Methods of incorporating additives into automotive lubricants

Abstract

In some embodiments, a method includes incorporating a miscibility additive into a first refrigerant lubricant to form an additive mixture under conditions that produce low foam generation. In some embodiments, a method includes fully incorporating a miscibility additive comprising a surfactant into a refrigerant lubricant with a non-grinding mill to form an additive mixture with low foam generation.

Description

TS0112-W001TITLE OF THE INVENTIONMETHODS OF INCORPORATING ADDITIVES INTO AUTOMOTIVE LUBRICANTSCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority of U.S. Provisional Application No. 63 / 691 ,587 filed September 6, 2024, the disclosure of which is incorporated herein by reference in its entirety.FIELD

[0002] The present disclosure relates to methods of introducing additives into refrigerant lubricants without generating excessive foam, moisture, or particulates during incorporation. More specifically, the present disclosure relates to methods and processes that aid in converting an automotive air-conditioning (A / C) system using a high global warming potential refrigerant to use a low global warming potential refrigerant without generating excessive foam or adding excessive moisture or particulates during conversion.BACKGROUND

[0003] Since the mid-1990s, automotive air-conditioning (A / C) systems have generally used the refrigerant 1 ,1 ,1 ,2-tetrafluoroethane (HFC-134a) in the vapor compression cycle. Now, due to environmental and societal pressures, global automotive manufacturers are transitioning to the low global warming potential (GWP) refrigerant, 2,3,3,3-tetrafluoropropene (HFO-1234yf), as the vehicle A / C refrigerant.However, there are several hundred million vehicles currently on the road that are using the older, high GWP refrigerant, HFC-134a. As the vehicle fleet ages, it will be necessary to recharge the vehicle A / C system. Vehicles greater than 10 years old may require A / C service. However, due to societal and global regulations, many countries are facing a hydrofluorocarbon (HFC) phasedown, where high GWP refrigerants are being phased out and will eventually become less available and more expensive. Therefore, there is a need to enable the existing HFC-134a vehicle fleet, estimated at several hundred million, a path to continued operation, thereby increasing the vehicle’sTS0112-W001 useful lifetime and meeting global sustainability goals. A vehicle that is ten to twenty years old may still be in good working condition but may need minor repairs or servicing to extend its lifetime. Vehicle A / C is a critical part of that sustainability requirement and will also need to be serviced or upgraded to be able to be serviced over the vehicle’s extended lifetime. Therefore, as HFCs become more difficult to find due to cost and availability issues, it will be imperative to use low GWP HFO type refrigerants in existing HFC containing A / C systems.

[0004] Although hydrofluorocarbons refrigerants exhibit good performance in automotive A / C systems, they are being phased down due to their high GWP. The refrigerant in vehicles currently using HFC-134a may need to be replaced with a low GWP refrigerant. The currently preferred choice is HFO-1234yf. In the United States, this conversion process to replace a high GWP refrigerant with a low GWP refrigerant is typically called a retrofit.

[0005] When an automotive service technician removes high GWP refrigerant from a vehicle A / C system, a significant amount of refrigerant lubricant, typically about 75-80%, is retained in the vehicle A / C compressor. High and low GWP refrigerant lubricants typically include polyalkylene glycol (PAG) lubricants for most non-electrified vehicle types. While both low and high GWP refrigerants generally use PAG lubricants, some low GWP A / C systems may require different lubricant packages. Therefore, the lubricant for the high GWP refrigerant is not necessarily miscible with lubricant for the low GWP refrigerant.

[0006] Since the remaining refrigerant lubricant may not be miscible with the low GWP refrigerant, a miscibility additive incorporated into the lubricant or A / C system may be necessary to enhance the low GWP refrigerant lubricant miscibility when the A / C system is converted to the new low GWP refrigerant. Miscibility enhancers are able to ensure that the two lubricants do not phase separate or form particulates, such as, for example, waxy particulates. While the miscibility enhancers are needed, they can also negatively impact the vehicle A / C system if they are not incorporated correctly during the vehicle A / C conversion or retrofit process.TS0112-W001

[0007] Foam formation can be a significant issue during the incorporation. The miscibility additive may contain one or more dispersants or surfactants that are surfaceactive and known to generate foam when agitated. However, without agitation, the miscibility additive may not be fully incorporated into the remaining lubricant and therefore not able to provide miscibility benefits between the low GWP refrigerant, the remaining high GWP lubricant, and the low GWP lubricant.

[0008] Additionally, refrigerant lubricants are typically hydroscopic, so proper care must be taken to ensure that additional moisture is not inadvertently added to the system while incorporating the miscibility additive with the lubricant. If not handled properly, these issues could lead to poor product quality, resulting in poor vehicle A / C performance.SUMMARY

[0009] Converting from a high GWP refrigerant to a low GWP refrigerant is not simple and straight forward. There is a need for one or more miscibility additives that improves the miscibility of the old refrigerant lubricant with the new low GWP refrigerant. The one or more miscibility additives ensures miscibility of the new low GWP refrigerant while not negatively impacting the compressor or A / C performance. The existing compressor continues to work across the same operating temperature range with the low GWP refrigerant. The miscibility additive also ensures that parameters such as, for example, dynamic and kinetic viscosity of the new lubricant package and total acid number (TAN), and moisture are not negatively impacted.

