Additive for thermal management fluid and thermal management fluid composition comprising same

Abstract

Provided are an additive for a thermal management fluid comprising a phosphate-based compound as an additive for a thermal management fluid, and a thermal management fluid composition comprising the same. Use of the additive may improve the stability of the thermal management fluid.

Description

Technical Field

[0001] This disclosure relates to an additive for thermal management fluids and a thermal management fluid composition comprising the same. Background Technology

[0002] Thermal management fluid is a fluid used to efficiently transfer and control heat, primarily in cooling and heating systems.

[0003] The function of a coolant is to lower the temperature of a heat source by absorbing heat generated from it. Substances with high thermal efficiency, low viscosity, low price, non-toxicity, chemical stability, and no corrosiveness to equipment are preferred as coolants.

[0004] As electric vehicles and other electronic products become increasingly high-performance, they generate more heat during use. Controlling this heat generation is essential to ensure smooth operation and prevent shortened product lifespan.

[0005] Immersion cooling is a cooling method used for thermal management of electronic devices and computer systems. Immersion cooling involves direct contact between the electronic device and the fluid for cooling, thus effectively removing heat compared to traditional air or water cooling methods.

[0006] [Existing Technical Documents]

[0007] [Patent Documents]

[0008] (Patent Document 1) WO WO2023-114449 A1 Summary of the Invention

[0009] Technical issues

[0010] This disclosure relates to an additive for thermal management fluids and a thermal management fluid composition comprising the same.

[0011] Technical solution

[0012] One aspect of this disclosure is as an additive for thermal management fluids, comprising a phosphate ester-based compound.

[0013] According to one embodiment, the phosphate ester compound satisfies the following chemical formula 1.

[0014] [Chemical Formula 1]

[0015]

[0016] Wherein, R is independently hydrogen or a functional group comprising 1 to 10 carbon atoms.

[0017] According to one embodiment, at least one of the R is a functional group comprising 1 to 10 carbon atoms.

[0018] According to one embodiment, the R is a functional group comprising 1 to 6 carbons, which are independent of each other.

[0019] According to one embodiment, the R further includes heteroatoms.

[0020] According to one embodiment, the heteroatom is a halogen atom.

[0021] According to one embodiment, the additive satisfies a ΔFP of at least 10°C, where ΔFP = (flash point of the fluid containing the additive) - (flash point of the fluid without the additive).

[0022] Another aspect of this disclosure, as a thermal management fluid composition, comprises a base oil and one or more phosphate ester-based compounds.

[0023] According to one embodiment, the composition can be used for immersion cooling.

[0024] According to one embodiment, the base oil is a mineral oil-based base oil.

[0025] According to one embodiment, the base oil content is at least 80 wt%.

[0026] According to one embodiment, the content of the phosphate ester compound is greater than 0 wt% and less than or equal to 10 wt%.

[0027] According to one embodiment, the composition further comprises additives.

[0028] According to one embodiment, the additive includes antioxidants, defoamers, corrosion inhibitors, detergents, dispersants, friction modifiers, abrasion resistant agents, extreme pressure additives, viscosity index improvers, pour point depressants, viscosity modifiers, or combinations thereof.

[0029] Technical effect

[0030] According to one embodiment, the application of the additive can improve the safety of the thermal management fluid. According to one embodiment, the application of the additive can help reduce the viscosity of the thermal management fluid. According to one embodiment, the application of the additive does not reduce the dielectric constant of the thermal management fluid. According to one embodiment, the thermal management fluid to which the additive is applied can be used as an immersion cooling fluid. According to one embodiment, when using the thermal management fluid for immersion cooling, the application of the additive can improve cooling efficiency, thereby reducing the amount of electricity used for cooling and potentially reducing carbon emissions. Attached Figure Description

[0031] Figure 1 This is a diagram showing the structural formula of a phosphate ester-based compound according to one embodiment. Detailed Implementation

[0032] The present disclosure will now be described in detail. However, this is only exemplary and the present disclosure is not limited to the specific embodiments described herein.

[0033] Additives for thermal management fluids

[0034] This disclosure provides an additive for thermal management fluids. The additive comprises a phosphate ester-based compound. Therefore, in this disclosure, "additive for thermal management fluids" can be used interchangeably with "phosphate ester-based additive" or "phosphate ester-based compound additive." In this disclosure, a phosphate ester-based compound refers to a compound containing a phosphate ester. Specifically, the phosphate ester-based compound can be an organophosphate ester compound. In one embodiment, the additive for thermal management fluids can be a phosphate ester-based compound. In another embodiment, the additive for thermal management fluids may contain more than one phosphate ester-based compound.

[0035] The phosphate ester-based compound can satisfy the following chemical formula 1.

