PCM-based energy storage building material and preparation method thereof

Abstract

The invention relates to a PCM-based energy storage building material and a preparation method thereof, and belongs to the technical field of building materials. The energy storage building material is prepared from the following components in parts by weight: 55 to 70 parts of ordinary Portland cement, 10 to 20 parts of aluminate cement, 10 to 15 parts of gypsum, 140 to 170 parts of fine aggregate, 15 to 25 parts of mineral powder, 18 to 26 parts of paraffin microcapsules, 5 to 7 parts of redispersible rubber powder, 0.8 to 1 part of water reducing agent and 75 to 83 parts of water, the paraffin microcapsule is coated through in-situ crosslinking, the encapsulation structure is more stable, calcium thioacetate on the surface of the paraffin microcapsule promotes formation of hydrated gel in the building material, the strength of a fully hydrated gel layer close to the surface layer of the paraffin microcapsule is high, a structural supporting effect is formed on the paraffin microcapsule, and the stability of the capsule structure is further maintained; in the using process, leakage is not prone to occurring, and the stable energy storage effect is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of building materials, and in particular, relates to a PCM-based energy storage building material and a preparation method thereof. Background Art

[0002] With the continuous growth of energy demand and the increasing impact of energy consumption on the environment, energy conservation and emission reduction have become important issues that need to be urgently addressed in today's society. In the field of construction, traditional building materials have high thermal conductivity and low thermal inertia, which leads to large fluctuations in indoor temperature and low energy efficiency. Phase change material (PCM), as a new type of energy-saving material, can use the latent heat released or absorbed during the temperature change process to adjust the internal temperature of the building, thereby reducing dependence on traditional heating and air-conditioning systems, reducing energy consumption, and improving the energy efficiency of buildings.

[0003] In early research, direct mixing was often used to combine PCM with a matrix. This means that PCM is directly combined with building materials such as cement, gypsum, and concrete without encapsulation. This method is simple and direct and has a high PCM loading capacity. However, during the energy storage process, PCM cycles between liquid and solid phases, and PCM is easily lost, resulting in deterioration of heat storage performance. The emulsified microencapsulation method is used to encapsulate PCM in a polymer shell, which can effectively alleviate the leakage problem of PCM. However, in actual application, it is difficult for the polymer to form a stable and uniform cross-linked layer on the PCM surface. During the mixing and curing of cement composite building materials, the shell is easily damaged. During the phase change process, it is accompanied by shrinkage and expansion, which is prone to leakage, seriously affecting the energy storage effect. Summary of the invention

[0004] In order to solve the technical problems mentioned in the background technology, the purpose of the present invention is to provide a PCM-based energy storage building material and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A PCM-based energy storage building material comprises the following raw materials in parts by weight: 55-70 parts of ordinary Portland cement, 10-20 parts of aluminate cement, 10-15 parts of gypsum, 140-170 parts of fine aggregate, 15-25 parts of mineral powder, 18-26 parts of paraffin microcapsules, 5-7 parts of redispersible rubber powder, 0.8-1 parts of water reducer and 75-83 parts of water.

[0006] Paraffin microcapsules were prepared by the following method: Step A1: premix pentamethylene glycol, triethylamine and anhydrous tetrahydrofuran, dry nitrogen protection, control the water bath temperature at 10-20°C, slowly add methylvinyldichlorosilane and stir to react for 1.5-2h, then add propylene diamine, raise the temperature to 45-55°C and stir to react for 30-40min, after the reaction is completed, remove tetrahydrofuran by rotary evaporation to obtain an intermediate; Furthermore, the feed ratio of methylvinyldichlorosilane, pentamethylene glycol, propylene diamine, triethylamine and anhydrous tetrahydrofuran is 0.1 mol: 80-90 mmol: 15-30 mmol: 6-10 mL: 45-55 mL, methylvinyldichlorosilane and pentamethylene glycol are substituted to form an alkyl chain block oligomer, and then the amino group is introduced by active propylene diamine to terminate the reaction.

[0007] Step A2: Mix the intermediate, thioglycolic acid, photoinitiator and acetone, protect with nitrogen, and apply 150-200W / m 2 UV irradiation, stirring and reacting for 5-7 hours, after the reaction is completed, acetone is evaporated under reduced pressure to obtain a modifier; Furthermore, the feed ratio of the intermediate, thioglycolic acid, photoinitiator and acetone is 10g:35-50mmol:10-15mg:40-50mL, and under ultraviolet initiation, thioglycolic acid and the double bond of the intermediate molecular side chain are click-added.

