Cooling medium based on perfluorinated compound

Abstract

The invention discloses a cooling medium based on a perfluorinated compound, and relates to the field of cooling media. The cooling medium comprises perfluoro-4-methyl-2-pentene serving as a core component, and the perfluoro-4-methyl-2-pentene is mixed with perfluorohexanone, perfluoro-2-methyl-2, 3-epoxypentane and a perfluoropolyether alcohol mixture containing borane functional groups according to a mass ratio. The obtained cooling medium has excellent cooling performance and chemical stability, and is suitable for high-performance electronic equipment, data centers and industrial cooling systems.

Description

Technical Field

[0001] The present invention relates to the field of cooling media, and particularly to a cooling media based on perfluorinated compounds. Background Art

[0002] In the fields of modern high-performance electronic devices, data centers, industrial production, and new energy vehicles, the problem of thermal management has become increasingly prominent. With the improvement of computing power, the heat generated by central processing units (CPUs), graphics processing units (GPUs), and power semiconductor components (such as IGBTs, MOSFETs) during operation has increased significantly. The efficiency of traditional air-cooling methods can no longer meet the heat dissipation requirements of high-power density devices.

[0003] Currently, the mainstream heat dissipation methods for electronic devices mainly include air-cooling, liquid-cooling, and phase change cooling, among which:

[0004] Air-cooling technology:

[0005] The air-cooling system removes the heat generated by the device through forced air flow. Its advantages are low cost and simple structure. However, in high-power application scenarios, it has the following deficiencies: Limited heat dissipation efficiency in the cooling media field: The specific heat capacity of air is small (about 1.0 kJ / kg·K), and its heat transfer capacity is limited, making it difficult to meet the heat dissipation requirements of high-power devices; Large thermal resistance in the cooling media field: In the air-cooling system, the heat transfer efficiency between the heat sink and air is low, resulting in prominent local hot spots problems; Increased noise and energy consumption in the cooling media field: The use of high-power fans leads to increased noise, and the power usage effectiveness (PUE) is relatively high (usually > 1.5) during large-scale deployment.

[0006] Traditional liquid-cooling technology:

[0007] The liquid-cooling technology uses a coolant with a high specific heat capacity to circulate and remove heat, including direct liquid-cooling (DLC) and indirect liquid-cooling (using cooling plates or cooling channels). The heat dissipation capacity of the liquid-cooling technology is better than that of air-cooling, but it has the following problems: Safety issues of the heat-conducting medium in the cooling media field: Conventional water-based or oil-based coolants have problems such as high electrical conductivity and easy corrosion, posing challenges to the reliability of electronic components; High maintenance cost in the cooling media field: The replacement of the coolant, the maintenance of the circulation pump, and the risk of liquid leakage increase the operation and maintenance difficulty; Insufficient phase change ability in the cooling media field: Traditional liquid-cooling only relies on the sensible heat transfer of the liquid and cannot fully utilize the latent heat effect of phase change cooling.

[0008] Phase change cooling technology:

[0009] Phase-Change Cooling utilizes the characteristic that a large amount of heat is absorbed during the vaporization of a liquid for efficient heat dissipation, mainly including two forms: Evaporative Cooling in the field of cooling media: The coolant vaporizes in the heating area and is then recycled through the condensation cycle; Immersion Cooling in the field of cooling media: Electronic components are directly immersed in a coolant with a low boiling point, and the temperature is reduced by absorbing heat through phase change.

[0010] Compared with traditional air cooling and liquid cooling, phase-change cooling can significantly improve the heat transfer efficiency, and can achieve fanless heat dissipation, reducing noise and energy consumption. However, the existing phase-change coolants mainly have the following problems:

[0011] Non-azeotropic mixtures in the field of cooling media are prone to separation: Most of the existing coolants are multi-component mixtures with a wide boiling point range, and the composition is likely to change after long-term use, affecting stability; Large temperature glide in the field of cooling media: The composition of non-azeotropic coolants changes significantly during the gasification process, resulting in unstable working temperatures; Limited safety of some coolants in the field of cooling media: Some fluoride coolants have high ozone depletion potential (ODP) and global warming potential (GWP), not meeting modern environmental protection requirements. Summary of the Invention

[0012] To solve these problems, the present invention provides a cooling medium based on perfluorinated compounds, which is composed of a specific ratio of perfluoro-4-methyl-2-pentene, perfluorohexanone, and perfluoro-2-methyl-2,3-epoxypentane. The cooling medium of the present invention is superior to the existing coolants in terms of efficient heat dissipation, stability, safety, and environmental protection, and is applicable to fields such as data centers, high-power electronic devices, industrial cooling systems, and thermal management of new energy vehicle batteries.

