Intelligent window system based on photochromic shape memory polymer and application

Abstract

The invention provides an intelligent window system based on a photochromic shape memory polymer and application. The intelligent window system comprises a window body, a functional layer located on glass, an executing mechanism, a sensing module and a control module. The functional layer is composed of a composite film and a self-driven intelligent assembly; the composite film comprises a color changing layer made of a photochromic material and a deformation layer made of a shape memory polymer, and the self-driven intelligent assembly is made of the shape memory polymer; the self-driven intelligent assembly is in a strip shape and located on one side of the composite film. One end is fixedly connected to the first frame body of the window body, and the other end is connected with the execution mechanism; the self-driven intelligent assembly deforms when reaching the glass-transition temperature of the shape memory polymer and drives the execution mechanism to move so as to achieve opening and closing of the window body. The sensing module is used for acquiring environmental parameters; the control module is used for receiving the environment parameters and determining weather changes at the future moment so as to issue a control instruction for opening and closing the window based on the environment parameters and the weather changes. According to the scheme, the intelligent window is low in energy consumption and high in reliability and has the weather prediction function.

Description

Technical Field

[0001] This invention relates to the field of smart window system technology, and more particularly to the field of smart materials technology, and especially to a smart window system and application based on photochromic shape memory polymer. Background Technology

[0002] Smart window systems, as an important technology in green building, have been widely used in energy conservation and comfort regulation. Existing smart windows mostly focus on the window's response to changes in light or temperature, but few systems can predict weather changes or adapt in real time to complex meteorological conditions, resulting in a poor user experience.

[0003] Therefore, there is an urgent need to develop a smart window system and application based on photochromic shape memory polymers. Summary of the Invention

[0004] This invention provides an intelligent window system and application based on photochromic shape memory polymer. The system can respond to multiple environmental changes simultaneously and has weather forecasting capabilities, thereby improving the user experience.

[0005] In a first aspect, the present invention provides an intelligent window system based on photochromic shape memory polymer, comprising: a window body, a functional layer on the glass of the window body, an actuator, a sensing module and a control module; The functional layer consists of a composite film and a self-driven intelligent component; the composite film includes an outward-facing color-changing layer made of a photochromic material and an inward-facing deformation layer made of a shape memory polymer, and the self-driven intelligent component is made of the shape memory polymer. The self-driven intelligent component is strip-shaped and located on one side of the composite film, parallel to the left and right frames of the window body; one end of the self-driven intelligent component is fixedly connected to the first frame of the window body, and the other end is connected to the actuator. The actuator is used to control the opening and closing of the window body; wherein, the self-driven intelligent component deforms when the glass transition temperature of the shape memory polymer is reached, and drives the actuator to move, so as to realize the opening and closing of the window body; The sensing module is used to acquire environmental parameters; the control module is connected to the sensing module; the control module is used to receive the environmental parameters and determine the weather changes at future times, so as to implement control commands for opening and closing the window based on the environmental parameters and the weather changes.

[0006] Preferably, the photochromic material is prepared by the following method: Azobenzene monomer is dissolved in a first solvent, and then matrix monomer and crosslinking agent are added and mixed to obtain a mixed solution; an initiator is added to the mixed solution to initiate a polymerization reaction to obtain the photochromic material.

[0007] More preferably, the polymerization reaction is carried out at a temperature of 60-80°C for a time of 4-6 hours.

[0008] More preferably, the azobenzene monomer is 4,4'-diaminoazobenzene; the matrix monomer is acrylic acid or polymethacrylic acid; the crosslinking agent is divinylbenzene; and the initiator is phenyl peroxide.

[0009] More preferably, the mass ratio of the azobenzene monomer to the matrix monomer is 1:(2~3).

[0010] More preferably, the amount of the crosslinking agent is 1 wt% to 3 wt% of the sum of the mass of the azobenzene monomer and the matrix monomer.

[0011] More preferably, the amount of the initiator is 1 wt% to 2 wt% of the amount of the azobenzene monomer.

[0012] Preferably, the shape memory polymer is obtained by crosslinking polylactic acid and epoxy acrylate.

[0013] More preferably, the amount of epoxy acrylate used is 1wt% to 10wt% of the amount of polylactic acid used.

[0014] More preferably, the deformable layer is prepared by the following method: The polylactic acid is dissolved in a second solvent, and then epoxy acrylate is added and mixed to obtain a mixed solution. The mixed solution is poured into a mold, and after the second solvent evaporates, a pre-made film is obtained. The pre-made film is then heat-treated to complete cross-linking, and the deformable layer is obtained.

[0015] Preferably, the composite film is prepared by the following method: (1) The photochromic material is formed into the color-changing layer by solution casting; wherein the cross-section of the color-changing layer is triangular or trapezoidal; (2) The color-changing layer and the deformation layer are hot-pressed at a mass ratio of 1:1 to obtain the composite film; wherein the cross-section of the color-changing layer is a triangle or trapezoid that matches the color-changing layer, so that the cross-section of the composite film is rectangular; and the content of shape memory polymer is different in different thickness directions.

[0016] More preferably, the hot pressing is performed at 80~100℃ and 0.2~0.5MPa for 10~20min.

[0017] More preferably, the thickness of the composite film is 0.2~0.4 mm.

[0018] Preferably, the functional layer is located in the hollow region of the hollow glass structure.

[0019] Preferably, when the window body is in the closed state, the functional layer completely covers the glass; when the window body is in the open state, the functional layer does not cover the glass; wherein, the composite film deforms synchronously with the self-driven intelligent component.