[0010] In an exemplary embodiment, a method includes incorporating a miscibility additive into a first refrigerant lubricant to form an additive mixture under conditions that produce low foam generation.

[0011] In an exemplary embodiment, a method includes fully incorporating a miscibility additive comprising a surfactant into a refrigerant lubricant with a non-grinding mill to form an additive mixture with low foam generation.TS0112-W001BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 schematically shows a cross sectional view of a container holding an additive mixture with molecular sieves for injection into an A / C system.DETAILED DESCRIPTION

[0013] Provided are methods and processes that incorporate a miscibility additive into an A / C system that provides miscibility between the remaining lubricant for the previous high GWP refrigerant, without introducing foam, moisture, or particulates at levels that would negatively the performance of the A / C system.

[0014] As used herein, “high GWP refrigerant” refers to any refrigerant having a 100- year GWP of 150 or greater. GWP is an index for estimating relative global warming contribution due to atmospheric emission of a kilogram of a particular greenhouse gas compared to emission of a kilogram of carbon dioxide. GWP can be calculated for different time horizons showing the effect of atmospheric lifetime for a given gas. The GWP for the 100-year time horizon is commonly the value referenced. For mixtures, a weighted average can be calculated based on the individual GWPs for each component.

[0015] In some embodiments, the high GWP refrigerant includes a hydrofluorocarbon (HFC). In some embodiments, the HFC includes HFC-134a. HFC-134a has a GWP of 1530 according to the United Nations Intergovernmental Panel on Climate Control (IPCC), which provides vetted values for refrigerant GWPs in official assessment reports (ARs.) The fourth assessment report is denoted as AR4, the fifth assessment report is denoted as AR5, and the sixth assessment report is denoted as AR6. The GWP values reported for refrigerant blends of the present invention herein refer to the AR4 values, which regulating bodies are currently using for legislation. AR6 is the most recent published report. It will be understood by those skilled in the art that the GWP values may refer to the AR4 or AR6 values.

[0016] In some embodiments, the remaining lubricant for the high GWP refrigerant includes a polyalkyl glycol (PAG).TS0112-W001

[0017] In some embodiments, a method incorporates a miscibility additive into a refrigerant lubricant to form an additive mixture under conditions that produce low foam generation.

[0018] In some embodiments, the method incorporates the miscibility additive into the refrigerant lubricant to form the additive mixture under conditions that produce low moisture addition.

[0019] In some embodiments, the method incorporates the miscibility additive into the refrigerant lubricant to form the additive mixture under conditions that produce low particulate addition.

[0020] In some embodiments, the refrigerant lubricant is a lubricant for a low GWP refrigerant.

[0021] As used herein, “low GWP refrigerant” refers to any refrigerant having a 100- year GWP of less than 150. An appropriate GWP for a low GWP refrigerant may include, but is not limited to, less than 150, less than 100, less than 50, less than 10, less than 5, less than 1 , or any value, range, or sub-range therebetween.

[0022] In some embodiments, the low GWP refrigerant includes a hydrofluoroolefin (HFO). Appropriate low GWP refrigerants may include, but are not limited to, HFO- 1234yf, E-1 ,3,3,3-tetrafluoropropene (HFO-1234zeE), Z-1 ,3,3,3-tetrafluoropropene (HFO-1234zeZ), E-1-chloro-3,3,3-trifluoropropene (HFO-1233zdE), Z-1 -chloro-3,3,3- trifluoropropene (HFO-1233zdZ), Z-1 ,1 ,1 ,4,4,4-hexafluoro-2-butene (HFO-1336mzzZ), E-1 ,1 ,1 ,4,4,4-hexafluoro-2-butene (HFO-1336mzzE), hydrocarbons such as propane, or blends including any of these. In some embodiments, the HFO includes HFO-1234yf. HFO-1234yf has a GWP of 0.5 according to the United Nations IPCC AR6. Appropriate low GWP refrigerants may include, but are not limited to, the HFOs disclosed in U.S. Patent No. 8,426,657, the disclosure of which is incorporated herein by reference in its entirety.

[0023] In some embodiments, the low GWP refrigerant includes minor amounts of HFCs or other HFO compounds. For example, when the refrigerant includes HFO- 1234yf, the refrigerant may include up to 1 wt%, alternatively up to 0.5 wt%,TS0112-W001 alternatively up to 0.1 wt% of one or more of 1 ,1 ,1 ,2-tetrafluoro-2,3-dichloropropane (HCFC-234bb), 2-chloro-1 ,1 ,1 ,2-tetrafluoropropane (HCFC-244bb), 3-ch loro-1 , 1 ,1 , 2- tetrafluoropropane (HCFC-244eb), 1 ,1 ,1 ,2-tetrafluoropropane (HFC-254eb), 1 ,1 ,1- trifluoropropane (HFC-263fb), 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), 1 ,1 , 1 ,2, 2- pentafluoropropane (HFC-245cb), 3,3,3-trifluoropropene (HFO-1243zf), methyl chloride (HCC-40), 1 ,2,3,3,3-pentafluoropropene (HFO-1225ye), 1 ,1 ,3,3,3-pentafluoropropene (HFO-1225zc), 1 -chloro-1 -fluoroethylene (HCFO-1131 a), E-1 -chloro-2 -fluoroethylene (HCFO-E-1131 ), Z-1 -chloro-2 -fluoroethylene (HCFO-Z-1131 ), 1 -chloro-1 , 1 - difluoroethane (HCFC-142b), 1 -chloro-1 , 2, 2, 2-tetrafluoroethane (HCFC-124), 1 -chloro- 1 ,2-difluoroethylene (HCFO-1122a), 2-chloro-1 ,1 -difluoroethylene (HCFO-1122), E- 1 ,3,3,3-tetrafluoropropene (HFO-E-1234ze), Z-1 ,3,3,3-tetrafluoropropene (HFO-Z- 1234ze), and vinyl chloride (HFO-1140).

