Heat exchange method using fluorinated compounds having low gwp

Abstract

To provide a method for exchanging heat with an object, the method comprising using a heat transfer fluid.SOLUTION: The present invention relates to a method in which the heat transfer fluid comprises one or more chemical compounds having the general formula in the figure (where: -Rf can be any C1-C10 fluorinated linear or branched carbon chain which can be partially or fully fluorinated, and can comprise O or S atoms; -X, Y and Z can be independently selected from halogens or hydrogen, with the provision that at least one of X, Y and Z is a halogen.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for exchanging heat with a body using a composition comprising selected fluorinated compounds having a low GWP as a heat transfer fluid. [Background technology]

[0002] REFERENCE TO RELATED APPLICATIONS This application claims priority to European Patent Application Publication No. 19163552.3, filed March 8, 2019, the entire contents of which are incorporated herein by reference for all purposes.

[0003] Heat transfer fluids are known in the art for use in heating and cooling systems. Typically, heat transfer fluids include water, saline solutions, alcohols, glycols, ammonia, hydrocarbons, ethers, and various halogenated derivatives of these materials, such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HFCs), (per)fluorinated polyethers (PFPEs), etc.

[0004] A heat transfer fluid is used to move heat from one object to another, typically a heat source to a heat sink, resulting in cooling of the heat source, heating of the heat sink, or removing unwanted heat generated by the heat source. The heat transfer fluid provides a thermal path between the heat source and the heat sink, and it may be circulated by a loop or other flow system to improve heat flow, or it may be in direct contact with the heat source and heat sink. Simpler systems simply use airflow as the heat transfer fluid, and more complex systems use specially designed gases or liquids that are heated or cooled in one portion of the system and then delivered in thermal contact with the target.

[0005] Computing equipment such as computers and servers generate a significant amount of heat. Large-scale developments that centralize many computers operating in a shared location, such as server farms, are becoming increasingly common. The industry of server farms, bitcoin mining farms, and other supercomputing applications is growing very rapidly. A key factor in determining the construction strategy of such facilities is the control system that allows heat to be exchanged with such computing equipment. This system, often called a "thermal management system", is typically used to cool the computing equipment during operation, but can also be used for heating, such as when starting up a system in a cold environment. Although air remains the most commonly used fluid, it has the disadvantage of requiring large air gaps between electronic boards, resulting in a very large footprint. Air cooling also requires large air conditioning engines, whose energy consumption is very large and accounts for a significant portion of the running costs of such facilities.

[0006] Recently, solutions for server thermal management based on the use of heat transfer fluids, especially liquid heat transfer fluids, have attracted great interest because they are energy efficient (using less energy than traditional air conditioning systems) and allow more servers, processors, and circuit boards to be accommodated in a smaller space.

[0007] Other important specialized applications of heat transfer fluids can be found, for example, in the semiconductor industry (TCU, thermostats, vapor phase soldering) and in the battery industry, especially the vehicle battery industry for thermal management systems.

[0008] There are a variety of heat transfer fluids used industrially in various applications, however, the selection of the appropriate fluid can be important in some applications. Some heat transfer fluids commonly used in the past are no longer practical due to their toxicity (ammonia, ethylene glycol), others have been phased out due to their environmental profile, because they are not biodegradable and / or are considered harmful to the Earth's ozone layer and / or act as greenhouse gases when dispersed in the environment.

[0009] Fluorinated liquids are very effective heat transfer fluids. There are commercial products such as Galden from Solvay and Fluorinert from 3M. They are liquid polymers that are dielectric, have high heat capacity, low viscosity, are non-toxic and chemically inert, so they can be in direct contact with electronic boards and do not chemically interact with most materials. A drawback associated with these fluorinated fluids used to date is their high GWP values.

[0010] GWP (Global Warming Potential) is a property that can be determined for a given compound that indicates how much heat a given greenhouse gas can trap in the atmosphere (consider "1" as a baseline value for CO2) and is calculated over a specific time interval, typically 100 years (GWP 100 ).

[0011] GWP 100 The determination of GWP is done by combining experimental data on the atmospheric lifetime of the compound with its radiative efficiency using special computational tools, which are standard in the art and are described for example in the comprehensive review published by Hodnebrog et al. in Review of Gephisics, 51 / 2013, p300-378. Very stable halogenated molecules such as CF4 and chloro / fluoroalkanes have very high GWPs. 100 (7350 for CF4 and 4500 for CFC-11).

[0012] Over the years, heat transfer fluids with high GWP values ​​(such as chloro / fluoroalkanes used in air conditioners) have been phased out in industry to be replaced by lower GWP 100 The lowest possible GWP has been replaced by compounds with 100 There continues to be a continuing interest in heat transfer fluids that have value.

[0013] Hydrofluoroethers, especially segregated hydrofluoroethers, have a relatively low GWP 100 On the other hand, other of their properties can be compared to the properties of CFCs used in the past, and for this reason, some hydrofluoroethers have been successfully used industrially as heat transfer fluids, for example marketed under the trade name "Novec®" by 3M.

[0014] Hydrofluoroethers are generally described as heat transfer media because of their wide temperature range over which they are liquid, and because they have low viscosity over a wide temperature range making them useful for application as low temperature secondary refrigerants for use in secondary loop cooling systems where the viscosity should not be too high at the operating temperatures.

[0015] Fluorinated ethers are described, for example, by 3M in U.S. Pat. No. 5,713,211, by Dupont in U.S. Patent Application Publication No. 2007 / 0187639, and by Solvay Solexis in WO 2007 / 099055 and WO 2010034698.

[0016] However, as shown in U.S. Pat. No. 5,713,211 (Table 5), the GWP of segregated hydrofluoroethers 100 is much lower than CFCs, but still in the range of 70-500.

