Polyol ester lubricants for refrigerating compressors operating at high temperatures

• US 5,833,876 A
• Filed: 06/07/1995
• Issued: 11/10/1998
• Est. Priority Date: 06/03/1992
• Status: Expired due to Term

• Current Assignee: Cognis International GmbH (BASF SE)
• Original Assignee: Henkel Corporation (Henkel AG & Co KGaA)
• Inventors: Schnur, Nicholas E., Zehler, Eugene R.
• Primary Examiner(s): DIAMOND, ALAN D
• Application Number:
  US08/482,632
• Time in Patent Office: 1,252 Days
• Field of Search: 252/52 A, 252/56 R, 252/56 S, 252/6 E, 252/68, 508/486, 508/485, 508/492, 508/493, 508/496, 508/497, 62/84, 62/468
• US Class Current: 252/68
• CPC Class Codes: C08G 75/029 Modification with organic compounds
• CPC Class Codes: C08K 5/37 Thiols
• CPC Class Codes: C08L 23/06 Polyethene
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 81/02 Polythioethers; Polythioether-ethers
• CPC Class Codes: C09K 2205/22 All components of a mixture being fluoro compounds
• CPC Class Codes: C09K 2205/24 Only one single fluoro component present
• CPC Class Codes: C09K 5/045 containing only fluorine as halogen
• CPC Class Codes: C10M 105/38 of polyhydroxy compounds
• CPC Class Codes: C10M 105/42 Complex esters, i.e. compounds containing at least three esterified carboxyl groups and derived from the combination of at least three different types of the following five types of compound: monohydroxy compounds, polyhydroxy compounds, monocarboxylic acids, polycarboxylic acids and hydroxy carboxylic acids
• CPC Class Codes: C10M 105/48 of carbonic acid
• CPC Class Codes: C10M 129/10 having hydroxy groups bound to a carbon atom of a six-membered aromatic ring
• CPC Class Codes: C10M 129/72 of polycarboxylic acids
• CPC Class Codes: C10M 129/76 containing free hydroxy or carboxyl groups
• CPC Class Codes: C10M 133/12 having amino groups bound to a carbon atom of a six-membered aromatic ring
• CPC Class Codes: C10M 133/44 Five-membered ring containing nitrogen and carbon only
• CPC Class Codes: C10M 135/06 Esters, e.g. fats
• CPC Class Codes: C10M 135/18 thiocarbamic type, e.g. containing the groups
• CPC Class Codes: C10M 135/30 containing hydroxy groups; Derivatives thereof
• CPC Class Codes: C10M 137/04 Phosphate esters
• CPC Class Codes: C10M 137/08 : Ammonium or amine salts
• CPC Class Codes: C10M 169/04 : Mixtures of base-materials and additives
• CPC Class Codes: C10M 171/008 : Lubricant compositions compatible with refrigerants
• CPC Class Codes: C10M 2203/06 : Well-defined aromatic compounds
• CPC Class Codes: C10M 2205/026 : Butene
• CPC Class Codes: C10M 2207/023 : having hydroxy groups bound to carbon atoms of six-membered aromatic rings
• CPC Class Codes: C10M 2207/024 : having at least two phenol groups but no condensed ring
• CPC Class Codes: C10M 2207/026 : with tertiary alkyl groups
• CPC Class Codes: C10M 2207/027 : Neutral salts thereof
• CPC Class Codes: C10M 2207/08 : Aldehydes; Ketones
• CPC Class Codes: C10M 2207/121 : having hydrocarbon chains of seven or less carbon atoms
• CPC Class Codes: C10M 2207/122 : monocarboxylic
• CPC Class Codes: C10M 2207/123 : polycarboxylic
• CPC Class Codes: C10M 2207/125 : having hydrocarbon chains of eight up to twenty-nine carbon atoms, i.e. fatty acids
• CPC Class Codes: C10M 2207/128 : containing hydroxy groups; Ethers thereof
• CPC Class Codes: C10M 2207/129 : having hydrocarbon chains of thirty or more carbon atoms
• CPC Class Codes: C10M 2207/16 : Naphthenic acids
• CPC Class Codes: C10M 2207/22 : Acids obtained from polymerised unsaturated acids
• CPC Class Codes: C10M 2207/281 : of (cyclo)aliphatic monocarboxylic acids
• CPC Class Codes: C10M 2207/282 : of (cyclo)aliphatic oolycarboxylic acids
• CPC Class Codes: C10M 2207/283 : of polyhydroxy compounds
• CPC Class Codes: C10M 2207/2835 : used as base material
• CPC Class Codes: C10M 2207/284 : of aromatic monocarboxylic acids
• CPC Class Codes: C10M 2207/285 : of aromatic polycarboxylic acids
• CPC Class Codes: C10M 2207/286 : of polymerised unsaturated acids
• CPC Class Codes: C10M 2207/287 : Partial esters
• CPC Class Codes: C10M 2207/288 : containing free carboxyl groups
• CPC Class Codes: C10M 2207/289 : containing free hydroxy groups
• CPC Class Codes: C10M 2207/30 : Complex esters, i.e. compounds containing at leasst three esterified carboxyl groups and derived from the combination of at least three different types of the following five types of compounds: monohydroxyl compounds, polyhydroxy xompounds, monocarboxylic acids, polycarboxylic acids or hydroxy carboxylic acids
• CPC Class Codes: C10M 2207/301 : used as base material
• CPC Class Codes: C10M 2207/302 : derived from the combination of monocarboxylic acids, dicarboxylic acids and dihydroxy compounds only and having no free hydroxy or carboxyl groups
• CPC Class Codes: C10M 2207/325 : used as base material
• CPC Class Codes: C10M 2207/34 : Esters having a hydrocarbon substituent of thirty or more carbon atoms, e.g. substituted succinic acid derivatives
• CPC Class Codes: C10M 2209/084 : Acrylate; Methacrylate
