Flexible phase change energy storage material constructed based on oil-in-oil emulsification system and preparation method of flexible phase change energy storage material

Abstract

The invention discloses a flexible phase change energy storage material constructed based on an oil-in-oil emulsification system and a preparation method thereof, and belongs to the field of energy storage materials, the flexible phase change energy storage material constructed based on the oil-in-oil emulsification system comprises a continuous phase, a dispersed phase and an auxiliary agent; the continuous phase comprises hydrogen-containing silicone oil and vinyl silicone oil; the dispersed phase is a phase change substance; the auxiliaries comprise an emulsifier and a catalyst. The flexible phase-change energy storage material is prepared through an oil-in-oil emulsification system, hydrogen-containing silicone oil and vinyl silicone oil are adopted as a continuous phase, a phase-change substance is adopted as a dispersed phase, and the flexible phase-change material with a bean-pod-shaped structure is finally formed by using high-speed emulsification and silicone oil crosslinking curing technologies. The phase change energy storage material disclosed by the invention has excellent flexibility, thermal stability and leak-proof performance, is suitable for various energy storage application scenes, and has the advantages of simple and easily-controlled reaction process, short production period and low production cost.

Description

Technical Field

[0001] The present invention belongs to the field of energy storage materials, and relates to a flexible phase change energy storage material constructed based on an oil-in-oil emulsion system and a preparation method thereof. Background Art

[0002] Phase change energy storage materials are of great significance in alleviating the imbalance between energy supply and demand because they can store a large amount of renewable and sustainable thermal energy in a reversible manner. Phase change energy storage materials exhibit four prominent advantages: energy storage, energy conservation, temperature regulation, and temperature control management, and have been widely used in the fields of thermal energy storage and thermal management.

[0003] Common phase change energy storage materials include paraffin wax, higher fatty acids and their derivatives. However, these materials have the following problems in practical applications:

[0004] Liquid leakage problem: Traditional phase change materials are prone to liquid leakage during the solid-liquid phase change process, affecting service life and safety.

[0005] Strong rigidity and lack of flexibility: Most phase change materials show strong rigidity in the solid state and are difficult to adapt to devices or scenarios with complex shapes.

[0006] Poor thermal cycle stability: After multiple thermal cycles, some phase change materials will undergo phase separation or performance degradation.

[0007] In the prior art, the above problems are usually solved by embedding phase change materials into inorganic porous materials (such as silica aerogel) or organic polymer matrices. However, these methods have limitations such as complex preparation processes, insufficient flexibility, and high costs. Therefore, there is currently a lack of a phase change energy storage material with simple preparation, excellent performance, and flexibility. Summary of the Invention

[0008] The purpose of the present invention is to provide a flexible phase change energy storage material constructed based on an oil-in-oil emulsion system and a preparation method thereof, which solves the problem that there is currently a lack of a phase change energy storage material with simple preparation, excellent performance, and flexibility.

[0009] The technical solution adopted by the present invention is as follows:

[0010] A flexible phase change energy storage material constructed based on an oil-in-oil emulsion system, comprising a continuous phase, a dispersed phase, and an additive; the continuous phase includes hydrogen-containing silicone oil and vinyl silicone oil; the dispersed phase is a phase change substance; the additive includes an emulsifier and a catalyst.

[0011] Based on the above formula, the present invention further utilizes high-speed emulsification and silicone oil cross-linking and curing technologies to finally form a flexible phase change material with a pod-like structure. The phase change substance is dispersed in a discontinuous state, greatly improving the flexibility of the material and making it suitable for various complex application scenarios; the phase change substance of the present invention is completely wrapped by the silicone matrix, fundamentally solving the performance defect of liquid leakage during the solid-liquid phase change process of the phase change substance.

[0012] In the present invention, hydrogen-containing silicone oil and vinyl silicone oil are used as the main components of the continuous phase. The Si-Vi functional group in the vinyl silicone oil reacts with the Si-H bond in the hydrogen-containing silicone oil to form a Si-C bond under the action of a catalyst such as a platinum catalyst, thereby constructing a three-dimensional cross-linked network structure, which can adjust the hardness, elasticity and flexibility of the material; the emulsifier is used to stabilize the oil-in-oil emulsion system and prevent phase separation between the dispersed phase and the continuous phase; the catalyst (such as a platinum catalyst) is used to accelerate the cross-linking reaction between the hydrogen-containing silicone oil and the vinyl silicone oil and promote the formation of a three-dimensional network structure; during the emulsification process, the phase change substance is wrapped in the continuous phase to form tiny droplets, and these droplets are fixed in the continuous phase to form a structure similar to a pod. This structure not only improves the dispersion uniformity of the phase change substance but also enhances the mechanical properties and thermal stability of the material.

