Preparation method of intrinsic super-tough photo-thermal phase change energy storage material
By introducing a dynamic cross-linking system of metal ions and carboxylic acid groups into the photothermal phase change material, the interface incompatibility problem between the photothermal functional molecules and the matrix is solved, the photothermal efficiency and mechanical toughness are improved, and it is suitable for thermal management of wearable devices.
Patent Information
- Application Number
- CN202510918321.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-03
- Publication Date
- 2025-09-19
AI Technical Summary
Existing photothermal phase change materials have problems such as interface incompatibility, high modulus, poor mechanical toughness, and low photothermal efficiency, which limit their application in smart fabrics and wearable devices.
By introducing metal ions as photothermal functional molecules and constructing chemical crosslinking, utilizing the dynamic crosslinking system of carboxylic acid groups and metal ions, optimizing the molecular structure design and component ratio, the photothermal efficiency and mechanical toughness are improved, while the modulus is reduced.
Significantly improve the photothermal conversion capacity, enhance the flexibility and tensile strength of the material, meet the flexibility and comfort requirements of wearable devices, and achieve high photothermal efficiency and high mechanical toughness.
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Figure CN120665267A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of polymer material preparation, and in particular to a method for preparing an intrinsic ultra-tough photothermal phase change energy storage material. Background Art
[0002] Photothermal phase change energy storage materials can absorb light energy and store it in extreme environments, and then convert it into heat energy and release it to maintain constant temperature.
[0003] However, traditional composite photothermal phase change materials have problems such as interface incompatibility, high modulus, poor mechanical toughness, and low photothermal efficiency. The preparation method of photothermal phase change materials commonly used in current research is to dope photothermal functional materials (such as graphene) into phase change energy storage materials, but there are problems such as interface incompatibility and modulus mismatch between the photothermal functional molecules and the phase change matrix, resulting in poor mechanical toughness and low photothermal efficiency. The interface incompatibility problem between the photothermal functional molecules and the phase change matrix can then be improved through π-π interaction, but its flexibility and toughness are still poor, limiting its application in the field of smart fabrics. In addition, intrinsic photothermal cross-linked phase change energy storage materials can be prepared using p-benzoquinone dioxime as a photothermal functional molecule. The cross-linked structure gives the material excellent mechanical properties, but its modulus is high and the cross-linked structure is not easy to process. In the existing technology, the photothermal performance is improved by adding carbon materials or metal nanoparticles, but it will damage the mechanical properties of the material; and although linear polyurethane phase change materials have a certain energy storage capacity, their modulus is high and their toughness is insufficient, and they cannot be directly used in fabrics. Therefore, developing phase-change energy storage materials with both high toughness and high photothermal efficiency has become a technical challenge that needs to be solved urgently. In response to the shortcomings of the existing technology, the present invention provides a method for preparing an intrinsically super-tough photothermal phase-change energy storage material to solve the above problems. Summary of the Invention
[0004] In response to the shortcomings of the existing technology, the present invention provides a method for preparing an intrinsically super-tough photothermal phase change energy storage material, which has three significant advantages: first, it significantly improves the photothermal efficiency. By introducing metal ions as photothermal functional molecules and constructing chemical crosslinking, it effectively solves the interface incompatibility problem and greatly enhances the photothermal conversion capacity; second, it achieves high mechanical toughness. By utilizing the dynamic crosslinking system of carboxylic acid groups and metal ions, the mechanical properties of the material are enhanced at the molecular level, exhibiting excellent flexibility and tensile strength; third, it reduces the modulus to adapt to wearable applications. By optimizing the molecular structure design and component ratio, while maintaining high photothermal efficiency and mechanical toughness, the material modulus is effectively reduced, so that it meets the stringent requirements of wearable devices for flexibility and comfort.
[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A method for preparing an intrinsic ultra-tough photothermal phase change energy storage material, comprising:
[0006] Step 1: polyethylene glycol (PEG) after dehydration and dealkali is reacted with diphenylmethane diisocyanate (MDI) in solvent DMF and in the presence of catalyst DBTDL at 80°C for 2 hours to generate a terminal isocyanate prepolymer; Step 1 forms the main chain skeleton of the polyurethane to avoid side reactions caused by water / alkali.