• CPC Class Codes: C10M 2211/022 : aliphatic
• CPC Class Codes: C10M 2211/06 : Perfluorinated compounds
• CPC Class Codes: C10M 2215/04 : having amino groups bound to acyclic or cycloaliphatic carbon atoms
• CPC Class Codes: C10M 2215/06 : having amino groups bound to carbon atoms of six-membered aromatic rings
• CPC Class Codes: C10M 2215/064 : Di- and triaryl amines
• CPC Class Codes: C10M 2215/065 : Phenyl-Naphthyl amines
• CPC Class Codes: C10M 2215/066 : Arylene diamines
• CPC Class Codes: C10M 2215/067 : Polyaryl amine alkanes
• CPC Class Codes: C10M 2215/068 : having amino groups bound to polycyclic aromatic ring systems, i.e. systems with three or more condensed rings
• CPC Class Codes: C10M 2215/08 : Amides
• CPC Class Codes: C10M 2215/082 : containing hydroxyl groups; Alkoxylated derivatives
• CPC Class Codes: C10M 2215/086 : Imides
• CPC Class Codes: C10M 2215/102 : Ureas; Semicarbazides; Allophanates
• CPC Class Codes: C10M 2215/12 : Partial amides of polycarboxylic acids
• CPC Class Codes: C10M 2215/14 : Containing carbon-to-nitrogen double bounds, e.g. guanidines, hydrazones, semicarbazones
• CPC Class Codes: C10M 2215/22 : Heterocyclic nitrogen compounds
• CPC Class Codes: C10M 2215/221 : Six-membered rings containing nitrogen and carbon only
• CPC Class Codes: C10M 2215/223 : Five-membered rings containing nitrogen and carbon only
• CPC Class Codes: C10M 2215/224 : Imidazoles
• CPC Class Codes: C10M 2215/225 : the rings containing both nitrogen and oxygen
• CPC Class Codes: C10M 2215/226 : Morpholines
• CPC Class Codes: C10M 2215/26 : Amines
• CPC Class Codes: C10M 2215/28 : Amides; Imides
• CPC Class Codes: C10M 2215/30 : Heterocyclic compounds
• CPC Class Codes: C10M 2217/028 : containing monomers having an unsaturated radical bound to a nitrogen-containing hetero ring
• CPC Class Codes: C10M 2217/06 : Macromolecular compounds obtained by functionalisation op polymers with a nitrogen containing compound
• CPC Class Codes: C10M 2219/02 : Sulfur-containing compounds obtained by sulfurisation with sulfur or sulfur-containing compounds
• CPC Class Codes: C10M 2219/022 : of hydrocarbons, e.g. olefines polyolefins C10M2221/041
• CPC Class Codes: C10M 2219/024 : of esters, e.g. fats
• CPC Class Codes: C10M 2219/044 : Sulfonic acids, Derivatives thereof, e.g. neutral salts
• CPC Class Codes: C10M 2219/062 : having carbon-to-sulfur double bonds
• CPC Class Codes: C10M 2219/066 : Thiocarbamic type compounds
• CPC Class Codes: C10M 2219/068 : Thiocarbamate metal salts
• CPC Class Codes: C10M 2219/082 : containing sulfur atoms bound to acyclic or cycloaliphatic carbon atoms
• CPC Class Codes: C10M 2219/087 : containing hydroxy groups; Derivatives thereof, e.g. sulfurised phenols
• CPC Class Codes: C10M 2219/088 : Neutral salts
• CPC Class Codes: C10M 2219/089 : Overbased salts
• CPC Class Codes: C10M 2219/10 : Heterocyclic compounds containing sulfur, selenium or tellurium compounds in the ring
• CPC Class Codes: C10M 2219/102 : containing sulfur and carbon only in the ring
• CPC Class Codes: C10M 2219/104 : containing sulfur and carbon with nitrogen or oxygen in the ring
• CPC Class Codes: C10M 2219/106 : Thiadiazoles
• CPC Class Codes: C10M 2219/108 : Phenothiazine
• CPC Class Codes: C10M 2223/04 : Phosphate esters
• CPC Class Codes: C10M 2223/041 : Triaryl phosphates
• CPC Class Codes: C10M 2223/042 : Metal salts thereof
• CPC Class Codes: C10M 2223/043 : Ammonium or amine salts thereof
• CPC Class Codes: C10M 2223/045 : Metal containing thio derivatives
• CPC Class Codes: C10M 2223/047 : Thioderivatives not containing metallic elements
• CPC Class Codes: C10M 2223/06 : having phosphorus-to-carbon bonds
• CPC Class Codes: C10M 2223/061 : Metal salts
• CPC Class Codes: C10M 2223/065 : containing sulfur
• CPC Class Codes: C10M 2227/061 : Esters derived from boron
• CPC Class Codes: C10M 2229/02 : Unspecified siloxanes; Silicones
• CPC Class Codes: C10M 2229/05 : containing atoms other than silicon, hydrogen, oxygen or carbon
• CPC Class Codes: C10N 2010/10 : Groups 5 or 15
• CPC Class Codes: C10N 2020/069 : Linear chain compounds
• CPC Class Codes: C10N 2020/071 : Branched chain compounds
• CPC Class Codes: C10N 2020/101 : Containing Hydrofluorocarbons
• CPC Class Codes: C10N 2040/00 : Specified use or application for which the lubricating composition is intended
• CPC Class Codes: C10N 2040/30 : Refrigerators lubricants or compressors lubricants
• CPC Class Codes: C10N 2040/32 : Wires, ropes or cables lubricants
• CPC Class Codes: C10N 2040/34 : Lubricating-sealants
• CPC Class Codes: C10N 2040/36 : Release agents or mold release agents
• CPC Class Codes: C10N 2040/38 : Conveyors or chain belts
• CPC Class Codes: C10N 2040/40 : Generators or electric motors in oil or gas winning field
• CPC Class Codes: C10N 2040/42 : Flashing oils or marking oils
• CPC Class Codes: C10N 2040/44 : Super vacuum or supercritical use
• CPC Class Codes: C10N 2040/50 : Medical uses
• CPC Class Codes: H01B 3/307 : Other macromolecular compounds

