Low electrical conductivity heat transfer fluid

Abstract

A heat transfer fluid or thermal management system fluid comprising a freezing point depressant, water having an electrical conductivity of less than 5 μS / cm, and one or more electrically non-conductive, low-electrical-conductivity corrosion inhibitors, or a corrosion inhibitor composition comprising one or more organic acids and one or more organic bases, wherein the electrical conductivity of the heat transfer fluid is about 500 μS / cm or less.

Description

[Technical Field]

[0001]

[0001] This application claims priority to U.S. Patent Application No. 63 / 450506, filed on 7 March 2023, the entire contents of which are incorporated herein by reference.

[0002] This document describes effective heat transfer fluids for use as thermal management fluids in electric vehicles. [Background technology]

[0002]

[0003] Heat transfer fluids are essential for the normal operation of automobiles. In conventional automobiles powered by internal combustion engines (ICE), glycol-water-based heat transfer fluids are used in the cooling system to provide long-term, year-round protection. Some requirements for heat transfer fluids are to provide efficient heat transfer to control and maintain engine temperature for efficient fuel efficiency and lubrication, to prevent engine failure due to freezing, boiling, or overheating, and to provide effective heat transfer to meet the requirements of cabin air conditioning and windshield defrosting. A desired additional requirement for heat transfer fluids is to effectively protect all metals in the cooling system from corrosion under a wide range of temperature and operating conditions, ensuring that it performs all of its design functions. An ideal heat transfer fluid used in the cooling system of an automobile powered by an internal combustion engine typically has the following desirable characteristics or properties:

[0003] 1. High heat capacity (or high specific heat) and high thermal conductivity 2. Fluidity within the operating temperature range 3. Low viscosity 4. Low freezing point 5. High boiling point 6. It is compatible with the materials used in the cooling system, can provide good corrosion protection for the metals used in the system, and does not cause degradation of non-metallic materials. 7. Chemically stable within the operating temperature range and under operating conditions. 8. Tendency towards low foaming 9. Low flammability, high flash point 10. Non-toxic or low-toxicity, and odorless. 11. High cost efficiency and sufficient supply

[0004]

[0004] Furthermore, it is desirable to have a distinct color in order for the heat transfer fluid to provide identification and to prevent confusion with other functional fluids and different heat transfer fluid technologies used in automobiles. Such coloring also aims to provide information regarding the concentration of the heat transfer fluid and to enable recognition of the heat transfer fluid during and after use in a cooling system.

[0005]

[0005] No single material has yet been identified that has the best available values for all the desirable properties for use as a heat transfer fluid in an automotive cooling system. Nevertheless, since the early 1960s, in the United States, in ICE engine cooling systems, a 50% ethylene glycol - 50% water-based engine coolant has been adopted as the year-round heat transfer fluid factory-filled by automobile manufacturers. Automobile manufacturers use a 50% ethylene glycol - 50% water-based engine coolant as the factory-filled fluid in order to provide an acceptable balance of available performance characteristics with respect to heat transfer, freeze and boil prevention, flammability, toxicity, availability, prevention of metal corrosion, and compatibility with other materials used in the cooling system.

[0006]

[0006] In recent years, due to the need to reduce exhaust gas emissions during automobile operation, improve energy efficiency, and reduce dependence on oil, electric vehicles have been attracting increasing attention from consumers and manufacturers. Generally, there are four types of electric vehicles available in the market. They are as follows.

[0007] 1. Battery Electric Vehicle (BEV) - Propelled by only electric drive. The energy required to run the vehicle is supplied by a high-voltage battery that is recharged from the outside.

[0008] 2. Hybrid Electric Vehicle (HEV) - Powered by a combination of an internal combustion engine and electric drive. The electric motor is powered by a high-voltage battery, which is charged in-vehicle, for example, through regenerative braking, to increase efficiency. The battery of an HEV cannot be recharged from an external power source.

[0009] 3. Plug-in Hybrid Electric Vehicles (PHEVs) - Plug-in hybrids also use a high-voltage battery to power an electric motor and drive the vehicle, and can be recharged from an external power source, but to enable a longer driving range, they incorporate a smaller internal combustion engine (or, in some models, a direct drive to the wheels) that can recharge the battery.

[0010] 4. Fuel Cell Electric Vehicles (FCEVs) - These vehicles are propelled solely by electric power. FCEVs generate electricity to drive electric motors through a highly efficient electrochemical process within a fuel cell stack. In the fuel cell stack, the oxidation reaction of hydrogen (i.e., fuel) occurs at the anode, and the reduction reaction of oxygen (supplied from air) occurs at the cathode.

[0011]

[0007] The main components of the electric vehicle drive system include the following: 1. High-voltage battery equipped with a control unit for battery control and charging, 2. Electric motor / generator with electronic control (power electronics) and cooling system, 3. Transmission including differential, 4. Brake system (including regenerative braking), and 5. High-voltage air conditioning for in-vehicle climate control

[0012]

[0008] Compared to battery-powered EVs, fuel cell-powered electric vehicles also have additional components such as fuel cell stacks and high-pressure hydrogen storage tanks.

[0013]

[0009] Generally, electric vehicles may have the following drive combinations:

[0014] [Table 1]

[0015]

[0010] Common components of various drive combinations in electric vehicles are electric motors, power electronics, and high-voltage batteries. The thermal management requirements of system components often differ significantly. For example, lithium-ion batteries are commonly used in electric vehicles. At low temperatures (e.g., below zero degrees Celsius), the chemical reactions occurring within the battery slow down, resulting in a significant decrease in performance and range. At high temperatures (e.g., above approximately 40 degrees Celsius), the battery degrades rapidly. Power electronics, on the other hand, cannot operate for extended periods at temperatures above 70-80 degrees Celsius without a significant reduction in lifespan.

[0016]

[0011] Furthermore, the preferred operating temperature of the coolant differs in various components of electric vehicle (EV) drive systems, as listed below. 1. High-voltage lithium-ion battery: 25°C to 35°C or ambient temperature 2. Power Electronics: 60℃~80℃ 3. Electric motor: Maximum 100℃ 4. Fuel cell stack: Approximately 80°C 5. Internal combustion engine: 95℃~120℃

[0017]

[0012] Because the various components have different operating temperature requirements, electric vehicles typically require one more thermal management fluid circuit than usual.

[0018]

[0013] Effective thermal management of lithium-ion batteries (commonly used in EVs as high-voltage batteries for driving or propulsion) is particularly important because it not only affects the driving range of EVs but also plays a crucial role in how quickly the batteries can be recharged at charging stations. Furthermore, effective thermal management also contributes to extending the lifespan of lithium-ion batteries.

[0019]

[0014] The vast majority of electric vehicles currently on the road use ethylene glycol-water-based heat transfer fluids to meet their thermal management needs. Some EV models, such as the Nissan Leaf, also use air cooling for their high-voltage lithium-ion drive battery systems. Using air as a heat transfer fluid simplifies the structure of the cooling system. However, because air has a low thermal capacity and thermal conductivity, air cooling is not an effective solution compared to liquid cooling. Air cooling typically requires 2 to 3 times more energy to remove heat compared to liquid cooling. Uniformly and effectively cooling all cells in an EV battery pack, which may contain a large number of individual cells, is extremely difficult when using air as a heat transfer medium.

[0020]

[0015] On the other hand, most ethylene glycol-water heat transfer fluids currently used as thermal management fluids contain corrosion inhibitors and other components that can ionize in aqueous solutions. Therefore, these ethylene glycol-water heat transfer fluids typically have high electrical conductivity in the range of several thousand μS / cm. These heat transfer fluids are designed to circulate inside cooling plates located adjacent to or near lithium-ion battery cells, but are electrically isolated from high-voltage batteries under normal operating conditions.

[0021]

[0016] Fuel cells are a clean and efficient power source. Fuel cells have been proposed for use in many applications, including as an alternative to the internal combustion engines currently used in automobiles. A fuel cell assembly includes an anode (a negatively charged electrode where the oxidation reaction of the fuel takes place), a cathode (a positively charged electrode where the reduction reaction of an oxidant, such as oxygen, takes place), and an electrolyte between the two electrodes. To generate enough power for use as an automobile engine, a fuel cell-based engine needs to have a large number of cells connected in series to form a fuel cell stack. Each single cell operates at a voltage of approximately 0.6 to 1.0 V DC. Fuel cell stacks proposed for use in automobiles often have more than 100 cells connected in series. Therefore, the DC voltage across the entire fuel cell stack can be very high. The cell voltages commonly reported in automotive fuel cell stacks range from about 125 V DC to 450 V DC.

[0022]

[0017] In fuel cell stack cooling systems of fuel cell-powered vehicles, the coolant in the fuel cell stack flow path may be exposed to DC voltages of up to several volts per centimeter. To minimize stray current corrosion and prevent short circuits of current, electrically nonconductive ethylene glycol-water heat transfer fluids are specified for use in fuel cell stack cooling systems. Furthermore, ion exchange filters containing mixed-bed ion exchange resins are often installed in the circulation paths of fuel cell stack cooling systems to remove ion species from the coolant and prevent the electrical conductivity of the coolant from rising beyond the maximum permissible limit due to glycol degradation or elution of ion species from the surfaces of cooling system components in contact with the coolant.

[0023]

[0018] In addition to generating electricity, the fuel cell assembly also generates heat due to the exothermic nature of the electrochemical reactions involved and the flow of current. Therefore, the fuel cell stack includes coolant lines for circulating coolant to remove heat from the stack. By circulating coolant through the coolant lines, the temperature of the fuel cell stack can be controlled to a desirable range for optimal operating conditions.

[0024]

[0019] However, the cooling system surrounding the fuel cell stack is exposed to the same voltage as the fuel cell stack itself. To prevent or minimize the risk of electric shock, it is desirable to provide a coolant with low conductivity. For example, the upper limit of the electrical conductivity of the coolant may be set to less than 5 μS / cm. Low electrical conductivity of the fuel cell coolant is desirable to reduce shunt current in the cooling system and to minimize the decrease in system efficiency.

[0025]

[0020] Furthermore, fuel cell cooling systems have many metallic components. Stainless steel, aluminum, brass and brazed alloys, as well as other ferrous or non-ferrous alloys, are some of the metals that may be included in fuel cell cooling systems. Among the common industrial alloys available, magnesium alloys have the best strength-to-weight ratio. The use of magnesium alloys in automobiles is increasing due to the need for improved fuel efficiency, reduced pollution, and reduced reliance on petroleum. Recently, several new applications have been developed in various parts of vehicles, including oil pans in certain Honda models, gearbox housings in VW Passat, and radiator support assemblies in the new 2004 model of the Ford F150 truck. However, the use of Mg alloys in vehicle powertrain systems such as engine blocks has been fairly limited so far. One factor limiting the application of Mg alloys in powertrain systems is their poor corrosion resistance, which is particularly noticeable when in contact with water / glycol-based coolants commonly used in vehicle cooling systems. Galvanic corrosion between magnesium alloys and other less reactive (i.e., more noble) alloys is a major cause of excessive corrosion of magnesium alloys in vehicle cooling systems.

[0026]

[0021] Magnesium and the other metals mentioned above can corrode under typical operating conditions. Therefore, corrosion inhibitors must be used in the fuel cell coolant to minimize corrosion and extend the life of the system. However, most known corrosion inhibitors are ionic species (e.g., silicates, nitrites, molybdates, nitrates, carboxylates, phosphates, and borates), and when present at sufficiently high concentrations, as is typically used to provide corrosion protection in engine cooling systems, they would significantly exceed the electrical conductivity limits of the fuel cell coolant. Thus, providing effective corrosion protection to metals, especially more corrosive metals, such as carbon steel, aluminum alloys, magnesium alloys, and yellow metals, in fuel cell cooling systems is a major challenge. The ability to protect these metals from corrosion in the cooling systems of fuel cell-powered vehicles would allow for the use of lower-cost materials in the system, contributing to a reduction in the manufacturing cost of fuel cell-powered vehicles.

[0027]

[0022] In the cooling (or thermal management) systems of the majority of hybrid and BEV vehicles, the corrosion inhibitor formulations currently used in water / glycol-based coolants contain high concentrations of ionic species, such as silicates and carboxylates (C4-C4). 18 These contain mono- or dicarboxylates, benzoates, etc., molybdates, nitrates, phosphates, phosphonates, borates, etc., and provide corrosion protection for various metals in cooling systems. While many of these corrosion-resistant coolants can provide satisfactory corrosion protection for metallic components (including aluminum, cast iron, steel, copper, brass, solder, etc.) used in vehicle cooling systems, such as the thermal management systems of many electric vehicles, the electrical conductivity of these water / glycol-based coolants is usually very high, generally in the range of >1500 μS / cm for most ready-to-use, pre-diluted (e.g., 50 vol. coolant + 50 vol. water) coolant products.

[0028]

[0023] To reduce the risk of lithium-ion battery fires caused by coolant leaks due to accidents (or other reasons), some original equipment manufacturers (OEMs) have begun using pre-diluted, ready-to-use low-electrical conductivity (i.e., less than 150 μS / cm) ethylene glycol-water-based coolants in some models of battery-powered electric vehicles for use in the electric vehicle battery pack cooling system and other cooling systems. However, the corrosion protection performance of these low-electrical conductivity ethylene glycol-water-based coolant products or thermal system management fluids generally has considerable room for improvement, particularly with respect to corrosion protection of corrosive metals commonly used in many vehicle cooling systems, such as aluminum alloys, carbon steel, and cast iron. Furthermore, under the operating conditions of electric vehicle thermal management systems, the corrosion protection performance of these ethylene glycol-water-based coolant products on aluminum alloy surfaces of automotive heat exchangers manufactured in controlled atmosphere brazing processes has considerable room for improvement.

[0029]

[0024] In addition to providing effective corrosion protection, the heat transfer fluid must possess several other properties in order to fulfill its design function. Such desirable properties include, but are not limited to, high heat transfer capacity, freeze protection, boiling protection, corrosion protection, and anti-foaming properties. [Overview of the Initiative] [Means for solving the problem]

[0030]

[0025] After considerable research, the inventors have discovered a novel glycol-water-based heat transfer fluid or heat management fluid composition that has low electrical conductivity, can meet the requirements for effective heat transfer, has excellent protection against corrosion of metals used in cooling systems, prevents freezing and boiling, and has a low foaming tendency.

[0031]

[0026] Aspects and embodiments of the present invention are described in the appended claims. These, as well as other aspects and embodiments of the present invention, are also described herein.

[0027] The heat transfer fluid or thermal management fluid composition described may be provided as a concentrate that can be diluted for subsequent use, or as a pre-diluted, ready-to-use heat transfer fluid or thermal management fluid. When provided as a concentrate, the heat transfer fluid or thermal management fluid contains a freezing point depressant, deionized water having an electrical conductivity of less than 5 μS / cm, and a low-electrically-conductive synergistic corrosion inhibitor formulation that can provide effective corrosion protection of aluminum alloy surfaces in the presence of potassium fluroaluminate flux residue under the operating conditions of an electric vehicle thermal management system. The electrical conductivity of the heat transfer fluid concentrate is less than about 500 μS / cm. When the heat transfer fluid or thermal management fluid is provided as a ready-to-use product, the electrical conductivity of a 50 vol% ready-to-use heat transfer fluid prepared by adding deionized water to the heat transfer fluid concentrate is also less than about 500 μS / cm. The low electrical conductivity of the described heat transfer fluid or thermal management fluid reduces the galvanic corrosion tendency of metals used in the system, including magnesium alloys.

[0032]

[0028] A method according to this teaching for preventing corrosion in a heat transfer system includes bringing at least a portion of the heat transfer system into contact with the heat transfer fluid described.

[0029] In some embodiments, the heat transfer fluid described is silicate, nitride, nitrate, molybdate, carboxylate (for example, but not limited to C4-C4). 18 It does not contain mono- or dicarboxylates (benzoates), phosphates, phosphonates, or borates.

[0033]

[0030] As used herein, references to heat transfer fluids may also refer to thermal management system fluids, whether or not they are explicitly stated. In other words, the absence of an explicit mention of thermal management system fluids when referring to heat transfer fluids does not mean that the compositions described are suitable only for heat transfer fluids. Those skilled in the art will understand that, unless otherwise stated, the compositions described may be suitable for both heat transfer fluids and thermal management system fluids.

[0034]

[0031] In this specification and in the appended claims, the following definitions shall be understood:

[0032] The term “heteroatom” refers to any atom other than carbon and hydrogen. Typical examples of heteroatoms according to this teaching include, but are not limited to, nitrogen, oxygen, and sulfur.

[0035]

[0033] The term "alkyl" refers to a substituted or unsubstituted linear, branched or cyclic hydrocarbon chain containing 1 to 24 carbon atoms in some embodiments. Typical examples of unsubstituted alkyl groups according to this teaching include, but are not limited to, methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, isobutyl, tert-butyl, sec-butyl, cyclobutyl, pentyl, cyclopentyl, hexyl, and cyclohexyl.