[0008] Step A3: preheat the paraffin wax and the modifier to dissolve, add deionized water to shear and disperse, control the water bath temperature to 50-60°C, apply stirring at 180-240rpm, slowly add isophorone diisocyanate to react for 1-1.5h, then add calcium oxide and continue stirring for 2-3h, cool after the reaction is completed, filter and remove the water phase, wash the substrate with water and then vacuum dry to obtain paraffin microcapsules; Furthermore, the feed ratio of paraffin, modifier, isophorone diisocyanate, calcium oxide and deionized water is 50g:4.5-6g:2.2-2.8g:12-16g:130-160mL, the modifier is attached to the surface of the paraffin emulsion droplets, its terminal amino group is cross-linked with isophorone diisocyanate to coat the paraffin, and the carboxylic acid structure of its molecular side chain reacts with calcium oxide to form calcium carboxylate for surface modification.

[0009] Preferably, the fine aggregate is machine-made sand with a fineness modulus of 1.7-2.5, which has a good flow-filling effect after compounding.

[0010] Preferably, the mineral powder is a mixture of limestone powder and fly ash, has good reactivity, and can fully participate in hydration on the surface of the paraffin microcapsule in the early stage to form a dense gel layer.

[0011] Preferably, the water reducing agent is selected from polycarboxylic acid water reducing agent, which has a high efficiency water reducing effect, maintains the fluidity of the composite mortar, and is conducive to the dispersion of paraffin microcapsules.

[0012] A preparation method of a PCM-based energy storage building material comprises the following steps: premixing ordinary Portland cement, aluminate cement, gypsum, mineral powder, paraffin microcapsules and redispersible rubber powder, adding fine aggregate and mixing evenly, dispersing a water reducer in water and then adding the mixture and mixing evenly to obtain a PCM-based energy storage building material.

[0013] Beneficial effects of the present invention: The invention is based on a paraffin phase change energy storage material, and through a modified encapsulation treatment, the paraffin microcapsule is substituted by methylvinyldichlorosilane and pentamethylene glycol to form an alkyl chain block oligomer, and then an amino end-capping is introduced by active propylene diamine to prepare an intermediate, and then a side chain thioacetic acid structure is introduced by double bond click addition of thioglycolic acid and a side chain of the intermediate molecule to prepare a modifier, and then the paraffin is coated by cross-linking the modifier with isophorone diisocyanate, the thioacetic acid structure on the side chain of the modifier molecule is neutralized with calcium oxide, and calcium acetate is introduced to modify the surface of the coating layer; compared with the traditional external emulsion Compared with the chemical encapsulation technology, the main chain of the modifier contains a large number of alkyl chain blocks and has good affinity with paraffin. The thioacetic acid structure of the side chain has high polarity and is easy to adhere to the surface of paraffin droplets during shear dispersion. The terminal active amino group cross-links with isophorone diisocyanate to form an in-situ coating on paraffin, and the formed encapsulation structure is more stable. The calcium thioacetate on the surface of paraffin microcapsules promotes the formation of hydrated gel in building materials. The fully hydrated gel layer near the surface has high strength, which forms a structural support for the paraffin microcapsules, further maintaining the stability of the capsule structure. It is not easy to leak during use and plays a stable energy storage role. DETAILED DESCRIPTION

[0014] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] Example 1: Preparation of PCM-based energy storage building materials, as follows: (1) Preparation of paraffin microcapsules Step A1: Pre-mix pentamethylene glycol, triethylamine and anhydrous tetrahydrofuran, introduce dry nitrogen for protection, control the water bath temperature at 10°C, control the stirring rate at 30rpm, slowly add methylvinyldichlorosilane and stir to react for 2h, then add propylene diamine and mix, heat to 45°C, increase the stirring rate to 90rpm, and stir to react for 40min, wherein the feed ratio of methylvinyldichlorosilane, pentamethylene glycol, propylene diamine, triethylamine and anhydrous tetrahydrofuran is 0.1mol:90mmol:15mmol:6mL:45mL, and after the reaction, remove tetrahydrofuran by rotary evaporation to obtain an intermediate.