[0024] Appropriate lubricants for a low GWP refrigerant may include, but are not limited to, PAG, polyester oil (POE), polyvinyl ether (PVE), and combinations thereof.

[0025] Appropriate lubricants for the low GWP refrigerant may include, but are not limited to, a PAG lubricant, such as, for example, the PAG marketed under the trade name FD46XG (Idemitsu Kosan Co., Ltd., Tokyo, Japan), the PAGs marketed under the trade names ND-8 and ND-12 (Idemitsu Kosan Co., Ltd.), the PAG marketed under the trade name PS-D1 (ACDelco, Warren, Ml), the PAG marketed under the trade name RL-897 (Dow Chemical Company), and the PAGs marketed under the trade names SP- A2, SP-10, and SP-15 (Sanden International, Inc., Wylie, TX); a POE lubricant, such as, for example, the POE marketed under the trade name ND-11 (ENEOS Corporation, Tokyo, Japan); a PVE lubricant; alkylated naphthalene; epoxylated naphthalene; and combinations thereof.

[0026] Appropriate amounts of the refrigerant lubricant in the additive mixture are selected such that upon addition of the additive mixture to the remaining lubricant for the high GWP refrigerant, the resulting lubrication composition includes an amount of the lubricant that approximately replaces the amount of lubricant for the high GWP refrigerant that was removed during removal of the high GWP refrigerant.TS0112-W001

[0027] In some embodiments, the incorporation method solves problems associated with converting an automotive A / C system from a high GWP refrigerant such as HFC- 134a to a low GWP refrigerant such as HFO-1234yf.

[0028] In some embodiments, the miscibility additive includes one or more compounds that are generally known as surfactants or surface-active agents. These miscibility additives generally have hydrophobic and hydrophilic moieties. Surfactants are known to generate foam upon agitation. Therefore, incorporating a surfactant into the existing PAG lubricants requires an innovative method.

[0029] In some embodiments, the miscibility additive includes at least one surfactant or surface-active agent. In some embodiments, the surfactant includes a dispersant that can disperse particulates such that small particulates do not aggregate, but rather stay dispersed such that the small particulates do not impact compressor performance. In some embodiments, the surfactant includes a wetting agent. In some embodiments, the surfactant is biodegradable. In some embodiments, the surfactant is free of or substantially free of fluorination.

[0030] Appropriate surfactants may include, but are not limited to, polyether surfactants, such as, for example, primary alcohol ethoxylates, secondary alcohol ethoxylates, and block copolymers of ethylene oxide and propylene oxide; hexamethyldisiloxane (HMDSO); polysiloxanes; and hydrocarbon surfactants.

[0031] Appropriate surfactants may include, but are not limited to, commercially- available surfactants marketed under the trade name Carbowet (Evonik Industries AG, Essen, Germany), such as, for example, Carbowet™ GA-100 and Carbowet™ 109; commercially-available surfactants marketed under the trade name Cirrasol (Croda International PLC, Snaith, UK), such as, for example, Cirrasol™ G-1086 and Cirrasol™ G-1096; commercially-available surfactants marketed under the trade name Dapro (Elementis Specialties, Inc., East Windsor, NJ), such as, for example, Dapro® DF 451 ; commercially-available surfactants marketed under the trade name Dowanol (Dow Chemical Company, Midland, Ml), such as, for example, Dowanol™ DPM and Dowanol™ PM Glycol Ether; commercially-available surfactants marketed under the trade name Igepal (Rhodia Operations, La Defense, France), such as, for example,TS0112-W001Igepal® CA-407, Igepal® CO-630, Igepal® CO-890, and Igepal® CTA-639W; commercially-available surfactants marketed under the trade name Tamol (Dow Chemical Company), such as, for example, Tamol® 731 A; commercially-available surfactants marketed under the trade name Tergitol (Dow Chemical Company), such as, for example, Tergitol™ 15-S-9, Tergitol™ 15-S-12, Tergitol™ 15-S-20, Tergitol™ L- 62, Tergitol™ L-64, Tergitol™ NP-10, Tergitol™ TMN-6, and Tergitol™ TMN-10; commercially-available surfactants marketed under the trade name Triton (Dow Chemical Company), such as, for example, Triton™ GR-7M and Triton™ X-100; polyoxyethylene Sorbitol / Sorbitan Fatty Acid Esters” family, which includes the following products Ethox TO-20, Cirrasol G-1096 and Cirrasol G-1086; and co-emulsifiers that create emulsions with lower levels of agitation (pair of surfactant of co-emulsifiers), such as TO-20 / Hexamethyldisiloxane, G-1096 / Ethal NP9, G-1086 / Ehtal NP9 and the like.