[0036]

[0034] The term "alkenyl" refers to a substituted or unsubstituted linear, branched or cyclic unsaturated hydrocarbon chain containing at least one double bond and, in some embodiments, 2 to 24 carbon atoms. Representative unsubstituted alkenyl groups according to this teaching include, but are not limited to, ethenyl or vinyl (-CH=CH2), 1-propenyl, 2-propenyl or allyl (-CH2-CH=CH2), 1,3-butadienyl (-CH=CHCH=CH2), 1-butenyl (-CH=CHCH2CH3), hexenyl, pentenyl, and 1,3,5-hexatrienyl. In some embodiments, the cycloalkenyl group has 5 to 8 carbon atoms and at least one double bond. Representative cycloalkenyl groups that conform to this instruction include, but are not limited to, cyclohexadienyl, cyclohexenyl, cyclopentenyl, cycloheptenyl, cyclooctenyl, cyclohexadienyl, cycloheptadienyl, and cyclooctatrienyl.

[0037]

[0035] The term "alkoxy" refers to a substituted or unsubstituted -O-alkyl group. Representative unsubstituted alkoxy groups according to this instruction include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, and tert-butoxy.

[0038]

[0036] The terms "siloxy" and "silyloxy" refer to a silicon-substituted oxygen group. The silicon-containing portion of the siloxy group may be substituted or unsubstituted. Representative siloxy groups that conform to this teaching include, but are not limited to, trimethylsiloxy (-OSi(CH3)3), triethylsiloxy (-OSi(CH2CH3)3), triisopropylsiloxy (-OSi(i-Pr)3), and tert-butyidimethylsiloxy (-OSi(tert-Bu)(CH3)2).

[0039]

[0037] The term "alkynyl" refers to a substituted or unsubstituted, linear, branched or cyclic unsaturated hydrocarbon chain comprising at least one triple bond and, in some embodiments, 2 to 20 carbon atoms.

[0040]

[0038] The term "aryl" refers to a monocyclic, bicyclic, or polycyclic aromatic ring system of 4 to 20 carbon atoms, whether substituted or unsubstituted. Representative aryl groups according to this teaching include, but are not limited to, benzene, substituted benzenes (e.g., toluene, xylene, styrene), naphthalene, anthracene, and biphenyl.

[0041]

[0039] The term "amino" refers to an unsubstituted or substituted amino (-NH2) group. Amines are primary (-NH2), secondary (-NH2) a ), or third class (-NR) a R b , where R a and R b These may be the same or different. Representative substituted amino groups that conform to this instruction include, but are not limited to, methylamino, dimethylamino, ethylamino, diethylamino, 2-propylamino, 1-propylamino, di(n-propyl)amino, di(isopropyl)amino, methyl-n-propylamino, and tert-butylamino.

[0042]

[0040] The term "halogen" refers to fluorine, chlorine, iodine, or bromine.

[0041] The term “heterocyclic” refers to a saturated, partially unsaturated, or aromatic cyclic system containing 3 to 24 carbon atoms (in some embodiments, 4 to 22 carbon atoms; in other embodiments, 6 to 20 carbon atoms) and at least one heteroatom (in some embodiments, 1 to 3 heteroatoms). The ring may be substituted with one or more substituents. Furthermore, the ring may be monocyclic, bicyclic, or polycyclic. As used herein, the term “heterocyclic” encompasses the term “heteroaryl.” Representative heteroatoms included in the ring include, but are not limited to, nitrogen, oxygen, and sulfur.Representative heterocyclic groups that conform to this instruction include, but are not limited to, aziridine, azirine, oxirane, oxilen, thiirane, thiirane, diazirine, oxaziridine, dioxirane, azetidine, azete, oxetane, oxetane, thiete, thiete, diazetidine, dioxetane, dioxetane, dithiete, pyrrolidine, tetrahydrofuran, thiolane, imidazolidine, pyrazolidene, oxazolidine, i Soxazolidine, thiazolidinedione, isothiazolidene, dioxolane, dithiolane, furazan, oxadiazole, dithiazole, tetrazole, piperidine, oxane, pyran, thian, thiopyran, piperazine, diazine, morpholine, oxazine, thiomorpholine, thian, dioxane, dioxin, dithian, dithian, trioxane, trithian, tetrazine, azepan, azepine, oxepane, oxepin , thiepan, thiepin, homopiperazine, diazepine, thiazepine, azocan, azosin, acridine, benzatiazolin, benzimidazole, benzofuran, benzothiapen, benzothiazole, benzothiophenyl, carbazole, cinnoline, furan, imidazole, 1H-indazole, indole, isoindole, isoquinoline, isothiazole, oxazole, isoxazole, oxadiazole (example) Examples include 1,2,3-oxadiazole, phenazine, phenothiazine, phenoxazine, phthalazine, pteridine, purine, pyrazine, pyrazole, pyridazine, pyridine, pyrimidine, pyrrole, quinazoline, quinoline, quinoxaline, thiazole, thiadiazole (e.g., 1,3,4-thiadiazole), thiophene, triazine (e.g., 1,3,5-triazine), and triazole (e.g., 1,2,3-triazole).

[0043]

[0042] The term "substituted" refers to one or more substituents optionally attached to a backbone structure (e.g., an alkyl backbone, an alkenyl backbone, a heterocyclic backbone, etc.). Representative substituents used in accordance with the present teachings include, but are not limited to, a hydroxyl group, an amino group (-NH2, -NHR a , -NR a R b ), an oxy group (-O-), a carbonyl group (-CO-), a thiol group, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a halo group, a nitrile group, a nitro group, an aryl group, and a heterocyclic group. These substituents may be further substituted with 1 to 3 substituents. Examples of substituted substituents include, but are not limited to, carboxamide, alkyl mercapto, alkyl sulfonyl, alkyl amino, dialkyl amino, carboxylate, alkoxycarbonyl, alkyl aryl, aralkyl, alkyl heterocycle, heterocyclic aryl, and haloalkyl. The substituents should not chemically substantially interfere with the reactions of the present invention (e.g., cause cross-reactions with reactants or stop the reaction, etc.).

[0044]

[0043] The phrase "fuel cell" refers to any type of fuel cell, e.g., but not limited to, a polymer electrolyte membrane (PEM) fuel cell, a direct methanol fuel cell, an alkaline fuel cell, a phosphoric acid fuel cell, a molten carbonate fuel cell, a solid oxide fuel cell, and any combination thereof. Further, the phrase "fuel cell" as used herein includes one or more individual fuel cells and "stacks" (i.e., electrically connected combinations) of one or more individual fuel cells.

[0045]

[0044] It should be understood that the elements and features of the various representative embodiments described below can be combined in different ways to create new embodiments, and they are likewise within the scope of the present teachings.

[0046]

[0045] Unless otherwise explicitly stated, all percentages in the present disclosure refer to weight percentages.

[0046] The present invention extends substantially to compositions and methods described herein and / or shown with reference to the accompanying drawings. The present invention extends to any novel embodiments or features described herein and / or illustrated. Furthermore, embodiments of compositions can be applied to embodiments of methods and vice versa. Furthermore, any, some, and / or all features in one embodiment can be applied in any suitable combination to any, some, and / or all features in any other embodiment. It should also be understood that certain combinations of the various features described and defined in any embodiment of the present invention can be carried out and / or supplied and / or used independently.

[0047]

[0047] The embodiments described above and many of the associated advantages of the present technology will be more readily understood by referring to the following description when read in conjunction with the attached drawings. [Brief explanation of the drawing]

[0048] [Figure 1]

[0048] This is a diagram showing a product list of alkoxylated alcohols available from TOMAH Products, Inc. [Figure 2A]

[0049] This figure shows photographs of the front side (the side with the identification number stamped before the test) of five metal test specimens after being tested in a modified ASTM D1384-24 test (test time: 336 hours at 88°C), in which a pre-diluted, ready-to-use, very low-electrical-conductivity original equipment (OE) BEV battery system thermal management fluid 1 (sometimes also called OE BEV coolant 1) was used as the test solution without any addition of corrosive salts, as further described in Comparative Example 6 below. [Figure 2B]

[0050] Figure 2A shows photographs of the backs of five metal test specimens after being tested in a modified ASTM D1384-24 test (test duration: 336 hours at 88°C), in which a pre-diluted, ready-to-use, very low electrical conductivity OE BEV battery system thermal management fluid 1 (sometimes also called OE BEV coolant 1) was used as the test solution without any addition of corrosive salts, as further described in Comparative Example 6 below. [Figure 3A]

[0051] This figure shows photographs of the front side of five metal test specimens after being tested in a modified ASTM D1384-24 test (test duration: 336 hours at 88°C). In this test, a pre-diluted, ready-to-use low electrical conductivity OE BEV battery system (also specified for use in hybrid EV inverter systems) thermal management fluid 2 (sometimes also called OE BEV coolant 2) was used as the test solution without any addition of corrosive salts, as further described in Comparative Example 7 below. [Figure 3B]

[0052] Figure 3A shows photographs of the backs of the five metal test specimens after being tested in a modified ASTM D1384-24 test (test duration: 336 hours at 88°C). In this test, a pre-diluted, ready-to-use, low-electrical-conductivity OE BEV battery system (also specified for use in hybrid EV inverter systems) thermal management fluid 2 (sometimes called OE BEV coolant 2) was used as the test solution without any addition of corrosive salts, as further described in Comparative Example 7 below. [Figure 4A]

[0053] This figure shows photographs of the front side of five metal test specimens after being tested in a modified ASTM D1384-24 test (test duration: 336 hours at 88°C). In this test, a pre-diluted, ready-to-use, moderately electrically conductive battery system thermal management fluid (sometimes called aftermarket EV coolant) was used as the test solution without any addition of corrosive salts, as further described in Comparative Example 8 below. [Figure 4B]

[0054] This figure shows photographs of the backs of the five metal test specimens in Figure 4A after being tested in a modified ASTM D1384-24 test (test duration: 336 hours at 88°C). In this test, a pre-diluted, ready-to-use, moderately electrically conductive battery system thermal management fluid (sometimes called aftermarket EV coolant) was used as the test solution without any addition of corrosive salts, as further described in Comparative Example 8 below. [Figure 5]

[0055] The graph below shows the measured anodic polarization curves obtained on the surface of a CAB heat exchanger covered with potassium fluoroaluminate flux residue, using the heat transfer fluid compositions described in Tables 1, 8, 12, and 131. The measurements were performed using AgAgCl in a 3M NaCl solution as a reference electrode at a scanning speed of 1 mV / sec. [Figure 6]

[0056] The graph below shows the measured anodic polarization curves obtained on the surface of a CAB heat exchanger covered with potassium fluoroaluminate flux residue, using the heat transfer fluid compositions listed in Table 11. The measurements were performed using AgAgCl in a 3M NaCl solution as a reference electrode at a scanning speed of 1 mV / second. [Modes for carrying out the invention]

[0049]

[0057] According to one embodiment, a low-electrically conductive or electrically non-conductive heat transfer fluid, whether provided in the form of a concentrated liquid or a pre-diluted, ready-to-use heat transfer fluid, has an electrical conductivity of less than about 500 μS / cm and may have an electrical conductivity of about 1 μS / cm to about 500 μS / cm, or about 1 μS / cm to about 250 μS / cm, or about 1 μS / cm to about 100 μS / cm.

[0050]

[0058] In some cases, low-electrically conductive or electrically non-conductive heat transfer fluids may contain one or more freezing point depressants, deionized water, one or more neutral phosphate esters, such as tris(2-butoxyethyl) phosphate or other trialkoxyalkyl phosphates, or trialkyl phosphates, and / or one or more neutral alkyl phosphonocarboxylates or alkoxyl phosphonocarboxylates, and other optional components (e.g., one or more azole compounds, polyethylene glycol, polypropylene glycol, carboxylates of C6-C6). 10 The additives may include, but are not limited to, sorbitan carboxylate, which is an aliphatic carboxylate; triethanolamine; electrically non-conductive or low-conductivity defoaming agents; electrically non-conductive or low-conductivity colorants or dyes; and other heat transfer fluid additives, such as surfactants, dispersants, scale inhibitors, biocides, corrosion inhibitors, wettability enhancers, viscosity modifiers, and / or oxygen scavengers, provided that these optional components do not increase the electrical conductivity of the resulting fluid beyond the above-mentioned limits of electrical conductivity.

[0051]

[0059] In other embodiments, the low-electrically conductive or electrically non-conductive heat transfer fluid comprises one or more freezing point depressants, water, one or more neutral phosphate esters, one or more neutral alkyl phosphonocarboxylates or alkoxyl phosphonocarboxylates, one or more alkaline earth metal cations, and azole compounds such as benzotriazole, tolyltriazole, alkylbenzotriazole, tetrahydrobenzotriazole and tetrahydrotolyltriazole, polyalkaline glycols such as polyethylene glycol and polypropylene glycol, sorbitan carboxylate, ethanolamine, diethanolamine, triethanolamine, morpholine, cyclohexylamine, dicyclohexylamine, low-electrically conductive corrosion inhibitors, surfactants, electrically non-conductive or low-electrically conductive defoamers, electrically non-conductive or low-electrically conductive colorants or dyes, and other coolant additives, one or more optional components selected from these.

[0052]

[0060] In some embodiments, the low-electrical-conductivity or electrically non-conductive heat transfer fluid essentially consists of about 25% to about 99.5% by weight of a freezing point depressant or combination of freezing point depressants, about 0.05% to about 80% by weight of deionized water, one or more neutral phosphate esters, one or more neutral alkyl phosphonocarboxylates or alkoxyl phosphonocarboxylates, one or more polyethylene glycols, one or more polypropylene glycols, one or more azole compounds, and other optional components that may include, but are not limited to, sorbitan carboxylates, electrically non-conductive or low-electrical-conductivity defoamers, electrically non-conductive or low-electrical-conductivity colorants or dyes, and / or nonionic surfactants. Low-electrically conductive or electrically non-conductive heat transfer fluids may have an electrical conductivity of less than about 500 μS / cm, or an electrical conductivity of about 1 μS / cm to about 500 μS / cm, or about 1 μS / cm to about 250 μS / cm, or about 1 μS / cm to about 100 μS / cm.

[0053]

[0061] In further embodiments, the low-electrical-conductivity or electrically non-conductive heat transfer fluid comprises one or more freezing point depressants, deionized water or low-electrical-conductivity water, one or more neutral phosphate esters, one or more neutral alkyl phosphonocarboxylates or alkoxyl phosphonocarboxylates, one or more alkaline earth metal carboxylates, one or more polyethylene glycols, one or more polypropylene glycols, one or more azole compounds, and other optional components selected from sorbitan carboxylate, electrically non-conductive or low-electrical-conductivity defoamers, electrically non-conductive or low-electrical-conductivity colorants or dyes, and / or nonionic surfactants.

[0054] Electrical conductivity

[0062] As described above, the heat transfer fluid (whether provided as a concentrate or as a pre-diluted, ready-to-use heat transfer fluid) should have a low electrical conductivity. In this regard, in some embodiments, the electrical conductivity of such a heat transfer fluid should be 500 μS / cm or less. In some cases, the electrical conductivity should be less than 100 μS / cm, less than 50 μS / cm, or less than 10 μS / cm. In some embodiments, the electrical conductivity of the heat transfer fluid concentrate and the ready-to-use heat transfer fluid derived from the heat transfer fluid concentrate (e.g., by dilution with water) in accordance with this teaching may be one of several different values ​​or may fall within one of several different ranges.For example, if the heat transfer fluid concentrate or the prepared heat transfer fluid derived therefrom has the following values: approximately 90 μS / cm, 89 μS / cm, 88 μS / cm, 87 μS / cm, 86 μS / cm, 85 μS / cm, 84 μS / cm, 83 μS / cm, 82 μS / cm, 81 μS / cm, 80 μS / cm, 79 μS / cm, 78 μS / cm, 77 μS / cm, 76 μS / cm, 75 μS / cm, 74 μS / cm, 73 μS / cm, 72 μS / cm, 71μS / cm, 70μS / cm, 69μS / cm, 68μS / cm, 67μS / cm, 66μS / cm, 65μS / cm, 64μS / cm, 63μS / cm, 62μS / cm, 61μS / cm, 60μS / cm, 59μS / cm, 58μS / cm, 57μS / cm, 56μS / cm, 55μS / cm, 54μS / cm, 53μS / cm, 52μS / cm, 51μS / cm, 50μS / cm, 49μS / cm, 48μ S / cm, 47μS / cm, 46μS / cm, 45μS / cm, 44μS / cm, 43μS / cm, 42μS / cm, 41μS / cm, 40μS / cm, 39μS / cm, 38μS / cm, 37μS / cm, 3 6μS / cm, 35μS / cm, 34μS / cm, 33μS / cm, 32μS / cm, 31μS / cm, 30μS / cm, 29μS / cm, 28μS / cm, 27μS / cm, 26μS / cm, 25μS / cm, Having an electrical conductivity of one or less of the following values ​​is within the scope of this instruction: 24 μS / cm, 23 μS / cm, 22 μS / cm, 21 μS / cm, 20 μS / cm, 19 μS / cm, 18 μS / cm, 17 μS / cm, 16 μS / cm, 15 μS / cm, 14 μS / cm, 13 μS / cm, 12 μS / cm, 11 μS / cm, 10 μS / cm, 9 μS / cm, 8 μS / cm, 7 μS / cm, 6 μS / cm, or 5 μS / cm.

