to any one of the preceding claims wherein n′ is an integer from 1 to 10.

9. A compound according to claim 1 wherein the compound of formula (I) is a compound of formula (II): ##STR00016##

10. A compound according to claim 1 wherein the compound of formula (I) is a compound of formula (III) ##STR00017##

11. A compound according to claim 1 wherein the compound of formula (I) is a compound of formula (IV) ##STR00018##

12. A composition comprising at least two different compounds of formula (I) as described in any of claims 1 to 11, for example wherein at least one compound of formula (I) is a compound of formula (V) and at least one compound of formula (I) is a compound of formula (VI) ##STR00019##

13. A composition comprising a heat transfer fluid, together with one or more compounds as defined in any one of claims 1 to 11 and/or a composition as defined in claim 12.

14. A composition according to claim 13 wherein the heat transfer fluid comprises one or more compounds selected from the group of (hydro)fluoroolefins (HFOs), hydrofluorocarbons (HFCs), chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrocarbons.

15. A composition according to claim 13 wherein the heat transfer fluid comprises one or more compounds selected from the group of R-1234ze, R-1234yf, R-1233xf, R-1233zd, R-1243zf, R-134a, R-152a, R-32, R-161, R-125, R-134, propane, propylene, carbon dioxide, R-245fa, R-236fa, R-227ea, R-143a, n-butane, iso-butane and R-365mfc.

16. A composition according to claim 15 wherein the heat transfer fluid comprises one or more compounds selected from the group of R-1234ze, R-1234yf, R-1233xf, R-1233zd, R-1243zf, R-134a, R-152a and R-32.

17. A composition according to claim 16 wherein the heat transfer fluid comprises R-1234ze.

18. A composition according to claim 16 wherein the heat transfer fluid comprises R-1234yf.

19. A composition according to any one of claims 13 to 18, which is less flammable than a composition comprising the same heat transfer fluid combined with a polyalkylene glycol (PAG) and/or polyol ester (POE) based lubricant.

20. A composition according to any one of claims 13 to 18, which is less flammable than the heat transfer fluid alone.

21. A composition according to any one of claims 13 to 18, which has an ignition temperature of about 500° C. or greater, preferably about 600° C. or greater.

22. A composition according to any one of claims 13 to 20, which is non-flammable.

23. A composition according to claims 13 to 22 further comprising a stabiliser.

24. A composition according to claim 23, wherein the stabiliser is selected from diene-based compounds, phosphates, phenol compounds and epoxides, and mixtures thereof.

25. A composition according to claim 24 comprising an additional flame retardant.

26. A composition according to claim 25, wherein the flame retardant is selected from the group consisting of tri-(2-chloroethyl)-phosphate, (chloropropyl) phosphate, tri-(2,3-dibromopropyl)-phosphate, tri-(1,3-dichloropropyl)-phosphate, diammonium phosphate, various halogenated aromatic compounds, antimony oxide, aluminium trihydrate, polyvinyl chloride, a fluorinated iodocarbon, a fluorinated bromocarbon, trifluoro iodomethane, perfluoroalkyl amines, bromo-fluoroalkyl amines and mixtures thereof.

27. A heat transfer device containing a composition as defined in any of claims 13 to 26.

28. Use of a composition defined in any of claims 13 to 26 in a heat transfer device.

29. A heat transfer device according to claim 27 or the use according to claim 28, which is a refrigeration device.

30. A heat transfer device according to claim 29, which is selected from the group consisting of automotive air conditioning systems, residential air conditioning systems, commercial air conditioning systems, residential refrigerator systems, residential freezer systems, commercial refrigerator systems, commercial freezer systems, chiller air conditioning systems, chiller refrigeration systems, and commercial or residential heat pump systems.

31. A heat transfer device according to claim 29 or 30, which contains a compressor.

32. A method of cooling an article, which comprises condensing a composition as defined in claims 13 to 26 and thereafter evaporating the composition in the vicinity of the article to be cooled.

33. A method for heating an article, which comprises condensing a composition as defined in any one of claims 13 to 26 in the vicinity of the article to be heated and thereafter evaporating the composition.