[0007] Step 2: Add dehydrated 1,5-naphthalenediol (ND) to the product of step 1 and react at 80°C for 2 hours; in step 2, ND acts as a photothermal functional molecule chain extension to provide intrinsic photothermal conversion capability.
[0008] Step 3: Add dehydrated dimethylolpropionic acid (DMPA) to the product of step 2 and react at 80° C. for 12 hours; step 3 introduces carboxyl groups (—COOH) to provide active sites for dynamic crosslinking.
[0009] Step 4: Remove DMF from the product of step 3 under step-by-step vacuum conditions at 110° C. to obtain a carboxyl-containing linear polyurethane prepolymer (PTPCM); Step 4 removes the solvent and solidifies the prepolymer structure.
[0010] Step 5: Dissolve PTPCM in DMF, add anhydrous ferric chloride (FeCl3), and react at 80°C for 12 hours; Step 5Fe 3+ Forms a dynamic ionic cross-linked network with carboxyl groups.
[0011] Step 6: Remove DMF from the product of step 5 under step-by-step pressure and vacuum conditions at 110°C to obtain an intrinsic ultra-tough photothermal phase change energy storage material (PTPCM-Fe 3+ ). Step 6 obtains a final product with both high toughness and high photothermal efficiency.
[0012] Preferably, the molecular weight of the polyethylene glycol in step 1 is 6000, 8000, 10000 or 20000.
[0013] Preferably, the dehydration and dealkali treatment of polyethylene glycol in step 1 comprises:
[0014] PEG was melted at 80°C, 4 drops of HCl were added to neutralize the basic impurities, and the mixture was vacuum-dehydrated at 110°C.
[0015] Preferably, the pretreatment of 1,5-naphthalene diol in step 2 comprises:
[0016] After dehydration in an oven at 110°C, the solution was dissolved by ultrasonication using 10 mL DMF.
[0017] Preferably, the pretreatment of the dimethylolpropionic acid in step 3 is carried out by dehydration in an oven at 110°C.
[0018] Preferably, the step-by-step pressure-boosting vacuum program steps of step 4 and step 6 include:
[0019] Maintain pressure at 0.2MPa for 10min, 0.4MPa for 10min, 0.6MPa for 10min, and 0.8MPa for 12h.
[0020] Preferably, the amount of anhydrous ferric chloride added in step 5 satisfies:
[0021] Fe 3+ The molar ratio of hydroxyl group to carboxyl group is (0.8–1.2):1.
[0022] Preferably, the Fe 3+ The molar ratio of hydroxyl group to carboxyl group is 1:1.
[0023] Preferably, the amount of the catalyst DBTDL used in step 1 is 4 drops / 30 mL of DMF, and the molar ratio of PEG to MDI in step 1 is 1:3.
[0024] Preferably, the molar ratio of the amount of ND added to PEG in step 2 is 1:1, and the molar ratio of the amount of DMPA added to PEG in step 3 is 1:1.
[0025] The present invention discloses a method for preparing an intrinsically ultra-tough photothermal phase change energy storage material, which has the following beneficial effects:
[0026] 1. Traditional composite photothermal phase change materials suffer from low photothermal efficiency. However, the present invention chemically introduces metal ions as photothermal functional molecules into the phase change material, solving the interfacial incompatibility problem between the photothermal functional molecules and the matrix, and significantly improving the photothermal conversion efficiency. For example, the intrinsic ultra-tough photothermal phase change energy storage material prepared by introducing iron ions and dynamic cross-linking of carboxyl groups in the preparation method, under simulated sunlight, increased its temperature from 25°C to 80°C within 30 minutes, and its photothermal conversion capacity was significantly enhanced.
[0027] 2. In the prior art, photothermal phase change materials have the problem of poor mechanical toughness. After improving the interface incompatibility through π-π interaction, the flexibility and toughness are still poor. The present invention introduces carboxylic acid groups into the polymer structure, uses carboxyl groups and metal ions for cross-linking, constructs a dynamic cross-linking system, and further improves the mechanical properties of the material. For example, the carboxyl-containing linear polyurethane prepolymer (PTPCM-10K) obtained in the preparation method has a maximum breaking strength of 22MPa and a maximum elongation at break of 1600%; the intrinsic super-tough photothermal phase change energy storage material obtained in the preparation method has a toughness greater than 200MJ / m 3 , indicating that the material has excellent mechanical properties.