[0055]

[0063] Furthermore, it is within the scope of this instruction that the electrical conductivity of a heat transfer fluid concentrate or a ready-to-use heat transfer fluid derived therefrom falls within one of several ranges. In the first range group, the electrical conductivity of the heat transfer fluid concentrate and / or a ready-to-use heat transfer fluid derived therefrom falls within the following ranges: approximately 1 μS / cm to 99 μS / cm, 2 μS / cm to 98 μS / cm, 3 μS / cm to 97 μS / cm, 4 μS / cm to 96 μS / cm, 5 μS / cm to 95 μS / cm, 6 μS / cm to 94 μS / cm, 7 μS / cm to 93 μS / cm, 8 μS / cm to 92 μS / cm, 9 μS / cm to 91 μS / cm, 10 μS / cm to 90 μS / cm, and 11 μS / cm. S / cm~89μS / cm, 12μS / cm~88μS / cm, 13μS / cm~87μS / cm, 14μS / cm~86μS / cm, 15μS / cm~85μS / cm, 16μS / cm~84μS / cm, 17μS / cm~83μS / cm, 18μS / cm~82μS / cm, 19μS / cm~81μS / cm, 20μS / cm~80μS / cm, 21μS / cm~79μS / cm, 22μS / cm~78μS / cm, 23μS / cm~77μS / cm, 24μS / c m~76μS / cm, 25μS / cm~75μS / cm, 26μS / cm~74μS / cm, 27μS / cm~73μS / cm, 28μS / cm~72μS / cm, 29μS / cm~71μS / cm, 30μS / cm~70μS / cm , 31μS / cm~69μS / cm, 32μS / cm~68μS / cm, 33μS / cm~67μS / cm, 34μS / cm~66μS / cm, 35μS / cm~65μS / cm, 36μS / cm~64μS / cm, 37μS / cm~6 In the second range group, the electrical conductivity of the heat transfer fluid concentrate and / or the heat transfer fluid prepared for use derived therefrom falls into one of the following ranges: approximately 1 μS / cm to 100 μS / cm, 2 μS / cm to 100 μS / cm,3μS / cm~100μS / cm、4μS / cm~100μS / cm、5μS / cm~100μS / cm、6μS / cm~100μS / cm、7μS / cm~100μS / cm、8μS / cm~100μS / cm、9μS / cm~100μS / cm、10μS / cm~100μS / cm、11μS / cm~100μS / cm、12μS / cm~100μS / cm、13μS / cm~100μS / cm、14μS / cm~100μS / cm、15μS / cm~100μS / cm、16μS / cm~100μS / cm、17μS / cm~100μS / cm、18μS / cm~100μS / cm、19μS / cm~100μS / cm、20μS / cm~100μS / cm、21μS / cm~100μS / cm、22μS / cm~100μS / cm、23μS / cm~100μS / cm、24μS / cm~100μS / cm、25μS / cm~100μS / cm、26μS / cm~100μS / cm、27μS / cm~100μS / cm、28μS / cm~100μS / cm、29μS / cm~100μS / cm、30μS / cm~100μS / cm、31μS / cm~100μS / cm、32μS / cm~100μS / cm、33μS / cm~100μS / cm、34μS / cm~100μS / cm、35μS / cm~100μS / cm、36μS / cm~100μS / cm、37μS / cm~100μS / cm、38μS / cm~100μS / cm、39μS / cm~100μS / cm、40μS / cm~100μS / cm、41μS / cm~100μS / cm、42μS / cm~100μS / cm、43μS / cm~100μS / cm、44μS / cm~100μS / cm、45μS / cm~100μS / cm、46μS / cm~100μS / cm、47μS / cm~100μS / cm、48μS / cm~100μS / cm、49μS / cm~100μS / cm、50μS / cm~100μS / cm、51μS / cm~100μS / cm、52μS / cm~100μS / cm、53μS / cm~100μS / cm、54μS / cm~100μS / cm、55μS / cm~100μS / cm、56μS / cm~100μS / cm、57μS / cm~100μS / cm、58μS / cm~100μS / cm、59μS / cm~100μS / cm、60μS / cm~100μS / cm、61μS / cm~100μS / cm、62μS / cm~100μS / cm, 63μS / cm~100μS / cm, 64μS / cm~100μS / cm, 65μS / cm~100μS / cm, 66μS / cm~100μS / cm, 67μS / cm~100μS / cm, 68μS / cm~100μS / cm, 69μS / cm~100μS / cm, 70μS / cm~100μS / cm, 71μS / cm~100 μS / cm, 72μS / cm~100μS / cm, 73μS / cm~100μS / cm, 74μS / cm~100μS / cm, 75μS / cm~100μS / cm, 76μS / cm~ 100μS / cm, 77μS / cm~100μS / cm, 78μS / cm~100μS / cm, 79μS / cm~100μS / cm, 80μS / cm~100μS / cm, 81μS / c m~100μS / cm, 82μS / cm~100μS / cm, 83μS / cm~100μS / cm, 84μS / cm~100μS / cm, 85μS / cm~100μS / cm, 86μ S / cm~100μS / cm, 87μS / cm~100μS / cm, 88μS / cm~100μS / cm, 89μS / cm~100μS / cm, 90μS / cm~100μS / cm, It falls into one of the following ranges: 91 μS / cm to 100 μS / cm, 92 μS / cm to 100 μS / cm, 93 μS / cm to 100 μS / cm, 94 μS / cm to 100 μS / cm, 95 μS / cm to 100 μS / cm, 96 μS / cm to 100 μS / cm, 97 μS / cm to 100 μS / cm, 98 μS / cm to 100 μS / cm, or 99 μS / cm to 100 μS / cm. In the third range group, the electrical conductivity of the heat transfer fluid concentrate and / or the prepared heat transfer fluid derived therefrom is in the following ranges: 1 μS / cm to 99 μS / cm, 1 μS / cm to 98 μS / cm, 1 μS / cm to 97 μS / cm, 1 μS / cm to 96 μS / cm, 1 μS / cm to 95 μS / cm, 1 μS / cm to 94 μS / cm, 1 μS / cm to 93 μS / cm, 1 μS / cm to 92 μS / cm S / cm, 1μS / cm~91μS / cm, 1μS / cm~90μS / cm, 1μS / cm~89μS / cm, 1μS / cm~88μS / cm, 1μS / cm~87μS / cm, 1μS / c m~86μS / cm, 1μS / cm~85μS / cm, 1μS / cm~84μS / cm, 1μS / cm~83μS / cm, 1μS / cm~82μS / cm, 1μS / cm~81μS / cm,1μS / cm~80μS / cm、1μS / cm~79μS / cm、1μS / cm~78μS / cm、1μS / cm~77μS / cm、1μS / cm~76μS / cm、1μS / cm~75μS / cm、1μS / cm~74μS / cm、1μS / cm~73μS / cm、1μS / cm~72μS / cm、1μS / cm~71μS / cm、1μS / cm~70μS / cm、1μS / cm~69μS / cm、1μS / cm~68μS / cm、1μS / cm~67μS / cm、1μS / cm~66μS / cm、1μS / cm~65μS / cm、1μS / cm~64μS / cm、1μS / cm~63μS / cm、1μS / cm~62μS / cm、1μS / cm~61μS / cm、1μS / cm~60μS / cm、1μS / cm~59μS / cm、1μS / cm~58μS / cm、1μS / cm~57μS / cm、1μS / cm~56μS / cm、1μS / cm~55μS / cm、1μS / cm~54μS / cm、1μS / cm~53μS / cm、1μS / cm~52μS / cm、1μS / cm~51μS / cm、1μS / cm~50μS / cm、1μS / cm~49μS / cm、1μS / cm~48μS / cm、1μS / cm~47μS / cm、1μS / cm~46μS / cm、1μS / cm~45μS / cm、1μS / cm~44μS / cm、1μS / cm~43μS / cm、1μS / cm~42μS / cm、1μS / cm~41μS / cm、1μS / cm~40μS / cm、1μS / cm~39μS / cm、1μS / cm~38μS / cm、1μS / cm~37μS / cm、1μS / cm~36μS / cm、1μS / cm~35μS / cm、1μS / cm~34μS / cm、1μS / cm~33μS / cm、1μS / cm~32μS / cm、1μS / cm~31μS / cm、1μS / cm~30μS / cm、1μS / cm~29μS / cm、1μS / cm~28μS / cm、1μS / cm~27μS / cm、1μS / cm~26μS / cm、1μS / cm~25μS / cm、1μS / cm~24μS / cm、1μS / cm~23μS / cm、1μS / cm~22μS / cm、1μS / cm~21μS / cm、1μS / cm~20μS / cm、1μS / cm~19μS / cm、1μS / cm~18μS / cm、1μS / cm~17μS / cm、1μS / cm~16μS / cm、1μS / cm~15μS / cm、It falls into one of the following ranges: 1 μS / cm to 14 μS / cm, 1 μS / cm to 13 μS / cm, 1 μS / cm to 12 μS / cm, 1 μS / cm to 11 μS / cm, 1 μS / cm to 10 μS / cm, 1 μS / cm to 9 μS / cm, 1 μS / cm to 8 μS / cm, 1 μS / cm to 7 μS / cm, 1 μS / cm to 6 μS / cm, or 1 μS / cm to 5 μS / cm.

[0056]

[0064] In some embodiments, during vehicle operation, a pre-treated ion exchange resin may be used to maintain the electrical conductivity of the coolant at a low level, for example, within the above-mentioned level, while preventing the depletion of corrosion inhibitors from the heat transfer fluid and maintaining fluid color identification.

[0057] Coagulation point depressants

[0065] Suitable freezing point depressants include alcohols or mixtures of alcohols, such as monohydric or polyhydric alcohols and mixtures thereof. The alcohols may be selected from the group consisting of methanol, ethanol, propanol, butanol, furfurol, furfuryl alcohol, tetrahydrofurfuryl alcohol, ethoxylated furfuryl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, dipropylene glycol, butylene glycol, glycerol, glycerin, glycerol-1,2-dimethyl ether, glycerol-1,3-dimethyl ether, glycerol monoethyl ether, sorbitol, 1,2,6-hexanetriol, trimethylpropane, methoxyethanol, and other alkoxy alkanols, and mixtures thereof. In some embodiments, the freezing point depressant may contain one or more of the alcohols described, and the composition is intended to not contain or exclude one or more of the other alcohols described.

[0058]

[0066] The freezing point depressant may be present in amounts of approximately 10% to 99.9% by weight, or approximately 15%, 20%, 30%, 40%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, or approximately 99.9%. In some cases, the freezing point depressant may be present in a range where the lower limit is one of approximately 15%, 20%, 30%, 40%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85%, while the upper limit is one of approximately 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, or approximately 99.9%.

[0059] water

[0067] Water suitable for use as the heat transfer fluid described has a low electrical conductivity, for example, 5 μS / cm or less. In this regard, the heat transfer fluid may be provided by deionized water or desalinated water having a low electrical conductivity, i.e., an electrical conductivity of 5 μS / cm or less. In some cases, water has an electrical conductivity of approximately 0.01 μS / cm to 5 μS / cm, or approximately 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.6, 4.8, 4.9, or approximately 5 μS / cm, or any range that can be formed from the aforementioned values.

[0060]

[0068] Water may be present in the heat transfer composition in amounts of about 0.1% to about 90% or about 0.5% to 70% by weight, or about 1% to about 60% by weight. In some cases, water may be present in amounts of about 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, or any amount that can be formed from the aforementioned values. Those skilled in the art will understand that when the heat transfer fluid described is formulated as a concentrate, the amount of water present is significantly less than when it is formulated as a pre-diluted, ready-to-use heat transfer fluid.

[0061] Corrosion inhibitor raw materials and compositions

[0069] As noted above, fuel cell coolant systems have many metallic components for which corrosion protection is desired. At the same time, suitable corrosion inhibitors and compositions should have sufficiently low conductivity so that the conductivity of the heat transfer fluid described is within the limits described. For this purpose, those skilled in the art will understand that corrosion inhibitors that are electrically nonconductive or have low electrical conductivity may be useful in the heat transfer fluid described. Furthermore, conductive corrosion inhibitors, i.e., those having a positive charge (e.g., an acid) or a negative charge (e.g., a base), may be provided in appropriate concentrations so that the conductivity of the heat transfer fluid described is within the limits described. In addition, or instead, conductive corrosion inhibitors may be provided as inhibitor compositions containing two or more compounds such that the inhibitor composition has a generally neutral pH and / or is electrically nonconductive or has low electrical conductivity.

[0062]

[0070] Suitable electrically non-conductive or low-conductivity corrosion inhibitors may include one or more neutral phosphate esters, such as tris(2-butoxyethyl) phosphate, trialkoxyalkyl phosphate, trialkyl phosphate, and mixtures thereof. Alternatively, one or more azole compounds, such as benzotriazole, tetrahydrotolyltriazole, and tolyltriazole, or mixtures thereof.

[0063]

[0071] Other suitable neutral phosphate compounds that can be used in combination with or without the above-mentioned one or more neutral phosphate esters include, but are not limited to, neutral alkyl or alkoxyl phosphonocarboxylates in which the alkyl or alkoxy group may contain 1 to 5 carbon atoms. Exemplary compounds include, but are not limited to, triethyl phosphonoformate, triethyl phosphonoacetate, trimethyl phosphonoacetate, methyl diethyl phosphonoacetate, triethyl 2-phosphonopriopionate, triethyl-3-phosphonopropionate, trimethyl-3-phosphonopropionate, and mixtures thereof.

[0064]

[0072] Generally, one or more electrically non-conductive or low-conductivity corrosion inhibitors may be present in the heat transfer fluid in amounts ranging from about 0.01% to about 10%, or about 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 3.0%, 4.0%, 5.0%, 6.0%, 7.0%, 8.0%, 9.0%, about 10.0%, or any amount that can be formed from the aforementioned values.

[0065]

[0073] In some cases, corrosion inhibitor compositions used in heat transfer (or thermal management system) fluids may contain one or more low concentrations of soluble alkaline earth metals (selected from calcium, magnesium, or strontium) or zinc compounds, or mixtures thereof. The soluble alkaline earth metals or zinc compounds may include oxides, hydroxides, nitrates, nitrites, or other soluble metal salts, or mixtures thereof. Low concentrations of such compounds can provide optimal corrosion protection for iron-based and aluminum alloys in cooling or thermal management systems. The term "soluble" means that the compound can dissolve in the freezing point depressant / water heat transfer fluid at a level suitable for use in the fluid, whether in fluid concentrate form or in ready-to-use / pre-diluted form, and that the compound can ionize in the heat transfer fluid concentrate and / or ready-to-use (pre-diluted with deionized water) fluid to produce the corresponding metal ions.

[0066]

[0074] Alternatively, oxides and hydroxides of alkaline earth metals (Ca, Mg, Sr) or lithium can be provided in combination with an acid to reduce the electrical conductivity of a mixture of alkaline earth metals (Ca, Mg, Sr) or lithium oxides and hydroxides with an acid. Those skilled in the art will understand what constitutes a suitable acid. One example, but not limited to, is benzoic acid.

[0067]

[0075] Other soluble alkaline earth metals or alkali metal compounds may include calcium salts, magnesium salts, and lithium salts formed between calcium, magnesium, and lithium ions and phosphonates or phosphinates, for example, calcium-PBTC salts (where PBTC is 2-phosphonobutane-1,2,4-tricarboxylic acid), calcium-HEDP salts (where HEDP is 1-hydroxyethane-1,1-diphosphonic acid), calcium-HPA salts (where HPA is hydroxyphosphonoacetic acid or 2-hydroxyphosphonoacetic acid), calcium phosphonosuccinates, calcium-PSO salts (where PSO is a mixture of mono, bis, and oligomeric phosphonosuccinate additions, and / or similar compounds, and combinations thereof).

[0068]

[0076] Soluble alkaline earth metals (selected from calcium, magnesium, or strontium) or zinc compounds, or mixtures thereof, may be present in the heat transfer fluid at low concentrations. For example, when present in the heat transfer fluid, soluble alkaline earth metals may be present in amounts ranging from about 0.001% to about 0.15% by weight, or from 0.01% to about 0.05% by weight, or any range that can be formed from the aforementioned values.

[0069]

[0077] Other optional corrosion inhibitors suitable for use in the corrosion inhibitor compositions, and therefore suitable for use in the heat transfer fluids described, may include siloxane compounds. Exemplary suitable siloxane compounds include Silwet siloxane surfactants from Momentive Performance Materials Inc. (Niskayuna, NY 12309) or other suppliers, such as Silwet L-77, Silwet L-7657, Silwet L-7650, Silwet L-7608, Silwet L-7210 and Silwet L-7220, as well as other Silwet surfactants, or other similar siloxane-polyether copolymers available from Dow Corning or other suppliers.

[0070]

[0078] Other suitable siloxane compounds include non-conductive or nearly non-conductive organosilane compounds containing one or more silicon-carbon bonds (i.e., compounds that can be hydrolyzed in the presence of water to form silanols (i.e., compounds having one or more Si-OH groups)), such as alkoxysilanes, e.g., Formasil 891, Formasil 593, Formasil 433, Silquest® Y-5560 silane (i.e., polyalkylene oxide alkoxysilane), and Silquest® A-186 [2-(3,4 [Epoxycyclohexyl)ethyltrimethoxysilane], Silquest® A-187 (3-glycidoxypropyltrimethoxysilane), 3-aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, octyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, methyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, isobutyltrimethoxysilane, phenyltrimethoxysilane, methyltrimethoxysilane, or other Silquest surfactants available from GE Silicones / OSI Specialties / Momentive Performance Materials or other suppliers. It is also intended that the heat transfer fluid may not contain siloxane compounds, including the compounds described in detail above.