[0013] The specific solutions are as follows:

[0014] A cooling medium based on perfluorinated compounds, characterized in that the cooling medium comprises the following components, by mass:

[0015] 10 - 40 parts of perfluoro-4-methyl-2-pentene;

[0016] 30 - 60 parts of perfluorohexanone;

[0017] 10 - 30 parts of perfluoro-2-methyl-2,3-epoxypentane;

[0018] A perfluoropolyether alcohol mixture containing a borane functional group: 0.05 - 0.5 parts.

[0019] Furthermore, the preparation method of the perfluoropolyether alcohol mixture containing a borane functional group is as follows:

[0020] In a three-necked flask equipped with a magnetic stir bar, a thermometer and a constant-pressure dropping funnel, nitrogen is introduced to displace air for 30 - 100 minutes, and 20 - 30 parts of trimethoxysilane are added. The flask is placed in a low-temperature bath at -60 to -78 °C, and 22 - 33 parts of boron tribromide are slowly added dropwise. After the addition is complete, the mixture is stirred at -60 to -78 °C for 1 hour, and then the temperature is raised to room temperature and the reaction is continued for 2 - 4 hours. After the reaction is completed, distillation is carried out under reduced pressure, and the fraction at 60 - 65 °C / 20 mmHg is collected to obtain Intermediate 1;

[0021] 10 - 20 parts of perfluoropolyether alcohol and 10 - 20 parts of pyridine are added to a three-necked flask. After stirring evenly, 2.8 - 5.6 parts of Intermediate 1 are added, and the mixture is heated to 70 - 80 °C and refluxed for 6 - 10 hours. After the reaction is completed, the product is treated, and then added to methanol. Sodium hydroxide solution is added for hydrolysis to remove the protection, and a perfluoropolyether alcohol mixture containing borane functional groups is obtained through treatment.

[0022] Furthermore, the physical properties of the cooling medium satisfy the following parameter ranges:

[0023] Boiling point range: 35 °C to 60 °C;

[0024] Latent heat of vaporization: ≥100 kJ / kg;

[0025] Dielectric constant: ≤2.0;

[0026] Surface tension: ≤20 mN / m.

[0027] Furthermore, the cooling medium is prepared by the following process method:

[0028] (1) Weigh 10 - 40 parts of perfluoro-4-methyl-2-pentene, 30 - 60 parts of perfluorohexanone, 10 - 30 parts of perfluoro-2-methyl-2,3-epoxypentane and 0.05 - 0.5 part of perfluoropolyether alcohol containing borane functional groups by mass;

[0029] (2) Stir and mix the above components at a set temperature and pressure, with a stirring speed of 100 - 500 r / min for a duration of 0.5 - 2 h to make the components evenly dispersed;

[0030] (3) Let the obtained mixture stand at -10 to 5 °C to ensure the stability of the system;

[0031] (4) Filter through a microporous membrane to remove impurities to obtain the cooling medium.

[0032] Furthermore, in step (2), the stirring and mixing temperature is 20 - 30 °C and the pressure is 0.1 - 0.2 MPa.

[0033] Furthermore, in step (3), the standing time is 2 - 12 h.

[0034] Further, in the step (4), the pore size of the microfiltration membrane is 0.1 - 0.5 μm.

[0035] Further, the cooling medium is applied to the following equipment:

[0036] Data center processors;

[0037] Supercomputers;

[0038] High - power power electronic components;

[0039] Laser equipment;

[0040] New energy vehicle battery systems.

[0041] Reaction mechanism:

[0042] In the first step, boron tribromide, as a strong Lewis acid, its boron atom attacks the methoxy oxygen atom of trimethoxysilane, and through rearrangement, (CH3O)3Si - BBr2 is formed.