[0017] TIFF2025026454000001.tif39170

[0018] Other hydrofluoroolefins are commercialized as heat transfer fluids, for example by Chemours (Opteon™) and by Honeywell (Solstice™). These compounds have a very low GWP, about 1, but unlike the compounds cited above, they are much more twistable, which therefore limits their field of use.

[0019] It therefore has good thermal and dielectric properties, is liquid over a wide range of temperatures, is non-flammable, and has a very low GWP. 100 There remains a need to develop methods for efficient heat transfer using heat transfer fluids having a viscosity of 30 or less. Summary of the Invention

[0020] The present invention relates to a method for exchanging heat with a body comprising using a heat transfer fluid, the heat transfer fluid having the general formula: TIFF2025026454000002.tif31170 (in the formula, - R f is any C1-C which may be partially or completely fluorinated 10 may be a fluorinated linear or branched carbon chain, and may contain O or S atoms, - X, Y, and Z may be independently selected from halogen or hydrogen, provided that at least one of X, Y, or Z is halogen. The present invention relates to a method comprising the step of: DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] By "electronic computing equipment" is meant any individual or array of individual computer boards, including microprocessor CPUs, GPUs, SSDs, and DDR memory, that perform computational tasks, and thus includes both large server farms, internet servers, and bitcoin mining factories, as well as small individual computers, internet servers, and computer gaming machines. Both large and small scale installations can benefit from the heat transfer methods of the present invention.

[0022] The term "semiconductor device" in the present invention includes any electronic device that exploits the properties of semiconductor materials. Semiconductor devices are fabricated both as single devices and as integrated circuits consisting of many interconnected devices (starting from 2 and going up to billions) fabricated on a single semiconductor substrate or "wafer". The term "semiconductor device" includes both basic building blocks, such as diodes and transistors, to complex structures built from these basic blocks, ranging from analog, digital and mixed-signal circuits, such as processors, memory chips, integrated circuits, circuit boards, phototubes and solar cells, sensors, etc. The term "semiconductor device" also includes any intermediate or unfinished product of the semiconductor industry derived from a wafer of semiconductor material.

[0023] The present invention relates to a method for exchanging heat with a body comprising using a heat transfer fluid, the heat transfer fluid having the general formula: TIFF2025026454000003.tif30170 (in the formula, - R f is any 1-C which may be partially or completely fluorinated 10 may be a fluorinated linear or branched carbon chain, and may contain O or S atoms, - X, Y, and Z may be independently selected from halogen or hydrogen, provided that at least one of X, Y, or Z is halogen. The present invention relates to a method comprising the step of:

[0024] Preferably, X, Y and Z may be independently selected from F, Cl, Br or hydrogen, provided that at least one of X, Y or Z is F, Cl or Br.

[0025] More preferably, at least one of X, Y or Z is Cl or Br, and even more preferably, X is selected from H and Cl, and Y and Z are selected from Cl or F. Most preferably, one of Y and Z is F, the other is Cl, and X is Cl.

[0026] In all embodiments, R f is preferably a fully fluorinated linear or branched carbon chain that may optionally contain O or S atoms, more preferably R f is a C1 carbon chain, more preferably CF3.

[0027] The most preferred compound within general formula (I) is CF3OCCl=CFCl, i.e., 1,2-dichloro-1-fluoro-2-(trifluoromethoxy)-ethene (DCFTFME).

[0028] The method of the present invention can be used to exchange heat with any object. The method of the present invention is particularly useful when the object is an electronic computing device, such as a computer server. In fact, the method of the present invention can also be used in systems that use so-called "immersion cooling" or "direct contact cooling" since it uses a heat transfer fluid that is dielectric and non-corrosive. In these systems, the fluid is placed in direct contact with the electronic circuit board. Such fluids at their operating temperature can be gas, liquid (single-phase immersion cooling) or in vapor-liquid equilibrium (i.e. near the boiling point of the liquid in so-called "two-phase immersion cooling").

[0029] In immersion cooling, electronic computing equipment such as CPUs, GPUs, memory, and other electronics including complete servers are completely submerged in a thermally conductive dielectric liquid, or coolant, and its temperature is controlled using a circulation system that pumps the liquid through piping to a heat exchanger or radiator type cooling device, which rejects heat from the coolant.

[0030] Immersion cooling of servers is becoming a popular solution for server cooling solutions, as it allows for significant reductions in energy usage by eliminating expensive air conditioning equipment. These systems are replaced by efficient low-speed liquid circulation pumps and simpler heat exchanger and / or radiator systems.

[0031] The temperature used in immersion cooling is determined by the maximum temperature at which the immersed equipment can reliably operate. For servers, this temperature range is typically 15-65 °C, although in some cases this range can be extended to 75 °C.

[0032] Current commercial applications of immersion cooling span data center oriented solutions for commodity server cooling, server clusters, HPCC applications, and Bitcoin mining, as well as mainstream cloud-based and web hosting architectures. Immersion cooling is also used in the thermal management of computing equipment associated with LEDs, lasers, x-ray machines, and magnetic resonance imaging equipment.

[0033] The method of the present invention is suitable for both single-phase and two-phase immersion cooling. Among the compounds according to the general formula (I) of the present invention, the longer R fThose with Rf chains (typically from C3 and up, see Examples 4 and 5 in the Examples section below) exist as liquids over a wide range of temperatures and are therefore suitable for open bath systems where the heat exchange composition remains liquid at all stages of operation. Typically, the heat transfer fluid is pumped to an external heat exchanger where it is cooled (or heated, if necessary) and recirculated back into the bath. More or less sophisticated control systems may exist to control the instantaneous temperature of the fluid and the temperature of the server to optimize the fluid temperature at each instant. Compounds with longer Rf chains have a lower vapor pressure, minimizing evaporation and loss of the compound.

[0034] In contrast, the shorter R f The compounds according to the general formula (I) of the present invention having a chain R f (having the formula (I)) has a relatively low boiling point in the range of 20°C to 80°C.