[0020] More preferably, the deformable layer is integrally formed with the self-driven intelligent component.

[0021] Preferably, the functional layer includes at least one of the self-driven intelligent components; The self-driven intelligent component is located on one side adjacent to the window hinge, the first frame is the lower frame, and the actuator is hidden in the frame.

[0022] Preferably, the system further includes a heating module, which is connected to the control module; The heating module is used to receive control commands from the control module and heat the functional layer so that the self-driven intelligent component deforms when it reaches the glass transition temperature, and drives the actuator to move to realize the opening and closing of the window body.

[0023] Preferably, the sensing module includes at least one of a light sensor, a temperature sensor, and a humidity sensor; The light sensor is a photoresistor or a photodiode, which is installed on the top of the outer side of the window frame of the window body to obtain the light intensity. The temperature sensors are respectively installed on the outer surface of the window body and on the indoor side near the window body, and are used to obtain the indoor temperature and the outdoor temperature. The humidity sensor is installed outdoors to obtain outdoor humidity.

[0024] Preferably, the system further includes: a light-shielding module and an ultraviolet light irradiation module; The control module is also used to send a shading command to the shading module when the light intensity exceeds a first preset light intensity threshold, in order to adjust the amount of light entering the room and control the degree of color change of the color-changing layer; and to send an illumination command to the ultraviolet light module when the light intensity is lower than a second preset light intensity threshold, in order to restore the color-changing layer to its original color. The control module is also used to issue the control command to adjust the opening degree of the window body when the difference between the indoor temperature and the outdoor temperature exceeds a preset temperature threshold. The control module is also used to issue the control command to adjust the opening degree of the window body when the difference between the outdoor humidity and the indoor humidity exceeds a preset humidity threshold.

[0025] Preferably, the control module is used to calculate the environmental change value per unit time based on the environmental parameters acquired in real time, and when the environmental change value exceeds a preset change threshold, it determines that there will be weather changes in the future, and then issues the control command to close the window body; wherein, the environmental parameters include light intensity, indoor temperature, outdoor temperature and outdoor humidity.

[0026] Preferably, the control module is used to issue control commands based on the environmental parameters and a preset rule base; wherein the preset rule base stores control commands for different environmental parameters.

[0027] Secondly, an application of the intelligent window system based on the first aspect above, wherein the application method includes: Obtain the environmental parameters of the window itself; Determine future weather changes based on the environmental parameters; Based on the weather changes at the future moment, current environmental parameters, and user needs, control commands are determined to control the opening and closing of the window body and the color change of the color-changing layer.

[0028] Compared with the prior art, the present invention has at least the following beneficial effects: (1) The intelligent window system based on photochromic shape memory polymer provided by the present invention integrates a color-changing layer based on photochromic material, a deformation layer based on shape memory polymer, and multiple sensors and intelligent control modules for acquiring environmental parameters in the same window body. This enables coordinated response of multiple physical fields, including light, temperature, and humidity. It can not only make real-time adjustments based on the current environmental parameters, but also make predictive responses to the upcoming weather conditions based on environmental parameters over a period of time. Thus, it upgrades from passively following the weather to a perceptible, predictable, and adjustable intelligent window system, improving the window's adaptability in different environments, reducing the impact of external weather on the indoor environment, achieving the dual effects of energy saving and improving indoor comfort, and significantly improving the user experience.

[0029] (2) The present invention utilizes the reversible color change and shape memory characteristics of photochromic materials to undertake the main adjustment function. It only relies on low-power sensors and control modules to complete the status recognition and command output. It can maintain the color state and opening and closing form of the window without continuous high-power drive, thereby significantly improving the building energy-saving effect and indoor environmental quality in terms of reducing glare, optimizing indoor lighting, reducing cooling / heating load, and improving ventilation and humidity comfort.

[0030] (3) The functional layer provided by the present invention can be used as a sandwich or attached layer and is compatible with existing insulated glass and curtain wall systems, making it easy to promote its engineering on existing buildings; and can be connected to building automation and smart home platforms to provide a smart window with low energy consumption, high reliability and visual weather response for multiple application scenarios such as green buildings and greenhouses. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the structure of an intelligent window system based on photochromic shape memory polymer according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a cross-section of a composite film provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of a window body in an open state according to an embodiment of the present invention; Figure 4 This is a schematic diagram of another intelligent window system based on photochromic shape memory polymer provided in an embodiment of the present invention; Reference numerals: 10-Window body; 20-Functional layer; 30-Actuator; 40-Sensing module; 50-Control module; 200-Composite film; 202-Self-driven intelligent component; 2001-Color-changing layer; 2002-Deformation layer; 60-Heating module; 70-Light-shielding module; 80-Ultraviolet light module. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0034] The following describes the specific implementation of the concept in this application.