[0043] In the second step, under the action of pyridine, perfluoropolyether alcohol forms an oxygen anion, which attacks the methoxy group on the silicon atom in \((CH3O)3Si BBr2\) to generate PFPE - O - Si(OMe)2 - BBr2.

[0044] In the third step, under the action of methanol and sodium hydroxide, the hydroxide ion attacks the bromine atom on the boron atom, and through nucleophilic addition and elimination reactions, PFPE - O - Si(OMe)2 - B(OH)2 is obtained.

[0045] Beneficial effects

[0046] 1. Performance improvement: The perfluoropolyether alcohol containing borane functional groups, as a synergist, combines the characteristics of perfluoropolyether alcohol and borane functional groups, can significantly increase the latent heat of vaporization and cooling efficiency of the cooling medium, reduce temperature slip, and at the same time enhance the stability of the system.

[0047] 2. Excellent physical properties: The cooling medium of the present invention has a suitable boiling point range, a relatively high latent heat of vaporization, a low dielectric constant and a low surface tension, can well meet the cooling requirements of electronic devices, etc., and improve electrical safety.

[0048] 3. Simple preparation method: The preparation method only includes two main steps of mixing and post - treatment, with simple operation and easy industrial production. Specific implementation mode

[0049] Embodiments of the present invention will be described in detail below. It should be noted that the terms and words used in this specification and claims should not be construed in their ordinary or dictionary meanings, but should be interpreted in accordance with the principle that the inventor can appropriately define the term concept to preferably describe his invention, in a sense and concept consistent with the technical idea of the present invention. Therefore, it should be understood that the compositions described in the embodiments listed herein are only the most preferred embodiments of the present invention, not all of the technical ideas of the present invention, and various equivalents and variations that can replace them may exist at the time of application.

[0050] Throughout the specification, when a component "comprises" a component, it may mean that other components are further included, rather than excluding other components, unless otherwise stated to the contrary.

[0051] In addition, descriptions of limiting or increasing components may apply to any invention, not limited to any specific invention, unless otherwise stated.

[0052] In addition, in the specification and claims of the present invention, singular expressions include plural expressions, unless otherwise stated.

[0053] In addition, in the specification and claims of the present invention, "or" includes "and", unless otherwise stated. Therefore, "comprising A or B" means all three cases: comprising A, comprising B, and comprising both A and B.

[0054] In addition, all numerical ranges include the numerical values at both ends and all intermediate values therebetween, unless explicitly stated to exclude them.

[0055] Example 1

[0056] Raw material ratio:

[0057] Perfluoro-4-methyl-2-pentene: 15 g

[0058] Perfluorohexanone: 50 g

[0059] Perfluoro-2-methyl-2,3-epoxypentane: 25 g

[0060] Perfluoropolyether alcohol mixture containing borane functional groups: 0.05 g

[0061] In this example, the preparation method of the perfluoropolyether alcohol mixture containing borane functional groups is as follows: 1) Nitrogen is introduced into a three-necked flask to displace air for 40 min, and 22 g of trimethoxysilane is added; 2) The flask is placed in a low-temperature bath at -70 °C, and 25 g of boron tribromide is slowly added dropwise. After the addition is complete, it is stirred at -70 °C for 1 h; 3) The temperature is raised to room temperature, and the reaction is continued for 3 h. After the reaction is completed, vacuum distillation is carried out, and the fraction at 60 °C / 20 mmHg is collected to obtain Intermediate 1; 4) 12 g of perfluoropolyether alcohol and 12 g of pyridine are added to another three-necked flask. After stirring evenly, 3.0 g of Intermediate 1 is added, and the mixture is heated to 75 °C and refluxed for 8 h; 5) After the reaction is completed, the product is added to methanol, and a sodium hydroxide solution is added for hydrolysis and deprotection, and the perfluoropolyether alcohol mixture containing borane functional groups is obtained after treatment.

[0062] Process steps:

[0063] 1. Weigh the above components according to the ratio.

[0064] 2. Stir and mix at 25 °C and 0.15 MPa at 300 r / min for 1 h to uniformly disperse the components.

[0065] 3. Let the obtained mixture stand at 0 °C for 6 h to ensure the stability of the system.

[0066] 4. Filter with a microporous filter membrane with a pore size of 0.2 μm to remove impurities and obtain the cooling medium.