[0013] Further, the phase change substance includes at least one of paraffin alkane C n H 2n+2 , higher fatty acid C n H 2n COOH, higher fatty alcohol C n H 2n OH, polyethylene glycol HO(CH2CH2O) n H, where n = 12 - 32.

[0014] Further, the hydrogen-containing silicone oil has a Si-H functional group, and the Si-H content is 0.5 mmol / g - 5 mmol / g.

[0015] Further, the vinyl silicone oil has a Si-Vi functional group, and the Si-Vi content is 0.2 mmol / g - 3 mmol / g.

[0016] Further, the molar ratio of the Si-H functional group in the hydrogen-containing silicone oil to the Si-Vi functional group in the vinyl silicone oil is 1 - 1.5:1.

[0017] Further, the emulsifier is at least one of sorbitan monooleate, sorbitan trioleate, polysorbate 80; the dosage of the emulsifier is 2% - 5% of the mass of the phase change substance.

[0018] Further, the catalyst is a platinum catalyst, and the platinum catalyst includes at least one of hexamethyldisilazane platinates, chloroplatinic acid, and platinum carbon catalyst; the dosage of the platinum catalyst is 0.001% to 0.01% of the sum of the masses of the hydrogen-containing silicone oil and the vinyl silicone oil.

[0019] Further, the ratio of the mass of the phase change material to the total mass of the hydrogen-containing silicone oil and the vinyl silicone oil is 1:0.7 to 5.

[0020] A preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system includes the following steps: adding a hydrogen-containing silicone oil, a vinyl silicone oil, and an emulsifier into a high-speed disperser, with a stirring speed of 2000 to 8000 rpm. After heating to 20 to 80 °C, under high-speed dispersion, slowly add the phase change material in a molten state, and keep stirring for 0.5 to 3 h to form a stable oil-in-oil emulsion; add a catalyst to the oil-in-oil emulsion, stir evenly, then pour the emulsion into a mold, and cure at 20 to 100 °C for 0.5 to 24 h to obtain the flexible phase change energy storage material. The flexible phase change energy storage material is a pod-shaped flexible phase change material.

[0021] The present invention uses a hydrogen-containing silicone oil and a vinyl silicone oil as the continuous phase, and phase change materials such as paraffin alkanes, higher fatty acids, higher fatty alcohols, and polyethylene glycols as the dispersed phase, and utilizes high-speed emulsification and silicone oil cross-linking curing technologies to finally form a flexible phase change material with a pod-shaped structure. The phase change energy storage material of the present invention has excellent flexibility, thermal stability, and anti-leakage performance, and is suitable for a variety of energy storage application scenarios.

[0022] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows:

[0023] 1. The phase change material in the flexible phase change energy storage material based on the oil-in-oil emulsion system of the present invention is completely wrapped by the silicone matrix, fundamentally solving the performance defect of liquid leakage during the solid-liquid phase change process of the phase change material;

[0024] 2. The phase change energy storage material of the present invention has a pod-shaped structure, and the phase change material is dispersed in a discontinuous state, greatly improving the flexibility of the material and being suitable for various complex application scenarios;

[0025] 3. The phase change energy storage material of the present invention adopts an oil-in-oil emulsion system and a silicone oil cross-linking curing technology, and the process is simple and easy to implement, and is easy to industrialize. Description of the Drawings

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings, where:

[0027] Figure 1 is the DSC curve of the product obtained in Example 1;

[0028] Figure 2 is the mechanical property curve of the product obtained in Example 1. Detailed implementation manners

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the following further details the present invention in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Usually, the components of the embodiments of the present invention described and shown in the accompanying drawings herein can be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present invention.

[0031] It should be noted that relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the presence of additional identical elements in the process, method, article or device including the said element.

[0032] The features and performance of the present invention will be further described in detail below in conjunction with the embodiments.