Abstract

A high quality lubricant for heavy duty service air conditioner and refrigerator compressors, especially those using chlorine free hydrofluorocarbon refrigerant working fluids, is provided by mixed esters of hindered polyols, most desirably di-pentaerythritol, usually mixed with some pentaerythritol, with a mixture of carboxylic acids including at least some of each of iso-pentanoic acid and iso-nonanoic acid.

Claims

1. A refrigerant working fluid consisting essentially of a chlorine-free, fluoro-group containing organic refrigerating heat transfer fluid and a balance of a composition with a viscosity between about 45 and about 157 centistokes at 40°

C. forming a single phase with the heat transfer fluid from -55°

C. to 100°

C. and consisting essentially of a mixture of polyol ester molecules in which at least about 85% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from PE and DPE, at least about 20% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from DPE and TPE, and at least about 95% of the acid molecules used to make the mixture consist of molecules having no more than ten carbon atoms each, the alcohol moieties and acyl groups being further selected subject to the constraints that (a) a total of at least about 3% of the acyl groups in the mixture are acyl groups of i-C₅ ;

(b) the ratio of the % of acyl groups in the mixture that contain 8 or more carbon atoms and are unbranched to the % of acyl groups in the mixture that are both branched and contain not more than six carbon atoms is not greater than about 1.56;

(c) the % of acyl groups in the mixture that contain at least nine carbon atoms, whether branched or not, is not greater than about 81; and

(d) a total of at least 20% of the acyl groups in the mixture are those of one of the trimethylhexanoic acids and only monobasic acids are used to make the mixture.

