Energy-saving turnover intelligent window

Abstract

The invention discloses an energy-saving turnover intelligent window which comprises three window panels (1), a first cavity (2), a second cavity (3), a thermochromic energy storage material (4) and a turnover device (6), wherein the three window panels (1) are arranged at intervals, the peripheries of the three window panels (1) are sealed, the first cavity (2) and the second cavity (3) are formed by the window panels, the thermochromic energy storage material (4) is packaged in the first cavity, and the turnover device (6) is installed on the window panels and a window frame (5). The window panel is made of transparent glass or plastic through which sunlight can pass; the critical color change temperature of the thermochromic energy storage material is 20-40 DEG C, the thermochromic energy storage material is composed of a thermochromic material, energy storage gel and a light absorption material, and the thermochromic material is composed of a polyether surfactant and a cosolvent. The manufacturing process is simple, color change and energy storage are conducted at the same time, the response speed is high, the adjustable temperature range is wide, and all-weather temperature adjustment and energy saving in summer and winter are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of building energy-saving smart windows, and in particular to an energy-saving flip smart window and a thermochromic energy storage material. Background Art

[0002] Windows are the main channel for heat exchange between buildings and the outside environment, and their performance is related to building energy consumption. In recent years, smart windows are divided into four major systems: thermochromic, photochromic, electrochromic, and gas-chromic. They all adjust sunlight and indoor temperature by sensing external temperature and light intensity.

[0003] During the manufacturing process of electrochromic glass, contaminated particles with a particle size of micrometers penetrate the electrolyte layer, causing internal contamination. During use, the uneven discoloration of the material due to local short circuits reduces the cycle performance and shortens the service life. The ECD device used in the preparation (700 USD / m 2 ) is expensive, and requires magnetron sputtering equipment, high cleanliness, and multi-cavity structure materials or devices. The cost of large-scale production is very high. After repeated color changes, the signal-to-noise ratio of photochromic glass decreases, and its poor thermal stability and oxidation resistance, low photosensitivity, and low fatigue resistance limit the number of cycles it can be used, and the cost is high.

[0004] Existing thermochromic glass systems, such as vanadium dioxide thermochromic smart glass, have a film deposition temperature of more than 400°C in VO2-based thermochromic smart windows, a visible light transmittance of less than 35%, a sunlight regulation efficiency of less than 10%, and are easily oxidized and lose their energy-saving effects. The VO2 single-layer film will lose its dimming ability after 200 hours of aging.

[0005] The existing thermochromic hydrogel smart window has a phase change temperature of 32.5℃~43.5℃, which is relatively high, poor weather resistance stability, and a response time of usually more than 45 minutes. The patent with publication number CN115503307A and invention name: Photothermal dual response smart window and preparation method thereof uses a thermosensitive amide hydrogel sandwiched between two adjacent window panels and a solid hydrogel with light-absorbing nanoparticles or light-absorbing dyes added and evenly dispersed. The smart window has the following shortcomings: 1. A single layer can block up to 60% of sunlight, and can cool the room by a maximum of 10°C in summer, but has no special insulation function in winter; 2. The amount of hydrogel used in the smart window is relatively high, resulting in a slow response speed (1 to 15 minutes). In colder areas, the window will lose its ability to adjust even when the sunlight is strong; 3. The inability to flip makes it impossible for the window to adjust according to changes in external light, which may have a counterproductive effect in winter, and it is impossible to achieve all-weather energy saving and adjustment; 4. Compared with the material of the present invention, the monomer cost of the thermosensitive amide hydrogel is very high, the production process is complicated, and it cannot be produced on a large scale. Summary of the invention

[0006] The purpose of the present invention is to solve the deficiencies of the prior art and to provide an energy-saving flip smart window with a simple manufacturing process, fast response speed for simultaneous color change and energy storage, a wide adjustable temperature range, and the ability to achieve all-weather temperature regulation and energy saving.

[0007] The technical solution adopted by the present invention is as follows: An energy-saving flip smart window comprises three window panels spaced apart from each other and having peripheral seals, a first cavity formed by the window panels and a second cavity subjected to vacuum treatment, a thermochromic energy storage material encapsulated in the first cavity, and a flip device (6) installed on the window panels and a window frame (5); the window panels are made of transparent glass or plastic through which sunlight can pass; The thermochromic energy storage material of the present invention has a critical color change temperature of 20°C to 40°C and is composed of a thermochromic material, an energy storage gel and a light absorbing material. The thermochromic material is composed of a polyether surfactant and a cosolvent.