[0035] Please refer to Figure 1This invention provides an intelligent window system based on photochromic shape memory polymer, comprising: a window body 10, a functional layer 20 located on the glass of the window body, an actuator 30, a sensing module 40, and a control module 50. The functional layer 20 is composed of a composite film 200 and a self-driven intelligent component 202; the composite film 200 includes an outwardly facing color-changing layer 2001 made of photochromic material and an inwardly facing deformation layer 2002 made of shape memory polymer; the self-driven intelligent component 202 is made of shape memory polymer. The self-driven intelligent component 202 is strip-shaped and located on one side of the composite film 200, parallel to the left and right frames of the window body 10; one end of the self-driven intelligent component 202 is fixedly connected to the first frame of the window body 10, and the other end is connected to the actuator 30. The actuator 30 is used to control the opening and closing of the window body 10; wherein, the self-driven intelligent component 202 deforms when it reaches the glass transition temperature of the shape memory polymer and drives the actuator 30 to move, so as to realize the opening and closing of the window body 10. The sensing module 40 is used to acquire environmental parameters; the control module 50 is connected to the sensing module 40; the control module 50 is used to receive environmental parameters and determine the weather changes at future times, so as to issue control commands to realize the opening and closing of windows based on environmental parameters and weather changes.

[0036] It should be noted that the actuator can be connected to the control module. The actuator can be a resistance heating element integrated with the self-driven intelligent component, or a flexible conductive film with localized heating, so that the control module can directly control the actuator to open and close the window. The first frame is either an upper frame or a lower frame. It should be noted that... Figure 1 The window body is in a closed state, and the first frame is the lower frame.

[0037] In this embodiment of the invention, by integrating a color-changing layer based on photochromic materials, a deformation layer based on shape memory polymers, and multiple sensors and intelligent control modules for acquiring environmental parameters into the same window, a coordinated response to multiple physical fields, including light, temperature, and humidity, is achieved. This not only enables real-time adjustments based on current environmental parameters but also allows for predictive responses to upcoming weather conditions based on environmental parameters over a period of time. Thus, it upgrades from passively following the weather to a perceptible, predictable, and adjustable intelligent window system, improving the window's adaptability to different environments, reducing the impact of external weather on the indoor environment, achieving the dual effects of energy saving and improved indoor comfort, and significantly enhancing the user experience.

[0038] In a preferred embodiment, the photochromic material is prepared by the following method: Azobenzene monomer is dissolved in a first solvent, and then matrix monomer and crosslinking agent are added and mixed to obtain a mixed solution; an initiator is added to the mixed solution to initiate a polymerization reaction to obtain a photochromic material.

[0039] In a more preferred embodiment, the polymerization reaction is carried out at a temperature of 60-80°C (e.g., 60°C, 65°C, 70°C, 75°C or 80°C) for a time of 4-6 hours (e.g., 4 hours, 4.5 hours, 5 hours, 5.5 hours or 6 hours).

[0040] In a more preferred embodiment, the azobenzene monomer is 4,4'-diaminoazobenzene; the matrix monomer is acrylic acid or polymethacrylic acid; the crosslinking agent is divinylbenzene; and the initiator is phenyl peroxide.

[0041] In a more preferred embodiment, the mass ratio of azobenzene monomer to matrix monomer is 1:(2~3) (for example, it can be 1:2, 1:2.5 or 1:3).

[0042] In a more preferred embodiment, the amount of crosslinking agent is 1 wt% to 3 wt% of the sum of the mass of the azobenzene monomer and the matrix monomer (for example, it can be 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt% or 3 wt%).

[0043] In a more preferred embodiment, the amount of initiator is 1 wt% to 2 wt% of the amount of azobenzene monomer (e.g., it can be 1 wt%, 1.2 wt%, 1.5 wt%, 1.6 wt%, 1.8 wt% or 2 wt%).

[0044] Specifically, 4,4'-diaminoazobenzene is dissolved in ethanol at a concentration of 5wt%~10wt%, which is sufficient to ensure good photochromic effects. Then, acrylic acid and divinylbenzene are added and mixed thoroughly. Next, phenyl peroxide is added to initiate the polymerization reaction. The reaction temperature is controlled at 60~80℃, and the reaction time is 4~6 hours to ensure smooth reaction and obtain a polymer with high photochromic effect, i.e., a photochromic material. After the reaction, unreacted monomers are removed by precipitation, using cooling ethanol or water during the precipitation process to ensure the removal of impurities and unreacted substances. Then, the mixture is sequentially filtered and dried (continuously dried at 40℃ for 24 hours) to obtain the final photochromic material.

[0045] In this embodiment of the invention, the stability of the photochromic material is enhanced by adding the crosslinking agent in the above-mentioned amount, thereby improving the material's light stability and long-term durability. Experiments have shown that if the mass ratio of azobenzene monomer to matrix monomer is greater than 1:2, the amount of azobenzene monomer used is excessive. Although the color is deeper and the response may be stronger, the haze, brittleness, and fatigue degradation risk of the photochromic layer also increase. If the mass ratio of azobenzene monomer to matrix monomer is less than 1:3, the amount of azobenzene monomer used is too low. The color-changing layer is clearer and has better toughness, but the color-changing contrast decreases, making it difficult to respond quickly within a limited time.

[0046] In a preferred embodiment, the shape memory polymer is obtained by crosslinking polylactic acid and epoxy acrylate.

[0047] In a more preferred embodiment, the amount of epoxy acrylate is 1 wt% to 10 wt% of the amount of polylactic acid (e.g., it can be 1 wt%, 2 wt%, 3 wt%, 5 wt%, 6 wt%, 8 wt% or 10 wt%).

[0048] In a more preferred embodiment, the deformable layer is prepared by the following method: Polylactic acid is dissolved in a second solvent, and then epoxy acrylate is added and mixed to obtain a mixed solution. The mixed solution is poured into a mold, and after the second solvent evaporates, a pre-made film is obtained. The pre-made film is then heat-treated to complete cross-linking and obtain a deformable layer.