[0035] These low boiling compounds can be used in what is called "two-phase immersion cooling." Two-phase immersion cooling is a technology sold by Allied Control and several other companies that involves submerging electronic devices in a sealed tank in a bath of dielectric fluid. This dielectric fluid has a boiling point that corresponds to a target temperature to which the bath can be set. When the electronic devices are heated to the boiling point of the dielectric fluid, the fluid turns into a vapor with heat subtracted. The vapor then condenses on a lid or coil condenser placed over the bath and precipitates again in the bath. This type of design is particularly appreciated because it does not require recirculation of the dielectric fluid and allows many more electronic devices to be accommodated in a small space.

[0036] Furthermore, in the field of cooling computer equipment, the method of the invention can also be used in non-immersion cooling systems in which a heat exchange fluid is circulated in a closed system and is in thermal contact with the processor through a plate of thermally conductive material (such as the server cooling solution manufactured by Ebullient under the name "Module Loop"). The use of a dielectric fluid is in any case beneficial, since there is always a risk of leakage and conductive liquids can have destructive effects on electronic equipment.

[0037] The method of the present invention may also be useful in the semiconductor industry, where, for example, temperature control during the manufacture of semiconductor devices is very important. In this case, the object exchanging heat with the heat transfer fluid is the semiconductor device. Temperature control units (TCUs) are all used along the production line for the fabrication of semiconductor devices and use heat transfer fluids to remove unwanted heat during steps such as wafer etching and deposition processes, ion implantation, and lithographic processes. Heat transfer fluids are typically circulated through the wafer mount and each process tool that requires temperature control has its own individual TCU.

[0038] Some of the most important tools that contain the TCU are silicon wafer etchers, steppers, and ashers. Etching is performed using reactive plasmas at temperatures ranging from 70°C to 150°C, and the temperature of the wafer must be precisely controlled throughout the temperature range.

[0039] Steppers are used to photolithograph the wafer to form reticle lines, which are then used to expose a photosensitive mask. This process is carried out at temperatures between 40°C and 80°C, but temperature control is crucial as the wafer needs to be maintained at a precise fixed temperature (±0.2°C) along the process to ensure good results.

[0040] Ashing is a process in which the photosensitive mask is removed from the wafer, performed at temperatures between 40° C. and 150° C. The system uses plasma, and again, precise temperature control is particularly important.

[0041] Another related process is plasma enhanced chemical vapor deposition (PECVD) where a film of silicon oxide, silicon carbide and / or silicon nitride is grown on the wafer in a chamber. Again, the temperature at which this step is carried out can be selected in the range of 50° C. to 150° C., but the wafer must be kept uniformly at the selected temperature throughout the deposition process.

[0042] In a semiconductor device manufacturing facility, typically each etcher, asher, stepper and plasma enhanced chemical vapor deposition (PECVD) chamber has its own TCU through which heat transfer fluid is recirculated.

[0043] Another process step in which heat transfer fluids are used in the manufacture of semiconductor devices is vapor phase reflow (VPR) soldering. This is the most common method used to bond surface mount devices, multi-chip modules, and hybrid components to circuit boards. In this method, the soldering material is applied in paste form, and then the semiconductor device, e.g., an unfinished circuit board, is placed in a sealed chamber containing the heat transfer fluid at its boiling point in equilibrium with its vapor phase. The vapor phase fluid transfers heat to the soldering paste, which then melts and stabilizes the contacts. In this case, the fluid must be dielectric and noncorrosive, since it is in direct contact with the circuit board. For this application, it is important that the heat transfer fluid comprises a composition that has a sufficient boiling point to melt the soldering paste.

[0044] Another system that is an important part of the manufacturing process of many semiconductor devices is the thermal shock test. In the thermal shock test, the semiconductor device is tested at two very different temperatures. Different standards exist, but in general the test consists in bringing the semiconductor device to a high and low temperature and then testing the physical and electronic properties of the device. Typically, the semiconductor device to be tested is directly immersed alternately in a high temperature bath (which can be at a temperature between 60°C and 250°C) and a low temperature bath (which can be at a temperature between -10°C and -100°C, typically). The transfer time between the two baths must be minimized, generally less than 10 seconds. Also in this test, the fluid that constitutes the bath is in direct contact with the device and therefore must be dielectric and non-corrosive. In addition, to avoid contamination of the baths, it is highly preferred that the same fluid is used both in the low temperature bath and in the high temperature bath. Therefore, a heat transfer fluid that exists as a liquid over a wide range of temperatures is preferred.

[0045] Heat transfer fluids for use in the manufacture of semiconductor devices are typically liquids that exist in the liquid state over a wide temperature range, are dielectric, non-corrosive, and have relatively low viscosities that make them easily pumpable.

[0046] The method of the present invention can be used in all steps of semiconductor device manufacturing where the semiconductor device requires heat exchange with a heat transfer fluid, particularly with semiconductor processing equipment such as etchers, ashers, steppers and plasma enhanced chemical vapor deposition (PECVD) chambers, each of which requires precise temperature control and / or heat dissipation and therefore is equipped with a temperature control unit (TCU) that can contain the selected heat transfer fluid of the method of the present invention.

[0047] In addition, for thermal shock testing, which is an integral part of semiconductor device manufacturing, semiconductor devices are cooled and heated using at least two baths made of heat transfer fluids, a low-temperature bath, typically at a temperature between -10 and -100°C, and a high-temperature bath, typically at a temperature between 60°C and 250°C. Advantageously, the method of the invention can be used to select a suitable compound or blend of compounds according to general formula (I) constituting the heat transfer fluid for the baths. Preferably, the heat transfer fluid should be selected so that the same heat transfer fluid can be used in both baths thanks to the wide temperature range in which the fluid is in the liquid state, so that there is no risk of cross-contamination of the baths. In this case, R f Compounds of general formula (I) having a C3 to C10 chain as the alkyl group are preferred.