34. A mechanical power generation device containing a composition as defined in any one of claims 13 to 26.

35. A mechanical power generating device according to claim 34, which is adapted to use a Rankine Cycle or modification thereof to generate work from heat.

36. A method of retrofitting a heat transfer device comprising the step of removing an existing heat transfer fluid and introducing a composition as defined in claims 13 to 26.

37. A method according to claim 36 wherein the heat transfer device is a refrigeration device.

38. A method according to claim 37 wherein the heat transfer device is an air-conditioning system.

39. A method of reducing the flammability of a composition by the addition of one or more compounds of formula (I) to (VI).

40. A method of preparing a compound of formula (I) comprising reacting a compound of formula (A) with a compound of formula (B): ##STR00020## wherein W is independently selected from the group consisting of H, F, Cl, Br, and I; X is independently selected from the group consisting of H, F, Cl, Br, and I; Y is independently selected from the group consisting of F, Cl, Br, and I; Z is independently selected from the group consisting of H, F, Cl, Br, or I; V is independently selected from the group consisting of CI and OH; n is an integer from 1 to 8; and n′ is an integer from 1 to 12.

41. A method according to claim 40 wherein W is H or F, preferably H.

42. A method according to claim 40 or 41 wherein X is H or F, preferably H.

43. A method according to any one of claims 40 to 42 wherein W is H; X is H; Y is independently selected from the group consisting of F, Cl, and I; and Z is independently selected from the group consisting of H, F, Cl and I.

44. A method according to any one of claims 40 to 43 wherein Y is F.

45. A method according to any one of claims 40 to 44 wherein Z is either H or F.

46. A method according to any one of claims 40 to 45 wherein V is Cl.

47. A method according to any one of claims 40 to 46 wherein n is an integer from 1 to 5.

48. A method according to any one of claims 40 to 47 wherein n′ is an integer from 1 to 10.

49. A method according to any of claims 40 to 48 wherein the ratio of compound of formula (A) to compound of formula (B) is at least 2:1.

50. A method of preparing a composition according to claim 13, comprising mixing a compound of formula (I) to (VI) with a heat transfer fluid.

51. A method of preparing a composition according to claim 17, comprising mixing the product of claims 40 to 49 with a heat transfer fluid.

52. A method according to claim 50 or 51 wherein the heat transfer fluid comprises one or more compounds selected from the group of (hydro)fluoroolefins (HFOs), hydrofluorocarbons (HFCs), chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrocarbons.

53. A method according to claim 52 wherein the heat transfer fluid comprises one or more compounds selected from the group of R-1234ze, R-1234yf, R-1233xf, R-1233zd, R-1243zf, R-134a, R-152a, R-32, R-161, R-125, R-134, propane, propylene, carbon dioxide, R-245fa, R-236fa, R-227ea, R-143a, n-butane, iso-butane and R-365mfc.

54. A method according to claim 53 wherein the heat transfer fluid comprises one or more compounds selected from the group of R-1234ze, R-1234yf, R-1233xf, R-1233zd, R-1243zf, R-134a, R-152a and R-32.

55. A method according to claim 54 wherein the heat transfer fluid comprises R-1234ze.

56. A method according to claim 54 wherein the heat transfer fluid comprises R-1234yf.

57. A method of preparing a compound of formula (II) comprising reacting pentafluoropropan-1-ol with a compound of formula (B), wherein n′ is 4 and W is OH or Cl.

58. A method according to claim 57 wherein W is Cl.

59. A method according to claim 57 or 58 wherein the ratio of pentafluoropropan-1-ol to compound of formula (B) is at least 2:1.

60. A method of preparing a compound of formula (III) comprising reacting pentafluoropropan-1-ol with a compound of formula (B), wherein n′ is 8 and W is OH or Cl.

61. A method according to claim 60 wherein W is Cl.

62. A method according to claim 60 or 61 wherein the ratio of pentafluoropropan-1-ol to compound of formula (B) is at least 2:1.

63. A method of preparing a compound of formula (IV) comprising reacting 2,2,3,3-tetafluoropropan-1-ol with a compound of formula (B), wherein n′ is 8 and W is OH or Cl.

64. A method according to claim 63 wherein W is Cl.

65. A method according to claim 63 or 64 wherein the ratio of 2,2,3,3-tetafluoropropan-1-ol to compound of formula (B) is at least 2:1.