[0008] Furthermore, the polyether surfactant described in the present invention is one or a mixture of low-foam polyether, propylene glycol block polyether, EO / PO block modified polyether; the cosolvent is one or a mixture of alcohols such as methanol, ethanol, propylene glycol, etc.

[0009] Furthermore, the energy storage gel described in the present invention is any one of polyvinyl alcohol-based hydrogel, sodium alginate-based hydrogel, and 2-hydroxyethyl methacrylate (HEMA)-based hydrogel, or a mixture of several of them.

[0010] Furthermore, the light-absorbing material described in the present invention is any one of graphene oxide, graphene, MXene, or a mixture of two of them, and the concentration of the light-absorbing material in the thermochromic energy storage material is 10PPM to 200PPM.

[0011] Furthermore, the thickness of the first cavity of the present invention is 5 to 20 mm, and the thickness of the second cavity is 0.5 to 10 mm.

[0012] The present invention also provides a method for preparing a thermochromic energy storage material, comprising the following steps: S1. Prepare thermochromic material: add cosolvent to polyether surfactant, stir and mix evenly at a temperature of 20°C to 40°C, wherein the mass ratio of the polyether surfactant to the cosolvent is 1:(1.9 to 2.1); S2, mixing the thermochromic material and the energy storage gel described in S1 and stirring them evenly to form a mixture, wherein the mass ratio of the thermochromic material to the energy storage gel is 1:(3-5); S3, adding the light absorbing material to the mixture in S2 and stirring evenly to obtain a thermochromic energy storage material.

[0013] A method for preparing an energy-saving flip smart window of the present invention comprises the following steps: (1) Three window panels are arranged at intervals to form a first cavity and a second cavity. The three window panels are sealed on all sides, and the second cavity is evacuated to a pressure of <10 -1 Pa, the first cavity has a reserved injection port; (2) injecting the thermochromic energy storage material into the first cavity from the injection port and sealing the injection port to obtain an energy-saving smart window; (3) A flip device is movably installed on the outer side of the window panel of the energy-saving smart window described in step (2) and the upper and lower inner sides or the left and right inner sides of the window frame to obtain an energy-saving flip smart window.

[0014] Furthermore, the flipping device described in the present invention is a short shaft installed on the upper and lower inner sides or the left and right inner sides of the window frame and movably connected to the outer side of the window panel.

[0015] Beneficial effects of the present invention: 1. The polyether surfactant and cosolvent used in the present invention are compounded to form a stable suspension, so that the light-absorbing material is evenly dispersed therein, the color change time is shortened and the response speed is accelerated. The system realizes reversible changes with the change of ambient temperature. At low temperatures, the thermochromic material is hydrophilic and changes to hydrophobic at high temperatures, that is, the solubility is good at low temperatures. As the temperature increases, the solubility gradually decreases until it reaches the turbidity point. At this time, the solution becomes turbid and changes color when the temperature reaches the turbidity point, and the adjustable temperature range is wide.

[0016] 2. The present invention improves the transparency of the hydrogel (polyvinyl alcohol (PVA) hydrogel, sodium alginate-based hydrogel, 2-hydroxyethyl methacrylate (HEMA)-based hydrogel prepared by three freeze-thaw cycles and evacuates the second cavity to increase the energy storage function, realizes 180-degree rotation or 360-degree flipping through short-axis rotation, switches the illumination surface in summer and winter, and realizes energy saving all year round.