[0071]

[0079] Siloxane compounds and mixtures thereof may be present in the heat transfer fluid in amounts of about 0.01% to about 10% by weight, and in some cases, in amounts of about 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, or about 9%, or any range that can be formed from the aforementioned values, for example, but not limited to, amounts in the range of about 0.02% to about 2%.

[0072]

[0080] In some embodiments, the corrosion inhibitor composition, and therefore the heat transfer fluid, may contain corrosion inhibitors for copper and copper alloys. Suitable copper and copper corrosion inhibitors, though not limited to those described above, include compounds containing a five-membered or six-membered heterocycle as an active functional group, where the heterocycle contains at least one nitrogen atom, such as azole compounds. In particular, benzotriazoles, tolyltriazoles, methylbenzotriazoles (e.g., 4-methylbenzotriazole and 5-methylbenzotriazole), butylbenzotriazoles, and other alkylbenzotriazoles (e.g., alkyl groups containing 2 to 20 carbon atoms), mercaptobenzothiazoles, thiazoles and other substituted thiazoles, imidazoles, benzimidazoles and other substituted imidazoles, indazoles and substituted indazoles, tetrazoles and substituted tetrazoles, tetrahydrotolyltriazoles, and mixtures thereof can be used as corrosion inhibitors for copper and copper alloys. It is also intended that the heat transfer fluid may not contain azole compounds, including those described in detail above.

[0073]

[0081] If present, copper and copper alloy corrosion inhibitors may be present in the heat transfer fluid composition in an amount of about 0.01 to about 4% by weight. In some cases, copper and copper alloy corrosion inhibitors may be present in an amount of about 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 1%, 2%, or about 3%, or any range that can be formed from the aforementioned values.

[0074]

[0082] In some embodiments, the corrosion inhibitor composition, and therefore the heat transfer fluid (or thermal management system fluid), is polyethylene glycol, polypropylene glycol, and carboxylate C6-C6. 10The fluid may contain one or more optional corrosion inhibitors selected from aliphatic carboxylates such as sorbitan carboxylate (e.g., sorbitan caprylate or sorbitan monooctanoate, sorbitan monoheptanoate, sorbitan monohexanoate, sorbitan monononanoate, sorbitan monodecanoate), triethanolamine, other amines, and mixtures thereof. It is also intended that the heat transfer fluid (or thermal management system fluid) may not contain these described optional corrosion inhibitors.

[0075]

[0083] If present, the optional corrosion inhibitors mentioned above may be present in amounts ranging from approximately 0.05% by weight to approximately 4.0% by weight.

[0084] In some embodiments, the corrosion inhibitor composition, and therefore the heat transfer fluid, may contain a nonionic surfactant as a corrosion inhibitor. Typical nonionic surfactants suitable for use in accordance with this teaching may include fatty acid esters such as sorbitan fatty acid esters, alkoxylated alcohols, polyalkylene glycols, polyalkylene glycol esters, copolymers of ethylene oxide (EO) and propylene oxide (PO), polyoxyalkylene derivatives of sorbitan fatty acid esters, and mixtures thereof. While we do not wish to be bound by any particular theory and do not intend to limit in any way the scope of the attached claims or their equivalents, it is currently believed that alkoxylated alcohols used in accordance with this teaching may remain in the solution without being consumed or decomposed in the heat transfer fluid under operating conditions, thereby providing a strong defoaming effect to the heat transfer fluid. In some embodiments, the average molecular weight of additional nonionic surfactants optionally used in accordance with this teaching is between about 55 and about 300,000, and in some embodiments, between about 110 and about 10,000. Furthermore, any of the nonionic surfactants described below, including those described in detail below, may be excluded from the heat transfer composition; that is, the heat transfer fluid may not contain any of the nonionic surfactants described below.

[0076]

[0085] Typical sorbitan fatty acid esters include C5 and C 10 Aliphatic carboxylates include, for example, sorbitan caprylate or sorbitan monooctanoate, sorbitan monoheptanoate, sorbitan monohexanoate, and sorbitan monononanoate. Suitable sorbitan fatty acid esters include sorbitan monolaurate (e.g., sold under the trademark names Span® 20, Arlacel® 20, and S-MAZ® 20M1), sorbitan monopalmitate (e.g., Span® 40 or Arlacel® 40), sorbitan monostearate (e.g., Span® 60, Arlacel® 60, or S-MAZ® 60K), and sorbitan monooleate (e.g., For example, Span(registered trademark) 80 or Arlacel(registered trademark) 80), sorbitan monosesquioleate (e.g., Span(registered trademark) 83 or Arlacel(registered trademark) 83), sorbitan trioleate (e.g., Span(registered trademark) 85 or Arlacel(registered trademark) 85), sorbitan tridtearate (e.g., S-MAZ(registered trademark) 65K), and sorbitan monotolate (e.g., S-MAZ(registered trademark) 90) may also be mentioned.

[0077]

[0086] Representative alkoxylated alcohols suitable for optional use as additional nonionic surfactants in accordance with this instruction include, but are not limited to, ethoxylated alcohols, propoxylated alcohols, and / or similar substances, and combinations thereof.

[0078]

[0087] In some embodiments, the ethoxylated alcohol used optionally in accordance with this teaching is of the following formula: RO(CH2CH2O) n H (I) (In the formula, R is a linear primary alcohol, and n is the total number of moles of ethylene oxide.) It can be expressed as follows.

[0079]

[0088] In other embodiments, the propoxylated alcohol used optionally in accordance with this teaching is of the following formula: RO(CH2CH2CH2O) m H (II) (In the formula, R is a linear primary alcohol, and m is the total number of moles of propylene oxide.) It can be expressed as follows.

[0080]

[0089] In further embodiments, the alkoxylated alcohol used optionally in accordance with this teaching is of the following formula: RO(CH2CH2O) j (CH2CH2CH2O) k H (III) (In the formula, R is a linear primary alcohol, j is the total number of moles of ethylene oxide, and k is the total number of moles of propylene oxide.) It can be expressed as follows.

[0081]

[0090] In some embodiments, in each of formulas (I) to (III), the linear primary alcohol may contain 4 to 25 carbon atoms, 6 to 15 carbon atoms, or 7 to 12 carbon atoms. Furthermore, "n" and "m" are integers with values ​​between 1 and 15 (inclusive). The values ​​of j and k are integers between 0 and 15 (inclusive), and j+k is 1 or greater.

[0082]

[0091] Typical commercially available alkoxylated alcohols can be obtained from many suppliers, such as The Dow Chemical Company (Midland, MI), BASF Corporation (Mount Olive, NJ or Florham Park, NJ), and Tomah Products, Inc. (Milton, WI). An example of an alkoxylated alcohol product suitable for optional use as an additional nonionic surfactant in accordance with this instruction is TRITON® EF-19 surfactant (>98% alcohol, C8-C) available from Dow Chemical Co. 10 , ethoxylated propoxylated (CAS number 88603-25-8), MACOL® LF 110 surfactant (alkoxylated alcohol), and Plurafac* SLF18 (100% alcohol, C6~C 10Examples include ethoxylated propoxylated alcohols (CAS number: 68987-81-5). Other suitable alkoxylated alcohols available from TOMAH Products, Inc. are shown in Figure 1. Additional examples of alkoxylated alcohol products suitable for optional use as additional nonionic surfactants according to this teaching may include the low-foaming nonionic surfactants of the Plurafac® LF type available from BASF. Plurafac® LF type surfactants are alkoxylated and consist mainly of unbranched aliphatic alcohols containing higher alkene oxides in combination with ethylene oxide. Suitable Plurafac® LF type surfactants for optional use include Plurafac® LF120, Plurafac® LF131, Plurafac® LF132, Plurafac® LF220, Plurafac® LF221, Plurafac® LF223, Plurafac® LF224, Plurafac® LF231, Plurafac® LF300, Plurafac® LF301, Plurafac® LF303, Plurafac® LF305, and Plurafac® LF305. Examples include fac(registered trademark)LF400, Plurafac(registered trademark)LF401, Plurafac(registered trademark)LF403, Plurafac(registered trademark)LF404, Plurafac(registered trademark)LF405, Plurafac(registered trademark)LF431, Plurafac(registered trademark)LF500, Plurafac(registered trademark)LF600, Plurafac(registered trademark)LF711, Plurafac(registered trademark)LF7319, Plurafac(registered trademark)LF900, Plurafac(registered trademark)LF901, Plurafac(registered trademark)LF1300, and Plurafac(registered trademark)LF1433.

[0083]

[0092] Suitable polyalkylene glycols include polyethylene glycol, polypropylene glycol, and mixtures thereof. Examples of polyethylene glycols suitable for use include CARBOWAX® polyethylene glycol and methoxy polyethylene glycol from Dow Chemical Company (e.g., CARBOWAX PEG200, 300, 400, 600, 900, 1000, 1450, 3350, 4000, and 8000, etc.) or PLURACOL® polyethylene glycol from BASF Corp. (e.g., Pluracol® E200, 300, 400, 600, 1000, 2000, 3350, 4000, 6000, and 8000, etc.). Suitable polyalkylene glycol esters include monoesters and diesters of various fatty acids, such as MAPEG® polyethylene glycol esters from BASF (e.g., MAPEG® 200ML or PEG200 monolaurate, MAPEG® 400DO or PEG400 dioleate, MAPEG® 400MO or PEG400 monooleate, and MAPEG® 600DO or PEG600 dioleate). Suitable copolymers of ethylene oxide (EO) and propylene oxide (PO) include various Pluronic and Pluronic® block copolymer surfactants from BASF, DOWFAX nonionic surfactants from DOW Chemical, UCON® fluids, and SYNALOX lubricants.Suitable polyoxyalkylene derivatives of sorbitan fatty acid esters include polyoxyethylene 20 sorbitan monolaurate (e.g., products sold under the trade names TWEEN® 20 or T-MAZ20), polyoxyethylene 4 sorbitan monolaurate (e.g., TWEEN® 21), polyoxyethylene 20 sorbitan monopalmitate (e.g., TWEEN® 40), polyoxyethylene 20 sorbitan monostearate (e.g., TWEEN® 60), and Examples include T-MAZ60K, polyoxyethylene 20-sorbitan monooleate (e.g., TWEEN® 80 or T-MAZ80), polyoxyethylene 20-tristearate (e.g., TWEEN® 65 or T-MAZ65K), polyoxyethylene 5-sorbitan monooleate (e.g., TWEEN® 81 or T-MAZ81), and polyoxyethylene 20-sorbitan trioleate (e.g., TWEEN® 85 or T-MAZ85K).

[0084]

[0093] Representative copolymers of ethylene oxide (EO) and propylene oxide (PO) that can be optionally used as additional nonionic surfactants in accordance with this instruction include, but are not limited to, various Pluronic and Pluronic R block copolymer surfactants from BASF, DOWFAX nonionic surfactants from DOW Chemical, UCON® fluids and SYNALOX lubricants, and / or similar products, and combinations thereof.

[0085]

[0094] Representative polyoxyalkylene derivatives of sorbitan fatty acid esters that can be optionally used as additional nonionic surfactants in accordance with this instruction include, but are not limited to, polyoxyethylene 20-sorbitan monolaurate (e.g., products sold under the trade names TWEEN® 20 or T-MAZ20), polyoxyethylene 4-sorbitan monolaurate (e.g., TWEEN® 21), polyoxyethylene 20-sorbitan monopalmitate (e.g., TWEEN® 40), and polyoxyethylene 20-sorbitan monostearate (e.g., TWEEN Examples include (registered trademark) 60 or T-MAZ60K), polyoxyethylene 20-sorbitan monooleate (e.g., TWEEN® 80 or T-MAZ80), polyoxyethylene 20-tristearate (e.g., TWEEN® 65 or T-MAZ65K), polyoxyethylene 5-sorbitanomonoleate (e.g., TWEEN® 81 or T-MAZ81), polyoxyethylene 20-sorbitan trioleate (e.g., TWEEN® 85 or T-MAZ85K), and / or similar materials, and combinations thereof.

[0086]

[0095] In embodiments of the heat transfer concentrate containing one or more additional nonionic surfactants, the concentration of each of the one or more additional nonionic surfactants may vary depending on the application. In some embodiments, each of the one or more additional nonionic surfactants may be present in the composition in an amount of about 1 ppm to about 3% by weight, or about 5 ppm to about 1.5% or about 10 ppm to about 1% by weight, based on the total weight of the heat transfer fluid concentrate. Within this range, the one or more additional nonionic surfactants may be present in an amount of about 0.9% by weight or less, about 0.8% by weight or less in some embodiments, about 0.7% by weight or less in some embodiments, about 0.6% by weight or less in some embodiments, and about 0.5% by weight or less in some embodiments, based on the total weight of the heat transfer fluid concentrate.

[0087]

[0096] As described above, it may be useful to provide a corrosion inhibitor composition, which may, in some cases, contain one or more organic acids and one or more organic bases such that the inhibitor composition has a generally neutral pH and / or is electrically nonconductive or has low electrical conductivity.

[0088]

[0097] With the above in mind, the corrosion inhibitor composition may contain one or more of the following organic bases in combination with an organic acid in order to provide a neutral or nearly neutral pH composition.

[0089]

[0098] Organic bases suitable for use in the low-electrically conductive heat transfer fluids disclosed in this application are compounds that yield a pH greater than 7 when dissolved in deionized water, i.e., compounds that yield a pH greater than 7.0 at room temperature. Generally, in the low-electrically conductive heat transfer fluids disclosed in this application, one or more organic base components are used to increase the pre-alkalinity of the fluid (determined according to ASTM D1121). pK of organic base (B) suitable for use in water b It is less than 7.0 at 25℃. Corresponding conjugate acid (BH + ) pK a The value is higher than 7.0 in water at room temperature.

[0090]

[0099] Organic bases may be used to neutralize acidic components such as carboxylic acids, phosphonic acids, phosphinic acids, and acidic non-neutral phosphate esters that may be present in low-electrically conductive heat transfer fluids, thereby maintaining the resulting electrical conductivity at a low level, i.e., within the parameters described. In some cases, one or more organic bases may be included in the low-electrically conductive heat transfer fluid to increase the preliminary alkalinity level and maintain the pH of the prepared heat transfer fluid at a desired level, even if no acidic components are present in the fresh heat transfer fluid composition.

[0091]

[0100] With the above in mind, in some embodiments, representative organic bases suitable for use in this application may include mono, di, and trialcanolamines (or hydroxyalkylamines) containing 2 to 18 carbon atoms, such as ethanolamine, propanolamine, butanolamine (or 4-hydroxybutylamine), isobutanolamine (i.e., 2-amino, 2-methyl, 1-propanol), diethanolamine, triethanolamine, mono, di, and triisopropanolamines, octyldiethanolamine, diethylethanolamine, dimethylisopropanolamine, and 5-aminopentanol. In some embodiments, suitable organic bases may include heterocyclic compounds, such as pyrrolidine, morpholine, imidazole, benzimidazole, 1,2,3-triazole, imidazoline, imidazolidine, and piperidine. In some embodiments, representative organic bases suitable for use may include aliphatic, cyclic aliphatic, or aromatic amines having 2 to 18 carbon atoms. In some embodiments, suitable organic bases for use may include amino acids, such as histidine, lysine, and arginine.

[0092]

[0101] Other exemplary organic bases include amine salts of cyclohexenecarboxylate compounds derived from tall oil fatty acids, amine compounds such as mono, di, and triethanolamines, morpholine, benzylamine, cyclohexylamine, dicyclohexylamine, hexylamine, AMP (i.e., 2-amino-2-methyl-1-propanol or isobutanolamine), DEAE (i.e., diethylethanolamine), DEHA (i.e., diethylhydroxylamine), DMAE (i.e., 2-dimethylaminoethanol), DMAP (i.e., dimethylamino-2-propanol), and MOPA (i.e., 3-methoxypropylamine), triethanolamine, triisopropanolamine, and other amines. Other suitable amine compounds include, but are not limited to, ethanolamine, diethanolamine, morpholine, benzylamine, cyclohexylamine, dicyclohexylamine, hexylamine, AMP (2-amino-2-methyl-1-propanol or isobutanolamine), DEAE (diethylethanolamine), DEHA (diethylhydroxylamine), DMAE (2-dimethylaminoethanol), DMAP65 (dimethylamino-2-propanol), MOPA (3-methoxypropylamine), and / or similar compounds, and combinations thereof.

[0093]

[0102] Other organic bases include amino acids, such as arginine, histidine, and lysine. Alternatively, other organic bases include thiazoles and azoles, such as compounds containing a 5-membered or 6-membered heterocycle as an active functional group, the heterocycle containing at least one nitrogen atom. Exemplary compounds include benzotriazole, tolyltriazole, methylbenzotriazole (e.g., 4-methylbenzotriazole and 5-methylbenzotriazole), butylbenzotriazole, and other alkylbenzotriazoles (e.g., alkyl groups containing 2 to 20 carbon atoms), mercaptobenzothiazole, thiazole and other substituted thiazoles, imidazole, benzimidazole and other substituted imidazoles, indazole and substituted indazole, tetrazole and substituted tetrazole, tetrahydrotolyltriazole, and mixtures thereof.

[0094]

[0103] Furthermore, the heat transfer fluids described may also exclude one or more of the organic bases described, including but not limited to amine compounds, amino acids, azoles, and thiazole compounds.