66. A method of preparing a composition according to claim 12 comprising reacting 2,2,3,3,4,4,5,5-octofluoropentan-1-ol with a compound of formula (B′), wherein n′ is 4 and W is OH or Cl; and comprising reacting 2,2,3,3,4,4,5,5-octofluoropentan-1-ol with a compound of formula (B″), wherein n′ is 8 and W is OH or Cl.

67. A method according to claim 66 wherein W is Cl.

68. A method according to claim 66 or 67, which is conducted in one-step reaction.

69. A method according to any of claims 66 to 68 wherein the ratio of 2,2,3,3,4,4,5,5-octofluoropentan-1-ol to the combined amount of compounds of formula B′ and B″ is at least 2:1.

70. Use of any one of compounds of formula (I) to (VI) as a heat transfer agent.

Description

EXAMPLES

Synthesis of Compound of Formula (II)

[0079] ##STR00011##

[0080] 2,2,3,3,3-pentafluoropropan-1-ol (110 g, 0.73 mol) was charged to a 250 mL round bottom flask fitted with a condenser and dropping funnel. The alcohol was stirred and heated to 40° C. Adipoyl chloride (44.6 g, 0.24 mol) was charged to a dropping funnel and added slowly to the alcohol. The mixture was stirred at 40° C. for approximately 4 to 5 hours, allowed to cool to room temperature and then the excess alcohol was removed under vacuum. The remaining clear oil was filtered to remove particulates and then dried over activated molecular sieves. The reaction gave 78.5 g (78.5% yield) of a compound of Formula (II).

[0081] .sup.1H NMR (DMSO): δ 4.74-4.83 (t CH.sub.2), δ 2.41-2.47 (m C.sub.2H.sub.4), δ 1.53-1.62 (m C.sub.2H.sub.4) .sup.13C NMR (DMSO): δ 171.21 (s OC═O), δ 120.05 (t CF.sub.2), δ 116.26 (t CF.sub.2), δ 115.39-112.02 (m CF.sub.3), δ 57.79-58.71 (t CH.sub.2O), δ 32.35-32.51 (d CH.sub.2C═O), δ 23.28-23.62 (d CH.sub.2)

[0082] .sup.19F NMR (DMSO): δ −6.17-−5.49 (s 6F), δ −47.37-−45.47 (s 4F)

[0083] IR: 1764 cm.sup.−1 (OC═O), 1197 cm.sup.−1 (C—O), 1137 cm.sup.−1 (C—F)

[0084] TGA: One mass loss is seen giving a boiling range of 240-260° C. No impurities

[0085] Density: 1.42 g/ml

[0086] Viscosity: 7.06 cP

TABLE-US-00001 RPM Centipoise (cP) Torque (%) <10 Out of Range Out of Range 10 6.6 11 12 6.6 13.2 20 6.78 22.6 30 6.94 34.7 50 7.02 58.5 60 7.06 70.6 100 Out of Range Out of Range

Synthesis of Compound of Formula (III)

[0087] ##STR00012##

[0088] 2,2,3,3,3-pentafluoropropan-1-ol (96.6 g, 0.64 mol) was charged to a 250 mL round bottom flask fitted with a condenser and dropping funnel. The alcohol was stirred and heated to 40° C. Sebacoyl chloride (51.3 g, 0.21 mol) was charged to a dropping funnel and added slowly to the alcohol. The mixture was stirred at 40° C. for approximately 4 to 5 hours, allowed to cool to room temperature and then the excess alcohol was removed under vacuum. The remaining clear oil was filtered to remove particulates and then dried over activated molecular sieves. The reaction gave 40.9 g (40.9% yield) of a compound of Formula (III). The yield is lower than expected due to inadvertent loss of product before weighing.