[0049] Specifically, polylactic acid (PLA) is dissolved in carbon tetrachloride at a concentration of 10wt%~15wt% to ensure a homogeneous solution free of particulate matter. Then, epoxy acrylate is added under magnetic stirring and thoroughly mixed to obtain a mixed solution. The mixed solution is poured into a mold, and the solvent is completely evaporated using a solvent evaporation method. The mold is then dried at room temperature for 24 hours until the preform is completely dry. The dried preform is then heat-treated at 120°C for 1 hour to ensure the material develops a shape memory effect, meaning it can recover to a preset shape at a specific temperature.

[0050] In this embodiment of the invention, the shape memory properties of the shape memory polymer are enhanced by adding a crosslinking agent. The glass transition temperature of this shape memory polymer is 30~60℃. Specifically, the glass transition temperature of the deformation layer can be appropriately adjusted under different application scenarios to ensure that the composite film and the self-driven smart component can deform rapidly. Testing shows that the shape memory polymer can recover its bent or straight shape within 5 seconds at 60℃, thus completing shape memory recovery.

[0051] In one specific embodiment, the UV resistance of the composite film can be enhanced by adding an anti-UV additive (e.g., titanium dioxide) and an antioxidant (e.g., butylated hydroxytoluene) to the photochromic material and shape memory polymer. The amount of the anti-UV additive is 1 wt% to 2 wt% of the photochromic material or shape memory polymer; the amount of the antioxidant is 0.5 wt% to 1 wt% of the photochromic material or shape memory polymer. This invention, through crosslinking design and the introduction of anti-UV additives and antioxidants, enables the composite film to possess high photostability, deformation cycle durability, and structural safety.

[0052] In a preferred embodiment, the composite film is prepared by the following method: (1) The photochromic material is made into a color-changing layer by solution casting; wherein the cross-section of the color-changing layer is triangular or trapezoidal; (2) The color-changing layer and the deformation layer are hot-pressed at a mass ratio of 1:1 to obtain a composite film; wherein the cross-section of the color-changing layer is a triangle or trapezoid that matches the color-changing layer so that the cross-section of the composite film is rectangular; and the content of shape memory polymer is different in different thickness directions.

[0053] Specifically, the cross-section of the composite film is as follows: Figure 2 As shown, the color-changing layer 2001 faces the outer side of the window, and the deformation layer 2002 faces the inner side of the window. Thus, the content of the shape memory polymer varies in a gradient along the direction perpendicular to the thickness direction. Preferably, the end of the self-driven intelligent component fixedly connected to the first frame of the window body is the fixed end, and the end connected to the actuator is the movable end. Therefore, the content of the shape memory polymer gradually increases from the position at the same height as the fixed end to the position at the same height as the movable end. Thus, the composite film has the highest content of shape memory polymer at the movable end, allowing for better synchronization of deformation with the self-driven intelligent component.

[0054] In a more preferred embodiment, the hot pressing is performed at 80~100°C (e.g., 80°C, 85°C, 90°C, 95°C or 100°C) and 0.2~0.5MPa (e.g., 0.2MPa, 0.3MPa, 0.4MPa or 0.5MPa) for 10~20 min (e.g., 10 min, 12 min, 15 min, 16 min, 18 min or 20 min).

[0055] In a more preferred embodiment, the thickness of the composite film is 0.2 to 0.4 mm (e.g., it can be 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm or 0.4 mm).

[0056] It should be noted that a small amount of coupling agent or adhesive can be sprayed between the color-changing layer and the deformation layer to further improve their adhesion.

[0057] In a preferred embodiment, the functional layer is located in the hollow region of the insulating glass structure.

[0058] Specifically, the functional layer includes, but is not limited to, being disposed on the glass surface or in the hollow area of ​​the insulated glass structure, preferably disposed in the hollow area of ​​the insulated glass structure.

[0059] In a preferred embodiment, such as Figure 1 As shown, when the window body is closed, the functional layer completely covers the glass; as Figure 3 As shown, when the window is open, the functional layer does not cover the glass; the composite film and the self-driven intelligent component deform synchronously. It should be noted that... Figure 1 The self-driven intelligent component is located on one side adjacent to the window hinge. The first frame is the lower frame, meaning its fixed end is located on the lower frame. The actuator is hidden in the upper frame. When the window body is closed, the movable end of the self-driven intelligent component is flush with the upper frame. Figure 3 The fixed end of the self-driven intelligent component in the middle and Figure 1 The positions of the fixed ends differ. Specifically, in Figure 3 In the middle, the self-driven intelligent component is located on one side adjacent to the window hinge. The first frame is the upper frame, meaning its fixed end is located on the upper frame. The actuator is hidden in the lower frame. When the window body is closed, the movable end of the self-driven intelligent component is flush with the lower frame; however, if the self-driven intelligent component deforms, such as... Figure 3 As shown, its movable end is no longer flush with the lower frame. It should be noted that... Figure 3 Self-driven intelligent components are not shown.

[0060] In this embodiment of the invention, when the window body is closed, the functional layer completely covers the glass. Then, external light first acts on the color-changing layer, causing it to change color. After absorbing the light, the color-changing layer transfers heat to the deformation layer until the glass transition temperature is reached. The deformation layer and the self-driven intelligent component deform synchronously. At this point, the self-driven intelligent component drives the actuator to open the window body. Because the functional layer is deformed, it fails to cover the glass. Thus, a gradient response chain from light to heat to deformation is achieved, enabling self-driven window opening without a traditional motor.