[0067] Example 2

[0068] Raw material ratio:

[0069] Perfluoro-4-methyl-2-pentene: 25 g

[0070] Perfluorohexanone: 40 g

[0071] Perfluoro-2-methyl-2,3-epoxypentane: 20 g

[0072] Perfluoropolyether alcohol mixture containing borane functional groups: 0.2 g

[0073] In this example, the preparation method of a perfluoropolyether alcohol mixture containing borane functional groups: 1) Nitrogen is introduced into a three-necked flask to displace air for 100 min, and 30 g of trimethoxysilane is added; 2) The flask is placed in a low-temperature bath at -78 °C, and 33 g of boron tribromide is slowly added dropwise. After the addition is complete, it is stirred at -78 °C for 1 h; 3) The temperature is raised to room temperature, and the reaction is continued for 4 h. After the reaction is completed, vacuum distillation is carried out, and the fraction at 65 °C / 20 mmHg is collected to obtain Intermediate 1; 4) 15 g of perfluoropolyether alcohol and 18 g of pyridine are added to another three-necked flask. After stirring evenly, 5.6 g of Intermediate 1 is added, and the mixture is heated to 80 °C and refluxed for 10 h; 5) After the reaction is completed, the product is added to methanol, and a sodium hydroxide solution is added for hydrolysis and deprotection. After treatment, a perfluoropolyether alcohol mixture containing borane functional groups is obtained.

[0074] Process steps:

[0075] 1. Weigh the above components according to the ratio.

[0076] 2. Stir and mix at 30 °C and 0.2 MPa at 400 r / min for 2 h to uniformly disperse the components.

[0077] 3. Let the obtained mixture stand at 5 °C for 12 h to ensure the stability of the system.

[0078] 4. Filter with a microporous membrane with a pore size of 0.5 μm to remove impurities and obtain a cooling medium.

[0079] Example 3

[0080] Raw material ratio:

[0081] Perfluoro-4-methyl-2-pentene: 40 g

[0082] Perfluorohexanone: 30 g

[0083] Perfluoro-2-methyl-2,3-epoxypentane: 10 g

[0084] Perfluoropolyether alcohol mixture containing borane functional groups: 0.4 g

[0085] In this example, the preparation method of the perfluoropolyether alcohol mixture containing borane functional groups is as follows: 1) Nitrogen is introduced into a three-necked flask to displace air for 60 min, and 25 g of trimethoxysilane is added; 2) The flask is placed in a low-temperature bath at -65 °C, and 28 g of boron tribromide is slowly added dropwise. After the addition is completed, it is stirred at -65 °C for 1 h; 3) The temperature is raised to room temperature, and the reaction is continued for 2 h. After the reaction is completed, vacuum distillation is carried out, and the fraction at 62 °C / 20 mmHg is collected to obtain Intermediate 1; 4) 18 g of perfluoropolyether alcohol and 14 g of pyridine are added to another three-necked flask. After stirring evenly, 4.5 g of Intermediate 1 is added, and the mixture is heated to 70 °C and refluxed for 6 h; 5) After the reaction is completed, the product is added to methanol, and a sodium hydroxide solution is added for hydrolysis and deprotection, and the perfluoropolyether alcohol mixture containing borane functional groups is obtained after treatment.

[0086] Process steps:

[0087] 1. Weigh the above components according to the ratio.

[0088] 2. Under the conditions of 20 °C and 0.1 MPa, stir and mix at 100 r / min for 0.5 h to uniformly disperse the components.

[0089] 3. Let the obtained mixture stand at -10 °C for 2 h to ensure the stability of the system.

[0090] 4. Filter with a microporous filter membrane with a pore size of 0.1 μm to remove impurities and obtain the cooling medium.