[0089] .sup.1H NMR (DMSO): δ 4.73-4.82 (t CH.sub.2), δ 2.37-2.42 (t C.sub.2H.sub.4), δ 1.50-1.55 (m C.sub.2H.sub.4), δ 1.24 (s C.sub.4H.sub.8)

[0090] .sup.13C NMR (DMSO): δ 171.43 (s OC═O), δ 120.06 (t CF.sub.2), δ 108.69-116.27 (m CF.sub.3), δ 57.74-58.46 (t CH.sub.2O), δ 32.77 (s CH.sub.2C═O), δ 27.97-28.44 (m C.sub.2H.sub.4), δ 24.02-24.36 (d C.sub.2H.sub.4)

[0091] .sup.19F NMR (DMSO): δ −8.98-−8.29 (s 6F), δ −48.29 (s 4F)

[0092] IR: 1764 cm.sup.−1 (OC═O), 1197 cm.sup.−1 (C—O), 1149 cm.sup.−1 (C—F)

[0093] TGA: One mass loss is seen giving a boiling range of 280-310° C. No impurities

[0094] Density: 1.31 g/ml

[0095] Viscosity: 10.51 cP

TABLE-US-00002 RPM Centipoise (cP) Torque (%) <10 Out of Range Out of Range 10 10.08 16.8 12 10.10 20.2 20 10.26 34.2 30 10.40 52.0 50 10.51 87.6 60 Out of Range Out of Range

Synthesis of Compound of Formula (IV)

[0096] ##STR00013##

[0097] 2,2,3,3-tetrafluoropropan-1-ol (82.88 g, 0.63 mol) was charged to a 250 mL round bottom flask fitted with a condenser and dropping funnel. The alcohol was stirred and heated to 40° C. Sebacoyl chloride (50.05 g, 0.21 mol) was charged to a dropping funnel and added slowly to the alcohol. The mixture was stirred at 40° C. for approximately 4 to 5 hours, allowed to cool to room temperature and then the excess alcohol was removed under vacuum. The remaining clear oil was filtered to remove particulates and then dried over activated molecular sieves. The reaction gave 60 g (67% yield) of a compound of Formula (IV).

[0098] .sup.1H NMR (DMSO): δ 6.38-6.77 (tt, CF.sub.2H), δ 4.53-4.63 (t CH.sub.2), δ 2.37-2.42 (t C.sub.2H.sub.4), δ 1.51-1.56 (m C.sub.2H.sub.4), δ 1.25 (s C.sub.4H.sub.8)

[0099] .sup.13C NMR (DMSO): δ 171.77 (s OC═O), δ 117.81 (t CF.sub.2), δ 114.15-114.86 (t CF.sub.2), δ 105.46-112.92 (m CF.sub.2), δ 58.55-59.26 (t CH.sub.2O), δ 32.87 (s CH.sub.2C═O), δ 28.10-28.34 (m C.sub.2H.sub.4), δ 24.10 (s C.sub.2H.sub.4)

[0100] .sup.19F NMR (DMSO): δ −50.20-−50.17 (s 4F), δ −64.40-−64.36 (s 4F)

[0101] IR: 1756 cm.sup.−1 (OC═O), 1108 cm.sup.−1 (C—F)

[0102] TGA: One mass loss is seen giving a boiling range of 330-350° C.

[0103] Density: 1.28 g/ml

[0104] Viscosity: 26.33 cP

TABLE-US-00003 RPM Centipoise (cP) Torque (%) 2 Out of Range Out of Range 3 25.4 12.7 4 25.6 17.1 5 25.7 21.4 6 25.7 25.7 10 26.09 43.5 12 26.09 52.2 20 26.33 87.8 30 Out of Range Out of Range

Synthesis of 1:1 Combination of Compounds of Formula (V) and (VI)

[0105] ##STR00014##

[0106] Sebacoyl chloride (32.66 g, 0.14 mol) and adipoyl chloride (25.00 g, 0.14 mol) were charged to a 250 mL round bottom flask fitted with a condenser and dropping funnel. The acid chloride mixture was stirred at room temperature. 1H, 1H, 5H-Octafluoropentan-1-ol (133.31 g, 0.55 mol) was charged to a dropping funnel and added slowly to the mixture. The mixture was stirred at 40° C. for approximately 7 hours, allowed to cool to room temperature and then the reaction mixture was worked up. The remaining clear oil was filtered to remove particulates and then dried over activated molecular sieves. The reaction gave 123 g of compounds of Formula (V) and (VI).