[0048] The method of the present invention may also find application in vapor phase soldering, and indeed the selected heat transfer fluid of the method of the present invention may be formulated to have a boiling point along the boiling point of the soldering paste, so that a semiconductor device containing a soldering paste that must be further "cured" may be introduced into a sealed chamber containing the selected heat transfer fluid of the method of the present invention at its boiling point in equilibrium with its heated vapor phase. The heated vapor will transfer heat to the semiconductor device, thereby melting the soldering paste and thus fixing the contacts as required. For this application, a high boiling point compound according to general formula (I) must be used in the heat transfer fluid, R f Compounds of general formula (I) having a C4-C10 chain as the alkyl group are preferred due to their high boiling points.

[0049] An additional advantage is that a single heat transfer fluid can be used for multiple applications, potentially enabling the use of a single heat transfer fluid throughout an entire semiconductor device manufacturing facility.

[0050] Another area in which the method of the invention may be useful is the thermal management of batteries, particularly rechargeable batteries such as vehicle batteries in cars, trams, trains, etc.

[0051] Recently, most of the developments in the field of rechargeable batteries across the industry have focused on lithium-ion based batteries based on different types of lithium salts. Batteries based on lithium manganese oxide, lithium iron phosphate and lithium nickel manganese cobalt oxide are applied, for example, in vehicles, power tools, electric bicycles, etc. Batteries based on lithium cobalt oxide are typically used in smaller size and less intensive applications, such as mobile phones, portable computers and cameras. Batteries based on lithium nickel cobalt aluminum oxide and lithium titanate are considered in applications requiring high power and / or capacity, such as electric powertrains and grid storage. Of course, new technologies outside the realm of lithium-ion based batteries are also being explored and constantly developed. The method of the present invention is not tied to a particular battery technology and is applicable to both current and next generation battery systems.

[0052] Unlike conventional power systems, batteries, and especially rechargeable batteries, have stringent requirements for their operating environment: Batteries tend to operate best within a relatively narrow temperature range.

[0053] Generally, low temperatures affect the chemical properties of the battery, slowing down the reaction rate and thus reducing the flow of electricity during charging or discharging. High temperatures increase the reaction rate and at the same time increase the energy dissipation, thus generating even more excess heat, which may cause an uncontrolled increase in temperature and irreversible damage to the cell. In a typical Li-ion battery, a temperature exceeding 80°C in only a part of its structure may initiate an exothermic chemical reaction that causes a further increase in temperature of the battery, eventually resulting in the complete destruction of the battery and the risk of fire and explosion.

[0054] On the other hand, practical applications of batteries require them to be efficient over a much wider temperature range. For example, vehicle batteries need to function properly in any environment in which people are expected to use them, so they need to operate over a temperature range of -20°C to +40°C or higher. In addition, the charging and discharging cycles of the battery can generate heat in the battery itself, making it much more difficult to maintain the battery within an acceptable temperature range.

[0055] The labelling of a typical Li-ion battery indicates that the usable range is usually -20°C to 60°C, but good power output is only obtained from 0°C to 40°C, where optimal performance is only obtained from 20°C to 40°C. Temperature also affects the duration of a battery, and in fact the number of charge / discharge cycles a battery can withstand before it is considered depleted drops rapidly below 10°C due to anode plating, and above 60°C due to degradation of the electrode material. The temperature range for optimal performance may differ for different battery chemistries and constructions, however, all current commercial batteries share a relatively narrow temperature range where their performance is optimal. It is also generally important to ensure that the entire battery is held uniformly at the same temperature, with no hot or cold areas, which can reduce its life and safety.

[0056] For this reason, it is now common practice to incorporate battery thermal management systems (BTMS) into commercial battery assemblies, especially when battery safety, reliability and life span are of major concern. These BTMS can be more or less complex depending on the type of battery, however one common element is the presence of a heat transfer fluid, such as a gas or liquid, that exchanges heat with the battery, thus heating or cooling it.

[0057] Therefore, battery thermal management systems (BTMS) are very important especially in applications that require high power and high reliability, such as vehicle batteries. Although BTMSs can be more or less complex depending on the application, each BTMS has at least the function of cooling the battery when its temperature is very high and heating the battery when its temperature is very low, typically using a heat transfer fluid that exchanges heat with the battery. Other common features of BTMSs are an insulation system to reduce the effect of the external environment on the battery temperature and a ventilation system to help dissipate dangerous gases that may occur within the battery pack. However, the method of the present invention, specifically related to the heat exchange function of the BTMS, can be easily applied to any BTMS and can incorporate other functions and features.

[0058] BTMSs that use liquids as heat transfer fluids are common because liquids can transfer larger amounts of heat more quickly than gases. Typically, the fluid is circulated by a pump in a closed system that is in thermal contact with the battery and a second system that functions to heat and / or cool the fluid to the desired temperature. This second system can include any combination of cooling and heating systems, or can combine heating and cooling functions in a heat pump. The circulating fluid absorbs heat from or releases heat to the battery, which is then circulated in said second system, returning the fluid to the desired temperature. There can be more or less sophisticated control systems that control the temperature of the fluid and the temperature of the battery that optimize the temperature of the fluid at each moment.

[0059] In some systems, the fluid circulated in the system can therefore be in direct contact with the battery cells immersed therein. Obviously, in these cases, the fluid must be dielectric to protect the battery cells and their electronic components. In other cases, the heat transfer fluid is circulated in a separate sealed system that simply exchanges heat by indirect contact, for example through heat exchange plates made of metal or other thermally conductive materials. Since sealed systems have a high risk of leakage in any case, a dielectric fluid can also be advantageous in this type of system.

[0060] Especially for high power batteries, where thermal management systems based on fluids, especially liquids, are used, the method of the present invention provides a reduced GWP 100 This provides improved thermal management in

[0061] Beyond the listed applications, the method of the present invention can also be adapted to any heat exchange method, such as heating or cooling compartments (e.g. food compartments), including on board aircraft, vehicles or ships, heating or cooling industrial production equipment, heating or cooling batteries during operation, forming thermostatic baths.