[0061] In a more preferred embodiment, the deformable layer is integrally formed with the self-driven smart component.

[0062] In a preferred embodiment, the functional layer includes at least one self-driving intelligent component; like Figure 1As shown, the self-driven intelligent component is located on one side adjacent to the window hinge, the first frame is the lower frame, and the actuator is hidden in the frame.

[0063] It should be noted that the actuator may be, but is not limited to, hidden in the upper frame or in the upper frame and the vertical frame of the adjacent window hinge.

[0064] In this embodiment of the invention, the thickness of the self-driven intelligent component is greater than the thickness of the composite film, but less than the thickness of the hollow region. Multiple self-driven intelligent components can also be provided to generate sufficient driving torque when the self-driven intelligent component bends or deforms, thereby driving the actuator to move and opening or closing the window sash.

[0065] In a preferred embodiment, such as Figure 4 As shown, the system also includes a heating module 60, which is connected to the control module 40; The heating module 60 is used to receive control commands from the control module 40 and heat the functional layer 20 so that the self-driven intelligent component 202 deforms when it reaches the glass transition temperature and drives the actuator 30 to move to realize the opening and closing of the window body 10.

[0066] In this invention, after the self-driven intelligent component deforms and opens the window, if it gets dark or the user needs to close the window, the heating module can drive the self-driven intelligent component to deform again to close the window. Alternatively, a spring component can be set up, and the control module can cause the spring component to rebound to close the window.

[0067] In a preferred embodiment, the sensing module includes at least one of a light sensor, a temperature sensor, and a humidity sensor; The light sensor is a photoresistor or a photodiode, which is installed on the top of the outer side of the window frame to obtain the light intensity. Temperature sensors are installed on the outer surface of the window body and on the indoor side near the window body to obtain indoor and outdoor temperatures. The humidity sensor is installed outdoors to obtain outdoor humidity.

[0068] It should be noted that the sensing module preferably includes a light sensor, a temperature sensor, and a humidity sensor.

[0069] Specifically, the light sensor monitors the intensity of light outside the window and controls the color change of the azobenzene polymer in the color-changing layer based on changes in light intensity. This directly affects the window's transparency, thereby regulating the amount of light entering the room. The light sensor uses either a photodiode or a photoresistor, enabling real-time detection of light intensity changes and offering advantages such as fast response and high accuracy. The commonly used measurement range is 0~2000 lux, adaptable to various lighting environments. The light sensor is installed on the exterior of the window or above the window frame, directly exposed to natural light to ensure accurate detection of outside light intensity.

[0070] Temperature sensors are used to monitor the temperature difference between indoors and outdoors, as temperature change is a crucial parameter for the response of shape memory polymers. When this temperature difference exceeds a preset temperature threshold, the control module adjusts the window's opening degree to optimize the indoor temperature. Commonly used temperature sensors include thermistors (NTCs), which are inexpensive, stable, and suitable for indoor temperature measurement. Temperature sensors can be placed on the inner and outer surfaces of the window, as well as in the gaps around the window frame, ensuring accurate measurement of the window's surface temperature and both indoor and outdoor temperatures.

[0071] Humidity sensors are used to monitor the humidity of the external environment. By combining data from temperature sensors, they can further optimize the window's response performance to adapt to weather conditions with high or low humidity. Humidity sensors typically use capacitive humidity sensors, which are highly accurate and have a rapid response. Humidity sensors can be installed in air-circulating areas near the window frame or directly exposed to the outside air to accurately detect changes in external humidity.

[0072] In a preferred embodiment, such as Figure 4 As shown, the system also includes: a light-shielding module 70 and an ultraviolet light module 80; The control module 40 is also used to send a shading command to the shading module 70 when the light intensity exceeds the first preset light intensity threshold, in order to adjust the amount of light entering the room and control the degree of color change of the color-changing layer; and to send an illumination command to the ultraviolet light module 80 when the light intensity is lower than the second preset light intensity threshold, in order to restore the color-changing layer to its original color. The control module 40 is also used to issue control commands to adjust the opening degree of the window body when the difference between the indoor temperature and the outdoor temperature exceeds a preset temperature threshold. The control module 40 is also used to issue control commands to adjust the opening degree of the window body when the difference between the outdoor humidity and the indoor humidity exceeds a preset humidity threshold.

[0073] It should be noted that the control module also needs to determine the current window status based on the previous control command, and then combine the current window status with the environmental parameters transmitted by the received sensors to further determine the specific control command.

[0074] In a preferred embodiment, the control module is used to calculate the environmental change value per unit time based on the environmental parameters acquired in real time, and when the environmental change value exceeds a preset change threshold, it determines that there will be weather changes in the future, and then issues a control command to close the window body; wherein, the environmental parameters include light intensity, indoor temperature, outdoor temperature, and outdoor humidity.

[0075] In this invention, environmental parameters acquired in real time are used to calculate the environmental change value per unit time within the current time period. This environmental change value includes changes in light intensity, outdoor temperature, and outdoor humidity. When these environmental change values ​​are too large and exceed their respective preset thresholds, it is determined that an impending weather change is imminent. For example, a sudden drop in sunlight under high humidity indicates impending rain, while rapid temperature increases under strong sunlight indicate a heat wave. Thus, when an impending weather change is determined, windows can be intelligently controlled to close in advance, thereby preventing losses for the user and avoiding situations where the user is not home and has not had time to close the windows. This represents a breakthrough from passive response to proactive predictive response, significantly improving the user experience.