[0095]

[0104] Examples of organic acids, though not limited to these, include octanoic acid, decanoic acid, non-neutral phosphate esters, phosphonates (e.g., 2-butane-1,2,4-tricarboxylic acid and octylphosphonic acid), and phosphinates. Other suitable organic acids include C6-C6. 24 Examples include mono, di, and tricarboxylic acids, which include aliphatic and aromatic mono, di, and tricarboxylic acids (both linear and possibly branched).

[0096]

[0105] Further suitable organic acids may include organophosphates (also known as phosphate esters). In some embodiments, the organophosphate used in accordance with this teaching has the following structure (1):

[0097] [ka]

[0098] (In the formula, R 1 , R 2 , and R 3 Each of these is independently a site that is either hydrogen, an optionally substituted heteroatom-containing alkyl, an optionally substituted heteroatom-containing alkenyl, an optionally substituted carbonyl-containing alkyl, an optionally substituted carbonyl-containing alkenyl, or an optionally substituted site selected from the group consisting of alkyl, alkenyl, aryl, phosphono, phosphino, alkylamino, amino, and combinations thereof. It has the R group of the organic phosphate (i.e., R 1 , R e , and / or R 3 In some embodiments in which the ) contains one or more heteroatoms, the one or more heteroatoms may form an ether bond (e.g., -COC-), a sulfide bond (-CSC-), an amino bond (-CNC), or a combination thereof.

[0099]

[0106] Typical organic phosphates used in accordance with this instruction include, but are not limited to, ethylene glycol phosphate; 1,2,3-propanetriol phosphate (CAS No.: 12040-65-2); polyether phosphate; C6-C 12 Alkyl alcohol ethoxylate phosphate (CAS No.: 68921-24-4); alkali metal salts of cresyl ethoxylate phosphate esters (CAS No.: 66057-30-5); potassium cresyl phosphate (CAS No.: 37281-48-4); octylphenoxy polyethoxyethyl phosphate; octylphenoxy polyethyl phosphate; olyethylene glycol mono(octylphenyl) ether phosphate; formula R-phenyl (CH2CH2O) x Phosphoric acid (wherein R is hydrogen or C1-C) 20Alkyl (C1~C in some embodiments) e Alkali metal salts of alkylphenoxypolyethoxyethyl phosphate having (where x is 1 to 30 (2 to 10 in some embodiments); alkyl or aryl acid phosphates, e.g., isooctyl acid phosphate, 2-ethylhexyl acid phosphate, amyl acid phosphate, amyl dihydrogen phosphate, diamyl hydrogen phosphate, butyl acid phosphate, and / or similar; and combinations thereof.

[0100] Representative phosphate esters suitable for use in accordance with this instruction are available from many suppliers, including, but are not limited to, Dow Chemical Company (Midland, MI), Stepan Company (Northfield, IL), Solvay SA / Rhodia Inc. (Brussels, Belgium), Ashland Inc. (Covington, KY), Clariant Corporation (Muttenz, Switzerland), PCC Chemax Inc. (Piedmont, SC), IsleChem LLC (Grand Island, NY), and Lakeland Laboratories Limited (Manchester, England).

[0101]

[0107] In some embodiments, the organic phosphate used in accordance with this teaching may be selected from the group consisting of polyether phosphates or alcohol phosphates, which are, but are not limited to, (a) Triton® H-66, Triton® H-55, Triton® QS-44, and / or Triton® XQS-20 surfactants from Dow Chemical Company; (b) potassium salts of Rhodafac® H-66 or cresyl ethoxylate phosphates (CAS No. 66057-30-5), Rhodafac H-66-E or potassium salts of aromatic ethoxylate phosphates, Rhodafac HA-70 or polyoxyethylene phenyl phosphate form (CAS No. 39464-70-5), Rhodafac PA 23 or ethoxylated fatty alcohol phosphates (CAS No. 68585-36-4), and / or Rhodafac LO / 529-E or sodium salt of ethoxylated alkylphenol phosphate (CAS No. 68954-84-7), (c) C6~C from Stepan Company e(d) From PCC Chemax Inc., Chemfac NF-100 (98% polyphosphate, esterified with ethylene glycol, CAS number 68553-96-8) or ethylene glycol phosphate, Chemfac NA-350 or 1,2,3-propanetriol phosphate (CAS number 12040-65-2, as the main component of Chemfac NA-350), Chemfac PB-106K (polyoxyethylene decyl phosphate, potassium salt, or poly(oxy-1,2-ethanediyl), alpha-isodecyl-omega-hydroxy-phosphate, potassium salt, CAS number 68071-17-0), Chemfac PB-184 (POE oleyl phosphate or poly(oxy-1,2-ethanediyl), alpha-9-octadecenyl-omega-hydroxy-(Z)-, phosphate, CAS No. 39464-69-2), Chemfac PF-636 (poly(oxy-1,2-ethanediyl), alpha-hydro-omega-hydroxy, phosphate, CAS No. 9056-42-2), Chemfac PB-264 (POE ether phosphate or poly(oxy-1,2-ethanediyl), alpha-hydro-omega-hydroxy-, mono-C12-14-alkyl ether, phosphate, CAS No. 68511-37-5), Chemfac NC-096 (POE(6) nonylphenol phosphate or poly(oxy-1,2-Ethanediyl), alpha-(nonylphenyl)-omega-hydroxy, branched, phosphate, CAS number 68412-53-3), Chemfac NB-041 (POE aliphatic phosphate ester), Chemfac NB-042 (POE aliphatic phosphate ester), Chemfac 126 (POE aliphatic phosphate ester), Chemfac NB-159 (POE aliphatic phosphate ester), Chemfac NC-006E (POE aliphatic phosphate ester), Chemfac NC-0910 (POE aliphatic phosphate ester), Chemfac PB-082 (POE aliphatic phosphate ester), Chemfac PB-104 (POE aliphatic phosphate ester), Chemfac PB-109, Chemfac PB-133, Chemfac PB-135, Chemfac PB-136, Chemfac (e) Phosphorylated alcohols, e.g., PA100, PA800, PA800K, and PA801 from Lakeland Laboratories Ltd., (f) Phosphorylated alcohol ethoxylates, e.g., PAE802, PAE106, PAE126, PAE136, PAE147, PAE176, PAE185, and PAE1780 from Lakeland Laboratories Ltd., (g) Phosphorylated phenol ethoxylates, e.g., Lakeland Laboratories Ltd. Including PPE604, PPE604K, PPE154, PPE156, PPE159, and PPE1513 from Ltd., (h) and / or similar, and (i) combinations thereof.

[0102]

[0108] In some embodiments, the organic phosphates used in accordance with this teaching include alkyl and aryl acid phosphates. Representative alkyl or aryl acid phosphates that can be used in accordance with this teaching include, but are not limited to, amyl acid phosphate, n-butyl acid phosphate, methyl acid phosphate, phenyl acid phosphate, 2-ethylhexyl acid phosphate, dimethyl acid phosphate, isooctyl acid phosphate, and / or similar, and combinations thereof. Monoalkyl / aryl acid phosphates, dialkyl / aryl acid phosphates, or combinations thereof may also be used in accordance with this teaching.

[0103]

[0109] The amount of organic phosphate may vary depending on the application. For example, the concentration of one or more organic phosphates may be in the range of about 0.0025% by weight to about 10% by weight (e.g., about 0.005% to about 5% by weight, about 0.01% to about 3% by weight, about 0.05% to about 2% by weight, or about 0.05% to about 0.5% by weight) based on the total weight of the heat transfer fluid concentrate. Within this range, the amount may be about 0.005% by weight or more, and in some embodiments, about 0.01% by weight or more. Also within this range, the amount may be about 1% by weight or less, and in some embodiments, about 0.5% by weight or less.

[0104]

[0110] In some cases, the heat transfer raw materials and / or compositions may be phosphonates (e.g., AMP, i.e., aminotrimethylenephosphonic acid; HEDP, i.e., 1-hydroxyethylidene-1,1-diphosphonic acid; HPA, i.e., hydroxyphosphonoacetic acid or 2-hydroxyphosphonoacetic acid; PBTC, i.e., 2-butanephosphono-1,2,4-tricarboxylic acid; octylphosphonic acid, PCAM, i.e., a mixture of phosphonocarboxylate acids; and / or sodium salts of organic phosphonic acids H-[CH(COONa)CH(COONa)]) e -PO3Na2(wherein n<5 and n 平均Examples include Bricorr 288, which is a mixture of (1.4) and other phosphonates, and phosphinates (e.g., PSO, i.e., phosphinic acid oligomers, which are mixtures of mono, bis, and oligomeric phosphinosuccinate adducts and other phosphinates).

[0105]

[0111] Other organic acids include carboxylic acids, e.g., benzoic acid and / or its salts, and n-alkyl monocarboxylic acids and / or their salts, as well as other carboxylates. As used herein, the term “carboxylate” includes carboxylic acids, their salts, and combinations of one or more carboxylic acids and one or more carboxylate salts. Suitable additional carboxylate salts include alkali metal (e.g., lithium, sodium, and potassium) salts and alkaline earth metal (e.g., calcium, magnesium, and strontium) salts. Additional carboxylates may contain one or more carboxyl groups and may be linear or branched. It is expressly intended that combinations of additional carboxylates may be used, and such combinations are encompassed by the terms “carboxylate” and “carboxylic acid.” In some embodiments, the additional carboxylates according to this teaching have 4 to 24 carbon atoms (e.g., 6 to 24 carbon atoms). In other embodiments, the additional carboxylates according to this teaching have 6 to 20 carbon atoms. The additional carboxylates may be aliphatic, aromatic, or a combination of both. In some embodiments, the additional carboxylic acid is a C6-C20 monobasic or dibasic aliphatic or aromatic carboxylic acid and / or its alkali metal salt. In some embodiments, the additional carboxylate according to this teaching consists of carbon, hydrogen, and oxygen and does not contain heteroatoms other than oxygen. Representative aliphatic carboxylates used in accordance with this instruction include, but are not limited to, 2-ethylhexanoic acid, hexanoic acid, heptanoic acid, octanoic acid, neodecanoic acid, decanoic acid, nonanoic acid, isononanoic acid (e.g., 7-methyloctanoic acid, 6,6-dimethylheptonic acid, 3,5,5-trimethylhexanoic acid, 3,4,5-trimethylhexanoic acid, 2,5,5-trimethylhexanoic acid, 2,2,4,4-tetramethylpentanoic acid, and / or similar, and combinations thereof), isoheptanoic acid, dodecanoic acid, sebacic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, dodecanediic acid, and / or similar, and combinations thereof.Representative aromatic carboxylates include, but are not limited to, benzoic acid, toluic acid (methylbenzoic acid), tert-butylbenzoic acid, alkoxybenzoic acid (e.g., methoxybenzoic acid, i.e., o-, p-, or m-anisic acid), salicylic acid, phthalic acid, isophthalic acid, terephthalic acid, phenylacetic acid, mandelic acid, 1,2,4-benzenetricarboxylic acid (or trimellitic acid), 1,3,5-benzenetricarboxylic acid, 1,2,3-benzenetricarboxylic acid (or hemimelittic acid), and / or similar compounds, and combinations thereof.

[0106]

[0112] In some embodiments, the additional carboxylate used in the corrosion inhibitor composition according to this teaching comprises multiple carboxylates. In some embodiments, the additional carboxylates include aliphatic monocarboxylates, aliphatic dicarboxylates, aromatic monocarboxylates, aromatic dicarboxylates, or combinations thereof. In some embodiments, the additional carboxylates comprise one or more C6-C20 carboxylates, each of which is individually selected from the group consisting of aliphatic monocarboxylates, aliphatic dicarboxylates, aromatic monocarboxylates, aromatic dicarboxylic acids, and combinations thereof. In some embodiments, the additional carboxylates comprise at least one additional C6-C20 monobasic or dibasic aliphatic or aromatic carboxylic acid and / or its alkali metal salt. In some embodiments, the additional carboxylates include 2-ethylhexanoic acid, adipic acid, neodecanoic acid, sebacic acid, benzoic acid, p-toluic acid, t-butylbenzoic acid, alkoxybenzoic acid, or combinations thereof.

[0107]

[0113] The concentration of additional carboxylate may vary depending on the application. In some embodiments, the carboxylate is present in an amount of about 0.01% to about 5.0% by weight, based on the total weight of the corrosion inhibitor formulation, and in some embodiments, in an amount of about 0.05% to about 1.5% by weight. Within these ranges, the carboxylate is present in amounts of about 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.4 8%, 0.49%, 0.50%, 0.60%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.70%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, 0.78%, 0.79%, 0.80%, 0.81%, 0.82% It may be present in amounts of 0.83%, 0.84%, 0.85%, 0.86%, 0.87%, 0.88%, 0.89%, 0.90%, 0.91%, 0.92%, 0.93%, 0.94%, 0.95%, 0.96%, 0.97%, 0.98%, 0.99%, 1.00%, 1.10%, 1.20%, 1.30%, 1.40%, or about 1.50%.

[0108]

[0114] In some embodiments, water-soluble polymers suitable for use in corrosion inhibitor formulations according to this teaching are (1) C3~C 16 (2) At least one monomer unit containing monoethylenically unsaturated mono or dicarboxylic acids, or alkali metal salts or ammonium salts thereof, or (2) amides, nitriles, carboxylate esters, acid halides (e.g., acid chlorides), acid anhydrides, and / or similar substances, and combinations thereof, C3-C16 The present invention includes homopolymers, copolymers, terpolymers, and interpolymers having at least one monomer unit containing a monoethylenically unsaturated mono or dicarboxylic acid derivative. In some embodiments, water-soluble polymers suitable for use in accordance with this teaching may contain at least 5% of repeating units of (1) or (2), and in some embodiments, at least 10% of repeating units of (1) or (2).

[0109]

[0115] Representative monocarboxylic acids suitable for use in the production of water-soluble polymers that can be used in corrosion inhibitor compositions according to this instruction include, but are not limited to, acrylic acid, methacrylic acid, ethylacrylic acid, vinyl acetic acid, allyl acetic acid, and crotonic acid.

[0110]

[0116] Representative monocarboxylic acid esters suitable for use in the production of water-soluble polymers that can be used in corrosion inhibitor formulations according to this instruction include, but are not limited to, butyl acrylate, n-hexyl acrylate, tert-butylaminoethyl methacrylate, diethylaminoethyl acrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, methyl acrylate, methyl methacrylate, tertiary butyl acrylate, and vinyl acetate.

[0111]

[0117] Representative dicarboxylic acids suitable for use in the manufacture of water-soluble polymers that may be used in corrosion inhibitor formulations according to this instruction include, but are not limited to, maleic acid, itaconic acid, fumaric acid, citaconic acid, mesaconic acid, and methylenemalonic acid.

[0112] Defoaming agent raw materials and compositions

[0118] The heat transfer fluid (or thermal management system fluid) may contain electrically non-conductive or low-conductivity defoaming material. Suitable defoaming materials include (a) silicones, e.g., products containing SAG10, SAG7133, SAG831, Silbreak320, Silbreak321, Sibreak322, Silbreak329, Silbreak638, octamethylcyclotetrasiloxane, or similar products available from Momentive Performance Materials, Dow Corning or other suppliers; (b) ethylene oxide-propylene oxide (EO-PO) block copolymers, propylene oxide-ethylene oxide-propylene oxide (PO-EP-PO) block copolymers (e.g., Pluronic L61, Pluronic L81, or other Pluronic and Pluronic (c) Products; poly(ethylene oxide), poly(propylene oxide), e.g., PPG2000 (i.e., polypropylene oxide with an average molecular weight of 2000); (c) hydrophobic amorphous silica; (d) polydiorganosiloxane products (e.g., products containing polydimethylsiloxane (PDMS)); organically modified polydimethylsiloxane products; fatty acids; fatty acid esters (e.g., stearic acid); (e) fatty alcohols; alkoxylated alcohols; polyglycols; polyether polyol acetates; polyether ethoxylated sorbital hexaoleates; poly(ethylene oxide-propylene oxide) monoallyl ether acetates; (f) waxes; naphtha; kerosene; aromatic oils; and any one or more of the above exemplary combinations of the aforementioned defoamers. Examples of polydimethylsiloxane emulsion-based antifoamers include PC-5450NF from Performance Chemicals, LLC in Boscawen, NH, and CNC antifoam XD-55NF and XD-56 from CNC International in Woonsocket, RI.

[0113]

[0119] Those skilled in the art will understand that a suitable defoaming agent raw material may include one or more of the nonionic surfactants described above in relation to corrosion inhibitors and compositions. For this purpose, suitable nonionic surfactants for use as defoaming agent raw materials or in defoaming compositions may include, but are not limited to, alkoxy alcohols, including ethoxylated alcohols, propoxylated alcohols, and / or similar alcohols, and combinations thereof.

[0114]

[0120] In some embodiments, the ethoxylated alcohol used optionally in accordance with this teaching is of the following formula: RO(CH2CH2O) n H (I) (In the formula, R is a linear primary alcohol, and n is the total number of moles of ethylene oxide.) It can be expressed as follows.

[0115]

[0121] In other embodiments, the propoxylated alcohol used optionally in accordance with this teaching is of the following formula: RO(CH2CH2CH2O) m H (II) (In the formula, R is a linear primary alcohol, and m is the total number of moles of propylene oxide.) It can be expressed as follows.