[0017] 3. If Figure 3 As shown, in the present invention, in summer, the first cavity of the window panel is turned to the outside, and sunlight shines on the window panel. When the window temperature rises to the response temperature, it changes color quickly. At this time, most of the sunlight will be refracted or reflected to reduce the heat entering the room, and a small part of the sunlight passes through the thermochromic energy storage material layer and is absorbed. The second cavity of the window panel is a vacuum layer, which greatly reduces the entry of the outside hot temperature, makes the indoor temperature balanced and stable, and saves energy consumption; Figure 4 As shown, in winter, the first cavity of the window panel is flipped inward, and sunlight enters the room through the vacuum layer of the second cavity to provide good lighting. The indoor heat is absorbed and stored by the thermochromic energy storage material layer, reducing heat loss to the outside. While maintaining the indoor temperature, the thermochromic material effectively blocks the light when the sunlight is strong, ensuring the comfort of the human eyes indoors. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 2 is a schematic diagram of the structure of the present invention; Figure 2 It is a partial cross-sectional view of the energy-saving flip smart window of the present invention; Figure 3 This is the energy storage and temperature regulation principle diagram of the energy-saving flip smart window of the present invention in summer: Figure 4 This is a schematic diagram of the energy storage and temperature regulation principle of the energy-saving flip smart window of the present invention in winter; Figure 5 1 is a state diagram of the energy-saving flip smart window of Example 1 of the present invention when it is light-transmissive at normal temperature and when it is light-impermeable at high temperature; Figure 6 This is a temperature change diagram of the energy-saving flip smart window in Example 2 of the present invention under a simulated summer temperature environment throughout the day; Figure 7 This is a temperature change diagram of the energy-saving flip smart window in Example 3 of the present invention under a simulated winter temperature environment; Figure 8 The energy-saving flip smart windows of Examples 1 to 3 of the present invention are heated to 20° C. and 60° C. respectively to simulate an extreme ambient temperature, and the temperature change diagram is 24 hours. DETAILED DESCRIPTION

[0019] The present invention will be described in further detail below in conjunction with the accompanying drawings. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope limited by the appended claims of the application.

[0020] Example 1

[0021] Please see Figure 1 and Figure 2 First, the glass panels are arranged at intervals of 5 mm in thickness of the first cavity and 0.5 mm in thickness of the second cavity, an injection port of the thermochromic energy storage material is left in the first cavity, the glass is sealed around with waterproof glass glue, and the second cavity is evacuated to a pressure of 0.05 Pa; Preparation of thermochromic material: adding methanol to low-foam polyether, and mixing at a temperature of 20° C., wherein the mass ratio of the low-foam polyether to methanol is 1:1.9; Preparation of energy storage gel: polyvinyl alcohol with a degree of alcoholysis of 99% and a viscosity of 23-28 cps is prepared into a 10% PVA aqueous solution, dimethyl sulfoxide is introduced to make the mass fraction of polyvinyl alcohol 20%, and the ratio of water to dimethyl sulfoxide is 20 / 80; the heating and mixing process is maintained at 90°C for 4 hours, the cooling temperature is -10°C to -30°C, the freezing time is 6 hours, and then thawed at room temperature for 2 hours, and the heating-cooling-freezing-thawing process is repeated 3 times to obtain PVA hydrogel; The thermochromic material and the energy storage gel are mixed evenly at a mass ratio of 1:3. Add the light absorbing material to the above mixture and stir evenly, the concentration of the light absorbing material in the thermochromic energy storage material is 10 PPM to obtain a thermochromic energy storage material with a critical color change temperature of 20° C. Injecting a thermochromic energy storage material from an injection port of the first cavity and sealing the injection port to obtain an energy-saving flip smart window; The energy-saving flip smart window is obtained by movably installing a short shaft on the upper and lower inner sides or the left and right inner sides of the window frame and the outer side of the energy-saving smart window. The flip device can also use the existing technology to flip the window panel up and down or rotate left and right. At the same time, a frame can be reinforced on the outer side of the energy-saving smart window.

[0022] like Figure 5 As shown, the LS183 optical transmittance measurement method was used to measure the visible light transmittance of the thermochromic energy storage material before response, which was 94%. After response, it became milky white, and the sunlight transmittance was 14%, shielding 78% of sunlight.

[0023] When the energy-saving flip smart window of the present invention is used to make a glass house and simulates the summer temperature, the present invention can effectively reduce the temperature by 14°C compared with ordinary windows; when simulating the winter temperature, the present invention can effectively increase the temperature by 3°C compared with ordinary windows.