[0076] In a preferred embodiment, the control module is used to issue control commands based on environmental parameters and a preset rule base; wherein the preset rule base stores control commands for different environmental parameters.

[0077] In this embodiment of the invention, environmental parameters include light intensity, indoor temperature, outdoor temperature, and outdoor humidity. By storing control commands under different environmental parameters in a preset rule base, control commands can be directly issued based on the environmental parameters and the preset rule base. Specifically, environmental parameters can be converted into fuzzy variables, and fuzzy rules in the processing rule base can be used to output window adjustment commands. Input fuzzification: The range of light intensity is divided into three categories: strong, medium, and weak; the range of temperature difference is divided into three categories: high, medium, and low. According to the preset rule base, for example, when the light intensity is strong and the temperature difference is high, a control command is issued to change the window color and open it.

[0078] This invention also provides an application based on the above-described intelligent window system, the application method of which includes: Obtain the environmental parameters of the window itself; Determine future weather changes based on environmental parameters; Based on future weather changes, current environmental parameters, and user needs, control commands are determined to control the opening and closing of the window body and the color change of the color-changing layer.

[0079] It should be noted that, preferably, setting user requirements takes precedence over setting current environment parameters.

[0080] In a preferred embodiment, the smart window system is applied in green buildings, greenhouse cultivation, museum display cases, and other places where light, temperature and humidity need to be controlled simultaneously and weather forecasting is required.

[0081] Specifically, multiple smart window systems are connected to the building automation platform via a bus or wireless network to achieve zoned and coordinated control of the exterior windows of the entire building.

[0082] In this invention, the use of "and / or" between multiple technical features indicates that these technical features are connected by an "and / or" relationship, meaning that it can be any one of these technical features, or any combination of two or more of these technical features.

[0083] The present invention will be further described below by way of examples, but the scope of protection of the present invention is not limited to these embodiments.

[0084] In the following examples, the mass amounts of each component in the shape memory composite material are expressed in parts by mass.

[0085] Example 1 like Figure 4 As shown, an intelligent window system based on photochromic shape memory polymer includes: a window body 10, a functional layer 20 located on the glass of the window body, an actuator 30, a sensing module 40, a control module 50, a heating module 60, a light-blocking module 70, and an ultraviolet light module 80. The functional layer 20 consists of a composite film 200 and a self-driven intelligent component 202; the functional layer is located in the hollow area of ​​the insulating glass structure; the composite film 200 includes an outward-facing photochromic layer 2001 made of photochromic material and an inward-facing deformation layer 2002 made of shape memory polymer; the self-driven intelligent component 202 is made of shape memory polymer; at this time, from the outdoor side to the indoor side, the following are arranged in sequence: outer tempered glass, 4 mm thick; photochromic layer 2001, 5~20 μm thick; deformation layer 2002, 100~300 μm thick; inner tempered glass, 4 mm thick; The self-driven intelligent component 202 is strip-shaped and located on one side of the composite film 200, parallel to the left and right frames of the window body 10, and located on the side adjacent to the window sash hinge; one end of the self-driven intelligent component 202 is fixedly connected to the lower frame of the window body 10, and the other end is connected to the actuator 30, which is hidden in the frame. The actuator 30 is used to control the opening and closing of the window body 10; wherein, the self-driven intelligent component 202 deforms when it reaches the glass transition temperature of the shape memory polymer and drives the actuator 30 to move, so as to realize the opening and closing of the window body 10. The sensing module 40 includes a light sensor, a temperature sensor, and a humidity sensor, used to acquire environmental parameters including light intensity, indoor temperature, outdoor temperature, and outdoor humidity. The light sensor is a photoresistor, installed on the top of the outer side of the window frame, with a measurement range of 0~2000 lux. The temperature sensor is an NTC thermistor, arranged on the outer surface of the window and near the window on the indoor side, respectively, to obtain the indoor and outdoor temperature difference. The humidity sensor is a capacitive humidity sensor, arranged in a well-ventilated location on the outside. The output signal of the sensing module 40 is connected to the intelligent control module 50 through wires or bus; the control module 50 adopts an STM32 microcontroller or equivalent microcontroller, including A / D acquisition circuit, memory and drive circuit; The control module 50 is connected to the sensing module 40, the heating module 60, the light-shielding module 70 and the ultraviolet light module 80 respectively; The control module 50 is used to receive environmental parameters and determine future weather changes, so as to issue control commands for opening and closing the window based on the environmental parameters and weather changes.