[0028] 3. Traditional photothermal phase change materials have a high modulus and are not suitable for wearable thermal management. However, the present invention optimizes the molecular structure design and the construction of a dynamic cross-linking system, thereby improving the photothermal conversion efficiency and mechanical toughness while reducing the modulus of the material, making it suitable for wearable thermal management. For example, by controlling the molecular weight of polyethylene glycol (preferably 10,000) and rationally adjusting the molar ratio of each component, the problem of excessive material modulus caused by excessive introduction of photothermal functional molecules (such as 1,5-naphthalene diol) is avoided, thereby meeting the requirements of wearable devices for material flexibility and comfort. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0030] Figure 1 This is the infrared spectrum of the material obtained in Example 2 of the present invention;
[0031] Figure 2 This is a tensile stress-strain curve of the material obtained in Example 2 of the present invention;
[0032] Figure 3 The light-to-heat conversion curves of the materials obtained in Examples 2 and 3 of the present invention are shown;
[0033] Figure 4 This is a comparison chart of the materials obtained in Examples 2 and 3 of the present invention. DETAILED DESCRIPTION
[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0035] The embodiments of the present application provide a method for preparing an intrinsic ultra-tough photothermal phase change energy storage material. By designing the molecular structure and constructing a dynamic cross-linking system, the problems of poor mechanical toughness and low photothermal efficiency of existing materials are solved, and their application in smart fabrics is expanded. The research basis of the present invention is to prepare a linear intrinsic photothermal phase change energy storage material with excellent mechanical properties by polycondensation of polyethylene glycol, 1-5-naphthalene diol, and diphenylmethane diisocyanate. However, there are currently three problems: 1. Low photothermal conversion efficiency. 2. Mechanical toughness needs to be further improved. 3. High modulus, which is not suitable for wearable thermal management. The photothermal conversion ability comes from naphthalene diol, and if too much of this molecule is introduced, the modulus of the material will be too high, making it difficult to wear. Therefore, it is a great challenge to improve the toughness of the material while improving the conversion efficiency. Therefore, by introducing carboxylic acid groups into the polymer structure to increase the intermolecular force of the polymer, and by chemically introducing metal ions as photothermal functional molecules into the phase change material, the problem of interface incompatibility between the photothermal functional molecules and the matrix is solved. Carboxyl groups and metal ions can be used for cross-linking to further improve the mechanical properties of the material. Photothermal phase change energy storage materials can be prepared without affecting the mechanical properties of the material. The introduction of metal ions can not only improve the photothermal conversion efficiency but also dynamically cross-link with carboxyl groups to enhance the mechanical properties of the material and fiber.
[0036] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.
[0037] Example 1: The present invention discloses a method for preparing an intrinsic ultra-tough photothermal phase change energy storage material. Figure 1-4 As shown, including:
[0038] Step 1: polyethylene glycol (PEG) after dehydration and dealkali is reacted with diphenylmethane diisocyanate (MDI) in solvent DMF and in the presence of catalyst DBTDL at 80°C for 2 hours to generate a terminal isocyanate prepolymer; Step 1 forms the main chain skeleton of the polyurethane to avoid side reactions caused by water / alkali.
[0039] Step 2: Add dehydrated 1,5-naphthalenediol (ND) to the product of step 1 and react at 80°C for 2 hours; in step 2, ND serves as a photothermal functional molecule chain extension to provide intrinsic photothermal conversion capability.
[0040] Step 3: Add dehydrated dimethylolpropionic acid (DMPA) to the product of step 2 and react at 80° C. for 12 hours; step 3 introduces carboxyl groups (—COOH) to provide active sites for dynamic cross-linking.
[0041] Step 4: Remove DMF from the product of step 3 under step-by-step vacuum conditions at 110° C. to obtain a carboxyl-containing linear polyurethane prepolymer (PTPCM); Step 4 removes the solvent and solidifies the prepolymer structure.
[0042] Step 5: Dissolve PTPCM in DMF, add anhydrous ferric chloride (FeCl3), and react at 80°C for 12 hours; Step 5Fe 3+ Forms a dynamic ionic cross-linked network with carboxyl groups.
[0043] Step 6: Remove DMF from the product of step 5 under step-by-step pressure and vacuum conditions at 110°C to obtain an intrinsic ultra-tough photothermal phase change energy storage material (PTPCM-Fe 3+ ). Step 6 obtains a final product with both high toughness and high photothermal efficiency.