[0116]

[0122] In further embodiments, the alkoxylated alcohol used optionally in accordance with this teaching is of the following formula: RO(CH2CH2O) j (CH2CH2CH2O) k H (III) (In the formula, R is a linear primary alcohol, j is the total number of moles of ethylene oxide, and k is the total number of moles of propylene oxide.) It can be expressed as follows.

[0117]

[0123] In some embodiments, in each of formulas (I) to (III), the linear primary alcohol may contain 4 to 25 carbon atoms, or 6 to 15 carbon atoms, or 7 to 12 carbon atoms. Furthermore, "n" and "m" are integers with values ​​between 1 and 15 (inclusive). The values ​​of j and k are integers between 0 and 15 (inclusive), and j+k is 1 or greater.

[0118]

[0124] Typical commercially available alkoxylated alcohols are available from many suppliers, such as The Dow Chemical Company (Midland, MI), BASF Corporation (Mount Olive, NJ or Florham Park, NJ), and Tomah Products, Inc. (Milton, WI). Examples of alkoxylated alcohol products in accordance with this instruction are TERGITOL® XD (alkyl EO / PO copolymer with a molecular weight of 2990) and TRITON® EF-19 surfactant (>98% alcohol, C8-C), both available from Dow Chemical Co. 10 , ethoxylated propoxylated (CAS number 88603-25-8), MACOL® LF110 surfactant (alkoxylated alcohol) and Plurafac® SLF18 (100% alcohol, C6~C 10Examples include ethoxylated propoxylated alcohols (CAS number 68987-81-5). Other suitable alkoxylated alcohols available from TOMAH Products, Inc. are shown in Figure 1. Additional examples of alkoxylated alcohol products may include the low-foaming nonionic surfactants of the Plurafac® LF type, available from BASF. Plurafac® LF type surfactants are alkoxylated, mainly consisting of unbranched fatty alcohols, and contain higher alkene oxides along with ethylene oxide. Plurafac(registered trademark) LF type surfactants include Plurafac(registered trademark) LF120, Plurafac(registered trademark) LF131, Plurafac(registered trademark) LF132, Plurafac(registered trademark) LF220, Plurafac(registered trademark) LF221, Plurafac(registered trademark) LF223, Plurafac(registered trademark) LF224, Plurafac(registered trademark) LF231, Plurafac(registered trademark) LF300, Plurafac(registered trademark) LF301, Plurafac(registered trademark) LF303, Plurafac(registered trademark) LF305, and Plurafac(registered trademark) Examples include Plurafac® LF400, Plurafac® LF401, Plurafac® LF403, Plurafac® LF404, Plurafac® LF405, Plurafac® LF431, Plurafac® LF500, Plurafac® LF600, Plurafac® LF711, Plurafac® LF7319, Plurafac® LF900, Plurafac® LF901, Plurafac® LF1300, and Plurafac® LF1433.

[0119]

[0125] In some cases, the defoaming composition may contain a synergistic combination of an alcohol, a fatty alcohol alkoxylate as described above in relation to formula (III), and an optional alkyl EO / PO copolymer. The defoaming composition may be present in the heat transfer fluid in amounts of about 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or about 1.0%, or any range that can be generated from these values.

[0120]

[0126] In this combination, the alcohol may generally be an alcohol having 1 to 32 carbon atoms and may be linear or branched. In some cases, the alcohol may be an aliphatic alcohol having 2 to 10 carbon atoms, such as ethanol, n-propanol, butanol, isobutanol, pentanol, isopentanol, neopentanol, hexanol and its isomers, heptanol and its isomers, octanol and its isomers, nonanol and its isomers, decanol and its isomers. In this regard, the defoaming composition may contain alcohol in amounts of about 70% to about 90%, or about 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, or about 90%, or any range that can be produced from these values.

[0121]

[0127] Fatty alcohol alkoxylates may be present in the antifoaming composition in amounts of about 10% to about 30%, or in amounts of about 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or about 30%, or any range that can be generated from these values.

[0122]

[0128] Alkyl EO / PO copolymers, if present, may be present in the antifoaming composition in amounts of about 0.1% to 2.0%, or about 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, or about 2.0%, or any amount that can be generated from these values.

[0123]

[0129] Furthermore, it is intended that the heat transfer fluid composition described herein be particularly excluded from the presence of any one of the defoaming agents described herein. Selective raw materials

[0130] The heat transfer fluid (or thermal management system fluid) may contain one or more electrically non-conductive or low-conductivity coolant additives, such as colorants, dispersants and scale inhibitors, wetting agents, and other additives. Optionally, it may also contain tetraalkyl orthosilicate esters having alkyl groups containing 1 to 20 carbon atoms (e.g., tetramethyl orthosilicate, tetraethyl orthosilicate, etc.). If present, the tetraalkyl orthosilicate ester may be present in the heat transfer fluid formulation in an amount of 0.001% to about 5% by weight (and may also be excluded).

[0124]

[0131] Furthermore, the heat transfer (or heat management system) fluid may contain one or more low concentrations of soluble alkaline earth metals (e.g., selected from calcium, magnesium, or strontium), or zinc compounds, and mixtures thereof, either alone or in combination with one or more acids, for example, but not limited to benzoic acid. The soluble alkaline earth metals or zinc compounds may include hydroxides, nitrates, nitrites, other soluble metal salts, or mixtures thereof. In some cases, such compounds are metal salts selected from calcium, magnesium, strontium, or zinc carboxylates, or mixtures thereof. The term "soluble" means that the compound can dissolve in the freezing point depressant / water heat transfer fluid at a level used in the fluid, whether in fluid concentrate form or in ready-to-use / pre-diluted form, and that the compound can ionize to produce corresponding metal ions in the heat transfer fluid concentrate and / or ready-to-use (pre-diluted with deionized water) fluid. In this regard, alkaline earth metal hydroxides are intended to be used in combination with one or more acids, for example, benzoic acid, to provide a substantially neutral mixture with low conductivity.

[0125]

[0132] Optionally, other coolant additives, such as colorants, wetting agents, biocides, and nonionic dispersants, may be added to the coolant formulations disclosed in this invention. Any optional additives used in the coolant should be non-conductive or have very low electrical conductivity.

[0126]

[0133] Nonconductive colorants and colorant-treated ion exchange resins described in US7985349, US7611787, US7901824, 2006 / 0051639, and 2006 / 0063050 may be used in the present invention. In accordance with these instructions, optional additional representative non-conductive colorants or dyes include, but are not limited to, various polymer colorants from Milliken & Company in Spartanburg, SC, and colorants from Chromatech Inc. in Canton, MI, such as, but are not limited to, Liquitint Red ST, Liquitint Blue RE, Liquitint Red XC, Liquitint Patent Blue, Liquitint Bright Yellow, Liquitint Bright Orange, Liquitint Royal Blue, Liquitint Blue N-6, Liquitint Bright Blue, Liquitint Supra Blue, Liquitint Blue HP, Liquitint Blue DB, Liquitint Blue II, Liquitint Exp. Yellow 8614-6, Liquitint Yellow BL, Liquitint Yellow II, Liquitint Sunbeam Yellow, Liquitint Supra Yellow, Liquitint Green HMC, Liquitint Violet, Liquitint Red BL, Liquitint Red RL, and Liquitint Cherry. Examples include Red, Liquitint Red II, Liquitint Teal, Liquitint Yellow LP, Liquitint Violet LS, Liquitint Crimson, Liquitint Aquamarine, Liquitint Green HMC, Liquitint Blue EA, and Liquitint Red HN, and / or similar, and combinations thereof.

[0127]

[0134] As used herein, the term "non-conductive" refers to a colorant that, when introduced into a standard solution of deionized water at a maximum concentration of about 0.2% or less by weight relative to the total weight of the standard solution, results in an increase in conductivity of less than about 10 μS / cm. In some embodiments, suitable non-conductive colorants exhibit good stability in a mixture of alcohol and water under fuel cell operating conditions (e.g., typically at temperatures of about 40°C to about 100°C).

[0128]

[0135] In some embodiments, the optional nonconductive colorant is substantially free of functional groups that form ionic species by hydrolysis in an aqueous solution of alcohol or glycol. In the context of nonconductive colorants, the term “substantially free” as used herein means not exceeding an amount that would result in the electrical conductivity of the colored heat transfer fluid exceeding 10 μS / cm. In some embodiments, the optional nonconductive colorant is substantially free of functional groups selected from the group consisting of carboxhelates, sulfonates, phosphonates, quaternary ammonium cations, positively charged groups, negatively charged groups, and combinations thereof. Examples of positively charged groups include, but are not limited to, Na + Cu 2+ , N + R3(In the formula, R is independent of H, C1~C) 20 (An alkyl group or an aromatic ring-containing group), Fe 3+ Examples include, and / or similar groups, and combinations thereof. Exemplary examples of negatively charged groups include, but are not limited to, Cl - , Br - , I - Examples include, and / or similar things, and combinations thereof.

[0129]

[0136] In some embodiments, an optional nonconductive colorant may comprise at least one of the following chromophores: anthraquinone, triphenylmethane, diphenylmethane, triarylmethane, diarylmethane, azo-containing compound, diazo-containing compound, triazo-containing compound, diazo-containing compound, xanthene, acridine, indene, thiazole, two or more conjugated aromatic groups, two or more conjugated heterocyclic groups (e.g., stilbene and / or pyrazoline and / or coumarin-type groups or mixtures thereof), three or more conjugated carbon-carbon double bonds (e.g., carotene), and / or similar groups, and combinations thereof. In some embodiments, the chromophore may comprise one or more of the following: triphenylmethane, diphenylmethane, triarylmethane, diarylmethane, and azo-containing groups.

[0130]

[0137] In some embodiments, an optional nonconductive colorant may contain an alkylene oxy group or an alkoxy group and at least one chromophore as described above. In some embodiments, the chromophore contained in the colorant may be selected from the group consisting of anthraquinone, triphenylmethane, diphenylmethane, triarylmethane, diarylmethane, azo-containing compounds, diazo-containing compounds, triazo-containing compounds, diazo-containing compounds, two or more conjugated aromatic groups, two or more conjugated heterocyclic groups, and / or similar groups, and combinations thereof.

[0131]

[0138] In an alternative embodiment, a suitable optional non-conductive colorant is given by formula (IV): R{A k [(B) n R 1 ] m} x (IV) (In the formula, R is an organic chromophore selected from the group consisting of anthraquinone, triphenylmethane, diphenylmethane, triarylmethane, diarylmethane, azo-containing compounds, diazo-containing compounds, triazo-containing compounds, diazo-containing compounds, xanthene, acridine, indene, thiazole, two or more conjugated aromatic groups, two or more conjugated heterocyclic groups, and combinations thereof; A is a linking site within the chromophore and selected from the group consisting of O, N, and S; k is 0 or 1; B is selected from the group consisting of one or more alkylene oxy groups or alkoxy groups containing 1 to 8 carbon atoms; n is an integer from 1 to 100; m is 1 or 2; x is an integer from 1 to 5; R 1 (This is selected from the group consisting of H, C1-C6 alkyl groups, or alkoxy groups containing 1-8 carbon atoms, and combinations thereof.) It holds.

[0132]

[0139] In some embodiments, a suitable optional nonconductive colorant is given by formula (IV) shown above (wherein A is N or O, B is selected from the group consisting of one or more alkylene oxy components containing 2 to 4 carbon atoms, n is 1 to 30, m is 1 or 2, X is 1 or 2, R 1 These are colorants of H or C1-C4 alkyl groups or alkoxy groups containing 1-6 carbon atoms.

[0133]

[0140] In some embodiments, optional nonconductive colorants may be prepared by various known methods, for example, but not limited to, U.S. Patent No. 4,284,729, U.S. Patent No. 6,528,564, or other patents issued to Milliken & Company in Spartanburg, SC. ​​For example, a suitable optional colorant may be prepared by converting a dye intermediate containing a primary amino group into a corresponding polymer compound, and using the resulting compound to produce a compound having an intramolecular chromophore. In the case of azo dyes, this can be achieved by reacting a primary aromatic amine with a suitable amount of alkylene oxide or a mixture of alkylene oxides (e.g., ethylene oxide) according to a known procedure, and coupling the resulting compound with the diazonium salt of the aromatic amine. To prepare liquid colorants of triarylmethanes, the aromatic amine reacted with an alkylene oxide as described above may be condensed with an aromatic aldehyde, and the resulting condensation product may be oxidized to form a triarylmethane liquid colorant. Other suitable optional colorants may also be prepared by these procedures and other known procedures.

[0134]

[0141] In one embodiment, an optional colorant containing ionic species may be used when a purification method is employed. Exemplary purification and chemical separation techniques include treatment with ion exchange resins, reverse osmosis, extraction, absorption, distillation, filtration, and similar processes used to remove ionic species in order to obtain a purified colorant that is electrically nonconductive and suitable for use herein.

[0135]

[0142] In embodiments in which the heat transfer fluid includes one or more additional optional components, the total amount of the one or more additional optional components may be greater than about 0.001% by weight based on the total weight of the heat transfer fluid. Within this range, the amount of the one or more additional optional components may be less than about 20% by weight, less than about 19% by weight, less than about 18% by weight, less than about 17% by weight, less than about 16% by weight, less than about 15% by weight, less than about 14% by weight, less than 13% by weight, or less than about 12% by weight, less than about 11% by weight, less than about 10% by weight, less than about 9% by weight, less than about 8% by weight, less than about 7% by weight, less than about 6% by weight, less than about 5% by weight, less than about 4% by weight, less than 3% by weight, or less than about 2% by weight based on the total weight of the heat transfer fluid.

[0136]

[0143] The pH of the heat transfer fluid may be between approximately 4.5 and approximately 10.0 at room temperature, regardless of whether it is formulated as a concentrated solution or as a pre-diluted, ready-to-use heat transfer fluid. Within this range, the pH may be approximately 5.0 or higher, or in some embodiments, approximately 6.5 or higher. Also within this range, the pH may be approximately 9.0 or lower, or in some embodiments, approximately 7.5 or lower.

[0137]

[0144] A method for preventing corrosion in a heat transfer system according to this teaching includes bringing at least a portion of the heat transfer system into contact with a heat transfer fluid of the type described herein. The heat transfer system may include one or more components containing carbon steel, aluminum, aluminum alloys, magnesium, magnesium alloys, yellow metals, or combinations thereof. In some embodiments, the heat transfer system may include magnesium and / or magnesium alloys. In some embodiments, the heat transfer system includes a fuel cell.

[0138] Ion exchange resin

[0145] According to some embodiments for use in the described vehicles, it is intended that an ion exchange resin pre-treated with a desired corrosion inhibitor composition is used to provide the required corrosion protection. For example, the ion exchange resin (e.g., a mixed bed resin or anion exchange resin) may first be pre-treated with a corrosion inhibitor containing a five- or six-membered heterocycle as an active functional group, wherein the heterocycle contains at least one nitrogen atom, for example, an azole compound. The ion exchange resin is then filled into a filter installed in the side flow of the vehicle's cooling system. Some of the ionic species present in the coolant or generated during the operation of the cooling system will be exchanged with the corrosion inhibitor bound to the exchangeable sites on the ion exchange resin. This releases the corrosion inhibitor from the resin and removes the ionic species from the coolant.

[0139]

[0146] When the resin is initially pre-treated with a corrosion inhibitor containing a 5- or 6-membered N-heterocyclic compound, since such compounds are weak ionic compounds, their release in the coolant within the typical usage concentration range, e.g., less than several thousand milligrams per liter, will not result in an unacceptable increase in electrical conductivity. One advantage of each use of the ion exchange resins described is that the amount of corrosion inhibitor released from the resin depends on the corrosion prevention needs of the coolant. Increased corrosivity of the coolant generates more ionic species, which in turn causes an increase in the amount of corrosion inhibitor from the resin by the ion exchange mechanism. The increased concentration of corrosion inhibitor in the coolant leads to a decrease in the corrosion rate. Another advantage of using the ion exchange resins described is that the presence of a mixed-bed ion exchange resin maintains a low electrical conductivity of the coolant (heat transfer fluid or thermal management fluid composition) in the system. Where ion exchange resins are used and / or present, it is also intended to use one or more filters and / or strainers to suppress or prevent leakage of ion exchange resin beads into the system.

[0140]

[0147] Ion exchange resins supported with corrosion inhibitors can be prepared by contacting the ion exchange resin with an aqueous solution containing the corrosion inhibitor for a sufficiently long period of time, so that the corrosion inhibitor replaces 15% or more of the total exchangeable groups in the resin. In other words, the amount of corrosion inhibitor supported should reach 15% or more of the resin's exchange capacity, or more than 50% of the resin's exchange capacity, or more than 75% of the resin's exchange capacity. The ion exchange resins supported with corrosion inhibitors are then packed into filters and installed in a cooling system to provide the desired corrosion protection. Before installation in the cooling system, the ion exchange resins supported with corrosion inhibitors may be washed with deionized water and / or washed coolant to minimize the possibility of accidental contamination of the system with impurities.