[0033] A flexible phase change energy storage material based on an oil-in-oil emulsion system, comprising a continuous phase, a dispersed phase and an additive; the continuous phase comprises hydrogen-containing silicone oil and vinyl silicone oil; the dispersed phase is a phase change substance; the additive comprises an emulsifier and a catalyst.

[0034] The phase change substance comprises at least one of paraffin alkane C n H 2n+2 , higher fatty acid C n H 2n COOH, higher fatty alcohol C n H 2n OH, polyethylene glycol HO(CH2CH2O) n H, where n = 12 - 32.

[0035] The hydrogen-containing silicone oil has an Si-H functional group, and the Si-H content is 0.5 mmol / g - 5 mmol / g.

[0036] The vinyl silicone oil has an Si-Vi functional group, and the Si-Vi content is 0.2 mmol / g - 3 mmol / g.

[0037] The molar ratio of the Si-H functional group in the hydrogen-containing silicone oil to the Si-Vi functional group in the vinyl silicone oil is 1 - 1.5:1.

[0038] The emulsifier is at least one of sorbitan monooleate, sorbitan trioleate, polysorbate 80; the dosage of the emulsifier is 2% - 5% of the mass of the phase change substance.

[0039] The catalyst is a platinum catalyst, and the platinum catalyst comprises at least one of hexamethyldisilazane platinate, chloroplatinic acid, platinum-carbon catalyst; the dosage of the platinum catalyst is 0.001% - 0.01% of the sum of the masses of the hydrogen-containing silicone oil and the vinyl silicone oil.

[0040] The ratio of the mass of the phase change substance to the total mass of the hydrogen-containing silicone oil and the vinyl silicone oil is 1:0.7 - 5.

[0041] A preparation method of the flexible phase change energy storage material based on an oil-in-oil emulsion system comprises the following steps: adding the hydrogen-containing silicone oil, vinyl silicone oil, and emulsifier into a high-speed disperser, with a stirring speed of 2000 - 8000 rpm, heating to 20 - 80 °C, and then slowly adding the phase change substance in a molten state under high-speed dispersion, maintaining stirring for 0.5 - 3 h to form a stable oil-in-oil emulsion; adding the catalyst into the oil-in-oil emulsion, stirring evenly, pouring the emulsion into a mold, and curing at 20 - 100 °C for 0.5 - 24 h to obtain the flexible phase change energy storage material. The flexible phase change energy storage material is a pod-shaped flexible phase change material.

[0042] The present invention uses hydrogen-containing silicone oil and vinyl silicone oil as the continuous phase, and phase change materials such as paraffin alkane, higher fatty acid, higher fatty alcohol, polyethylene glycol, etc. as the dispersed phase. By using high-speed emulsification and silicone oil cross-linking and curing technologies, a flexible phase change material with a pod-like structure is finally formed. The phase change energy storage material of the present invention has excellent flexibility, thermal stability and anti-leakage performance, and is suitable for a variety of energy storage application scenarios.

[0043] Example 1

[0044] A preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system provided by a specific embodiment of the present invention includes the following steps:

[0045] Add 37.5 g of hydrogen-containing silicone oil (Si-H content is 2 mmol / g), 62.5 g of vinyl silicone oil (Si-Vi content is 1 mmol / g), and 4 g of sorbitan monooleate to a high-speed disperser. After heating to 50 °C, slowly add 100 g of octadecane C in a molten state under high-speed dispersion (rotation speed 4000 rpm). 18 H 38 Keep stirring for 1 h to form a stable oil-in-oil emulsion; add 0.005 g of hexamethyldisilazane platin ate to the emulsion, stir evenly, then pour the emulsion into a mold, and cure at 60 °C for 4 h to obtain a flexible phase change energy storage material.

[0046] The product prepared in this example is a white film-like solid. The DSC spectrum is as Figure 1 shown. The phase transition point of the flexible phase change energy storage film prepared in Example 1 is about 31.2 °C during the heating process, and the phase change enthalpy reaches 113.3 J / g; the mechanical property test diagram of the flexible phase change energy storage film prepared in Example 1 is as Figure 2 shown. The elongation at break of the flexible phase change energy storage film prepared in Example 1 is 294% and the breaking stress is 2.12 MPa in the tensile experiment.