[0044] The molecular weight of the polyethylene glycol in step 1 is 6000, 8000, 10000 or 20000. The molecular weight affects the phase change enthalpy and segment flexibility, and preferably 10000 has the best mechanical properties.
[0045] The dehydration and dealkali treatment of polyethylene glycol in step 1 includes:
[0046] PEG was melted at 80°C, 4 drops of HCl were added to neutralize alkaline impurities, and then vacuum-dehydrated at 110°C. This treatment process prevented residual water / alkali from consuming isocyanate groups, ensuring reaction efficiency.
[0047] The pretreatment of 1,5-naphthalene diol in step 2 includes:
[0048] After dehydration in a 110°C oven, 10 mL of DMF was used for ultrasonic dissolution. The above pretreatment process eliminated the interference of moisture and ensured that ND participated in the chain extension reaction uniformly.
[0049] The pretreatment of the bis(hydroxymethyl)propionic acid in step 3 is performed by dehydration in an oven at 110° C. The above pretreatment process prevents moisture from causing hydrolysis of the prepolymer or failure of crosslinking.
[0050] The steps of the step-by-step vacuum boosting procedure in step 4 and step 6 include:
[0051] Maintain pressure at 0.2 MPa for 10 minutes, 0.4 MPa for 10 minutes, 0.6 MPa for 10 minutes, and 0.8 MPa for 12 hours. Gradual pressure increase prevents rapid solvent evaporation from causing material porosity defects.
[0052] The amount of anhydrous ferric chloride added in step 5 satisfies:
[0053] Fe 3+ The molar ratio of Fe to carboxyl is (0.8–1.2):1. 3+When the molar ratio to carboxyl group is less than 0.8, the crosslinking is insufficient; when it is greater than 1.2, the rigidity is too strong; and when it is 1:1, the toughness / photothermal synergy is optimal.
[0054] Fe 3+ The molar ratio of the carbonyl group to the carboxyl group is 1:1. This ratio maximizes the dynamic crosslinking density of the material, increases the elongation at break to 1300%, and achieves a photothermal conversion efficiency of 80°C / 30min.
[0055] The amount of catalyst DBTDL used in step 1 is 4 drops / 30 mL DMF, and the molar ratio of PEG to MDI in step 1 is 1:3, thereby ensuring an excess of MDI to generate a terminal-NCO prepolymer for subsequent ND / DMPA chain extension.
[0056] The molar ratio of the amount of ND added to PEG in step 2 was 1:1, and the molar ratio of the amount of DMPA added to PEG in step 3 was 1:1.
[0057] In order to better understand the technical solution of the present invention, the reaction process is described as follows:
[0058] A method for preparing an intrinsically ultra-tough photothermal phase change energy storage material comprises the following steps:
[0059] Step 1: Add polyethylene glycol and diphenylmethane diisocyanate after dehydration and dealkali into a reaction flask, use DMF as solvent and DBTDL as catalyst, and stir the reaction at 80°C for 2 hours;
[0060] Step 2: Add 1,5-naphthalene diol to the product obtained in step 1, and stir the mixture at 80°C for 2 hours;
[0061] Step 3: Add bis(hydroxymethyl)propionic acid to the product obtained in step 2 to introduce a carboxyl group, and stir the reaction at 80°C for 12 hours;
[0062] Step 4: Take out the product obtained in step 3 and place it in a polytetrafluoroethylene culture dish, and place it in a vacuum oven at 110° C. to remove the solvent to obtain a carboxyl-containing linear polyurethane prepolymer.
[0063] Step 5: Take out the prepolymer obtained in step 4, add DMF to dissolve it, add anhydrous ferric chloride to introduce metal ions, and stir the reaction at 80°C for 12 hours;
[0064] Step 6: Take out the product of step 1 and place it in a polytetrafluoroethylene culture dish. Remove the solvent in a vacuum oven at 110°C to obtain an intrinsic ultra-tough photothermal phase change energy storage material.
[0065] Example 2: Carboxyl-containing linear polyurethane prepolymer (PTPCM for short);
[0066] A method for preparing a carboxyl-containing linear polyurethane prepolymer (PTPCM for short).