[0036] [Chemical Formula 1]

[0037]

[0038] The three R groups are independent of each other. R can be hydrogen or a functional group comprising 1 to 10 carbons. Specifically, R can be hydrogen or a functional group comprising 1 to 8 carbons, and more specifically, R can be hydrogen or a functional group comprising 1 to 6 carbons. From the perspective of higher flash points, the number of carbons in the R group can be less than 8.

[0039] According to one embodiment, at least one of the three Rs may not be hydrogen. In other words, at least one of the Rs may be a functional group comprising 1 to 10 carbon atoms. Specifically, at least two of the Rs may be non-hydrogen functional groups. More specifically, all Rs may be non-hydrogen functional groups. Of course, in this case, the three Rs may also be independent of each other. More specifically, the Rs may be functional groups comprising 1 to 6 carbon atoms, independently of each other. From the perspective of improving the performance of the thermal management fluid containing the additive, the Rs may all be non-hydrogen. Specifically, the improvement in performance may include improvements in flame retardancy, electrical conductivity, corrosivity, etc.

[0040] Additionally, according to one embodiment, the total number of carbons in the compound can be 1-30. Specifically, the total number of carbons can be 1-24, more specifically, more than 1 and less than 24, more specifically, 1-21, and more specifically, 1-18. From the perspective of higher flash points, the total number of carbons can be less than 24.

[0041] For example, the functional group may be a hydrocarbon group. From a chemical stability perspective, the functional group may be an alkyl group. The functional group may be linear, branched, or cyclic. Alternatively, the functional group may include aromatic groups.

[0042] According to another embodiment, R may further include heteroatoms. Exemplarily, R may further include O, N, S, P, B, F, Cl, Br, I, or combinations thereof. Specifically, R may further include halogen atoms. In this case, R may be a halogen-substituted alkyl group. More specifically, R may further include F.

[0043] The use of the additive in thermal management fluids can increase the flash point of the fluid. While not bound by any particular theory, it is believed that the phosphate-based compounds in the additive can scavenge free radicals and form a char layer. When added to thermal management fluids, the phosphate-based compounds scavenge flammable free radicals generated by the oxidation of the base oil, thereby increasing the flash point.

[0044] According to one embodiment, the additive can satisfy a ΔFP of at least 10 (°C). Here, ΔFP refers to the flash point of the fluid containing the additive minus the flash point of the fluid without the additive. In this disclosure, the flash point of the fluid is measured using ASTM D93. The ΔFP value refers to the maximum ΔFP value when the amount of additive contained in the fluid is greater than 0 and less than or equal to 10 wt%. Specifically, the ΔFP can be 10-60, more specifically, 15-60, and even more specifically, 15-55.

[0045] The additives described above increase the flash point of thermal management fluids, thereby potentially improving safety, such as delaying thermal runaway, in systems using these fluids. Furthermore, these additives enable the use of base oils that previously had low flash points and were unsuitable for thermal management fluids, thus potentially expanding the selectivity of base oils for thermal management fluids.

[0046] Thermal management fluid composition

[0047] This disclosure provides a thermal management fluid composition comprising the aforementioned thermal management fluid additive (i.e., a phosphate ester-based additive). It should be noted that the following description of the thermal management fluid additive is applicable to the above, and repeated details may be omitted. The thermal management fluid composition possesses excellent insulating and cooling properties, and therefore can cool electronic devices through direct contact with them. In other words, the composition can be used as an immersion cooling fluid.

[0048] The composition comprises a base oil and one or more phosphate ester compounds. The base oil may include mineral oil, synthetic base oil, or a combination thereof. The mineral oil refers to oil derived from crude oil without undergoing a separate synthetic process. In this disclosure, the mineral oil may include base oils corresponding to Group I through Group III of the American Petroleum Institute (API) standards. The synthetic base oil includes, for example, polyalphaolefin (PAO) or ester base oil. In one embodiment, the base oil may include mineral oil as a major base oil and synthetic base oil as a minor base oil. In this disclosure, a major base oil refers to base oil comprising more than 50 wt% of the total base oil content. In another embodiment, the base oil may be mineral oil.

[0049] Generally speaking, PAO exhibits superior performance compared to mineral oil, but its disadvantage is its high price.

[0050] The compositions disclosed herein contain the aforementioned phosphate ester-based additives, thus, although mineral oil is used as the primary base oil, at least equivalent performance can be achieved as a thermal management fluid compared to the case using only PAO, and a relatively cheaper price is expected. On the other hand, ester base oils have excellent thermal conductivity, but due to their polarity, their insulating properties are worse than those of mineral oils, and they are susceptible to moisture due to potential hydrolysis, making them unsuitable as the primary base oil of this technology.