[0047] Example 2

[0048] A preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system provided by this example includes the following steps:

[0049] Add 25 g of hydrogen-containing silicone oil (Si-H content is 0.5 mmol / g), 50 g of vinyl silicone oil (Si-Vi content is 0.2 mmol / g), and 2 g of sorbitan trioleate to a high-speed disperser. After heating to 80 °C, slowly add 100 g of polyethylene glycol HO(CH2CH2O) in a molten state under high-speed dispersion (rotation speed 2000 rpm). 20Maintain stirring for 0.5 h to form a stable oil-in-oil emulsion; add 0.075 g of chloroplatinic acid to the emulsion, stir evenly, then pour the emulsion into a mold, and cure it at 100 °C for 0.5 h to obtain a flexible phase change energy storage material.

[0050] Example 3

[0051] A preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system provided in this example includes the following steps:

[0052] Add 200 g of hydrogen-containing silicone oil (Si-H content is 5 mmol / g), 300 g of vinyl silicone oil (Si-Vi content is 3 mmol / g), and 5 g of polysorbate 80 to a high-speed disperser. After heating to 20 °C, under high-speed dispersion (rotation speed 8000 rpm), slowly add 100 g of molten dodecane C 12 H 26 Maintain stirring for 3 h to form a stable oil-in-oil emulsion; add 0.005 g of platinum-carbon catalyst to the emulsion, stir evenly, then pour the emulsion into a mold, and cure it at 80 °C for 0.5 h to obtain a flexible phase change energy storage material.

[0053] Example 4

[0054] A preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system provided in this example includes the following steps:

[0055] Add 150 g of hydrogen-containing silicone oil (Si-H content is 1 mmol / g), 50 g of vinyl silicone oil (Si-Vi content is 2 mmol / g), and 3 g of sorbitan monooleate to a high-speed disperser. After heating to 80 °C, under high-speed dispersion (rotation speed 5000 rpm), slowly add 100 g of molten stearic acid C 18 H 36 COOH, maintain stirring for 2 h to form a stable oil-in-oil emulsion; add 0.0075 g of hexamethyldisilazane platinite to the emulsion, stir evenly, then pour the emulsion into a mold, and cure it at 60 °C for 2 h to obtain a flexible phase change energy storage material.

[0056] Example 5

[0057] A preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system provided in this example includes the following steps:

[0058] Add 50 g of hydrogen-containing silicone oil (Si-H content is 2 mmol / g), 50 g of vinyl silicone oil (Si-Vi content is 2 mmol / g), and 3 g of sorbitan trioleate to a high-speed disperser. After heating to 70 °C, under high-speed dispersion (rotation speed 8000 rpm), slowly add 100 g of molten stearyl alcohol C18 H 38 OH, keep stirring for 1.5 h to form a stable oil-in-oil emulsion; add 0.005 g of chloroplatinic acid to the emulsion, stir evenly and then pour the emulsion into a mold, and cure at 40 °C for 24 h to obtain a flexible phase change energy storage material.

[0059] Example 6

[0060] A preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system provided in this example includes the following steps:

[0061] Add 100 g of hydrogen-containing silicone oil (Si-H content is 0.8 mmol / g), 150 g of vinyl silicone oil (Si-Vi content is 0.5 mmol / g), and 3 g of sorbitan monooleate to a high-speed disperser. After heating to 60 °C, under high-speed dispersion (rotation speed 6000 rpm), slowly add 100 g of molten docosane C 22 H 46 and keep stirring for 2 h to form a stable oil-in-oil emulsion; add 0.01 g of hexamethyldisilazane platin ate to the emulsion, stir evenly and then pour the emulsion into a mold, and cure at 100 °C for 0.5 h to obtain a flexible phase change energy storage material.

[0062] Test Example

[0063] Perform performance tests on the flexible phase change energy storage materials obtained in Examples 1-6. The test results are shown in Table 1, and the test methods are as follows:

[0064] 1. DSC test: Use a DSC 8500 differential scanning calorimeter from Perkin–Elmer, USA. Calibrate the test temperature and heat enthalpy with a high-purity standard sample of indium. Accurately weigh about 5 mg of the sample, the atmosphere is N2 (flow rate is 20 mL / min), the heating rate is 10 °C / min, and the scanning range is from 10 to 70 °C.