[0062] As mentioned in the introduction, heat transfer fluids used in these fields include fluorochemicals, especially hydrofluoroethers, which find application in these fields due to their chemical inertness, dielectric properties, the wide T range in which they are liquid and pumpable (typically having a viscosity of 1-50 cps at the temperature of use), low flammability and relatively low GWP.

[0063] Commercially available hydrofluoroethers for use in these areas, for example, combine all these properties with a relatively low GWP of about 70 to 300. 100 The Novec™ series from 3M combines

[0064] Furthermore, GWP has also become an important property in recent years due to the regulatory environment, and therefore there is a constant demand to develop new heat exchange fluids that have even lower GWP than the currently commercialized hydrofluoroethers.

[0065] Applicant has unexpectedly found that the heat transfer fluids used in the method of the present invention are non-flammable, provide efficient heat transfer, can be used over a wide temperature range, and have equivalent or improved dielectric properties to other hydrofluoroethers commercialized as heat transfer fluids. Surprisingly, the heat transfer fluids used in the present invention have extremely low GWPs, generally below 30 and even below 3 for some materials, as shown below in the experimental section. 100 This is a particularly unexpected result, and indeed previous reviews such as Hodnebrog et.al. cited above did not study or suggest fluorinated vinyl ether compounds as low GWP compounds.

[0066] Therefore, these selected compounds according to general formula (I) can be used to formulate heat transfer fluids having GWP100 values ​​of less than 30, preferably less than 10, and more preferably less than 5. The heat transfer fluids according to the invention also have low toxicity and exhibit good heat transfer properties and relatively low viscosity over the entire range. The fluids of the invention also have excellent electrical compatibility, i.e., they are non-corrosive, have high dielectric strength, high volume resistivity and low solvency for polar materials. The electrical properties of the fluids of the invention are such that they can be used in immersion cooling systems for electronics in direct contact with the circuitry as well as in indirect contact applications using loops and / or conductive plates.

[0067] Heat transfer fluids for use in the process of the present invention preferably comprise more than 5% by weight, more preferably more than 50% by weight, even more preferably more than 90% by weight of one or more compounds according to formula (I) above. In one embodiment, the heat transfer fluid is entirely composed of one or more compounds according to the general formula above.

[0068] In some embodiments, the heat transfer fluids of the present invention comprise a blend of compounds according to formula (I).

[0069] The method of the present invention can be applied to any heating and / or cooling system that uses a heat transfer fluid, particularly all of those exemplified herein, particularly for temperature control of electronic computing equipment, both in immersion cooling of such equipment where electronic circuit boards are directly immersed in liquid, and in distribution systems where a fluid is distributed to a cooling element that can exchange heat with a substrate, such as a plate of a thermally conductive material, such as a metal or metal alloy.

[0070] Another application is the thermal management of batteries, especially rechargeable batteries for vehicles, such as cars, trams, trains, etc.

[0071] Further applications are found in the semiconductor industry where the subject of heat exchange is a semiconductor device, such as temperature control units (TCUs) for etchers, ashers, steppers, and PECVD chambers, thermostats for thermal shock testing, and vapor phase soldering.

[0072] In another aspect, the invention also encompasses an apparatus comprising an electronic computing device and a heat transfer fluid comprising one or more compounds having the general formula (I).

[0073] In a further aspect, the present invention relates to an apparatus comprising a battery, preferably a rechargeable battery, and a thermal management system of said battery, said thermal management system of said battery comprising a heat transfer fluid in heat exchange with said battery, said heat transfer fluid comprising one or more compounds having general formula (I).

[0074] To the extent that the disclosures of any patents, patent applications, and publications incorporated herein by reference conflict with the statements of this application to the extent that a term may be unclear, this statement shall control.

[0075] The invention will now be described in more detail with reference to the following examples, the purpose of which is merely illustrative and not intended to limit the scope of the invention.

[0076] standard: Electrical properties are measured according to the following standards: Volume Resistivity - ASTM D5682-08

[2012] Dielectric Strength – ASTM D877 / D877M-13 Dielectric constant – ASTM D924-15 I followed the instructions. EXAMPLES

[0077] Example 1 – Synthesis of CF3OCCl=CFCl Step 1 – Addition of CF3OF to trichloroethylene (TCE). 100 g of ether CFCClCFCl as a solvent and 5.0 g of TCE were placed in a 100 cc stainless steel reactor equipped with a mechanical stirrer. The reactor was then cooled to -50°C in a low temperature bath. 43.5 g of TCE as a gas was pumped into the reactor for 10 hours from an inlet, and at the same time, a total of 0.89 moles of trifluoromethyl hypofluorite (obtained from COF2 and F2 according to the teachings of U.S. Pat. No. 4,900,872) diluted with helium in a molar ratio of He / CF3OF=2.0 was fed from another inlet. The molar ratio CF3OF / TCE was 1.5, and CF3OF was added at 0.089 moles / h. At the end of the reaction, 185.7 g of the mixture was taken out. The mixture contained CF3OCHClCCl2F and CF3OCCl2CHClF in a molar ratio of 95 / 5 with a yield of both compounds of 96 mol %.

[0078] Step 2 - Dehydrochlorination of CF3OCHClCCl2F and CF3OCCl2CHClF 60 g of the mixture obtained in step 1 and 5.0 g of tetrabutylammonium hydroxide in 40 wt% aqueous solution were placed in a 250 cc 4-neck glass reactor equipped with a magnetic stirrer, a dropping funnel, a thermometer and a water condenser. Then 20.5 g of NaOH in 20 wt% aqueous solution were added with vigorous stirring: the temperature was maintained at about 35°C with a H2O / ice bath. After the addition of NaOH was complete, the mixture was stirred for another 30 minutes. At the end of the reaction, the mixture was cooled to 20°C and poured into a separatory funnel: two phases were present, the lower phase (47.7 g), which was organic, was separated and distilled through a fractionation column. CF3OCCl=CFCl (boiling point 55°C) was obtained with a purity of 99.9 mol%. The yield of step 2 was 93 mol%.