[0032] Appropriate amounts of the surfactant in the additive mixture are such that upon addition of the additive mixture to the remaining lubricant for the high GWP refrigerant, the resulting lubrication composition includes an amount of surfactant in the range of about 1 wt% to about 5 wt% surfactant, alternatively about 2 wt% to about 4 wt%, alternatively about 3 wt%, alternatively about 1 wt% to about 2 wt%, alternatively about 2 wt% to about 3 wt%, alternatively about 3 wt% to about 4 wt%, or any value, range, or sub-range therebetween.

[0033] In some embodiments, the additive mixture includes a stabilizer for the low GWP refrigerant. In some embodiments, the stabilizer includes at least one inhibitor compound that inhibits, if not eliminates, an HFO from interacting with another compound and forming dimers, oligomers, homopolymers, or polymeric products.

[0034] Appropriate inhibitors may include, but are not limited to, hydrocarbons such as cyclic monoterpenes (e.g., limonene, pinene, a-pinene, [3-pinene, and terpinene); lipophilic organic compounds such as tocopherols (e.g., a-tocopherol) or butylated hydroxytoluene (BHT); phenols or aromatic organic compounds having at least one chemical moiety -C6H4(OH) (e.g., benzene-1 ,4-diol, 4-methoxyphenol); and mixtures thereof. Specific examples of inhibitor compounds may include at least one member selected from limonene (particularly D-limonene), a-terpinene, pinene, a-pinene, 3-pinene, a-tocopherol, butylated hydroxytoluene (BHT), 4-methoxyphenol, benzene-1 ,4- diol, and mixtures thereof. In one embodiment, the inhibitor composition includes a liquid at a temperature from about -80°C to about 180°C, about -70°C to about 170°C, and in some cases about -60°C to about 160°C. By “stabilized” it is meant to refer to a composition including an effective amount of at least one inhibitor compound that inhibits, if not eliminates, a fluoroethylene from interacting with another compound and forming dimers, oligomers, homopolymers, or polymeric products.

[0035] In some embodiments, the stabilizer includes at least one acid scavenger. The stabilizer may be present at about 0.0001 % to about 1 %, by weight, in the additive mixture.

[0036] Appropriate acid scavengers may include, but are not limited to, a siloxane, an activated aromatic compound, or a combination of both. The siloxane may be any molecule having a siloxy functionality. The siloxane may include an alkyl siloxane, an aryl siloxane, or a siloxane containing mixtures of aryl and alkyl substituents. For example, the siloxane may be an alkyl siloxane, including a dialkylsiloxane or a polydialkylsiloxane. Preferred siloxanes include an oxygen atom bonded to two silicon atoms. For example, the siloxane may be a siloxane of the following Formula: Ri[Si(R2R3)4O]nSi(R2R3)R4, where n is 1 or more. Siloxanes of this Formula may have n that is preferably 2 or more, more preferably 3 or more, (e.g., about 4 or more). Siloxanes of this Formula have n that is preferably about 30 or less, more preferably about 12 or less, and most preferably about 7 or less. Preferably the R4 group is an aryl group or an alkyl group. Preferably the R2 groups are aryl groups or alkyl groups or mixtures thereof. Preferably the R3 groups are aryl groups or alkyl groups or mixtures thereof. Preferably the R4 group is an aryl group or an alkyl group. Preferably R1, R2, R3, R4, or any combination thereof are not hydrogen. The R2groups in a molecule may be the same or different. Preferably the R2 groups in a molecule are the same. The R2 groups in a molecule may be the same or different from the R3 groups. Preferably, the R2groups and R3 groups in a molecule are the same. Preferred siloxanes include siloxanes of this Formula, where R1, R2, R3, R4, Rs, or any combination thereof is a methyl, ethyl, propyl, or butyl group, or any combination thereof. Exemplary siloxanesTS0112-W001 that may be used include hexamethyldisiloxane, polydimethylsiloxane, polymethylphenylsiloxane, dodecamethylpentasiloxane, decamethylcyclopentasiloxane, decamethyltetrasiloxane, octamethyltrisiloxane, or any combination thereof.

[0037] In some embodiments, the additive mixture includes an ultraviolet dye. In some embodiments, the ultraviolet dye fluoresces when exposed to ultraviolet light to enable detection of the location of a refrigerant leak. In some embodiments, the dye is solubilized in the lubricant and then blended with the refrigerant.

[0038] In some embodiments, the dye is an ultraviolet dye that absorbs light in the ultraviolet or near ultraviolet region of the electromagnetic spectrum. Any compatible dye can be included in the additive mixture. Appropriate of compatible dyes may include, but are not limited to, at least one compound containing a fluorescein species selected from the derivatives of 6-hydroxy-3H-xanthen-3-one and having an absorbance peak from about 425 to about 433 nm, another absorbance peak from about 292 to about 295 nm, and, in some cases, a third absorbance peak from about 243 to about 250 nm. Absorbance peaks may be measured using UV-Vis. Compatible dyes may also be characterized using Fourier-transform infrared (FTIR) spectroscopy as having peaks between about 700 to about 800 cm'1, about 1000 to about 1100 cm'1, about 1200 to about 1300 cm'1, and / or about 1400 to about 1600 cm'1. The amount of dye can range from about 30 to about 0.001 wt%, alternatively about 20 to about 0.001 wt%, alternatively about 5 to about 0.001 wt%, or any value, range, or sub-range therebetween, based on the total weight of the additive mixture. The dye, lubricant, HFO, and inhibitor, among other components of the stabilizer, can be combined in any suitable sequence. In some embodiments, dye is solubilized in lubricant, followed by addition of HFO containing an inhibitor. In some embodiments, dye is solubilized in lubricant containing inhibitor, followed by addition of HFO.