[0051] According to one embodiment, based on the total weight of the composition, the base oil content can be at least 80 wt%. Specifically, the base oil content can be greater than or equal to 80 wt% and less than 100 wt%. More specifically, the base oil content can be greater than or equal to 90 wt% and less than 100 wt%. Even more specifically, the base oil content can be 90 wt% to 98 wt%.

[0052] When the base oil content is low, the amount of additives, which are more expensive than the base oil, used can increase, leading to an increase in the price of the final product. Furthermore, the increased dielectric constant of the final product results in increased conductivity and decreased material compatibility (e.g., corrosion), potentially rendering it unusable as an immersion cooling fluid.

[0053] The base oils disclosed herein are not particularly limited as long as they can be used as heat management fluids or immersion cooling fluids. Furthermore, the flash point of the fluid can be increased by adding phosphate ester compounds, therefore oils with flash points lower than those used in existing heat management fluids are also considered as novel base oils.

[0054] The composition comprises one or more phosphate ester compounds. The one or more phosphate ester compounds may be compounds of the above-described chemical formula 1.

[0055] According to one embodiment, based on the total weight of the composition, the content of the phosphate ester compound can exceed 0 wt% and be less than or equal to 10 wt%. For example, the content of the compound can be 0.1-10 wt%, 0.5-10 wt%, 1-10 wt%, 2-10 wt%, 3-10 wt%, 4-10 wt%, 5-10 wt%, 0.1-9 wt%, 0.5-9 wt%, 1-9 wt%, 2-9 wt%, 3-9 wt%, 4-9 wt%, 5-9 wt%, 0.1-8 wt%, 0.5-8 wt%, 1-8 wt%, 2-8 wt%, 3-8 wt%, 4-8 wt%, 5-8 wt%, 0.1-7 wt%, 0.5-7 wt%, 1-7 wt%, 2-7 wt%, 3-7 wt%, 4-7 wt%, 5-7 wt%, 0.1-6 wt%, 0.5-6 wt%, 1-6 wt%, 2-6 wt%, 3-6 wt%, 4-6 wt%, 5-6 wt%. Specifically, the content of the compound can be 1.5-10 wt%. From the perspective of increasing the flash point, the content of the compound can be at least 1.5 wt%. When the content of the compound exceeds the above value, the flash point of the composition may be lower than that of the thermal management fluid composition without the addition of the phosphate ester compound.

[0056] The composition may further include additives other than phosphate ester compounds. These additives refer to additives different from those used in thermal management fluids, and for distinction, may also be referred to as "second additives" in this disclosure.

[0057] The additive is not particularly limited as long as it can be used to improve the physical properties of the thermal management fluid. Exemplarily, the additive may include antioxidants, defoamers, corrosion inhibitors, detergents, dispersants, friction modifiers, abrasion resistant agents, extreme pressure additives, viscosity index improvers, pour point depressants, viscosity modifiers, or any combination thereof.

[0058] According to one embodiment, the total content of the second additive, based on the total weight of the composition, can be 0-10 wt%. For example, the content can be 0.01-10 wt%, 0.05-10 wt%, 0.1-10 wt%, 0.2-10 wt%, 0.5-10 wt%, 1-10 wt%, 0.01-7 wt%, 0.05-7 wt%, 0.1-7 wt%, 0.2-7 wt%, 0.5-7 wt%, 1-7 wt%, 0.01-5 wt%, 0.05-5 wt%, 0.1-5 wt%, 0.2-5 wt%, 0.5-5 wt%, 1-5 wt%. Specifically, the content can be 0-5 wt%.

[0059] As described above, the flash point of the fluid composition is increased by adding a phosphate ester compound. Specifically, the flash point of the fluid composition containing the compound can be at least 10°C higher than that of a composition not containing the compound. More specifically, this flash point difference can be 10-60°C, further specifically 15-60°C, and even more specifically 15-55°C. In this disclosure, the flash point can be measured according to ASTM D93.

[0060] In other words, according to one embodiment, the flash point of the composition can be at least 190°C. Specifically, the flash point can be 190-250°C, and more specifically, it can be 195-250°C.

[0061] The kinematic viscosity of the fluid composition can be reduced by adding a phosphate ester compound. Specifically, the kinematic viscosity (@40°C) of the fluid composition containing the compound can be reduced by at least 1 cSt. More specifically, the kinematic viscosity can be reduced by at least 1.5 cSt.

[0062] As described above, the use of additives for thermal management fluids in this disclosure increases the flash point of the fluid, thus potentially improving safety, such as delaying thermal runaway, when applied to immersion cooling systems. Furthermore, the use of these additives reduces the viscosity of the fluid compared to the base oil, potentially reducing power consumption when applied to immersion cooling systems. These additives can be easily added to existing thermal management fluids, thus enabling a wide range of applications.