[0079] Example 2 – Synthesis of CF3CF2OCCl=CFCl Step 1 – Addition of CF3CF2OF to trichloroethylene (TCE) Following the same procedure and equipment as in "Example 1 - Step 1", 100 g of CF3OCFClCF2Cl ether as solvent and 5.0 g of TCE were added to the reactor. Then, at -70°C, 43.5 g of TCE were pumped into the reactor in 10 hours, and at the same time, 0.89 moles of pentafluoroethyl hypofluorite CF3CF2OF (hypofluorite ester is obtained from CF3COF and F2 according to the teachings of US Patent No. 4,900,872) diluted with helium in a molar ratio of He / CF3CF2OF=10 was fed in 10 hours. The resulting molar ratio CF3CF2OF / TCE was 1.4, and CF3CF2OF was added at 0.089 moles / h.

[0080] The resulting mixture (205.0 g) contained two reaction products, CF3CF2OCHClCCl2F and CF3CF2OCCl2CHClF. The yield of the two addition products was 62 mol %.

[0081] Step 2 - Dehydrochlorination of CF3CF2OCHClCCl2F and CF3CF2OCCl2CHClF 60 g of the mixture from step 1 and 5.0 g of tetrabutylammonium hydroxide in 40 wt% aqueous solution were placed in a 250 cc 4-neck glass reactor equipped with a magnetic stirrer, dropping funnel, thermometer, and water condenser. Then 17 g of NaOH in 20 wt% aqueous solution was added with vigorous stirring: the temperature was maintained at about 35°C with a H2O / ice bath. After the addition of NaOH was complete, the mixture was stirred for an additional 30 min.

[0082] At the end of the reaction, the mixture was cooled to 20° C. and poured into a separatory funnel: two phases were present, the lower organic phase (48.8 g) was separated and distilled through a fractionation column. CF3CF2OCCl=CFCl (boiling point 73° C.) of 99.8 mol % purity was obtained with a yield of 93 mol % for step 2.

[0083] Example 3 – Synthesis of CF3CF2CF2OCCl = CFCl Step 1 - Addition of CF3CF2CF2OF to trichloroethylene (TCE) Following the same procedure and equipment as in "Example 1 - Step 1", 100 g of CF3OCFClCF2Cl ether as solvent and 5.0 g of TCE were added to the reactor. Then, at -80°C, 43.5 g of TCE was pumped into the reactor in 10 hours, and at the same time, 0.89 moles of heptafluoropropyl hypofluorite CF3CF2CF2OF (hypofluorite ester is obtained from CF3CF2COF and F2 according to the teachings of US Patent No. 4,900,872) diluted with helium in a molar ratio of He / CF3CF2CF2OF=10 was fed in 10 hours. The resulting molar ratio CF3CF2CF2OF / TCE was 1.4, and CF3CF2CF2OF was added at 0.089 moles / h.

[0084] The resulting mixture (230.0 g) contained two reaction products: CF3CF2CF2OCHClCCl2F and CF3CF2CF2OCCl2CHClF. The yield of the two addition products was 40%.

[0085] Step 2 - Dehydrochlorination of CF3CF2CF2OCHClCCl2F and CF3CF2CF2OCCl2CHClF 50 g of the mixture from step 1 and 4.0 g of tetrabutylammonium hydroxide in 40 wt% aqueous solution were placed in a 250 cc 4-neck glass reactor equipped with a magnetic stirrer, dropping funnel, thermometer, and water condenser. Then 15 g of NaOH in 20 wt% aqueous solution was added with vigorous stirring: the temperature was maintained at about 35°C with a H2O / ice bath. After the addition of NaOH was complete, the mixture was stirred for an additional 30 min.

[0086] At the end of the reaction, the mixture was cooled to 20° C. and poured into a separatory funnel: two phases were present, the lower organic phase (48.8 g) was separated and distilled through a fractionation column. CF3CF2CF2OCCl=CFCl (boiling point 93° C.) of 99.8 mol % purity was obtained. The yield for step 2 was 92 mol %.

[0087] Example 4 – Synthesis of (CF3)2CFCF2OCCl=CFCl Step 1 - Addition of (CF3)2CFCF2OF to trichloroethylene (TCE) Following the same procedure and equipment as in "Example 1 - Step 1", 100 g of CF3OCFClCF2Cl ether as solvent and 5.0 g of TCE were added to the reactor. Then, at -80°C, 23 g of TCE were pumped into the reactor in 10 hours, and at the same time, 0.45 moles of nonafluoroisobutyroyl hypofluorite (CF3)2CFCFOF (hypofluorite ester is obtained from (CF3)2CFCF2COF and F2 according to the teachings of US Pat. No. 4,900,872) diluted with helium in a molar ratio of He / (CF3)2CFCF2OF=15 was fed in 10 hours. The resulting molar ratio (CF3)2CFCF2OF / TCE was 1.5, and (CF3)2CFCF2OF was added at 0.045 moles / h.

[0088] The resulting mixture (181.0 g) contained two reaction products: (CF3)2CFCF2OCHClCCl2F and (CF3)2CFCF2OCCl2CHClF. The yield of the two addition products was 20%.

[0089] Step 2 - Dehydrochlorination of (CF3)2CFCF2OCHClCCl2F and (CF3)2CFCF2OCCl2CHClF 20 g of the mixture from step 1 and 2.0 g of tetrabutylammonium hydroxide in 40 wt% aqueous solution were placed in a 250 cc 4-neck glass reactor equipped with a magnetic stirrer, dropping funnel, thermometer, and water condenser. Then 15 g of NaOH in 20 wt% aqueous solution was added with vigorous stirring: the temperature was maintained at about 35°C with a H2O / ice bath. After the addition of NaOH was complete, the mixture was stirred for an additional 30 min.