[0067] 12 g, 18 g, 20 g, and 40 g of polyethylene glycol (0.002 mol) with molecular weights of 6000, 8000, 10000, and 20000 were weighed in proportion and added to the reaction flask to melt, 4 drops of HCl were added to remove the base, the temperature was raised to 110 ° C and vacuumed to remove water, and then 1.5075 g of diphenylmethane diisocyanate (0.006 mol) was added, 4 drops of DBTDL as a catalyst, and 30 mL of DMF as a solvent. The reaction was stirred at 80 ° C for 2 hours. Weigh 0.32034g 1,5-naphthalenediol (0.002mol) and add it to a reagent bottle, add 10mL DMF to dissolve it, add 1,5-naphthalenediol solution to the reaction flask, stir and react at 80°C for 2 hours; weigh 0.26826g bis(hydroxymethyl)propionic acid (0.002mol), introduce carboxyl groups, and stir and react at 80°C for 12 hours; take out the resulting product and place it in a polytetrafluoroethylene culture dish, remove the solvent in a vacuum oven at 110°C, vacuum the pressure to 0.2Mpa, and maintain the pressure for 10 minutes; the pressure is 0.4Mpa, and the pressure is maintained for 10 minutes; the pressure is 0.6Mpa, and the pressure is maintained for 10 minutes; the pressure is 0.8Mpa, and the pressure is maintained for 12 hours to obtain a carboxyl-containing linear polyurethane prepolymer for standby use.
[0068] The infrared spectrum and tensile stress-strain curve of the product are shown in Figure 1 and Figure 2 , Figure 1 This is the infrared spectrum of the material prepared in Example 2, showing the presence of an ether bond of carbamate near 1220 cm-1 and a hydroxyl peak of carboxyl near 2800 cm-1, confirming the formation of a polyurethane structure; Figure 2 The tensile stress-strain curve of the material obtained in Example 2 shows a breaking strength of 22 MPa and a breaking elongation of 1600%. Figure 1 It can be seen that there is an ether bond of carbamate near 1220cm-1 and a hydroxyl peak of carboxyl near 2800cm-1, which proves that the polyurethane structure is formed. Figure 2 The results show that PTPCM-10K has the highest breaking strength of 22 MPa and the highest breaking elongation of 1600%. It can be seen that the carboxyl-containing linear polyurethane prepolymer with a PEG molecular weight of 10,000 has the best mechanical properties and will be used in subsequent experiments.
[0069] Example 3: Intrinsic ultra-tough photothermal phase change energy storage material (abbreviated as PTPCM-Fe3+);
[0070] 10 g of a carboxyl-containing linear polyurethane prepolymer (PTPCM-10K) with the best mechanical properties and photothermal conversion properties was weighed and added to a reaction flask, 30 mL of DMF was added and stirred to dissolve at 80°C, 0.1468 g of anhydrous ferric chloride was introduced according to the 1:1 ratio of the carboxyl group of dihydroxymethylpropionic acid (0.002 mol) and anhydrous ferric chloride (0.002 mol), and the reaction was stirred at 80°C for 12 hours; the resulting product was taken out and placed in a polytetrafluoroethylene culture dish, and the solvent was removed in a vacuum oven at 110°C, the vacuum pressure was 0.2 MPa, and the pressure was maintained for 10 minutes; the pressure was 0.4 MPa, and the pressure was maintained for 10 minutes; the pressure was 0.6 MPa, and the pressure was maintained for 10 minutes; the pressure was 0.8 MPa, and the pressure was maintained for 12 hours to obtain an intrinsic ultra-tough photothermal phase change energy storage material.
[0071] The photothermal conversion curve of this product and the comparison chart of material literature are as follows Figure 3 and Figure 4 . Figure 3 3 is the light-to-heat conversion curve of the materials obtained in Examples 2 and 3, showing that under simulated sunlight, the temperature rises from 25°C to 80°C within 30 minutes. Figure 4 It is a comparison chart of the material documents obtained in Examples 2 and 3. Compared with the enthalpy and toughness of most existing documents, the enthalpy and toughness of the prepared materials are significantly higher than those of other materials. It can be seen from the figure that the carboxyl-containing linear polyurethane prepolymer without iron ions has a large temperature change (25°C-55°C), but the intrinsic super-tough photothermal phase change energy storage material prepared by dynamic cross-linking of iron ions and carboxyl groups has a more obvious temperature change (25°C-80°C) within the same time, and the photothermal conversion ability is significantly enhanced. At the same time, the introduction of iron ions and carboxyl groups also significantly improves the mechanical properties of the photothermal phase change energy storage material, with toughness greater than 200MJ / m3. It shows that the material has good photothermal conversion ability and excellent mechanical properties.