[0063] The embodiments of this disclosure are further described below with reference to specific experimental examples. The embodiments and comparative examples included in the experimental examples are only for illustrating this disclosure and do not limit the scope of the appended claims. Various changes and modifications can be made to the embodiments within the scope and technical concept of this disclosure, which will be obvious to those skilled in the art, and it is only natural that such variations and modifications fall within the scope of the appended claims.

[0064] Example

[0065] 1. Preparation of phosphate ester compounds

[0066] Prepare phosphate ester compounds (P1-P5) for the experiment. The specific chemical structures of each compound are as follows: Figure 1 As shown.

[0067] 2. Observe the changes in physical properties that occur with the addition of phosphate ester compounds.

[0068] Prepare two base oils (base oil A and base oil B). Add a specific amount of compound P1 or P2 to each base oil and observe the changes in physical properties as the compound is added. Each physical property is measured using the following equipment and / or methods.

[0069] - Closed cup flash point: ASTM D93 method

[0070] - Conductivity: Flucon Epsilon+ / IEC 60247

[0071] - Kinematic viscosity: Cannon CAV2000 / ASTM D445-01

[0072] The measurement results are shown in Table 1 below.

[0073] Table 1

[0074]

[0075] As shown in Table 1, by adding the phosphate ester-based compound of this disclosure, the flash point is increased while maintaining conductivity, and the kinematic viscosity is reduced. This reduction in kinematic viscosity can provide the beneficial effect of reducing the power consumption of the pump required to flow the fluid.

[0076] 3. Observe the flash point change based on the amount of phosphate ester compound added.

[0077] (1) Base oil A

[0078] P1-P5 were added to base oil A at various concentrations, and the flash point changes were observed according to the amount of compound added. The measurement results are shown in Table 2 below.

[0079] Table 2

[0080]

[0081] (2) Base oil B

[0082] P2-P3 were added to base oil B at various concentrations, and the flash point changes were observed according to the amount of compound added. The measurement results are shown in Table 3 below.

[0083] Table 3

[0084]

[0085] As can be seen from Tables 2 and 3, the flash point is increased compared to existing base oils by adding the phosphate ester compounds of this disclosure. In particular, for P1 to P3, the flash point is increased by more than 9°C.

[0086] In addition, as shown in Table 3, the addition of the additives disclosed herein can also improve the flash point of base oils with high flash points above 200°C.

[0087] On the other hand, referring again to Tables 2 and 3, it can be seen that the additive content with the maximum ΔFP value may vary for each additive. While not wishing to be bound by a specific theory, it is believed that this is due to the decrease in viscosity of the fluid composition with the addition of additives, thus increasing the generation of flammable oil vapors.

[0088] As confirmed from the above embodiments, the phosphate ester-based compounds of this disclosure are used as additives for thermal management fluids to improve various physical properties of the fluids, and are thus expected to be applicable to various fields.

[0089] The above description is merely an example of applying the principles of this disclosure, and other components may be included without departing from the scope of this invention.

Claims

1. An additive for thermal management fluids, comprising a phosphate ester-based compound.

2. The additive for thermal management fluids according to claim 1, wherein: The phosphate ester-based compound satisfies the following chemical formula 1. [Chemical Formula 1] Wherein, R is independently hydrogen or a functional group comprising 1 to 10 carbon atoms.

3. The additive for thermal management fluids according to claim 2, wherein: At least one of R is a functional group comprising 1 to 10 carbon atoms.

4. The additive for thermal management fluids according to claim 2, wherein: The R groups are functional groups consisting of 1 to 6 carbon atoms, which are independent of each other.

5. The additive for thermal management fluids according to claim 2, wherein: The R also contains heteroatoms.

6. The additive for thermal management fluids according to claim 5, wherein: The heteroatom is a halogen atom.

7. The additive for thermal management fluids according to claim 1, wherein: The additive satisfies a ΔFP of at least 10°C. Wherein, △FP = (flash point of the fluid containing the additive) - (flash point of the fluid without the additive).

8. A thermal management fluid composition comprising: Base oils; and One or more phosphate ester compounds.

9. The thermal management fluid composition according to claim 8, wherein: The composition can be used for immersion cooling.

10. The thermal management fluid composition according to claim 8, wherein: The base oil is a mineral oil-based base oil.

11. The thermal management fluid composition according to claim 8, wherein: The base oil content is at least 80 wt%.

12. The thermal management fluid composition according to claim 8, wherein: The content of the phosphate ester compound is greater than 0 wt% and less than or equal to 10 wt%.

13. The thermal management fluid composition according to claim 8, wherein: The composition also contains additives.

14. The thermal management fluid composition according to claim 13, wherein: The additives include antioxidants, defoamers, corrosion inhibitors, detergents, dispersants, friction modifiers, abrasion resistant agents, extreme pressure additives, viscosity index improvers, pour point depressants, viscosity modifiers, or combinations thereof.

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