[0016] Step A2: Take the intermediate, thioglycolic acid, photoinitiator and acetone, mix them, pass nitrogen protection, apply 150W / m 2 The reaction was carried out under ultraviolet irradiation and stirred at 120 rpm for 7 hours, wherein the photoinitiator was photoinitiator 1173, and the feed ratio of the intermediate, thioglycolic acid, photoinitiator and acetone was 10 g:35 mmol:10 mg:40 mL. After the reaction was completed, the acetone was evaporated under reduced pressure to obtain a modifier.

[0017] Step A3: preheat paraffin and modifier to 40°C for miscibility, add deionized water and shear and disperse at 1200rpm for 5min, control the water bath temperature at 50°C, stir at 180rpm, slowly add isophorone diisocyanate to react for 1.5h, then add calcium oxide and continue stirring for 3h, wherein the feed ratio of paraffin, modifier, isophorone diisocyanate, calcium oxide and deionized water is 50g:4.5g:2.2g:12g:130mL, cool and filter to remove the aqueous phase after the reaction, wash the substrate with water and vacuum dry to obtain paraffin microcapsules.

[0018] (2) Preparation of PCM-based energy storage building materials Ingredients are prepared in parts by weight: 70 parts of ordinary Portland cement, using P.O42.5 type cement raw material; 10 parts of aluminate cement, using A600 type cement raw material; 10 parts of gypsum, industrial-grade building gypsum raw material; 170 parts of fine aggregate, compounded by machine-made sand with fineness modulus 1.7, 1.9, 2.2 and 2.5 in a weight ratio of 1:2:2:1; 25 parts of mineral powder, using industrial-grade limestone powder and fly ash in a weight ratio of 2:1; 18 parts of paraffin microcapsules, prepared in this embodiment; 7 parts of redispersible rubber powder, using VINNAPAS®5044N type raw material; 1 part of water reducer, using GK-3000 type polycarboxylate water reducer; 83 parts of water.

[0019] Blending: Add ordinary Portland cement, aluminate cement, gypsum, mineral powder, paraffin microcapsules and redispersible rubber powder into a stirrer, stir at 30 rpm for 10 min, disperse the water reducer into water, add it into the mixture and mix well to obtain PCM-based energy storage building materials.

[0020] Example 2, preparation of PCM-based energy storage building materials, as follows: (1) Preparation of paraffin microcapsules Step A1: Pre-mix pentamethylene glycol, triethylamine and anhydrous tetrahydrofuran, introduce dry nitrogen for protection, control the water bath temperature at 20°C, control the stirring rate at 50rpm, slowly add methylvinyldichlorosilane and stir to react for 1.5h, then add propylene diamine and mix, heat to 55°C, increase the stirring rate to 120rpm, and stir to react for 30min, wherein the feed ratio of methylvinyldichlorosilane, pentamethylene glycol, propylene diamine, triethylamine and anhydrous tetrahydrofuran is 0.1mol:80mmol:30mmol:10mL:55mL, and after the reaction, remove tetrahydrofuran by rotary evaporation to obtain an intermediate.

[0021] Step A2: Take the intermediate, thioglycolic acid, photoinitiator and acetone, mix them, pass nitrogen protection, apply 200W / m 2 The reaction was carried out under ultraviolet irradiation and stirred at 150 rpm for 5 hours, wherein the photoinitiator was photoinitiator 1173, and the feed ratio of the intermediate, thioglycolic acid, photoinitiator and acetone was 10 g:50 mmol:15 mg:50 mL. After the reaction was completed, the acetone was evaporated under reduced pressure to obtain a modifier.

[0022] Step A3: preheat paraffin and modifier to 40°C for miscibility, add deionized water and shear and disperse at 1200rpm for 5min, control the water bath temperature at 60°C, apply stirring at 240rpm, slowly add isophorone diisocyanate to react for 1h, then add calcium oxide and continue stirring for 2h, wherein the feed ratio of paraffin, modifier, isophorone diisocyanate, calcium oxide and deionized water is 50g:6g:2.8g:16g:160mL, cool and filter to remove the aqueous phase after the reaction, wash the substrate with water and vacuum dry to obtain paraffin microcapsules.