[0065] 2. Mechanical property test: Use a universal mechanical testing machine from Istron, USA. The tensile rate is 30 mm / min, equipped with a 200 N load cell, and the sample size is 30 mm × 10 mm × 2 mm.

[0066] Table 1 Product Performance Test

[0067] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Phase transition point (temperature) 31.2℃ 40.3℃ -8.1℃ 72.4℃ 61.6℃ 46.7℃ Phase change enthalpy 113.3 J / g 119.8 J / g 40.7 J / g 80.3 J / g 103.7 J / g 72.6 J / g Elongation at break 294％ 213％ 398％ 317％ 279％ 367％ Breaking stress 2.12 MPa 1.86 MPa 2.45 MPa 2.24 MPa 2.01 MPa 2.51 MPa

[0068] Combined with the above data, it can be seen that the phase change energy storage material described in the present invention has excellent flexibility, thermal stability and energy storage density; among them, the comprehensive index of Example 1 is relatively excellent.

[0069] The above are only the preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made by those skilled in the art within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A flexible phase change energy storage material constructed based on an oil-in-oil emulsion system, characterized in that: It includes a continuous phase, a dispersed phase and an auxiliary agent; the continuous phase includes hydrogen-containing silicone oil and vinyl silicone oil; the dispersed phase is a phase change material; the auxiliary agent includes an emulsifier and a catalyst.

2. The flexible phase change energy storage material constructed based on the oil-in-oil emulsion system according to claim 1, wherein: The phase change material includes at least one of paraffin alkane C n H 2n+2 , higher fatty acid C n H 2n COOH, higher fatty alcohol C n H 2n OH, polyethylene glycol HO(CH2CH2O) n H, where n = 12 to 32.

3. The flexible phase change energy storage material constructed based on the oil-in-oil emulsion system according to claim 1, wherein: The hydrogen-containing silicone oil has Si-H functional groups, and the Si-H content is 0.5 mmol / g - 5 mmol / g.

4. A flexible phase change energy storage material constructed based on an oil-in-oil emulsion system, characterized in that: The vinyl silicone oil has Si-Vi functional groups, and the Si-Vi content is 0.2 mmol / g - 3 mmol / g.

5. The flexible phase change energy storage material constructed based on an oil-in-oil emulsion system according to claim 1, characterized in that: The molar ratio of the Si-H functional groups in the hydrogen-containing silicone oil to the Si-Vi functional groups in the vinyl silicone oil is 1 - 1.5:

1.

6. The flexible phase change energy storage material constructed based on the oil-in-oil emulsion system according to claim 1, wherein: The emulsifier is at least one of sorbitan monooleate, sorbitan trioleate, and polysorbate 80; the dosage of the emulsifier is 2% - 5% of the mass of the phase change material.

7. A flexible phase change energy storage material constructed based on an oil-in-oil emulsion system according to claim 1, characterized in that: The catalyst is a platinum catalyst, and the platinum catalyst includes at least one of hexamethyldisilazane platinates, chloroplatinic acid, and platinum-carbon catalyst; the dosage of the platinum catalyst is 0.001% - 0.01% of the sum of the masses of the hydrogen-containing silicone oil and the vinyl silicone oil.

8. The flexible phase change energy storage material constructed based on the oil-in-oil emulsion system according to claim 1, wherein: The ratio of the mass of the phase change material to the total mass of the hydrogen-containing silicone oil and the vinyl silicone oil is 1:0.7 - 5.

9. A preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system according to any one of claims 1-8, characterized in that: It includes the following steps: Add the hydrogen-containing silicone oil, vinyl silicone oil, and emulsifier into a high-speed disperser, with a stirring speed of 2000 - 8000 rpm. After heating to 20 - 80 °C, slowly add the phase change material in a molten state under high-speed dispersion, and keep stirring for 0.5 - 3 h to form a stable oil-in-oil emulsion; add the catalyst into the oil-in-oil emulsion, stir evenly, then pour the emulsion into a mold, and cure at 20 - 100 °C for 0.5 - 24 h to obtain a flexible phase change energy storage material.

10. The preparation method of a flexible phase change energy storage material based on an oil-in-oil emulsion system according to claim 9, characterized in that: The flexible phase change energy storage material is a pod-shaped flexible phase change material.

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