[0086] Photochromic materials are prepared by the following method: 4,4'-Diaminoazobenzene was dissolved in ethanol, at a concentration of 8 wt%. Then, acrylic acid (4,4'-diaminoazobenzene to acrylic acid mass ratio of 1:2) and divinylbenzene were added and mixed thoroughly. Phenyl peroxide was then added to initiate the polymerization reaction, controlling the reaction temperature at 60°C and the reaction time at 6 h. After the reaction, unreacted monomers were removed by precipitation, using cooling ethanol or water during the precipitation process to ensure the removal of impurities and unreacted substances. The mixture was then filtered and dried (continuously dried at 40°C for 24 h) to obtain the photochromic material. The amount of divinylbenzene used was 2 wt% of the sum of the mass of 4,4'-diaminoazobenzene and acrylic acid; the amount of phenyl peroxide used was 2 wt% of the azobenzene monomer. The color-changing layer is prepared by the following method: A solution casting method was used to dissolve photochromic material powder in an appropriate amount of ethanol (10 wt%), which was then coated onto a clean release film in a mold. The solvent was slowly evaporated at room temperature to obtain a color-changing layer with a thickness of 5-20 μm. Under 365 nm ultraviolet light irradiation, this color-changing layer rapidly changed from light to dark within 1-2 seconds; after the ultraviolet irradiation was stopped and the layer was exposed to visible light, it returned to a nearly transparent state within tens of seconds. The deformable layer was prepared by the following method: PLA was dissolved in carbon tetrachloride at a concentration of 10 wt% to ensure a homogeneous solution free of particulate matter. Then, epoxy acrylate (PLA to epoxy acrylate mass ratio of 10:1) was added under magnetic stirring and thoroughly mixed to obtain a mixed solution. The mixed solution was poured into a mold, and the solvent was completely evaporated using a solvent evaporation method. The mold was then dried at room temperature for 24 hours until the pre-formed film was completely dry. The dried pre-formed film was then heat-treated at 120°C for 1 hour to obtain a deformable layer with a thickness of 100–300 μm. Shape memory testing showed that when the deformable layer was heated to 60°C and bent into a predetermined shape under external force, and then cooled to 25°C to fix it, the film essentially returned to its initial flat state within 5 seconds when heated back to 60°C.

[0087] The composite thin film was prepared by the following method: like Figure 2 As shown, a color-changing layer with a triangular cross-section and a deformable layer with a triangular cross-section are hot-pressed at a mass ratio of 1:1 to obtain a composite film with a thickness of 0.2~0.4 mm. Hot-pressing at 90℃ and 0.5 MPa for 20 min ensures good adhesion between the two layers.

[0088] Preparation of insulated glass components: The composite film 20 is sandwiched between two pieces of tempered glass with the color-changing layer facing outward and the deformation layer facing inward, and then the insulated glass components are made by vacuum evacuation and high-temperature lamination.

[0089] Example 2 An application of a smart window system based on photochromic shape memory polymers: The system acquires environmental parameters of the window body; determines future weather changes based on these parameters; and, based on future weather changes, current environmental parameters, and user needs, determines control commands to control the opening and closing of the window body and the color-changing layer. Specifically, the control module mainly outputs two types of control commands: the first control command, used to drive the working mode of the azobenzene layer, determine whether to activate the auxiliary ultraviolet light module, adjust the position of the shading module, etc.; and the second control command, which drives the heating unit of the shape memory polymer, corresponding to the target opening and closing angle of the window sash.

[0090] Specifically, on sunny days, the intensity of sunlight increases and then decreases from morning to evening. During this process, the window body is initially closed. As the sunlight intensity increases and the temperature rises, the external sunlight first acts on the color-changing layer, causing it to change color. After absorbing the sunlight, the color-changing layer transfers heat to the deformation layer. With the help of this transferred heat and the increase in external temperature, the deformation layer and the self-driven intelligent component simultaneously reach the glass transition temperature and deform synchronously. At this time, the self-driven intelligent component drives the actuator to move, causing the window body to open. As dusk falls or the user needs to close the window, the heating module can again drive the self-driven intelligent component to deform and close the window. Furthermore, according to the second control command, the heating power and time of the heating module are adjusted so that the shape memory polymer reaches the set temperature and produces a predetermined bending deformation, thereby causing the window sash to rotate.

[0091] Meanwhile, by acquiring environmental parameters in real time, the system calculates the environmental change value per unit time within the current time period. This environmental change value includes changes in light intensity, outdoor temperature, and outdoor humidity. When it detects that the outdoor humidity is too high and the change in light intensity exceeds the corresponding preset change threshold and drops sharply, it determines that there will be weather changes in the future and issues a control command to close the windows.

[0092] In this embodiment of the invention, the color change of the system is driven solely by photons by the color-changing layer, and the shape change is driven by the phase change of the shape memory polymer. The control system consumes power only briefly during the judgment and heating stages, and relies on the shape memory of the material to maintain its state for the rest of the time, thus achieving steady-state operation without continuous power maintenance. It can operate with low energy consumption, which is significantly better than the continuously powered electrochromic / motor window opening scheme.

[0093] It should be noted that, Figure 1 and Figure 4 Only one self-driven intelligent component is shown in the figure, but the present invention is not limited to one self-driven intelligent component.

[0094] It is understood that the structures illustrated in the embodiments of the present invention do not constitute a specific limitation on a smart window system based on photochromic shape memory polymers. In other embodiments of the present invention, a smart window system based on photochromic shape memory polymers may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0095] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. The parts of the present invention not described in detail are techniques known to those skilled in the art.

Claims

1. A smart window system based on photochromic shape memory polymer, characterized in that, include: The window body, the functional layer on the glass of the window body, the actuator, the sensing module and the control module; The functional layer consists of a composite film and a self-driven intelligent component; the composite film includes an outward-facing color-changing layer made of a photochromic material and an inward-facing deformation layer made of a shape memory polymer, and the self-driven intelligent component is made of the shape memory polymer. The self-driven intelligent component is strip-shaped and located on one side of the composite film, parallel to the left and right frames of the window body; one end of the self-driven intelligent component is fixedly connected to the first frame of the window body, and the other end is connected to the actuator. The actuator is used to control the opening and closing of the window body; wherein, the self-driven intelligent component deforms when the glass transition temperature of the shape memory polymer is reached, and drives the actuator to move, so as to realize the opening and closing of the window body; The sensing module is used to acquire environmental parameters; the control module is connected to the sensing module; the control module is used to receive the environmental parameters and determine the weather changes at future times, so as to issue control commands to realize the opening and closing of the window based on the environmental parameters and the weather changes.