[0023] (2) Preparation of PCM-based energy storage building materials Ingredients are prepared in parts by weight: 55 parts of ordinary Portland cement, using P.O42.5 type cement raw material; 20 parts of aluminate cement, using A600 type cement raw material; 15 parts of gypsum, industrial-grade building gypsum raw material; 140 parts of fine aggregate, compounded by machine-made sand with fineness modulus 1.7, 1.9, 2.2 and 2.5 in a weight ratio of 1:2:2:1; 15 parts of mineral powder, using industrial-grade limestone powder and fly ash in a weight ratio of 2:1; 26 parts of paraffin microcapsules, prepared in this embodiment; 5 parts of redispersible rubber powder, using VINNAPAS®5044N type raw material; 0.8 parts of water reducer, using GK-3000 type polycarboxylic acid water reducer; 75 parts of water.

[0024] Blending: Add ordinary Portland cement, aluminate cement, gypsum, mineral powder, paraffin microcapsules and redispersible rubber powder into a stirrer, stir at 30 rpm for 10 min, disperse the water reducer into water, add it into the mixture and mix well to obtain PCM-based energy storage building materials.

[0025] Example 3, preparation of PCM-based energy storage building materials, as follows: (1) Preparation of paraffin microcapsules Step A1: Pre-mix pentamethylene glycol, triethylamine and anhydrous tetrahydrofuran, introduce dry nitrogen for protection, control the water bath temperature at 15°C, control the stirring rate at 50rpm, slowly add methylvinyldichlorosilane and stir to react for 1.7h, then add propylene diamine and mix, heat to 50°C, increase the stirring rate to 120rpm, and stir to react for 35min, wherein the feed ratio of methylvinyldichlorosilane, pentamethylene glycol, propylene diamine, triethylamine and anhydrous tetrahydrofuran is 0.1mol:85mmol:20mmol:8mL:50mL, and after the reaction, remove tetrahydrofuran by rotary evaporation to obtain an intermediate.

[0026] Step A2: Take the intermediate, thioglycolic acid, photoinitiator and acetone, mix them, pass nitrogen protection, and apply 180W / m at room temperature. 2 The reaction was carried out under ultraviolet irradiation and stirred at 150 rpm for 6 hours, wherein the photoinitiator was photoinitiator 1173, and the feed ratio of the intermediate, thioglycolic acid, photoinitiator and acetone was 10 g:45 mmol:12 mg:45 mL. After the reaction was completed, the acetone was evaporated under reduced pressure to obtain a modifier.

[0027] Step A3: preheat paraffin and modifier to 40°C for miscibility, add deionized water and shear and disperse at 1200rpm for 5min, control the water bath temperature to 55°C, stir at 240rpm, slowly add isophorone diisocyanate to react for 1.2h, then add calcium oxide and continue stirring for 2.5h, wherein the feed ratio of paraffin, modifier, isophorone diisocyanate, calcium oxide and deionized water is 50g:5.5g:2.5g:14g:150mL, cool and filter to remove the aqueous phase after the reaction, wash the substrate with water and vacuum dry to obtain paraffin microcapsules.

[0028] (2) Preparation of PCM-based energy storage building materials Ingredients are prepared in parts by weight: 65 parts of ordinary Portland cement, using P.O42.5 type cement raw material; 12 parts of aluminate cement, using A600 type cement raw material; 13 parts of gypsum, industrial-grade building gypsum raw material; 160 parts of fine aggregate, compounded by machine-made sand with fineness modulus 1.7, 1.9, 2.2 and 2.5 in a weight ratio of 1:2:2:1; 22 parts of mineral powder, using industrial-grade limestone powder and fly ash in a weight ratio of 2:1; 22 parts of paraffin microcapsules, prepared in this embodiment; 6 parts of redispersible rubber powder, using VINNAPAS®5044N type raw material; 0.8 parts of water reducer, using GK-3000 type polycarboxylic acid water reducer; 80 parts of water.

[0029] Blending: Add ordinary Portland cement, aluminate cement, gypsum, mineral powder, paraffin microcapsules and redispersible rubber powder into a stirrer, stir at 30 rpm for 10 min, disperse the water reducer into water, add it into the mixture and mix well to obtain PCM-based energy storage building materials.