[0141]

[0148] Corrosion inhibitors that can be used to treat ion exchange resins generally have a pKa value of 5 or greater when they are acids in aqueous solution at 25°C. When the treatment inhibitor is a base, the pKb value of a suitable treatment inhibitor should be 5 or greater in aqueous solution at 25°C. Suitable examples of ion exchange resin treatment inhibitors may include compounds containing a 5-membered or 6-membered heterocycle as an active functional group, the heterocycle containing at least one nitrogen atom, for example, an azole compound. In particular, benzotriazoles, tolyltriazoles, methylbenzotriazoles (e.g., 4-methylbenzotriazole and 5-methylbenzotriazole), butylbenzotriazoles, and other alkylbenzotriazoles (e.g., alkyl groups containing 2 to 20 carbon atoms), mercaptobenzothiazoles, thiazoles and other substituted thiazoles, imidazoles, benzimidazoles and other substituted imidazoles, indazoles and substituted indazoles, tetrazoles and substituted tetrazoles, and mixtures thereof can be used as corrosion inhibitors. Other compounds may also be used to treat ion exchange resins. These include amine salts of cyclohexene carboxylate compounds derived from tall oil fatty acids, as well as amine compounds such as mono, di, and triethanolamines, morpholine, benzylamine, cyclohexylamine, dicyclohexylamine, hexylamine, AMP (i.e., 2-amino-2-methyl-1-propanol or isobutanolamine), DEAE (i.e., diethylethanolamine), DEHA (i.e., diethylhydroxylamine), DMAE (i.e., 2-dimethylaminoethanol), DMAP (i.e., dimethylamino-2-propanol), and MOPA (i.e., 3-methoxypropylamine). Furthermore, other corrosion inhibitors, such as carboxylates, carboxylic acid esters, and amides, may also be used. It is also intended that one or more of the above-mentioned compounds that can be used to treat ion exchange resins may be excluded from the heat transfer fluid described.

[0142]

[0149] The ion exchange resin that can be used depends on the properties of the corrosion inhibitor used. When an N-heterocyclic compound is used as the corrosion inhibitor, the ion exchange resin may be a regenerative mixed bed resin or an anion exchange resin. When the corrosion inhibitor can become a positively charged species in solution, a regenerative mixed bed resin or a cation exchange resin can be used. The mixed bed resin may be a mixture of a cation ion exchange resin and an anion exchange resin. Typical cation exchange resins are H + It may also be in form, and the anion exchange resin is OH - It can be in any form.

[0143]

[0150] Ion exchange resins are typically formed from a polymer matrix and functional groups that interact with ions. The ion exchange matrix may be polystyrene, polyacrylic, phenol-formaldehyde, and polyalkylamines, including polystyrene and styrene copolymers. The functional groups of cationic ion exchange resins may be sulfonic acid groups (-SO3H), phosphonic acid groups (-PO3H), phosphinic acid groups (-PO2H), or carboxylic acid groups (-COOH or -C(CH3)-COOH). The functional groups of anionic ion exchange resins may be quaternary ammonium groups, such as benzyltrimethylammonium or benzyldimethylethanolammonium, or tertiary amine functional groups. Commercially available ion exchange resins are sold by companies such as Rohm and Haas (e.g., Amberlite, Amberjet, and Duolite, Imac resins), Bayer (Lewatit), Dow (Dowex), Mitsubishi (Diaion), Purolite, Sybron (Ionac), and Resintech. [Examples]

[0144]

[0151] The heat transfer fluids conforming to this teaching are further demonstrated by the following non-limiting examples. The following examples illustrate the features conforming to this teaching and are provided by illustration only. They are not intended to limit the scope of the appended claims or their equivalents.

[0145] Examples of corrosion screening tests

[0152] ASTM D1384-24 (published February 2024) is a test method using a simple beaker procedure to evaluate the effect of engine coolant on metal specimens under controlled laboratory conditions. In the following examples, a modified ASTM D1384-24 test procedure (referred to as a corrosion screening test) was used. In this procedure, coupons of metal or metal alloy were exposed to diluted heat transfer fluid compositions (diluted with fresh deionized water to yield a 50 vol% composition) as shown in Examples 1-7 and Comparative Examples 1-5, and further specified in Table 1. In Comparative Examples 6-8, commercially available pre-diluted, ready-to-use coolant solutions were used without modification (i.e., without dilution with deionized water) in the modified ASTM D1384-24 test. No corrosive salts were added to the test solution in the modified ASTM D1384-24 test. Coupons were exposed to each test solution for 336 hours, and the test solution temperature was controlled to 88°C according to the ASTM D1384-24 specification to obtain the mass loss of each coupon. The mass loss of each coupon is shown as (test piece mg) / 336 hours.

[0146]

[0153] Table 1 shows the test results obtained from the corrosion screening tests described above. The results indicate that the heat transfer fluids described provide excellent corrosion protection for various metals.

[0147]

[0154] In the examples used in Table 1, "fresh deionized water" refers to deionized water newly prepared by a reverse osmosis apparatus that does not have the opportunity to adsorb carbon dioxide from the air. The fresh deionized water used in the examples of the present invention typically had an electrical conductivity of less than 1 μS / cm.

[0148] [Table 2-1]

[0149] [Table 2-2]

[0150] [Table 2-3]

[0151] [Table 2-4]

[0152]

[0155] Furthermore, it can be confirmed that the low-electrically conductive thermal management fluid formulations of Examples #2, #4, and #7 resulted in low corrosion rates (with respect to weight loss of the metal samples) in various test metal coupons. The coupon mass loss results are well within the specification limits of ASTM D3306 for ethylene glycol or propylene glycol-based engine coolants, or ethylene glycol-based engine coolants containing glycerin, used in cooling systems for automobiles or other light load applications.

[0153]

[0156] Among the test results shown in Table 1, Examples #4 and #7 showed the best overall corrosion weight reduction results. These demonstrate that the corrosion prevention performance of the tested exemplary fluids is far superior to that of the comparable commercially available EV thermal management fluids (see Comparative Examples #6, #7, and #8).

[0154]

[0157] Figure 2A shows a photograph of the front side (i.e., the side of the coupon engraved with the identification number before the test) of five metal test specimens after being tested in the modified ASTM D1384-24 test described above (test time: 336 hours, test solution temperature: 88°C), in which a pre-diluted, ready-to-use, very low-electrical-conductivity OE BEV battery system thermal management system fluid 1 (or OE BEV coolant 1, containing approximately 52.8 vol% ethylene glycol and other additives including corrosion inhibitors) was used as the test solution without any addition of corrosive salts or dilution with additional deionized water, as further described in Comparative Example 6 above. Figure 2B shows a photograph of the back side of the five metal test specimens from Figure 2A after being tested in the modified ASTM D1384-24 test described above (see the description above for Figure 2A), as further described in Comparative Example 6 above.

[0155]

[0158] Figure 3A shows photographs of the front side of five metal test specimens after being tested in the modified ASTM D1384-24 test described above (test duration: 336 hours at 88°C), in which pre-diluted, ready-to-use low electrical conductivity OE BEV battery system thermal management fluid 2 (or OE BEV coolant 2, containing approximately 58.9 volume% ethylene glycol and other additives including corrosion inhibitors) was used as the test solution without the addition of corrosive salts or dilution with additional deionized water, as further described above as Comparative Example 7. Figure 3B shows photographs of the back side of the five metal test specimens shown in Figure 3A after being subjected to the corrosion screening test described above (see the description of Figure 3A above for test conditions), as further described above as Comparative Example 7.

[0156]

[0159] Figure 4A shows photographs of the front side of five metal test specimens after being tested in the modified ASTM D1384-24 test described above (test time: 336 hours at 88°C), in which a pre-diluted, ready-to-use, moderately electrically conductive aftermarket commercial battery system thermal management fluid (or aftermarket EV coolant, containing approximately 54.2 vol% ethylene glycol and other additives including corrosion inhibitors) was used as the test solution without any addition of corrosive salts or further dilution with deionized water, as further described above as Comparative Example 8. Figure 4B shows photographs of the back side of the five metal test specimens shown in Figure 4A after being subjected to the corrosion screening test described above (see the description of Figure 4A above for test conditions), as further described above as Comparative Example 8.

[0157]

[0160] A comparison of the photographs in the figure showing the results after the corrosion screening test reveals that, in the test conducted with the ready-to-use comparative example #7 (commercially available low-electrical-conductivity OE BEV coolant / thermal control fluid or OE BEV coolant 2), severe localized corrosion attack damage was observed in the cast aluminum, ASTM solder, and one cast iron sample.

[0158]

[0161] Furthermore, it will be observed that Example #2 exhibits far better corrosion protection against metal coupon samples than Comparative Example #6, a ready-to-use example (containing a commercially available OE BEV coolant / thermal management fluid) which also has very low electrical conductivity. (The electrical conductivity of both fluids (i.e., less than 5 μS / cm at 25°C) meets the electrical conductivity design requirements for coolants specified for use as fuel cell stack coolants in fuel cell-powered electric vehicles.)

[0162] Regarding the cast aluminum coupons, it should be noted that the relatively low weight loss results obtained in the corrosion screening tests of the prepared Example 8 fluids were somewhat misleading. As seen in Figures 4A and 4B, all the cast aluminum coupon samples were completely blackened, indicating that a high degree of aluminum corrosion occurred on the test coupons during the test. In fact, it will be understood that the corrosion weight loss results of the ASTM solder samples exceeded the limits specified in ASTM D3306. Therefore, if the black corrosion products were completely removed from the cast aluminum coupons used in the Comparative Example 8 fluid tests, the corrosion rate of the cast aluminum coupons would be much higher than those shown in Table 1.

[0159]

[0163] In comparison, the cast aluminum coupon tested with the fluid of Example #7 did not blacken (compared to Comparative Example 8), showed little sign of corrosion attack, and was consistent with the weight loss results obtained in the test and shown in Table 1.

[0160]

[0164] It should be noted that the results shown in Table 1 clearly demonstrate the unexpected synergistic effects of the corrosion inhibitor combinations disclosed in this invention. The presence of alkaline earth metal ions (in the form of calcium acetate and magnesium acetate) in the presence of tris(2-butoxyethyl) phosphate resulted in excellent corrosion inhibition for various metal samples used in corrosion screening tests (modified ASTM D1384-24 tests). This is shown, for example, in the comparative test results of Example 3 vs. Example 4 and Example 5 vs. Example 6. Furthermore, the results in Table 1 (see Examples 1, 2, 3, and Example 5 vs. Comparative Example 1) also show that even in the absence of alkaline earth metal ions, the presence of tris(2-butoxyethyl) phosphate in a specific concentration range can provide acceptable corrosion inhibition for mild steel and cast iron coupons, while simultaneously preventing the corrosion of cast aluminum coupons from increasing to unacceptable levels, as demonstrated in corrosion screening tests (i.e., modified ASTM D1384-24 tests).

[0161]

[0165] The results of Comparative Examples 2, 4, and 5 demonstrate that the addition of polyacrylate to the thermal management fluid formulation results in unexpected (and harmful) precipitate formation (or phase separation) in the heat transfer fluid (or electric vehicle thermal management fluid) disclosed in the present invention.

[0162] Examples of stagnation tests

[0166] In the following test example, automotive radiator cubes were tested according to the test conditions described in "Comparison of Extended Life Coolant Protection Performance" by Yang, B., Woyciesjes, P., and Gershun, A., SAE Technical Paper 2017-01-0627, doi:10.4271 / 2017-01-0627 and US2019 / 0225855A1. In short, sample Ford Fusion automotive radiator cubes were placed in polypropylene bottles containing 50 vol% of a coolant product or a commercially available ready-to-use coolant product and placed in test ovens controlled at 100°C, 60°C (140°F), and 37.8°C (100°F) for two weeks. After two weeks, test coolant (or heat transfer fluid) solutions were collected and subjected to analysis.

[0163]

[0167] Table 2 shows that the heat transfer fluid formulations described provide excellent corrosion protection to aluminum alloy surfaces of automotive heat exchangers manufactured using controlled atmosphere brazing processes commonly used in vehicle thermal management systems (including electric vehicles).

[0164]

[0168] Table 2 shows the results of the analysis of the heat transfer fluid solution after the test.

[0165] [Table 3-1]

[0166] [Table 3-2]

[0167]

[0169] Table 2 shows that the described low-electrical-conductivity heat transfer fluids exhibit excellent corrosion protection against the aluminum surface of an automotive radiator cube (heat exchanger) covered with potassium fluoroaluminate flux residue. In particular, the corrosion protection performance of Examples #4, #6, and #7 was superior to that provided by commercially available coolants, i.e., 50 vol% Comparative Example 9 (OE BEV coolant 3) and Comparative Example #10 (i.e., ready-to-use aftermarket EV coolant 2). Both of these comparative example coolant solutions have high electrical conductivity (i.e., higher than 2000 μS / cm at a 50 vol% concentration) and contain high concentrations of known, highly effective aliphatic carboxylate corrosion inhibitors, as well as nitrates, silicates, and azole compounds.

[0168]

[0170] The concentrations of corrosion products such as aluminum cations (Al), highly corrosive fluoride ions, and, in some cases, glycol-degrading acids (e.g., glycolate, formate) were significantly lower (or absent) in the solutions after 50 vol% radiator cube stasis tests of Examples #4, #6, and #7 under comparable test conditions compared to those detected in the commercially available EV coolant products of Comparative Examples 9 and 10 (these two comparative example coolant products are approved by OEMs and are also intended for use in engine cooling systems of internal combustion engine (ICE) vehicles).

[0169]

[0171] The test results clearly demonstrate that the described heat transfer fluids provide excellent protection to automotive heat exchangers manufactured by controlled atmosphere brazing processes under the operating conditions of electric vehicle thermal management systems. As shown in the results of Examples 3, 4, and 7, the unexpected synergistic effect of corrosion prevention of the corrosion inhibitor combinations disclosed in this invention has been demonstrated. The higher concentration of tris(2-butoxyethyl) phosphate used in Example 6 compared to the concentration used in Example 4 appears to indicate that corrosion prevention against potassium fluoroaluminate flux residue may improve with increasing neutral phosphate concentration in the heat transfer fluid formulation.

[0170]

[0172] Referring to Table 3, the test results are shown for several comparative compositions (Comparative Examples 11-15) and one composition (Example 8) according to the heat transfer fluid described above, using the modified ASTM D1384-24 test described above.

[0171] [Table 4-1]

[0172] [Table 4-2]

[0173]

[0173] As shown in Table 3, the use of triethyl phosphate as a partial or complete substitute for tris(2-butoxyethyl) phosphate in the described heat transfer fluid formulations significantly reduced the corrosion protection performance of the heat transfer fluid in the 50 vol% solution prepared for use, which was particularly pronounced with respect to corrosion protection of mild steel (or carbon steel) and cast iron under the described test conditions. Comparing the electrical conductivity results shown in Tables 1 and 3, those skilled in the art will understand that the electrical conductivity of the 50 vol% solution prepared for use tends to increase as the concentration of alkaline earth metal acetates (i.e., calcium acetate monohydrate and magnesium acetate tetrahydrate) used in the formulations increases. Therefore, the use of high concentrations of alkaline earth metal carboxylates in the formulations may be limited by the desired electrical conductivity requirements for heat transfer fluids used in thermal management systems of electric vehicles. The results in Tables 1 and 3 clearly demonstrate an unexpected synergistic effect in which the disclosed heat transfer fluid compositions provide excellent corrosion protection for various metals under the above test conditions. In particular, the presence of the disclosed amounts of tris(2-butoxyethyl) phosphate and alkaline earth metal carboxylate salts in the heat transfer fluid composition resulted in excellent corrosion resistance for various metals under the above-described test conditions, which is clearly unexpected. This is because those skilled in the art would not expect significant chemical interactions between uncharged tris(2-butoxyethyl) phosphate molecules and positively charged alkaline earth metal ions in the ethylene glycol-water test heat transfer fluid used under the modified ASTM D1384-24 test conditions.

[0174] Antifoaming performance evaluation

[0174] As described above, since air has much lower cooling and protective properties compared to liquid coolants, the ability of a heat transfer fluid to resist foaming during operation is an important consideration in heat transfer fluid compositions. Accordingly, as described above, the heat transfer fluids described include antifoaming agent raw materials or antifoaming agent compositions. In this regard, heat transfer fluids including antifoaming agent compositions and raw materials were evaluated using a modified test based on ASTM D1881-17 (published December 2017), which describes a test method for the foaming tendency of engine coolants in glassware.

[0175]

[0175] Briefly, in the modified test, a 56 vol% solution of a heat transfer fluid containing the defoaming agent raw material or composition listed in Table 4 below is blown with air (approximately 1000 ml / min) for 5 minutes while maintaining a constant temperature (approximately 88°C in one example, approximately 23°C in another example). After 5 minutes, the volume of foam generated and the time it takes for the foam to burst are measured. The acceptable foam volume is 150 ml or less, and the acceptable bursting time is 5 seconds or less.

[0176]

[0176] Referring to Table 4 below, the results of the modified ASTM D1881-17 test described are shown for seven exemplary heat transfer fluids and four comparative heat transfer fluids according to the present invention.

[0177] [Table 5-1]

[0178] [Table 5-2]

[0179] Examples of additional corrosion screening tests

[0177] As described above, ASTM D1384-24 (published February 2024) is a test method using a simplified beaker procedure to evaluate the effect of engine coolant on metal test specimens under controlled laboratory conditions. Exemplary heat transfer fluids were prepared using corrosion inhibitor raw materials and / or compositions listed in Table 5, which included tris(2-butoxyethyl) phosphate, triethanolamine, L-arginine, octylphosphonate, and specific combinations of calcium acetate and magnesium acetate. The corrosion inhibitory properties of the heat transfer fluids were evaluated using the modified ASTM D1384-24 test procedure described above, in which coupons were exposed to each test solution for 336 hours, and the test solution temperature was controlled to 88°C according to the ASTM D1384-24 specification to obtain the mass loss of each coupon. The mass loss of each coupon is expressed as (test specimen mg) / 336 hours.