[0039] Appropriate ultraviolet dyes may include, but are not limited to, those disclosed in International Application Publication No. WO 2023 / 141098, the disclosure of which is incorporated herein by reference in its entirety.TS0112-W001

[0040] Additionally, the remaining PAG lubricant, the added lubricant, and the prospective miscibility additive have hydrophilic moieties and are prone to pick up and increase in moisture content. Excessive moisture content in an A / C system can lead to degradation of the refrigerant and lubricant and also rusting of the metal heat exchangers. In exemplary embodiments, the incorporation method maintains the moisture content in the resulting lubricant mixture below 100 parts-per-million (ppm), alternatively at 50 ppm or less, ideally less than 25 ppm.

[0041] In exemplary embodiments, an incorporation method aids in converting an A / C system from a high GWP refrigerant to a low GWP refrigerant with low foam generation, low moisture addition, and low particulate addition.

[0042] As used herein, “low foam generation” refers to the introduction of less than 5% foam, by volume, relative to the liquid volume of the resulting additive mixture during the incorporation method.

[0043] As used herein, “low moisture addition” refers to addition of less than 100 ppm water to the A / C system during the incorporation method.

[0044] As used herein, “low particulate addition” refers to addition of less than 100 ppm solid particulates to the A / C system during the incorporation method.

[0045] In some embodiments, the incorporation method further includes replacing a high GWP refrigerant with a low GWP refrigerant.

[0046] In some embodiments, the conversion method includes removing a portion of the current lubricant with the high GWP refrigerant and adding an additive mixture including a miscibility additive and an additional lubricant that combines with the remaining lubricant to form a lubrication composition that is miscible with the low GWP refrigerant at operating temperatures and pressures of the A / C system.

[0047] In some embodiments, the incorporation method includes low agitation to incorporate the miscibility additive into the lubricant with low foam generation. In some embodiments, the low agitation occurs in a non-grinding mill.TS0112-W001

[0048] As used herein, a “non-grinding mill” refers to a grinding mill without any milling medium. In some embodiments, the non-grinding mill is a roller mill without a roller. In some embodiments, the non-grinding mill is a ball grinder without a ball. In some embodiments, the non-grinding mill is an attrition mill without a milling medium. In some embodiments, the non-grinding mill is a commercial grinding mill modified to include no milling medium.

[0049] In some embodiments, the low agitation is achieved at low speed and low energy by a roller mill or ball mill, / .e., without the roller mill metal or porcelain ball, that is otherwise empty except for the miscibility additive, lubricant, and optionally other components to be incorporated into the additive mixture to incorporate the miscibility additive into the lubricant with low foam generation.

[0050] Since there is no reduction in particle sizing needed from the mill, but rather only a slow agitation and incorporation, the energy imparted by the media-less mill to the components of the additive mixture is quite low. In exemplary embodiments, the energy translation to the fluids being mixed is very low such that there is no heat generation or heat loss between the two fluids being mixed. For a roller mill, this energy is estimated to be less than 15% of the power consumed to run the roller mill with the rollers.

[0051] An appropriate level of agitation from such a non-grinding mill may include, but is not limited to, about 100 revolutions-per-minute (RPM) or less, alternatively about 75 RPM or less, alternatively about 50 RPM or less, or any value, range, or sub-range therebetween.

[0052] In some embodiments, the incorporation occurs without the use of a highspeed rotor or stator type mill, including high-speed rotor or stator type mills marketed under the trade names Dispermat (VMA-Getzmann GmbH, Reichshof, Germany), Hockmeyer (Hockmeyer Equipment Corporation, Elizabeth City, NC), and Kady (Kady International Inc., Scarborough, ME).

[0053] In some embodiments, the level of foam generation is determined by visual inspection.TS0112-W001

[0054] In some embodiments, the level of foam generation is measured in a graduated cylinder. In some embodiments, the measuring includes comparing the foam height to the liquid height of the additive mixture. In this method, a known weight, typically 100 grams, of the test sample is gently poured into a 1000-mL graduated cylinder such that the foam is not disturbed. The liquid level is noted and the foam level is also noted as the amount above the liquid level. In this manner, the foam level from test to test can be determined as an amount in mL. As used herein and measured by this method, low foam generation refers to a foam height that is less than 5 mL, alternatively less than 3 mL, alternatively less than 2 mL, or any value, range, or subrange therebetween.

[0055] In some embodiments, the stability of the generated foam is measured with a graduated cylinder. In this case, the change in the foam height over time is measured. Measurement of the stability of the foam may be as important as measurement of foam generation. In this method, foam generation is first measured. To further note the foam stability, the foam height is measured at various later times, such as every 15 minutes for up to about two hours of total time. At the end of the two hours, a graph, noting the foam height on the y-axis vs the time in minutes on x-axis, is generated. A less stable foam exhibits a greater foam height reduction.

[0056] In some embodiments, even low speed or low energy agitation is insufficient to provide incorporation without generating an unacceptable level of foam. In such embodiments, the method includes reducing foam after incorporation of the miscibility additive into the added lubricant to form an additive mixture and before the additive mixture is delivered into the system.

[0057] In some embodiments, the foam reducing is by a physical method, such as, for example, a mesh screen or a filter that breaks up the foam. As the foam passes over the mesh screen, the gas entrained within the foam bubbles hits the screen and is liberated from the additive mixture.