[0091] Example 4

[0092] Raw material ratio:

[0093] Perfluoro-4-methyl-2-pentene: 10 g

[0094] Perfluorohexanone: 60 g

[0095] Perfluoro-2-methyl-2,3-epoxypentane: 30 g

[0096] Perfluoropolyether alcohol mixture containing borane functional groups: 0.5 g

[0097] In this example, the preparation method of the perfluoropolyether alcohol mixture containing borane functional groups is as follows: 1) Nitrogen is introduced into a three-necked flask to displace air for 30 min, and 20 g of trimethoxysilane is added; 2) The flask is placed in a low-temperature bath at -60 °C, and 22 g of boron tribromide is slowly added dropwise. After the addition is complete, the mixture is stirred at -60 °C for 1 h; 3) The temperature is raised to room temperature, and the reaction is continued for 3 h. After the reaction is completed, vacuum distillation is carried out, and the fraction at 60 °C / 20 mmHg is collected to obtain Intermediate 1; 4) 10 g of perfluoropolyether alcohol and 10 g of pyridine are added to another three-necked flask. After stirring evenly, 2.8 g of Intermediate 1 is added, and the mixture is heated to 78 °C and refluxed for 9 h; 5) After the reaction is completed, the product is added to methanol, and a sodium hydroxide solution is added for hydrolysis and deprotection, and the perfluoropolyether alcohol mixture containing borane functional groups is obtained after treatment.

[0098] Process steps:

[0099] 1. Weigh the above components according to the ratio.

[0100] 2. Stir and mix at 28 °C and 0.12 MPa at 500 r / min for 1.5 h to uniformly disperse the components.

[0101] 3. Let the obtained mixture stand at -5 °C for 8 h to ensure the stability of the system.

[0102] 4. Filter with a microporous filter membrane with a pore size of 0.3 μm to remove impurities and obtain the cooling medium.

[0103] Comparative Example 1

[0104] In this example, only the perfluoropolyether alcohol mixture containing borane functional groups is not added during the preparation of the cooling medium, and the rest is the same as in Example 1.

[0105] Comparative Example 2

[0106] In this example, only trimethoxysilane is not added during the preparation of the perfluoropolyether alcohol mixture containing borane functional groups, and the rest is the same as in Example 1.

[0107] Comparative Example 3

[0108] In this example, only boron tribromide is not added during the preparation of the perfluoropolyether alcohol mixture containing borane functional groups, and the rest is the same as in Example 1.

[0109] Test method:

[0110] 1) Vaporization latent heat test (heat transfer capacity)

[0111] Test method: Use a differential scanning calorimeter (DSC) to measure the vaporization latent heat of the coolant at 40 °C under standard pressure.

[0112] Take 10 mL of the coolant in an aluminum crucible and heat it up within the temperature range of 30°C to 70°C to measure the change in the phase change enthalpy of the coolant. Calculate the latent heat of vaporization per unit mass (kJ / kg) through the heat flow curve.

[0113] Table 1: Test Results of the Latent Heat of Vaporization for Examples and Comparative Examples

[0114] Latent heat of vaporization (kJ / kg) Example 1 118.5 Example 2 119.3 Example 3 120.0 Example 4 120.4 Comparative Example 1 110.4 Comparative Example 2 115.6 Comparative Example 3 115.2

[0115] 2) Temperature Slip Test (Phase Change Stability)

[0116] Test Method: Use a precision boiling point meter (Anton Paar DMA 4500) to measure the vapor-liquid equilibrium of the coolant. Within the working pressure range of 68 - 137 kPa, measure the bubble point (when liquid starts to vaporize) and dew point (when vapor starts to condense) temperatures of the coolant, and calculate the temperature slip value.

[0117] Table 2: Test Results of the Temperature Slip for Examples and Comparative Examples

[0118] Bubble point (°C) Dew point (°C) Temperature slip (°C) Example 1 38.5 39.0 0.5 Example 2 38.7 39.1 0.4 Example 3 39.2 39.6 0.4 Example 4 39.4 39.7 0.3 Comparative Example 1 35.6 36.7 1.1 Comparative Example 2 36.6 37.3 0.7 Comparative Example 3 36.8 37.4 0.6

[0119] 3) Electrical Insulation Performance Test

[0120] Dielectric Constant Test: Use an LCR precision bridge (Agilent 4284A) to measure the dielectric constant (ε) of the coolant within the frequency range of 1 kHz to 1 MHz. Take air (ε≈1.0006) as the reference and calculate the relative dielectric constant of the coolant.

[0121] Volume Resistivity Test: Use a high resistance meter (Keithley 6517B) to measure the volume resistivity (Ω·mm) of the coolant under a 1000 V DC voltage.