[0024] Example 2

[0025] Please see Figure 1 and Figure 2 First, the glass panels are arranged at intervals of 20 mm in thickness of the first cavity and 5 mm in thickness of the second cavity, an injection port of the thermochromic energy storage material is left in the first cavity, the glass is sealed around with waterproof glass glue, and the second cavity is evacuated to a pressure of 0.08 Pa; Preparation of thermochromic material: adding propylene glycol to propylene glycol block polyether, mixing at a temperature of 40° C., wherein the mass ratio of the low-foam polyether to methanol is 1:2.1; Preparation of energy storage gel material: adding gelatin to 2% sodium alginate, wherein the mass ratio of gelatin to sodium alginate is 1:3; heating to maintain at room temperature 20°C, and cooling at 2°C; The thermochromic material and the energy storage gel material are uniformly mixed in a mass ratio of 1:5; Adding light-absorbing material into the mixture and stirring evenly, the concentration of the light-absorbing material in the thermochromic energy storage material is 50 PPM to obtain a thermochromic energy storage material with a critical color change temperature of 40° C.; The thermochromic energy storage material is injected from the injection port of the first cavity and the injection port is sealed to obtain an energy-saving flip smart window; The energy-saving flip smart window is obtained by movably installing a short shaft on the upper and lower inner sides or the left and right inner sides of the window frame and the outer side of the energy-saving smart window. The flip device can also use the existing technology to flip the window panel up and down or rotate left and right. At the same time, a frame can be reinforced on the outer side of the energy-saving smart window.

[0026] The LS183 optical transmittance measurement method was used to measure the visible light transmittance of the thermochromic energy storage material before it responded to 94.1%. After the response, it was milky white, and the sunlight transmittance was 16%, shielding 80% of the sunlight. When the energy-saving flip smart window of the present invention is used to make a glass house and simulates the summer temperature, the present invention can effectively reduce the temperature by 16°C compared with ordinary windows; when simulating the winter temperature, the present invention can effectively increase the temperature by 5°C compared with ordinary windows.

[0027] Example 3

[0028] Please see Figure 1 and Figure 2 First, the glass panels are arranged at intervals of 10 mm in thickness of the first cavity and 5 mm in thickness of the second cavity, an injection port of the thermochromic energy storage material is left in the first cavity, the glass is sealed around with waterproof glass glue, and the second cavity is vacuumed to a pressure of 0.05 Pa; Preparation of thermochromic material: adding ethanol to EO / PO block modified polyether, mixing at a temperature of 25° C., wherein the mass ratio of the low-foam polyether to methanol is 1:2; Preparation of energy storage gel material: Add ammonium persulfate initiator to the monomer hydroxyethyl methacrylate solution, wherein the content of ammonium persulfate is 1.0% (w / V) of the monomer, SDS is 4.0% (w / V), and MBA is 4.0% (w / V), and the mixture is heated to 35°C and cooled to 0°C to obtain 2-hydroxyethyl methacrylate (HEMA); The thermochromic material and the energy storage gel material are uniformly mixed in a mass ratio of 1:4; Add the light absorbing material into the mixture and stir evenly, wherein the concentration of the light absorbing material in the thermochromic energy storage material is 80 PPM to obtain a thermochromic energy storage material with a critical color change temperature of 25° C.; The thermochromic energy storage material is injected from the injection port of the first cavity and the injection port is sealed to obtain an energy-saving flip smart window; The energy-saving flip smart window is obtained by movably installing a short shaft on the upper and lower inner sides or the left and right inner sides of the window frame and the outer side of the energy-saving smart window. The flip device can also use the existing technology to flip the window panel up and down or rotate left and right. At the same time, a frame can be reinforced on the outer side of the energy-saving smart window.

[0029] The LS183 optical transmittance measurement method was used to measure the visible light transmittance of the thermochromic energy storage material before it responded to 94.4%. After the response, it was milky white, and the sunlight transmittance was 15%, shielding 81% of the sunlight. When the energy-saving flip smart window of the present invention is used to make a glass house and simulates the summer temperature, the present invention can effectively reduce the temperature by 15° C. compared with ordinary windows; when simulating the winter temperature, the present invention can effectively increase the temperature by 4° C. compared with ordinary windows.

[0030] Comparative Example 1

[0031] A cavity with a thickness of 5.5 mm was set between the two glass panels and an injection port was left, which was sealed on all sides with waterproof glass glue, and the thermochromic energy storage material prepared in Example 1 was injected into the cavity to obtain a smart window.