[0180]

[0178] In the examples used in Table 5, "fresh deionized water" refers to deionized water newly prepared by a reverse osmosis apparatus that does not have the opportunity to adsorb carbon dioxide from the air. The fresh deionized water used in the described examples typically had an electrical conductivity of less than 1 μS / cm.

[0181]

[0179] Table 6 shows the test results obtained from the modified ASTM D1384-24 corrosion screening test described above, demonstrating that the corrosion-preventive composition contained in the heat transfer fluid described provides excellent corrosion protection for various metals.

[0182] [Table 6]

[0183] [Table 7]

[0184]

[0180] The compositions according to Example 16 (Table 5) were further evaluated using the modified ASTM D4340-19 (published June 2019) test. ASTM D4340-19 is a screening procedure for evaluating the effect of engine coolant against corrosion of aluminum cast alloys under heat transfer conditions that may be present in aluminum cylinder head engines. In this test, a heat flux is established through a typical cast aluminum alloy used in engine cylinder heads, while the specimen is exposed to engine coolant under a pressure of 193 kPa (28 psi). The temperature of the aluminum specimen is maintained at 135°C (275°F), and the test is continued for one week (168 hours). The effect of the coolant on preventing aluminum corrosion under heat transfer conditions (hereinafter referred to as heat transfer corrosion) is evaluated based on the weight change of the specimen. In the modified ASTM D4340-19 test, a 50 vol% solution of the heat transfer fluid from Example 16 was prepared by adding deionized water, and no corrosive salts were added to reproduce the conditions that can be assumed in the described heat transfer system and components.

[0185]

[0181] Furthermore, in some cases the test specimens were washed with water before measurement, and in other cases the test specimens were acid-washed before measurement. The results for each are shown in Table 7 and reported as the weight change per 168 hours.

[0186] [Table 8]

[0187]

[0182] Exemplary heat transfer fluids were prepared using corrosion inhibitor raw materials and / or compositions listed in Table 8, which included specific combinations of tris(2-butoxyethyl) phosphate, triethanolamine, 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC), octanoic acid, decanoic acid, phosphate ester H-66 or Chemfac NF100, calcium acetate, magnesium acetate, and strontium nitrate. The corrosion inhibitory properties of the heat transfer fluids were evaluated using the modified ASTM D1384-24 test procedure described above, in which coupons were exposed to each test solution for 336 hours, and the test solution temperature was controlled to 88°C according to the ASTM D1384-24 specification to obtain the mass loss of each coupon. The mass loss of each coupon is expressed as (test piece mg) / 336 hours.

[0188]

[0183] In the examples used in Table 8, fresh deionized water refers to deionized water newly prepared by a reverse osmosis apparatus that does not have the opportunity to adsorb carbon dioxide from the air. The fresh deionized water used in the described examples typically had an electrical conductivity of less than 1 μS / cm.

[0189]

[0184] Table 9 shows the test results obtained from the modified ASTM D1384-24 corrosion screening test described above, demonstrating that the corrosion-preventive composition contained in the heat transfer fluid described provides excellent corrosion protection for various metals.

[0190] [Table 9-1]

[0191] [Table 9-2]

[0192] [Table 10]

[0193]

[0185] The compositions of Examples 23 and 26 (Table 8) were further evaluated using the modified ASTM D4340-19 test described above. 50 vol% solutions of the heat transfer fluids of Examples 23 and 26 were prepared by adding deionized water, and no corrosive salts were added to reproduce the conditions that can be assumed for the heat transfer systems and components described. In addition, in some cases the test specimens were washed with water before measurement, and in other cases the test specimens were acid-washed before measurement. The results of each test are shown in Table 10 and reported as weight change per 168 hours.

[0194] [Table 11]

[0195] Examples of controlled atmosphere brazing tests

[0186] As is known, heat transfer systems may include one or more components manufactured by controlled atmosphere brazing (i.e., CAB). In some embodiments, the heat transfer system may include aluminum. In such cases, it has been found that changes in the heat transfer fluid can be more pronounced after contact with the aluminum surface of the heat exchanger manufactured by controlled atmosphere brazing (CAB) technique under the operating conditions of the engine cooling system. Potassium fluoroaluminate flux residue remaining on the aluminum surface after the CAB process may play a significant role in altering the chemical properties and protective performance of the engine coolant.

[0196]

[0187] The following examples describe three heat transfer fluids according to the present invention, wherein the corrosion inhibitor composition comprises a neutral phosphate, in particular, optionally a polyether phosphate ester or an alcohol phosphate ester (e.g., Triton® H-66 or Triton® H-55).

[0197] [Table 12]

[0198]

[0188] Using anodic polarization curve measurements under modified GM9066P test conditions, the performance of heat transfer fluids, as confirmed in Table 12, regarding the protection of cast aluminum from high-temperature corrosion under heat dissipation heat transfer conditions commonly found in engine blocks and cylinder heads was measured and compared. The test apparatus used for anodic polarization measurements was identical to that specified in GM9066P. The test solution contained the amount of coolant (diluted with deionized water) listed in Table 12. The working electrode was a potassium fluoroaluminate flux residue radiator end cut from a new North American automotive radiator (welded tube radiator). The size of the radiator tube fragment used as the working electrode was approximately 26 mm × 26 mm × 26 mm. The solution temperature was controlled to 88°C, and the electrode surface temperature was approximately 15°C higher than the solution temperature. The solution did not contain corrosive salts.

[0199]

[0189] The corrosion rate was determined by the method described in General Motors Engineering Standards document GM9066P, published in April 1989. Briefly, this method involved obtaining an anode polarization curve using a scan rate of 1 mV / sec after the solution temperature reached a steady state (i.e., 88°C) over 5-6 hours, with AgAgCl and 3M NaCl as the reference electrodes. The results are shown in Table 12 and Figures 5 and 6.

[0200] [Table 13]

[0201]

[0190] As can be seen from Table 12 and Figures 5 and 6, the corrosion prevention performance of the exemplary composition according to the present invention significantly exceeds that of the comparable OE and aftermarket BEV coolant. Furthermore, as shown in Table 12 and Figures 5 and 6, it is clear that the exemplary low-electrical-conductivity heat transfer fluid of the present invention provides far better corrosion prevention to aluminum radiator tube surfaces covered with potassium fluoroaluminate flux residue compared to Comparative Example 22 and Example 33. In particular, as can be seen from Figures 5 and 6, the low-electrical-conductivity heat transfer fluid according to the present invention provides far better corrosion prevention to aluminum radiator tube surfaces covered with flux residue than comparative example OE and aftermarket coolant products under the test conditions used, especially under stray current corrosion conditions.

[0202]

[0191] The following examples describe three heat transfer fluids according to the present invention, in which the corrosion inhibitor composition comprises an amine, particularly triethanolamine or triisopropanolamine.

[0203] [Table 14]

[0204]

[0192] Those skilled in the art will understand that Examples 33-35 identify suitable heat transfer fluid compositions according to the present invention.

[0193] Embodiments of the present invention have been described with reference to several elements, but all elements described in the embodiments described herein are illustrative and can be omitted, substituted, added, combined or rearranged where applicable to form new embodiments. Those skilled in the art will recognize by reading this specification that such additional embodiments are substantially disclosed herein. For example, where this disclosure describes characteristics, structure, size, shape, arrangement or composition of an element or process for manufacturing or using an element or combination of elements, such characteristics, structure, size, shape, arrangement or composition can also be incorporated into any other element or combination of elements, or process for manufacturing or using an element or combination of elements, described herein, to provide additional embodiments.

[0205]

[0194] Furthermore, if an embodiment is described as including some element or group of elements, additional embodiments may be essentially of or consist of that element or group of elements. Also, although the open-ended term “comprises” is used as is generally herein, additional embodiments may also be formed by replacing it with the terms “consisting essentially of” or “consisting of.”

[0206]

[0195] All patent and non-patent documents cited herein are incorporated herein by reference in their entirety, but in the event of any conflict between these disclosures or definitions, the disclosures or definitions herein shall prevail.

[0207]

[0196] When referring to elements (e.g., "one (a) freezing point depressant", "one (a) nonionic surfactant", "one (a) polyalkylene glycol", etc.), it should be understood that the use of the indefinite articles "one (a)" and "one (an)" does not preclude the presence of multiple such elements in some embodiments.

[0208]

[0197] While the concepts of this disclosure can take on various forms of modification and alternatives, detailed exemplary embodiments of the disclosure are shown as examples in the drawings. However, it should be understood that there is no intention to limit the concepts of this disclosure to the forms specifically disclosed, but rather to encompass all forms of modification, equivalents, and alternatives that fall within the spirit and scope of the invention as defined by the claims.

[0209]

[0198] The elements and features described in the attached claims can be combined in different ways to generate new claims, which are also included within the scope of the present invention. Therefore, even if the dependent claims listed below depend only on a single independent claim or dependent claim, these dependent claims can instead depend on any preceding claim, whether independent or dependent, and such new combinations are understood to constitute part of this specification.

Claims

1. A heat transfer fluid or a thermal management system fluid, [0001] Freezing point depressants; [0002] Water having an electrical conductivity of less than 5 μS / cm; and [0003] A corrosion inhibitor composition comprising one or more electrically non-conductive or low-electrical-conductivity corrosion inhibitors, or a combination of one or more organic acids and one or more organic bases; Includes, [0004] A heat transfer fluid or thermal management system fluid having an electrical conductivity of about 500 μS / cm or less.

2. The heat transfer fluid or thermal management system fluid according to claim 1, wherein the conductivity of the heat transfer fluid is about 25 μS / cm or less or about 10 μS / cm or less.

3. The heat transfer fluid or thermal management system fluid according to claim 1 or 2, wherein the freezing point depressant comprises glycerol, alcohol, ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, or a combination thereof.

4. The heat transfer fluid or thermal management system fluid according to any one of claims 1 to 3, wherein the freezing point depressant is present in an amount of about 10% to about 99.85% by weight, or about 30% to about 99.5% by weight, or about 40% to about 99% by weight, based on the total weight of the heat transfer fluid.

5. The heat transfer fluid or thermal management system fluid according to any one of claims 1 to 4, wherein the water is present in an amount of about 0.05% to about 80% by weight, based on the total weight of the heat transfer fluid.

6. The heat transfer fluid or thermal management system fluid according to any one of claims 1 to 5, wherein the corrosion inhibitor comprises one or more neutral phosphate esters.

7. The heat transfer fluid or thermal management system fluid according to claim 6, wherein the one or more neutral phosphate esters are selected from tris(2-butoxyethyl) phosphate, trialkoxyalkyl phosphate, alkylphosphonocarboxylate, alkoxylphosphonocarboxylate, and mixtures thereof.

8. The heat transfer fluid or thermal management system fluid according to claim 7, wherein the alkyl phosphonocarboxylate and alkoxyl phosphonocarboxylate are selected from triethyl phosphonoformate, triethyl phosphonoacetate, trimethyl phosphonoacetate, methyl diethyl phosphonoacetate, triethyl 2-phosphonopropionate, triethyl-3-phosphonopropionate, trimethyl-3-phosphonopropionate, and mixtures thereof.

9. The heat transfer fluid or thermal management system fluid according to any one of claims 1 to 5, wherein the combination of one or more organic acids and one or more organic bases exhibits a substantially neutral pH combination, the one or more organic acids include carboxylic acids, organic phosphates, phosphonates, and phosphinates, and the one or more organic bases include amine compounds, amino acids, azoles, and thiazoles.

10. The azole may be a substituted benzotriazole, a substituted toltriazole, or a substituted C ２ ~C ２０ A heat transfer fluid or thermal management system fluid according to claim 9, selected from the group consisting of alkylbenzotriazole, optionally substituted mercaptobenzothiazole, optionally substituted thiazole, optionally substituted imidazole, optionally substituted benzimidazole, optionally substituted indazole, optionally substituted tetrazole, tetrahydrobenzotriazole, tetrahydrotolyltriazole, and combinations thereof.

11. The C which may be substituted ２ ~C ２０ The heat transfer fluid or thermal management system fluid according to claim 10, wherein the alkylbenzotriazole comprises methylbenzotriazole, butylbenzotriazole, or a combination thereof.

12. The heat transfer fluid or thermal management system fluid according to any one of claims 1 to 11, wherein the corrosion inhibitor is present in an amount of about 0.01% by weight to about 10% by weight, based on the total weight of the heat transfer fluid.

13. A heat transfer fluid or thermal management system fluid according to any one of claims 1 to 12, further comprising one or more soluble alkaline earth metal ions.

14. The heat transfer fluid or thermal management system fluid according to claim 13, wherein the one or more soluble alkaline earth metal ions are selected from beryllium acetate, magnesium acetate, calcium acetate, strontium acetate, or a mixture thereof.

15. The heat transfer fluid or thermal management system fluid according to claim 13, wherein the one or more soluble alkaline earth metal ions include a combination of (a) an alkaline earth metal oxide or alkaline earth metal hydroxide and (b) an acid.

16. The heat transfer fluid or thermal management system fluid according to claim 12, 13, 14, or 15, wherein the one or more soluble alkaline earth metal ions are present in an amount of about 0.001% by weight to about 0.15% by weight.

17. A heat transfer fluid or thermal management system fluid according to any one of claims 1 to 16, further comprising a nonionic surfactant.

18. The nonionic surfactant is present in an amount of approximately 0.01% to approximately 0.5% by weight, based on the total weight of the heat transfer fluid. The heat transfer fluid or thermal management system fluid according to claim 17.

19. The heat transfer fluid or thermal management system fluid according to claim 17, wherein the nonionic surfactant is selected from the group consisting of sorbitan fatty acid esters, alkoxylated alcohols, polyalkylene glycol esters, copolymers of ethylene oxide and propylene oxide, polyoxyalkylene derivatives of sorbitan fatty acid esters, and combinations thereof.

20. The heat transfer fluid or thermal management system fluid according to claim 19, wherein the alkoxylated alcohol includes an ethoxylated alcohol, a propoxylated alcohol, or a combination thereof.

21. The alkoxy alcohol said above, (a) Formula: [0005]RO(CH ２ CH ２ O) ｊ (CH) ２ CH ２ CH ２ O) ｋ H [0006] (wherein R is C ４ ~C ２５ , or C ６ ~C １５ A linear primary alcohol in which j is an integer from 0 to 15, k is an integer from 0 to 15, and j + k is an integer greater than or equal to 1), or (b) Formula: [0007]RO(CH ２ CH ２ O) ｎ H [0008] (wherein R is C ４ ~C ２５ or C ６ ~C １５ (A linear primary alcohol, where n is an integer from 1 to 15), or (c) Formula: [0009]RO(CH ２ CH ２ CH ２ O) ｍ H [0010] (wherein R is C ４ ~C ２５ or C ６ ~C １５ (A linear primary alcohol, where m is an integer between 1 and 15) A heat transfer fluid or thermal management system fluid according to claim 19 or 20, comprising:

22. The heat transfer fluid or thermal management system fluid according to any one of claims 20 or 21, wherein the alkoxylated alcohol is present in an amount of about 0.001% by weight to about 1% by weight, based on the total weight of the heat transfer fluid.

23. The heat transfer fluid or thermal management system fluid according to any one of claims 1 to 22, wherein the low-conductivity corrosion inhibitor is selected from the group consisting of siloxane compounds, colloidal silica, amine salts of cyclohexene carboxylate, amine compounds, and combinations thereof.

24. C １ ~C ２０ A heat transfer fluid or thermal management system fluid according to any one of claims 1 to 23, further comprising an additive selected from the group consisting of tetraalkyl orthosilicate esters, colorants, wetting agents, biocides, surfactants, additional corrosion inhibitors, nonionic dispersants, and combinations thereof.

25. A heat transfer fluid or thermal management system fluid according to any one of claims 1 to 24, further comprising an antifoaming agent.

26. The heat transfer fluid or thermal management system fluid according to claim 25, wherein the defoaming agent comprises a composition comprising an alcohol, a fatty alcohol alkoxylate, and an optionally selected alkylethylene oxide-propylene oxide copolymer.

27. A method for preventing corrosion in a heat transfer system, comprising the step of bringing at least a portion of the heat transfer system into contact with a heat transfer fluid comprising a freezing point depressant; water having an electrical conductivity of less than 5 μS / cm; and one or more electrically non-conductive, low-electrically-conductive corrosion inhibitors, or a corrosion inhibitor composition comprising one or more organic acids and one or more organic bases, wherein the electrical conductivity of the heat transfer fluid is about 500 μS / cm or less.

28. The method according to claim 27, wherein the heat transfer system comprises components including carbon steel, aluminum, aluminum alloys, magnesium, magnesium alloys, yellow metals, or combinations thereof.

29. The method according to claim 27, wherein the heat transfer system includes a fuel cell.

30. The method according to claim 27, wherein the heat transfer system includes a thermal management system for an electric vehicle, including a battery electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, a fuel cell electric vehicle, and a range extender electric drive vehicle.

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