[0072] In summary, the present invention discloses a method for preparing an ultra-tough photothermal phase change energy storage material. Through molecular structure design and dynamic cross-linking system construction, polyethylene glycol, 1-5-naphthalene diol, and diphenylmethane diisocyanate are first used to prepare a linear intrinsic photothermal phase change energy storage material with excellent mechanical properties by polycondensation. Then, carboxylic acid groups are introduced into the polymer structure to increase the intermolecular force of the polymer, and metal ions are introduced into the phase change material as photothermal functional molecules by chemical means to solve the problem of interface incompatibility between the photothermal functional molecules and the matrix. In addition, carboxyl groups and metal ions can be used for cross-linking to further improve the mechanical properties of the material, and photothermal phase change energy storage materials can be prepared without affecting the mechanical properties of the material. It solves the problems of poor mechanical toughness, low photothermal efficiency, and high modulus of existing photothermal phase change materials, and expands their thermal management applications in extreme environments.
[0073] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.
[0074] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.
Claims
1. A method for preparing an intrinsically ultra-tough photothermal phase change energy storage material, characterized in that: include: Step 1: reacting polyethylene glycol (PEG) after dehydration and dealkali with diphenylmethane diisocyanate (MDI) in DMF solvent and in the presence of DBTDL catalyst at 80° C. for 2 hours to form an isocyanate-terminated prepolymer; Step 2: Add dehydrated 1,5-naphthalene diol (ND) to the product of step 1 and react at 80°C for 2 hours; Step 3: Add dehydrated dimethylolpropionic acid (DMPA) to the product of step 2 and react at 80° C. for 12 hours; Step 4: removing DMF from the product of step 3 under stepwise vacuum conditions at 110° C. to obtain a carboxyl-containing linear polyurethane prepolymer (PTPCM); Step 5: Dissolve PTPCM in DMF, add anhydrous ferric chloride (FeCl3), and react at 80°C for 12 hours; Step 6: Remove DMF from the product of step 5 under step-by-step pressure and vacuum conditions at 110°C to obtain an intrinsic ultra-tough photothermal phase change energy storage material (PTPCM-Fe 3+ ).
2. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 1, characterized in that: The molecular weight of the polyethylene glycol in step 1 is 6000, 8000, 10000 or 20000.
3. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 1, characterized in that: The dehydration and dealkali treatment of polyethylene glycol in step 1 comprises: PEG was melted at 80°C, 4 drops of HCl were added to neutralize the basic impurities, and the mixture was vacuum-dehydrated at 110°C.
4. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 1, characterized in that: The pretreatment of 1,5-naphthalene diol in step 2 comprises: After dehydration in an oven at 110°C, the solution was dissolved by ultrasonication using 10 mL DMF.
5. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 1, characterized in that: The pretreatment of the dimethylolpropionic acid in step 3 is carried out by dehydration in an oven at 110°C.
6. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 1, characterized in that: The step-by-step pressure boosting vacuum procedure steps of step 4 and step 6 include: Maintain pressure at 0.2MPa for 10min, 0.4MPa for 10min, 0.6MPa for 10min, and 0.8MPa for 12h.
7. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 1, characterized in that: The amount of anhydrous ferric chloride added in step 5 satisfies: Fe 34 The molar ratio of hydroxyl group to carboxyl group is (0.8–1.2):
1.
8. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 7, characterized in that: The Fe 3+ The molar ratio of hydroxyl group to carboxyl group is 1:
1.
9. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 1, characterized in that: The amount of the catalyst DBTDL used in step 1 is 4 drops / 30 mL of DMF, and the molar ratio of PEG to MDI in step 1 is 1:
3.
10. The method for preparing an intrinsic ultra-tough photothermal phase change energy storage material according to claim 1, characterized in that: The molar ratio of the amount of ND added in step 2 to PEG is 1:1, and the molar ratio of the amount of DMPA added in step 3 to PEG is 1:1.