[0107] .sup.1H NMR (DMSO): δ 6.85-7.23 (tt, CF.sub.2H), δ 4.73-4.83 (t CH.sub.2), δ 2.38-2.47 (m C.sub.2H.sub.4), δ 1.51-1.59 (m C.sub.2H.sub.4), δ 1.24 (s C.sub.4H.sub.8)

[0108] .sup.13C NMR (DMSO): δ 171.54 (s OC═O), δ 171.32 (s OC═O), δ 118.06-117.65 (m CF.sub.2), δ 115.09-113.53 (m CF.sub.2), δ 111.59-110.05 (m CF.sub.2), δ 109.64-107.45 (m CF.sub.2), δ 104.11-104.92 (m CF.sub.2) δ 58.16-58.86 (m CH.sub.2O), δ 32.39-33.13 (s x2 CH.sub.2C═O), δ 28.01-28.27 (d C.sub.2H.sub.4), 624.07 (s C.sub.2H.sub.4), δ 23.32 (s C.sub.2H.sub.4)

[0109] .sup.19F NMR (DMSO): δ −43.64-−43.54 (s 4F), δ −49.62-−49.37 (s 4F), δ −54.46-−54.19 (s 4F), δ −63.09-−62.90 (s 4F)

[0110] IR: 1759 cm.sup.−1 (OC═O), 1126 cm.sup.−1 (C—F)

[0111] TGA: One mass loss is seen giving a boiling range of 320 to 365° C. No impurities

[0112] Density: 1.49 g/mL

[0113] Viscosity: 41.04 cP

TABLE-US-00004 RPM Centipoise (cP) Torque (%) <2 Out of Range Out of Range 2 39.9 13.3 3 40.6 20.3 4 40.6 27.1 5 40.6 33.8 6 40.5 40.5 10 41.03 68.4 12 41.04 82.1 20 Out of Range Out of Range

[0114] The individually made oils (compounds of Formula (V) and (VI)) were then mixed together in 3 different molar ratios: 1:1, 1:2 and 2:1 respectively. Viscosity and density measurements were then performed on all mixtures.

TABLE-US-00005 Viscosity Oil mixture RPM Centipoise (cP) Torque (%) Density (g/ml) 1:1 2 36.0 12.0 1.49 3 36.6 18.3 4 36.4 24.3 5 36.6 30.5 6 36.9 36.9 10 37.12 62.0 12 37.74 74.7 1:2 2 35.4 11.8 1.47 3 37.2 18.6 4 36.9 24.6 5 37.2 31.0 6 37.3 37.3 10 37.37 62.3 12 37.19 74.4 2:1 2 35.4 11.8 1.51 3 35.8 17.9 4 37.0 24.7 5 36.6 30.5 6 37.0 37.0 10 37.13 61.9 12 37.19 74.4

Flammability

[0115] Selected fluorinated fluids of the invention were tested to assess their flammability and/or combustibility alone and mixed with fluorocarbon refrigerant compositions. It was found that the fluorinated species exhibited elevated combustion temperature compared to commercially available polyalkylene glycol (PAG) and polyol ester (POE) lubricant materials.

Experimental Method—Hot Manifold Testing

[0116] An assessment was made of the ease of ignition of the fluids when in contact with a hot metal surface, using the test apparatus and test method as described in ISO Standard ISO 20823:2003. In this test droplets of the fluid were allowed to fall vertically downwards onto an internally heated, cylindrical hot surface, inclined at a shallow angle to the horizontal, and which was additionally fitted with a horizontal gutter to trap liquid at one side of the cylindrical body. (The surface is hereinafter described as the “manifold”).

[0117] The temperature of the manifold was increased stepwise until ignition was observed. Observations on the character and vigour of ignition were also recorded during each test. Five fluids of the invention, two PAG type lubricants (Nippon Denso ND12 and Daphne FD46XG) and one POE lubricant (Emkarate RL68H) were tested. A perfluorinated lubricant material (DuPont Krytox™ GPL150) was also tested as a comparative example. The results are tabulated below:

TABLE-US-00006 Highest temperature Lowest without temperature ignition with ignition Fluid (° C.) (° C.) Observations Formula (V) 633 643 Immediate ignition Formula (VI) 608 615 Immediate ignition Formula (VII) 604 615 Immediate Compound of 626 635 30 s delay before formula (IV) ignition 2:1 Combination 636 643 28 s delay before of compounds ignition of Formula (V) and (VI) ND12 (PAG) 438 443 Immediate ignition; burning liquid collected FD46XG (PAG) 462 467 Immediate ignition; burning liquid collected RL68H (POE) 628 633 Immediate ignition; gas above tray also ignited by droplets Krytox GPL150 770 None observed Smoke but no flame in range 600-770° C.