[0090] At the end of the reaction, the mixture was cooled to 20°C and poured into a separatory funnel: two phases were present, the lower organic phase (17.1 g) was separated and distilled through a fractionation column. (CF3)2CFCF2OCCl=CFCl (boiling point 113°C) of 99.8 mol% purity was obtained. The yield for step 2 was 96 mol%.

[0091] Example 5 – Synthesis of CF3CF2OCF2CF2OCF2CF2OCCl = CFCl Step 1: Fluorination of CF3CF2OCF2CF2OCF2COF in the presence of CHCl=CCl2 40 g of CF3OCFClCF2Cl as solvent, 20 g of CF3CF2OCF2CF2OCF2C(O)F (prepared as described in U.S. Pat. No. 9,416,085), and 50 g of TCE were placed in the same reactor as in Example 1. The reaction mixture was kept at −75° C. and 0.067 mol / h of fluorine diluted with helium (1 / 5 F2 / He in molar terms) was fed into it for 5 hours.

[0092] The resulting mixture was distilled through a 60-plate Spalthror Fischer distillation apparatus to give 20.5 g of CF3CF2OCF2CF2OCF2CF2OCHClCCl2F and CF3CF2OCF2CF2OCF2CF2OCCl2CHClF for a combined yield of 69 mol %.

[0093] Step 2 Dehydrochlorination of CF3CF2OCF2CF2OCF2CF2OCHClCCl2F and CF3CF2OCF2CF2OCF2CF2OCCl2CHClF 20 g of the mixture from step 1 and 2.0 g of tetrabutylammonium hydroxide in 40 wt% aqueous solution were placed in a 250 cc 4-neck glass reactor equipped with a magnetic stirrer, dropping funnel, thermometer, and water condenser. 5 g of NaOH in 20 wt% aqueous solution was then added with vigorous stirring: the temperature was maintained at about 35°C with a H2O / ice bath. After the addition of NaOH was complete, the mixture was stirred for an additional 30 min.

[0094] At the end of the reaction, the mixture was cooled to 20° C. and poured into a separatory funnel: two phases were present, the lower phase (18.5 g), which was organic, was separated and distilled through a fractionation column. The distilled product consisting of CF3CF2OCF2CF2OCF2CF2OCCl=CFCl (boiling point 150° C.) was obtained with a purity of 99.8 mol %. The yield for step 2 was 96 mol %.

[0095] Example 6 – Synthesis of CF3OCH=CHF Step 1: Addition of CF3OF to 1,2-dichloroethylene (DCE) Following the same procedure and equipment as in "Example 1 - Step 1", 100 g of CF3OCFClCF2Cl ether as solvent and 5.0 g of DCE were added to the reactor. Then, at -80°C, 40 g of DCE was pumped into the reactor in 7.5 hours, and at the same time, 0.67 moles of trifluoromethyl hypofluorite CF3OF (hypofluorite ester is obtained from COF2 and F2 according to the teachings of US Patent No. 4,900,872) diluted with helium in a molar ratio of He / CF3OF=5 was fed in 7.5 hours. The resulting molar ratio CF3OF / DCE was 1.5, and CF3CF2OF was added at 0.089 moles / h.

[0096] The resulting mixture (192.0 g) contained CF3OCHClCHClF. The yield was 96%.

[0097] Step 2: Dechlorination of CF3OCHClCHClF 100 ml of dimethylformamide (DMF), 20 g of Zn powder, and 2 g of ZnCl2 were placed in a 250 cc three-neck glass reactor equipped with a magnetic stirrer, a dropping funnel, a thermometer, and connected to a cold trap at -75°C via a Vigreux column and a water condenser. The temperature of the reactor was brought to 65°C, and 50 g of CF3OCHClCHClF was added dropwise under mechanical stirring. After the addition, the mixture was stirred for an additional hour.

[0098] 27.8 g of the mixture was collected in the cold trap. 1H and 19F NMR confirmed the presence of 99.6% pure product CF3OCH=CHF (boiling point 15°C). The yield of step 2 was 86 mol%.

[0099] Example 7 – Synthesis of CF3OCH=CClF and CF3OCCl=CHCF Step 1: Same as step 1 in Example 1

[0100] Step 2: Dehydrochlorination of CF3OCHClCCl2F and CF3OCCl2CHClF 100 ml of dimethylformamide (DMF), 25 g of Zn powder, and 2 g of ZnCl2 were placed in a 250 cc three-neck glass reactor equipped with a magnetic stirrer, a dropping funnel, a thermometer, and connected to a cold trap at -75°C via a Vigreux column and a water condenser. The temperature of the reactor was brought to 75°C, and 60 g of the mixture obtained in step 1 (containing CF3OCHClCCl2F and CF3OCCl2CHClF in a molar ratio of 95 / 5) was added dropwise under mechanical stirring. After the addition, the mixture was stirred for another hour.

[0101] 34.0 g of the mixture was collected in the cold trap. 1H and 19F NMR confirm the presence of two products CF3OCH=CClF and CF3OCCl=CHCF in a molar ratio of 95 / 5. The yield of step 2 was 81 mol %. The two compounds were then separated by distillation using a 10-plate column. CF3OCH=CClF (boiling point 20°C) was obtained with a purity of 99.7 mol %.