[0030] Example 4: Preparation of PCM-based energy storage building materials, as follows: (1) Preparation of paraffin microcapsules Step A1: Pre-mix pentamethylene glycol, triethylamine and anhydrous tetrahydrofuran, introduce dry nitrogen for protection, control the water bath temperature at 20°C, control the stirring rate at 50rpm, slowly add methylvinyldichlorosilane and stir to react for 1.7h, then add propylene diamine and mix, heat to 45°C, increase the stirring rate to 120rpm, and stir to react for 35min, wherein the feed ratio of methylvinyldichlorosilane, pentamethylene glycol, propylene diamine, triethylamine and anhydrous tetrahydrofuran is 0.1mol:90mmol:20mmol:8mL:50mL, and after the reaction, remove tetrahydrofuran by rotary evaporation to obtain an intermediate.

[0031] Step A2: Take the intermediate, thioglycolic acid, photoinitiator and acetone, mix them, pass nitrogen protection, apply 200W / m 2The reaction was carried out under ultraviolet irradiation and stirred at 150 rpm for 6 hours, wherein the photoinitiator was photoinitiator 1173, and the feed ratio of the intermediate, thioglycolic acid, photoinitiator and acetone was 10 g:40 mmol:10 mg:45 mL. After the reaction was completed, the acetone was evaporated under reduced pressure to obtain a modifier.

[0032] Step A3: preheat paraffin and modifier to 40°C for miscibility, add deionized water and shear and disperse at 1200rpm for 5min, control the water bath temperature to 50°C, apply stirring at 240rpm, slowly add isophorone diisocyanate to react for 1.2h, then add calcium oxide and continue stirring for 3h, wherein the feed ratio of paraffin, modifier, isophorone diisocyanate, calcium oxide and deionized water is 50g:5g:2.4g:15g:150mL, cool and filter to remove the aqueous phase after the reaction, wash the substrate with water and vacuum dry to obtain paraffin microcapsules.

[0033] (2) Preparation of PCM-based energy storage building materials Ingredients are prepared in parts by weight: 60 parts of ordinary Portland cement, using P.O42.5 type cement raw material; 18 parts of aluminate cement, using A600 type cement raw material; 12 parts of gypsum, industrial-grade building gypsum raw material; 155 parts of fine aggregate, compounded by machine-made sand with fineness modulus 1.7, 1.9, 2.2 and 2.5 in a weight ratio of 1:2:2:1; 20 parts of mineral powder, using industrial-grade limestone powder and fly ash in a weight ratio of 2:1; 24 parts of paraffin microcapsules, prepared in this embodiment; 6 parts of redispersible rubber powder, using VINNAPAS®5044N type raw material; 0.9 parts of water reducer, using GK-3000 type polycarboxylic acid water reducer; 78 parts of water.

[0034] Blending: Add ordinary Portland cement, aluminate cement, gypsum, mineral powder, paraffin microcapsules and redispersible rubber powder into a stirrer, stir at 30 rpm for 10 min, disperse the water reducer into water, add it into the mixture and mix well to obtain PCM-based energy storage building materials.

[0035] In a comparative example, a polyurea-coated paraffin-type phase change material was prepared with reference to the prior art, and applied to energy storage building materials, as follows: Isophorone diisocyanate, paraffin and emulsifier OP-10 were preheated to 40°C for mixing, surfactant SDBS was dispersed in deionized water, the temperature was raised to 60°C, the mixture was added, shear emulsification was applied at 1200rpm for 5min, the stirring rate was then reduced to 150rpm, tetraethylenepentamine was slowly added and reacted for 1h, wherein the feed ratio of paraffin, isophorone diisocyanate, tetraethylenepentamine, emulsifier OP-10, surfactant SDBS and deionized water was 50g:2.5g:1.9g:0.8g:0.3g:150mL, the reaction was completed, the reaction was cooled and filtered to remove the water phase, the substrate was washed with water and then vacuum dried to obtain a polyurea-coated paraffin-type phase change material; Referring to Example 4, the paraffin microcapsules were replaced by an equal amount of polyurea-coated paraffin-type phase change material, and the rest of the implementation process was exactly the same.