[0118] It is evident that the fluids of the invention require significantly higher surface temperatures to initiate combustion than those of the PAG fluids. Two of the fluids tested also have ignition temperatures comparable or higher to that of the POE fluid tested. Both of these fluids exhibit significantly delayed and less vigorous combustion than the POE fluid.

Experimental Method—Testing in Refrigerant Mixtures

[0119] The combustion behaviour of mixtures of one of the fluids of the invention (2:1 combination of compounds of Formula (V) and (VI)) with the refrigerant fluid 2,3,3,3-tetrafluoropropene (R-1234yf) when in contact with a hot metal surface was investigated. Refrigerant R1234yf is proposed as a suitable fluid for automotive air-conditioning systems, where a leak from the system could result in a spray of refrigerant/oil mixture contacting hot engine surfaces.

[0120] The apparatus used comprised an enclosed cubical test chamber, 30 cm on a side, with transparent side and front faces and steel back, top and bottom faces. The two side faces were hinged to provide a means of pressure relief in the event of an ignition.

[0121] A horizontal, hollow, steel cylinder with closed front face, diameter ca 75 mm and length ca 70 mm, was mounted onto the steel back face of the chamber with its centre point approximately 160 mm above the base plate. This cylinder was heated on its inside surfaces from outside the test cell by using an oxy-acetylene torch whose flame jet was aimed into the cylinder. Thermocouples were spot-welded into the top and bottom of the cylinder and the heating torch gas rates were adjusted until the temperatures indicated on each thermocouple were steady and within 10 K of each other. Additional thermocouples were used to monitor the air temperature at top, middle and bottom of the test chamber. Once the hot surface was at steady state, a liquid mixture of refrigerant and lubricant was injected to the test chamber, using a short pipe section of Swagelok tubing (6 mm external diameter) as an injection point. The tube was centrally mounted in the base of the test chamber and protruded about 10 mm into the test chamber. This resulted in a vertical spray of droplets and vaporised refrigerant entering the chamber, where its momentum ensured rapid mixing into the chamber atmosphere. A sketch of the test cell is shown in FIG. 1 to illustrate the geometry used.

[0122] For each experiment a constant quantity (˜20 grams) of the refrigerant/oil mixture was placed in a feed reservoir vessel, isolated from the chamber by a solenoid valve and initially at lab ambient temperature (typically from 18 to 20° C.). A standard concentration of 3% by weight oil in refrigerant was used. This is typical of the oil content in refrigerant circulating in automotive air conditioning systems.

[0123] Video cameras were used to film the release and any subsequent ignition events. When the solenoid valve was opened the pressure inside the feed cylinder was monitored as an indication of whether the release had finished. The apparatus was monitored for 5 minutes after each injection for evidence of flame (visual and by observing the thermocouple readings). After each injection event an air purge was used to flush the feed lines and the test chamber before the next injection.

[0124] The temperature of the hot surface was progressively increased until an ignition event was observed. For each temperature where no ignition was observed at least one repeat test was carried out as a check on reproducibility.

[0125] It was found that the highest hot surface temperature at which no ignition was observed was 818° C. for the combination of R-1234yf with the combination of compounds of Formula (V) and (VI) fluid. The lowest temperature at which ignition was observed was 822° C.

[0126] A comparative test was made using R-1234yf with PAG lubricant ND12 (a lubricant intended for use with R-1234yf refrigerant). It was found that the highest hot surface temperature at which no ignition was observed with this mixture was 795° C. The lowest temperature at which ignition was observed was 802° C.

[0127] The fluorinated fluid of the invention thus retarded the onset of ignition in this test as compared to the PAG fluid at an equal mass loading in the refrigerant.