[0058] In some embodiments, the mesh screen ensures low particulate addition by preventing some particulates in the additive mixture from passing through the mesh screen.TS0112-W001

[0059] An appropriate United States mesh size for the mesh screen may include, but is not limited to, 400 mesh or greater (37 pm or less opening size), alternatively 600 mesh or greater (16 pm or less), alternatively 800 mesh or greater (12 pm or less), alternatively 1000 mesh or greater (9 pm or less), or any value, range, or sub-range therebetween.

[0060] In some embodiments, the method includes incorporating a defoamer into the lubricant, miscibility additive, or additive mixture of lubricant and miscibility additive that reduces foam intrusion into the additive mixture.

[0061] Appropriate defoamers may include, but are not limited to, a long chain alcohol, a silicone, a siloxane, a silica, or combinations thereof.

[0062] In some embodiments, the defoamer includes a long chain alcohol. As used herein, “long chain alcohol” refers to any alcohol including a hydrocarbon chain of at least 6 carbon atoms, such as, for example, at least 8 carbon atoms, at least 10 carbon atoms, at least 12 carbon atoms, at least 14 carbon atoms, at least 16 carbon atoms, at least 18 carbon atoms, or at least 20 carbon atoms. The hydrocarbon chain may be saturated or unsaturated but is preferably acyclic. The long chain alcohol preferably includes no other functional groups.

[0063] In some embodiments, the silicone includes a silicone oil or a silicone glycol.

[0064] In some embodiments, the siloxane includes a polydimethylsiloxane.

[0065] In some embodiments, the silica includes a hydrophobic silica in a silicone oil.

[0066] An appropriate amount of defoamer may include, by weight of the additive mixture, up to about 1 %, alternatively about 0.1 % to about 1 %, alternatively about 0.1 % to about 0.5%, alternatively about 0.5% to about 1 %, alternatively about 0.1 % to about 0.3%, or any value, range, or sub-range therebetween.

[0067] In some embodiments, the method includes contacting the miscibility additive, the added lubricant, or the additive mixture to molecular sieves prior to introduction to the A / C system to reduce moisture in the resulting additive mixture. AppropriateTS0112-W001 molecular sieves may include, but are not limited to, an aluminosilicate, a porous glass, an active carbon, or a clay.

[0068] In some embodiments, the aluminosilicate includes a zeolite. Appropriate zeolites may include, but are not limited to, zeolite 3A, zeolite 4A, zeolite 5A, zeolite 13X, zeolite LSX, zeolite AW-300, zeolite AW-500. In some embodiments, the zeolite is one of zeolite 3A, zeolite 4A or zeolite 5A.

[0069] In some embodiments, the molecular sieves are added to the combined low GWP refrigerant and miscibility additive prior to the incorporation with the added lubricant to form the additive mixture.

[0070] In some embodiments, the molecular sieves are added to the miscibility additive prior to the incorporation with the added lubricant to form the additive mixture.

[0071] In some embodiments, the molecular sieves are added to the added lubricant prior to the incorporation with the miscibility additive to form the additive mixture.

[0072] In some embodiments, the miscibility additive, added lubricant, or additive mixture is passed across a packed molecular sieve cartridge before introduction into the A / C system.

[0073] In some embodiments, the additive mixture is applied to an A / C system. In some embodiments, the additive mixture is injected into the A / C system. In some embodiments, the injection is by hand from a container. In some embodiments, the low GWP refrigerant aids in applying the additive mixture to the A / C system.

[0074] The FIG. shows a container 10 for injecting the additive mixture 12 into a A / C system. The container 10 includes a container body 14 and a plunger 16. A packed column 20 containing molecular sieves 22 may be integral with the distal end of the container body 20 or may be attachable to the distal end. The mesh size of a mesh screen 24 on the distal end of the container limits particulates including the molecular sieves 22 from passing through the mesh screen 24. The plunger 16 may be actuated manually by hand.TS0112-W001

[0075] The additive mixture 12 may include the miscibility additive, the added lubricant, optionally a defoamer, and optionally a low GWP refrigerant. The low GWP refrigerant may aid in pushing the additive mixture 12 through the packed column 20.

[0076] In some embodiments, the incorporation occurs in the container 10. In some embodiments, the incorporation forms an additive mixture, by weight, of about 4% to about 25% miscibility additive and about 75% to about 96% added lubricant, alternatively about 4% to about 20% miscibility additive and about 80% to about 96% added lubricant, alternatively about 5% to about 25% miscibility additive and about 75% to about 95% added lubricant, alternatively about 8% to about 16% miscibility additive and about 84% to about 92% added lubricant, alternatively about 10% to about 20% miscibility additive and about 80% to about 90% added lubricant, or any value, range, or sub-range therebetween.

[0077] In some embodiments, the injection occurs with the aid of the low GWP refrigerant in the container. In some embodiments, the injection injects, by weight, about 20% to about 50% low GWP refrigerant and about 50% to about 80% additive mixture, alternatively about 30% to about 45% low GWP refrigerant and about 55% to about 70% additive mixture, alternatively about 35% to about 40% low GWP refrigerant and about 60% to about 65% additive mixture, alternatively about 85% to about 90% low GWP refrigerant and about 10% to about 15% additive mixture, or any value, range, or sub-range therebetween.OTHER EMBODIMENTS

[0078] Embodiment 1 : a method comprising incorporating a miscibility additive into a first refrigerant lubricant to form an additive mixture under conditions that produce low foam generation.