2. A refrigerant working fluid according to claim 1 consisting essentially of a chlorine-free, fluoro-group containing organic refrigerating heat transfer fluid and a balance of a composition with a viscosity between about 51 and about 145 centistokes at 40 °

C. forming a single phase with the heat transfer fluid from -55°

C. to 100°

C. and consisting essentially of a mixture of polyol ester molecules in which at least about 85% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from PE and DPE, at least about 26% of the alcohol moieties derived from DPE and TPE and at least about 98% of the acid molecules used to make the mixture consist of molecules having no more than ten carbon atoms each, the alcohol moieties and acyl groups being further selected subject to the constraints that (a) a total of at least about 3% of the acyl groups in the mixture are acyl groups of i-C₅ acid (b) the ratio of the % of the acyl groups in the mixture that contain 8 or more carbon atoms and are unbranched to the % of acyl groups in the mixture that are both branched and contain not more than six carbon atoms is not greater than about 1.56;

(c) the % of acyl groups in the mixture that contain at least nine carbon atoms, whether branched or not, is not greater than about 81 and (d) a total of at least 29% of the acyl groups in mixture are those of one of the trimethylhexanoic acids and only monobasic acids are used to make the mixture.

3. A refrigerant working fluid according to claim 2 consisting essentially of a chlorine-free, fluoro-group containing organic refrigerating heat transfer fluid and a balance of a composition with a viscosity between about 51 and about 134 centistokes at 40°

C. forming a single phase with the heat transfer fluid from -55°

C. to 100°

C. and consisting essentially of a mixture of polyol ester molecule in which at least about 95% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from PE and DPE, at least about 32% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from DPE and TPE and at least about 98% of the acid molecules used to make the mixture consist of molecules having no more than ten carbon atoms each, the alcohol moieties and acyl groups being further selected subject to the constraints that (a) a total of at least 7% of the acyl groups in the mixture are acyl groups of i-C₅ acid;

(b) the ratio of the % of acyl groups in the mixture that contain 8 or more carbon atoms and are unbranched to the % of acyl groups in the mixture that are both branched and contain not more than six carbon atoms is not greater than about 1.21, (c) the % of acyl groups in the mixture that contain at least nine carbon atoms, whether branched or not, is not greater than about 67; and

(d) a total of at least about 35% of the acyl groups in the mixture are those of one of the trimethyl hexanoic acid and only monobasic acids are used to make the mixture.

4. A refrigerant working fluid according to claim 3 consisting essentially of a chlorine-free, fluoro-group containing organic refrigerant heat transfer fluid and a balance of a composition with a viscosity between about 51 and about 123 centistokes at 40°

C. forming a single phase with the heat transfer fluid from -55°

C. the 100°

C. and consisting essentially of a mixture of polyol ester molecules in which at least about 95% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from PE and DPE, at least about 32% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from DPE and TPE and at least about 98% of the acid molecules used to make the mixture consist of molecules having no more than ten carbon atoms each, the alcohol moieties and acyl groups being further selected subject to the constraints that (a) a total of at least about 10% of the acyl groups in the mixture are acyl groups of i-C₅ acid;

(b) the ratio of the % of acyl groups in the mixture that contain 8 or more carbon atoms and are unbranched to the % of acyl groups in the mixture that are both branched and contain not more than six carbon atoms is not greater than about 1.00 (c) the % of acyl groups in the mixture that contain at least nine carbon atoms, whether branched or not, is not greater than about 67; and

(d) a total of at least about 35% of the acyl groups in the mixture are those of one of the trimethylhexanoic acids at least about 29% of the acyl groups in the mixture are 3,5,5-trimethylhexanoyl groups and only monobasic acids are used to make the mixture.