[0122] Table 3: Test Results of the Electrical Insulation Performance for Examples and Comparative Examples

[0123] Dielectric constant (ε) Volume resistivity (Ω·mm) Example 1 1.97 4.4×1015 Example 2 1.96 4.6×1015 Example 3 1.95 4.6×1015 Example 4 1.95 4.7×1015 Comparative Example 1 2.04 3.8×1015 Comparative Example 2 2.00 4.0×1015 Comparative Example 3 1.99 4.1×1015

[0124] The test results fully prove that the cooling medium of the present invention has: high latent heat of vaporization to improve the cooling capacity; low temperature slip to ensure long-term stability; and better electrical insulation, suitable for high-power devices.

[0125] Therefore, the coolant of the present invention has significant advantages in the field of heat dissipation for high-performance electronic devices and is suitable for application scenarios such as data centers, supercomputers, and new energy vehicles.

[0126] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any appropriate manner without conflict. To avoid unnecessary repetition, the present invention will not separately describe various possible combination manners.

[0127] Furthermore, any combinations can be made among various different embodiments of the present invention, as long as they do not violate the idea of the present invention, and they should also be regarded as the content disclosed by the present invention.

Claims

1. A cooling medium based on perfluorinated compounds, characterized in that, The cooling medium is prepared by the following process method: (1) Weigh 10 - 40 parts by mass of perfluoro-4-methyl-2-pentene, 30 - 60 parts of perfluoromethyl isopropyl ketone, 10 - 30 parts of perfluoro-2-methyl-2,3-epoxypentane, and 0.05 - 0.5 parts of perfluoropolyether alcohol containing borane functional groups; (2) Stir and mix the above components at a set temperature and pressure, with a stirring speed of 100 - 500 r / min for a duration of 0.5 - 2 h to make the components evenly dispersed; (3) Let the obtained mixture stand at -10 - 5 °C to ensure the stability of the system; (4) Filter through a microporous membrane to remove impurities to obtain the cooling medium; The perfluoropolyether alcohol mixture containing borane functional groups is prepared by reacting trimethoxysilane, boron tribromide, perfluoropolyether alcohol, and pyridine.

2. The cooling medium based on perfluorinated compounds according to claim 1, wherein: The preparation method of the perfluoropolyether alcohol mixture containing borane functional groups is as follows: In a three-necked flask equipped with a magnetic stirrer, a thermometer, and a constant-pressure dropping funnel, introduce nitrogen to displace air for 30 - 100 minutes, and add 20 - 30 parts of trimethoxysilane; place the flask in a low-temperature bath at -60 to -78 °C, slowly dropwise add 22 - 33 parts of boron tribromide, stir at -60 to -78 °C for 1 hour after the addition is complete, and then raise the temperature to room temperature and continue the reaction for 2 - 4 hours; after the reaction is completed, perform vacuum distillation and collect the fraction at 60 - 65 °C / 20 mmHg to obtain intermediate 1; Add 10 - 20 parts of perfluoropolyether alcohol and 10 - 20 parts of pyridine to the three-necked flask, stir evenly, then add 2.8 - 5.6 parts of intermediate 1, heat to 70 - 80 °C and reflux for 6 - 10 hours; after the reaction is completed, perform post-treatment, then add the product to methanol, add sodium hydroxide solution for hydrolysis and deprotection, and obtain the perfluoropolyether alcohol mixture containing borane functional groups after treatment.

3. The cooling medium based on perfluorinated compounds according to claim 1, wherein: The physical properties of the cooling medium meet the following parameter ranges: Boiling point range: 35 °C - 60 °C; Latent heat of vaporization: ≥100 kJ / kg; Dielectric constant: ≤2.0; Surface tension: ≤20 mN / m.

4. A cooling medium based on perfluorinated compounds according to claim 1, characterized in that: In step (2), the stirring and mixing temperature is 20 - 30 °C and the pressure is 0.1 - 0.2 MPa.

5. A cooling medium based on perfluorinated compounds according to claim 1, characterized in that: In step (3), the standing time is 2 - 12 h.

6. The cooling medium based on perfluorinated compounds according to claim 1, characterized in that: In step (4), the pore size of the microporous membrane is 0.1 - 0.5 μm.

7. A cooling medium based on perfluorinated compounds according to any one of claims 1-6, characterized in that: The cooling medium is applied to the following equipment: Data center processors; Supercomputers; High-power power electronic components; Laser devices; New energy vehicle battery systems.