[0079] Embodiment 2: the method of embodiment 1 , wherein the miscibility additive comprises a surfactant.

[0080] Embodiment 3: the method of embodiment 2, wherein the surfactant is selected from the group consisting of a primary alcohol ethoxylate surfactant, aTS0112-W001 secondary alcohol ethoxylate surfactant, a block copolymer of ethylene oxide and propylene oxide surfactant; hexamethyldisiloxane, a polysiloxane, a hydrocarbon surfactant, and combinations thereof.

[0081] Embodiment 4: the method of embodiment 2 or 3, wherein the miscibility additive further comprises a defoamer.

[0082] Embodiment 5: the method of embodiment 4, wherein the defoamer is selected from the group consisting of a long chain alcohol, a silica, and a siloxane.

[0083] Embodiment 6: the method of any of embodiments 1 to 5, wherein the first refrigerant lubricant is selected from the group consisting of a polyalkyl glycol, a polyester oil, a polyvinyl ether, and combinations thereof.

[0084] Embodiment 7: the method of any of embodiments 1 to 6, wherein the incorporating is at an amount, by weight, in the range of about 4% to about 25% miscibility additive to about 75% to about 96% first refrigerant lubricant.

[0085] Embodiment 8: the method of any of embodiments 1 to 7, wherein the conditions comprise mixing.

[0086] Embodiment 9: the method of embodiment 8, wherein the mixing occurs in a non-grinding mill.

[0087] Embodiment 10: the method of embodiment 9, wherein the non-grinding mill is selected from the group consisting of a roller mill without a roller, a ball grinder without a ball, and an attrition mill without a milling medium.

[0088] Embodiment 11 : the method of embodiment 9 or 10, wherein the mixing includes operating the non-grinding mill at a speed of about 100 revolutions-per-minute or less.

[0089] Embodiment 12: the method of any of embodiments 1 to 11 , wherein the incorporating comprises passing the additive mixture through a mesh screen.

[0090] Embodiment 13: the method of embodiment 12, wherein the mesh screen has a mesh size of 200 or greater.TS0112-W001

[0091] Embodiment 14: the method of any of embodiments 1 to 13 further comprising confirming the low foam generation by visual inspection of the additive mixture.

[0092] Embodiment 15: the method of any of embodiments 1 to 14 further comprising measuring the low foam generation by placing at least a portion of the additive mixture in a graduated cylinder.

[0093] Embodiment 16: the method of claim 15, wherein the low foam generation as measured in the graduated cylinder is 5% foam or less, by volume of a liquid portion of the additive mixture.

[0094] Embodiment 17: the method of any of embodiments 1 to 16, wherein the conditions form the additive mixture with low moisture addition.

[0095] Embodiment 18: the method of embodiment 17, wherein the conditions comprise contacting the additive mixture to molecular sieves.

[0096] Embodiment 19: the method of embodiment 18, wherein the molecular sieves comprise a zeolite.

[0097] Embodiment 20: the method of any of embodiments 1 to 19 further comprising combining the additive mixture with a low global warming potential refrigerant.

[0098] Embodiment 21 : the method of embodiment 20, wherein the combining further comprises injecting the additive mixture into an air conditioning system with the low global warming potential refrigerant.

[0099] Embodiment 22: the method of embodiment 21 , wherein the injecting is of an amount, by weight, in the range of about 20% to about 50% low GWP refrigerant and about 50% to about 80% additive mixture.

[0100] Embodiment 23: the method of any of embodiments 1 to 19 further comprising combining the additive mixture with a second refrigerant lubricant.

[0101] Embodiment 24: the method of embodiment 23, wherein the second refrigerant lubricant comprises a polyalkyl glycol.TS0112-W001

[0102] Embodiment 25: the method of any of embodiments 1 to 19 further comprising introducing the additive mixture into an air conditioning system.

[0103] Embodiment 26: the method of embodiment 25, wherein the introducing comprises injecting the additive mixture by hand into the air conditioning system.

[0104] Embodiment 27: the method of embodiment 25 or 26, wherein the additive mixture combines with a second refrigerant lubricant in the air conditioning system to form a lubrication composition miscible with a low global warming potential refrigerant.

[0105] Embodiment 28: a method comprising fully incorporating a miscibility additive comprising a surfactant into a refrigerant lubricant with a non-grinding mill to form an additive mixture with low foam generation.

[0106] Embodiment 29: the method of embodiment 28, wherein the non-grinding mill is selected from the group consisting of a roller mill without a roller, a ball grinder without a ball, and an attrition mill without a milling medium.

[0107] Embodiment 30: the method of embodiment 28 or 29, wherein the mixing includes operating the non-grinding mill at a speed of about 100 revolutions-per-minute or less.

[0108] Embodiment 31 : the method of any of embodiments 28 to 30 further comprising confirming the low foam generation by visual inspection of the additive mixture.

[0109] Embodiment 32: the method of any of embodiments 28 to 30 further comprising measuring the low foam generation by placing at least a portion of the additive mixture in a graduated cylinder.

[0110] As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus. Further, unless expressly stated to the contrary, “or”TS0112-W001 refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).