2. The intelligent window system according to claim 1, characterized in that, The photochromic material was prepared by the following method: Azobenzene monomer is dissolved in a first solvent, and then matrix monomer and crosslinking agent are added and mixed to obtain a mixed solution; an initiator is added to the mixed solution to initiate a polymerization reaction to obtain the photochromic material; preferably, the polymerization reaction temperature is 60~80℃ and the time is 4~6h. Preferably, the azobenzene monomer is 4,4'-diaminoazobenzene; the matrix monomer is acrylic acid or polymethacrylic acid; the crosslinking agent is divinylbenzene; and the initiator is phenyl peroxide. More preferably, the mass ratio of the azobenzene monomer to the matrix monomer is 1:(2~3). More preferably, the amount of the crosslinking agent is 1 wt% to 3 wt% of the sum of the mass of the azobenzene monomer and the matrix monomer; More preferably, the amount of the initiator is 1 wt% to 2 wt% of the amount of the azobenzene monomer.

3. The intelligent window system according to claim 1, characterized in that, The shape memory polymer is obtained by crosslinking polylactic acid and epoxy acrylate; Preferably, the amount of epoxy acrylate used is 1wt% to 10wt% of the amount of polylactic acid used; Preferably, the deformable layer is prepared by the following method: The polylactic acid is dissolved in a second solvent, and then epoxy acrylate is added and mixed to obtain a mixed solution. The mixed solution is poured into a mold, and after the second solvent evaporates, a pre-made film is obtained. The pre-made film is then heat-treated to complete cross-linking, and the deformable layer is obtained.

4. The intelligent window system according to claim 1, characterized in that, The composite film was prepared by the following method: (1) The photochromic material is formed into the color-changing layer by solution casting; wherein the cross-section of the color-changing layer is triangular or trapezoidal; (2) The color-changing layer and the deformation layer are hot-pressed at a mass ratio of 1:1 to obtain the composite film; wherein the cross-section of the color-changing layer is a triangle or trapezoid that matches the color-changing layer, so that the cross-section of the composite film is rectangular; and the content of shape memory polymer is different in different thickness directions; Preferably, the hot pressing is performed at 80~100℃ and 0.2~0.5MPa for 10~20min; More preferably, the thickness of the composite film is 0.2~0.4 mm.

5. The intelligent window system according to claim 1, characterized in that, The functional layer is located in the hollow area of ​​the hollow glass structure; And / or, When the window body is closed, the functional layer completely covers the glass; when the window body is open, the functional layer does not cover the glass; wherein, the composite film deforms synchronously with the self-driven intelligent component; preferably, the deformation layer is integrally formed with the self-driven intelligent component.

6. The intelligent window system according to claim 1, characterized in that, The functional layer includes at least one of the self-driven intelligent components; The self-driven intelligent component is located on one side adjacent to the window hinge, the first frame is the lower frame, and the actuator is hidden in the frame.

7. The intelligent window system according to any one of claims 1 to 6, characterized in that, It also includes a heating module, which is connected to the control module; The heating module receives control commands from the control module and heats the functional layer so that the self-driven intelligent component deforms when it reaches the glass transition temperature, thereby driving the actuator to open and close the window body; and / or, The sensing module includes at least one of a light sensor, a temperature sensor, and a humidity sensor; The light sensor is a photoresistor or a photodiode, which is installed on the top of the outer side of the window frame of the window body to obtain the light intensity. The temperature sensors are respectively installed on the outer surface of the window body and on the indoor side near the window body, and are used to obtain the indoor temperature and the outdoor temperature. The humidity sensor is installed outdoors to obtain outdoor humidity.

8. The intelligent window system according to claim 7, characterized in that, Also includes: Light-shielding module and ultraviolet light module; The control module is also used to send a shading command to the shading module when the light intensity exceeds the first preset light intensity threshold, so as to adjust the amount of light entering the room and control the degree of color change of the color-changing layer. And when the light intensity is lower than the second preset light intensity threshold, an illumination command is sent to the ultraviolet light module to restore the color-changing layer to its original color; The control module is also used to issue the control command to adjust the opening degree of the window body when the difference between the indoor temperature and the outdoor temperature exceeds a preset temperature threshold. The control module is also used to issue the control command to adjust the opening degree of the window body when the difference between the outdoor humidity and the indoor humidity exceeds a preset humidity threshold.

9. The intelligent window system according to claim 7 or 8, characterized in that, The control module is used to calculate the environmental change value per unit time based on the environmental parameters acquired in real time, and when the environmental change value exceeds a preset change threshold, it determines that there will be weather changes in the future, and then issues the control command to close the window body; wherein, the environmental parameters include light intensity, indoor temperature, outdoor temperature, and outdoor humidity; and / or, The control module is used to issue control commands based on the environmental parameters and a preset rule base; wherein, the preset rule base stores control commands for different environmental parameters.

10. An application based on the intelligent window system according to any one of claims 1 to 9, characterized in that, The application method includes: Obtain the environmental parameters of the window itself; Determine future weather changes based on the environmental parameters; Based on the weather changes at the future moment, current environmental parameters, and user needs, control commands are determined to control the opening and closing of the window body and the color change of the color-changing layer.

Images