[0102] GWP measurement GWP of 1,2-dichloro-1-fluoro-2-(trifluoromethoxy)-ethene (DCFTFME) 100 was performed at 3500-400 cm following the procedure established at the University of Oslo. -1 The GWP was determined by measuring the integrated absorption cross section in the infrared region of the spectrum, calculating the rate of reaction with OH radicals, and calculating the resulting atmospheric lifetimes and radiative forcing efficiencies. As a result of these measurements, a GWP of 2.6 was determined. 100 was obtained. GWP for DCFTFME 100 Measurement related data: 3500~400cm -1 The integrated absorption cross section at 36.6*10^-17cm 2 molecule -1 cm -1 Radiative forcing efficiency (calculated value) = 0.435 Wm -2 OH radical reaction rate at 298K k DCFTFME+OH =5×10 -13 cm3 molecule -1 s -1 Atmospheric lifetime of DCFTFME < 1 month GWP 100 =2.6

[0103] Electrical and thermal properties compared to other commercially available hydrofluoroethers:

[0104] TIFF2025026454000004.tif46170

[0105] Further physical properties of the compounds according to the invention:

[0106] TIFF2025026454000005.tif94170

[0107] The results show how the compounds of the present invention have overall similar or improved properties and lower GWP when compared to existing commercially available materials used for similar purposes. Heat transfer fluids containing these compounds can be used in all of the applications mentioned, including heat exchange with electronic computing equipment, batteries, or semiconductor devices.

Claims

1. 1. A method for exchanging heat with a body comprising using a heat transfer fluid, the heat transfer fluid having the general formula: (In the formula, - R ｆ is any C, which may be partially or fully fluorinated １ ~C １０ may be a fluorinated linear or branched carbon chain of the formula: - X, Y, and Z may be independently selected from halogen or hydrogen, provided that at least one of X, Y, or Z is halogen. The method includes one or more compounds having the formula:

2. 2. The method of claim 1, wherein the one or more compounds of general formula (I) constitute at least 5% by weight of the heat transfer fluid, preferably more than 50% by weight, more preferably more than 90% by weight.

3. The heat transfer fluid has a GWP, determined according to the method reported in Hodnebrog et al., Review of Gephisics, 51 / 2013, p300-378, of less than 30, preferably less than 10, more preferably less than 5. １００ The method according to claim 1 or 2, comprising:

4. The method of any one of claims 1 to 3, wherein the object is an electronic computing device.

5. The method of claim 4 , wherein the electronic computing device is one or more servers.

6. 6. The method of claim 4 or 5, wherein the electronic computing device includes one or more electronic circuit boards, the method comprising the step of directly contacting the electronic circuit boards with the heat transfer fluid.

7. The method according to any one of claims 4 to 6, which is a single-phase immersion cooling method.

8. The method according to any one of claims 4 to 6, which is a two-phase immersion cooling method.

9. The method according to any one of claims 1 to 3, wherein the object is a battery, preferably a rechargeable battery, more preferably a rechargeable vehicle battery.

10. The method of any one of claims 1 to 3, wherein the object is a semiconductor device.

11. 1. A method for manufacturing a semiconductor device, comprising using one or more semiconductor processing equipment selected from an etcher, an asher, a stepper, and a plasma enhanced chemical vapor deposition (PECVD) chamber, the semiconductor processing equipment including at least one temperature control unit (TCU) in heat exchange with the semiconductor device, the TCU including the heat transfer fluid; The heat transfer fluid has the following general formula: (In the formula, - R ｆ is any C, which may be partially or fully fluorinated １ ~C １０ may be a fluorinated linear or branched carbon chain of the formula: - X, Y, and Z may be independently selected from halogen or hydrogen, provided that at least one of X, Y, or Z is halogen. The method of claim 1, further comprising:

12. 1. A method for thermal shock testing of a semiconductor device, the method comprising, in any order: i. cooling said semiconductor device to a temperature comprised between −10° C. and −100° C. using a first bath made of a heat transfer fluid; ii. Heating the semiconductor to a temperature comprised between 60° C. and 250° C. using a second bath made of a heat transfer fluid; Including, One or preferably both of the first and second baths are of the general formula: (In the formula, - R ｆ is any C, which may be partially or fully fluorinated １ ~C １０ , preferably C ３ ~C １０ may be a fluorinated linear or branched carbon chain of the formula: - X, Y, and Z can be independently selected from halogen or hydrogen, provided that at least one of X, Y, or Z is halogen. The method of claim 1, wherein the heat transfer fluid is made of a heat transfer fluid comprising one or more compounds having the formula:

13. A method for vapor phase soldering of a semiconductor device, comprising the steps of: i. providing a semiconductor device comprising a soldering paste; ii. providing an enclosed chamber containing a heat transfer fluid at its boiling point such that heated vapor of said heat transfer fluid is produced within said enclosed chamber; iii. introducing the semiconductor device into the sealed chamber in contact with the vapor of the heat transfer fluid, thereby melting the soldering paste upon contact with the heated vapor; Including, The heat transfer fluid has the following general formula: (In the formula, - R ｆ is any C, which may be partially or fully fluorinated １ ~C １０ , preferably C ４ ~C １０ may be a fluorinated linear or branched carbon chain of the formula: - X, Y, and Z can be independently selected from halogen or hydrogen, provided that at least one of X, Y, or Z is halogen. The method of claim 1, further comprising:

14. 1. An apparatus comprising an electronic computing device and a heat transfer fluid, the heat transfer fluid having the general formula: (In the formula, - R ｆ is any C, which may be partially or fully fluorinated １ ~C １０ may be a fluorinated linear or branched carbon chain of the formula: - X, Y, and Z can be independently selected from halogen or hydrogen, provided that at least one of X, Y, or Z is halogen. The method of claim 1, further comprising:

15. 1. An apparatus comprising a battery, preferably a rechargeable battery, and a thermal management system for said battery, said thermal management system comprising a heat transfer fluid for exchanging heat with said battery, said heat transfer fluid having the general formula: (In the formula, - R ｆ is any C, which may be partially or fully fluorinated １ ~C １０ may be a fluorinated linear or branched carbon chain of the formula: - X, Y, and Z can be independently selected from halogen or hydrogen, provided that at least one of X, Y, or Z is halogen. The method of claim 1, further comprising:

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