[0111] The transitional phrase “consisting of” excludes any element, step, or ingredient not specified. If in the claim such would close the claim to the inclusion of materials other than those recited except for impurities ordinarily associated therewith. When the phrase “consists of’ appears in a clause of the body of a claim, rather than immediately following the preamble, it limits only the element set forth in that clause; other elements are not excluded from the claim as a whole.

[0112] The transitional phrase “consisting essentially of” is used to define a composition, method that includes materials, steps, features, components, or elements, in addition to those literally disclosed provided that these additional included materials, steps, features, components, or elements do not materially affect the basic and novel characteristic(s) of the claimed invention, especially the mode of action to achieve the desired result of any of the processes of the present invention. The term “consisting essentially of” occupies a middle ground between “comprising” and “consisting of’.

[0113] Where applicants have defined an invention or a portion thereof with an open- ended term such as “comprising”, it should be readily understood that (unless otherwise stated) the description should be interpreted to also include such an invention using the terms “consisting essentially of” or “consisting of’.

[0114] Also, use of “a” or “an” are employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

[0115] Although certain aspects, embodiments, and principals have been described above, it is understood that this description is made only way of example and not as limitation of the scope of the invention or appended claims.

Claims

TS0112-W001CLAIMSWhat is claimed is:1 . A method comprising incorporating a miscibility additive into a first refrigerant lubricant to form an additive mixture under conditions that produce low foam generation.

2. The method of claim 1 , wherein the miscibility additive comprises a surfactant.

3. The method of claim 2, wherein the surfactant is selected from the group consisting of a primary alcohol ethoxylate surfactant, a secondary alcohol ethoxylate surfactant, a block copolymer of ethylene oxide and propylene oxide surfactant; hexamethyldisiloxane, a polysiloxane, a hydrocarbon surfactant, and combinations thereof.

4. The method of claim 2 or 3, wherein the miscibility additive further comprises a defoamer.

5. The method of claim 4, wherein the defoamer is selected from the group consisting of a long chain alcohol, a silica, and a siloxane.

6. The method of any of claims 1 to 5, wherein the first refrigerant lubricant is selected from the group consisting of a polyalkyl glycol, a polyester oil, a polyvinyl ether, and combinations thereof.

7. The method of any of claims 1 to 6, wherein the incorporating is at an amount, by weight, in the range of about 4% to about 25% miscibility additive to about 75% to about 96% first refrigerant lubricant.

8. The method of any of claims 1 to 7, wherein the conditions comprise mixing.

9. The method of claim 8, wherein the mixing occurs in a non-grinding mill.

10. The method of claim 9, wherein the non-grinding mill is selected from the group consisting of a roller mill without a roller, a ball grinder without a ball, and an attrition mill without a milling medium.11 . The method of claim 9 or 10, wherein the mixing includes operating the nongrinding mill at a speed of about 100 revolutions-per-m inute or less.TS0112-W00112. The method of any of claims 1 to 11 , wherein the incorporating comprises passing the additive mixture through a mesh screen.

13. The method of claim 12, wherein the mesh screen has a mesh size of 200 or greater.

14. The method of any of claims 1 to 13 further comprising confirming the low foam generation by visual inspection of the additive mixture.

15. The method of any of claims 1 to 14 further comprising measuring the low foam generation by placing at least a portion of the additive mixture in a graduated cylinder.

16. The method of claim 15, wherein the low foam generation as measured in the graduated cylinder is 5% foam or less, by volume of a liquid portion of the additive mixture.

17. The method of any of claims 1 to 16, wherein the conditions form the additive mixture with low moisture addition.

18. The method of claim 17, wherein the conditions comprise contacting the additive mixture to molecular sieves.

19. The method of claim 18, wherein the molecular sieves comprise a zeolite.

20. The method of any of claims 1 to 19 further comprising combining the additive mixture with a low global warming potential refrigerant.21 . The method of claim 20, wherein the combining further comprises injecting the additive mixture into an air conditioning system with the low global warming potential refrigerant.

22. The method of claim 21 , wherein the injecting is of an amount, by weight, in the range of about 20% to about 50% low GWP refrigerant and about 50% to about 80% additive mixture.

23. The method of any of claims 1 to 19 further comprising combining the additive mixture with a second refrigerant lubricant.TS0112-W00124. The method of claim 23, wherein the second refrigerant lubricant comprises a polyalkyl glycol.

25. The method of any of claims 1 to 19 further comprising introducing the additive mixture into an air conditioning system.

26. The method of claim 25, wherein the introducing comprises injecting the additive mixture by hand into the air conditioning system.

27. The method of claim 25 or 26, wherein the additive mixture combines with a second refrigerant lubricant in the air conditioning system to form a lubrication composition miscible with a low global warming potential refrigerant.

28. A method comprising fully incorporating a miscibility additive comprising a surfactant into a refrigerant lubricant with a non-grinding mill to form an additive mixture with low foam generation.

29. The method of claim 28, wherein the non-grinding mill is selected from the group consisting of a roller mill without a roller, a ball grinder without a ball, and an attrition mill without a milling medium.

30. The method of claim 28 or 29, wherein the mixing includes operating the nongrinding mill at a speed of about 100 revolutions-per-m inute or less.31 . The method of any of claims 28 to 30 further comprising confirming the low foam generation by visual inspection of the additive mixture.

32. The method of any of claims 28 to 30 further comprising measuring the low foam generation by placing at least a portion of the additive mixture in a graduated cylinder.

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