5. A refrigerant working fluid according to claim 4 consisting essentially of a chlorine-free, fluoro-group containing organic refrigerating heat transfer fluid and a balance of a composition with a viscosity between about 78 and about 123 centistokes at 40°

C. forming a single phase with the heat transfer fluid from -55°

C. to 100°

C. and consisting essentially of a mixture of polyol ester molecules in which at least about 98% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from PE and DPE, at least about 38% of the alcohol moieties are selected from the group consisting of the alcohol moieties derived from DPE and TPE, and at least about 98% of the acid molecules used to make the mixture consist of molecules having no more than ten carbon atoms each, the alcohol moieties and acyl groups being further selected subject to the constraints that (a) a total of at least about 10% of the acyl groups in the mixture are acyl groups of i-C₅ acid;

(b) the ratio of the % of acyl groups in the mixture that contain 8 or more carbon atoms and are unbranched to the % of acyl groups in the mixture that contain not more than six carbon atoms is not greater than about 1.00 (c) the % of acyl groups in the mixture that contain at least nine carbon atoms, whether branched or not, is not greater than about 67; and

(d) a total of at least about 41% of the acyl groups in the mixture are those of one of the trimethylhexanoic acids, at least about 29% of the acyl groups in the mixture are 3,5,5,-trimethylhexanoyl groups, and only monobasic acids are used to make the mixture.

6. A refrigerant working fluid according to claim 1 which also contains one or more additives selected from the group consisting of oxidation resistance and thermal stability improvers, corrosion inhibitors, metal deactivators, lubricity additives, viscosity index improvers, pour and floc point depressants, detergents, dispersants, antifoaming agents, anti-wear agents, and extreme pressure resistant additives.

7. A refrigerant working fluid according to claim 2 which also contains one or more additives selected from the group consisting of oxidation resistance and thermal stability improvers, corrosion inhibitors, metal deactivators, lubricity additives, viscosity index improvers, pour and floc point depressants, detergents, dispersants, antifoaming agents, anti-wear agents, and extreme pressure resistant additives.

8. a refrigerant working fluid according to claim 3 which also contains one or more additives selected from the group consisting of oxidation resistance and thermal stability improvers, corrosion inhibitors, metal deactivators, lubricity additives, viscosity index improvers, pour and floc point depressants, detergents, dispersants, antifoaming agents, anti-wear agents, and extreme pressure resistant additives.

9. A refrigerant working fluid according to claim 4 which also contains one or more additives selected from the group consisting of oxidation resistance and thermal stability improvers, corrosion inhibitors, metal deactivators, lubricity additives, viscosity index improvers, pour and floc point depressants, detergents, dispersants, antifoaming agents, anti-wear agents, and extreme pressure resistant additives.

10. A refrigerant working fluid according to claim 1 wherein the heat transfer fluid is selected from the group consisting of pentafluoroethane, 1,1-difluoroethane, 1,1,1-trifluoroethane, tetrafluoroethanes, and mixtures thereof.

11. A refrigerant working fluid according to claim 10 wherein the heat transfer fluid is 1,1,1,2-tetrafluoroethane.

12. A refrigerant working fluid according to claim 2 wherein the heat transfer fluid is selected from the group consisting of pentafluoroethane, 1,1-difluoroethane, 1,1,1-trifluoroethane, tetrafluoroethanes, and mixtures thereof.

13. A refrigerant working fluid according to claim 12 wherein the heat transfer fluid is 1,1,1,2-tetrafluoroethane.

14. A refrigerant working fluid according to claim 3 wherein the heat transfer fluid is selected from the group consisting of pentafluoroethane, 1,1-difluoroethane, 1,1,1-trifluoroethane, tetrafluoroethanes, and mixtures thereof.

15. A refrigerant working fluid according to claim 14 which consists essentially of at least 85% by weight 1,1,1,2-tetrafluoroethane and a balance of the composition.

16. A refrigerant working fluid according to claim 4 wherein the heat transfer fluid is 1,1,1,2-tetrafluoroethane.

17. The refrigerant working fluid according to claim 6 wherein the heat transfer fluid is 1,1,1,2-tetrafluoroethane.

18. A refrigerant working fluid according to claim 8 wherein the heat transfer fluid is 1,1,1,2-tetrafluoroethane.

19. A process for operating a refrigerator comprising cyclic compression, liquefaction, expansion, and evaporation of a heat transfer fluid, said heat transfer fluid consisting essentially of the refrigerant working fluid of claim 1.

20. A process for operating a refrigerator comprising cyclic compression, liquefaction, expansion, and evaporation of a heat transfer fluid, said heat transfer fluid consisting essentially of the refrigerant working fluid of claim 2.