[0036] Samples were taken from the paraffin microcapsules prepared in the above examples and the polyurea-coated paraffin phase change materials prepared in the comparative examples, and the melting latent heat was detected by differential scanning calorimetry, the test temperature was 0-80°C, and the temperature change rate was 5°C / min; Samples were taken from the energy storage building materials prepared in the above embodiments and comparative examples, block samples were prepared according to GB / T 17671-2021 standard, standard curing was performed for 28 days, and the compressive strength of the samples was tested; Take the block sample as above and weigh it as M0. Place the sample in petroleum ether with a distillation range of 60-80℃ and cycle the temperature from 0-60℃. The temperature change rate is 10℃ / min. The cycle periods are 100, 300 and 500 cycles respectively. After the cycle, take out the sample and dry it with hot air at 60℃ for 5h. Weigh it again and record it as M1. Then calculate the leakage rate = (M0-M1) / M0×100%; The specific test results are shown in Table 1:

[0037] It can be seen from the test results in Table 1 that the paraffin microcapsules prepared in the embodiment and the polyurea-coated paraffin-type phase change material in the comparative example have similar latent heat of fusion, and both reach 100 J / g, which meets the application of building energy storage materials. The compressive strength of the energy storage building material using paraffin microcapsules in the embodiment is slightly higher than that of the comparative example, and the leakage rate in the cycle test is much lower than that of the comparative example, showing excellent stability.

[0038] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0039] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A PCM-based energy storage building material, characterized in that: The materials include, by weight: 55-70 parts of ordinary Portland cement, 10-20 parts of aluminate cement, 10-15 parts of gypsum, 140-170 parts of fine aggregate, 15-25 parts of mineral powder, 18-26 parts of paraffin microcapsules, 5-7 parts of redispersible rubber powder, 0.8-1 parts of water reducing agent and 75-83 parts of water; The paraffin microcapsules are prepared by the following method: Step A1: premix pentamethylene glycol, triethylamine and anhydrous tetrahydrofuran, dry nitrogen protection, control the water bath temperature at 10-20°C, slowly add methylvinyldichlorosilane and stir to react for 1.5-2h, then add propylene diamine, raise the temperature to 45-55°C and stir to react for 30-40min, after the reaction is completed, remove tetrahydrofuran by rotary evaporation to obtain an intermediate; Step A2: Mix the intermediate, thioglycolic acid, photoinitiator and acetone, protect with nitrogen, and apply 150-200W / m 2 UV irradiation, stirring and reacting for 5-7 hours, after the reaction is completed, acetone is evaporated under reduced pressure to obtain a modifier; Step A3: preheat the paraffin and the modifier to dissolve, add deionized water to shear and disperse, control the temperature of the water bath to 50-60°C, stir and slowly add isophorone diisocyanate to react for 1-1.5h, then add calcium oxide and continue stirring for 2-3h, cool and filter to remove the water phase after the reaction, wash the substrate with water and vacuum dry to obtain paraffin microcapsules.

2. The PCM-based energy storage building material according to claim 1, characterized in that: The feed ratio of methylvinyldichlorosilane, pentamethylene glycol, propylenediamine, triethylamine and anhydrous tetrahydrofuran is 0.1 mol: 80-90 mmol: 15-30 mmol: 6-10 mL: 45-55 mL.

3. The PCM-based energy storage building material according to claim 2, characterized in that: The feed ratio of the intermediate, thioglycolic acid, photoinitiator and acetone is 10 g: 35-50 mmol: 10-15 mg: 40-50 mL.

4. The PCM-based energy storage building material according to claim 3, characterized in that: The feeding ratio of paraffin wax, modifier, isophorone diisocyanate, calcium oxide and deionized water is 50g:4.5-6g:2.2-2.8g:12-16g:130-160mL.

5. The PCM-based energy storage building material according to claim 1, characterized in that: The fine aggregate is machine-made sand with a fineness modulus of 1.7-2.

5.

6. The PCM-based energy storage building material according to claim 1, characterized in that: Mineral powder is a mixture of limestone powder and fly ash.

7. The PCM-based energy storage building material according to claim 1, characterized in that: The water reducing agent is a polycarboxylic acid water reducing agent.

8. A method for preparing a PCM-based energy storage building material according to any one of claims 1 to 7, characterized in that: Specifically, ordinary Portland cement, aluminate cement, gypsum, mineral powder, paraffin microcapsules and redispersible rubber powder are premixed, and then fine aggregate is added to mix evenly. Then, the water reducer is dispersed in water and added to the mixture and mixed evenly to obtain PCM-based energy storage building materials.

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