[0032] The summer ambient temperature and winter ambient temperature were simulated for the glass house constructed with the smart windows prepared in Examples 1 to 3 and Comparative Example 1, and the test results of each performance are shown in Table 1: The light transmittance and light blocking rate were measured using LS183 optical transmittance measurement; Thermal insulation is tested using a portable energy-saving glass on-site comprehensive testing system: Table 1 Test results of various properties of glass houses constructed with smart windows prepared in Examples 1 to 3 and Comparative Example 1

[0033] Simulate the temperature changes of the whole day in the summer temperature environment Figure 6 As shown, the temperature change of the energy-saving flip smart window of the present invention and the smart window of comparative example 1 is 4°C; the temperature change of all-weather in the simulated winter temperature environment is as follows Figure 7 As shown, the energy-saving flip smart window of the present invention has a glass room temperature 1°C higher than that of the smart window of comparative example 1 and has a longer heat storage time.

[0034] like Figure 8 As shown, the energy-saving flip smart windows of Examples 1 to 3 of the present invention have significant heat blocking properties and obvious heat storage advantages. At the same time, the thermochromic energy storage material of the present invention has good stability and tolerance, and still has obvious heat storage advantages when used in an extreme environment simulated at 60°C, with a gentle temperature rise.

[0035] The above embodiments are merely descriptions of preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. An energy-saving flip smart window, characterized in that: The invention comprises three window panels (1) which are spaced apart and sealed at their peripheries, a first cavity (2) formed by the window panels and a second cavity (3) which is subjected to a vacuum treatment, a thermochromic energy storage material (4) encapsulated in the first cavity, and a turning device (6) installed on the window panels and the window frame (5); the window panels are made of transparent glass or plastic through which sunlight can pass; The thermochromic energy storage material has a critical color change temperature of 20° C. to 40° C. and is composed of a thermochromic material, an energy storage gel and a light absorbing material. The thermochromic material is composed of a polyether surfactant and a cosolvent.

2. The energy-saving flip smart window according to claim 1, characterized in that: The polyether surfactant is one or a mixture of low-foam polyether, propylene glycol block polyether, EO / PO block modified polyether; the cosolvent is one or a mixture of methanol, ethanol, and propylene glycol.

3. The energy-saving flip smart window according to claim 1, characterized in that: The energy storage gel is any one of polyvinyl alcohol-based hydrogel, sodium alginate-based hydrogel, and 2-hydroxyethyl methacrylate-based hydrogel, or a mixture of several of them.

4. The energy-saving flip smart window according to claim 1, characterized in that: The light-absorbing material is any one of graphene oxide, graphene, and MXene, or a mixture of the two. The concentration of the light-absorbing material in the thermochromic energy storage material is 10PPM to 200PPM.

5. The energy-saving flip smart window according to claim 1, characterized in that: The thickness of the first cavity is 5-20 mm, and the thickness of the second cavity is 0.5-10 mm.

6. The energy-saving flip smart window according to any one of claims 1 to 5, characterized in that: The preparation method of the thermochromic energy storage material comprises the following steps: S1. Prepare thermochromic material: add cosolvent to polyether surfactant, stir and mix evenly at a temperature of 20°C to 40°C, wherein the mass ratio of the polyether surfactant to the cosolvent is 1:(1.9 to 2.1); S2, mixing the thermochromic material and the energy storage gel described in S1 and stirring them evenly to form a mixture, wherein the mass ratio of the thermochromic material to the energy storage gel is 1:(3-5); S3, adding the light absorbing material to the mixture in S2 and stirring evenly to obtain a thermochromic energy storage material.

7. The method for preparing an energy-saving flip smart window according to claim 6, characterized in that: The steps include: (1) Three window panels are arranged at intervals to form a first cavity and a second cavity. The three window panels are sealed on all sides, and the second cavity is evacuated to a pressure of <10 -1 Pa, the first cavity has a reserved injection port; (2) injecting the thermochromic energy storage material into the first cavity from the injection port and sealing the injection port to obtain an energy-saving smart window; (3) A flip device is movably installed on the outer side of the window panel of the energy-saving smart window described in step (2) and the upper and lower inner sides or the left and right inner sides of the window frame to obtain an energy-saving flip smart window.

8. The energy-saving flip smart window according to claim 7, characterized in that: The turning device is a short shaft installed on the upper and lower inner sides or the left and right inner sides of the window frame and movably connected to the outer side of the window panel.

Images