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CN-119613784-B - Photonic crystal hydrogel-based thermochromic intelligent window material and preparation method and application thereof

CN119613784BCN 119613784 BCN119613784 BCN 119613784BCN-119613784-B

Abstract

The invention discloses a photonic crystal hydrogel-based thermochromic intelligent window material, a preparation method and application thereof, wherein the photonic crystal hydrogel-based thermochromic intelligent window material is obtained by filling a three-dimensional photonic crystal structure with a temperature-sensitive hydrogel prepolymer liquid and then curing the three-dimensional photonic crystal structure, the temperature-sensitive hydrogel prepolymer liquid is obtained by adding a temperature-sensitive monomer, modified cellulose and a crosslinking agent into deionized water, stirring the mixture under an ice bath condition until the mixture is completely dissolved after ultrasonic dispersion, adding an initiator and stirring the mixture until the mixture is dissolved, and adding N, N, N ', N' -tetramethyl ethylenediamine and stirring the mixture uniformly. The photonic crystal hydrogel-based thermochromic intelligent window material prepared by the invention can regulate and control the window transmittance in real time according to the ambient temperature, and has sensitive thermochromic effect and excellent infrared shielding performance.

Inventors

  • SHEN HUIFANG
  • LI CHUNHAO
  • Ke Aojue
  • ZHANG XINYA

Assignees

  • 华南理工大学

Dates

Publication Date
20260505
Application Date
20241127

Claims (8)

  1. 1. A photonic crystal hydrogel-based thermochromic intelligent window material is characterized in that a three-dimensional photonic crystal structure is filled with a temperature-sensitive hydrogel prepolymer liquid and then solidified, the temperature-sensitive hydrogel prepolymer liquid is obtained by adding a temperature-sensitive monomer, modified cellulose and a crosslinking agent into deionized water, stirring the mixture under an ice bath condition until the mixture is completely dissolved, then adding an initiator, stirring the mixture until the mixture is dissolved, adding N, N, N ', N' -tetramethyl ethylenediamine, stirring the mixture uniformly, wherein the temperature-sensitive monomer simultaneously has a hydrophilic group and a hydrophobic group, and the LCST is-5-70 ℃, the three-dimensional photonic crystal structure is obtained by coating a modified colloidal crystal obtained by adding transparent conductive oxide nanoparticle dispersion liquid into a colloidal crystal on a carrier through a doctor blade coating method or a spin coating method, and the colloidal crystal is obtained by pre-assembling the colloidal crystal on a pipe wall after centrifuging the colloidal particle dispersion liquid; The dosages of the temperature-sensitive monomer, the cross-linking agent and the initiator are respectively 7-15 wt%, 0.05-0.1 wt% and 0.2-0.3 wt% of the temperature-sensitive hydrogel prepolymer raw material, the mass ratio of the temperature-sensitive monomer to the modified cellulose is 10:1-40:1, the molar ratio of N, N' -tetramethyl ethylenediamine to the initiator is 2:1-1:1, and the mass ratio of the three-dimensional photonic crystal structure to the temperature-sensitive hydrogel prepolymer is 7-12:100; The transparent conductive oxide nano particles are one or more of indium tin oxide, tin antimony oxide and zinc aluminum oxide, and the modified cellulose is prepared by esterification or etherification of cellulose.
  2. 2. The photonic crystal hydrogel-based thermochromic smart window material of claim 1, wherein the temperature-sensitive monomer is one or more of N-isopropylacrylamide, N-t-butylacrylamide, N-diethylacrylamide, N-propylacrylamide, and N, N-dimethylacrylamide.
  3. 3. The photonic crystal hydrogel-based thermochromic smart window material of claim 1, wherein the modified cellulose is one or more of methylcellulose, carboxymethylcellulose, hydroxypropyl cellulose, and hydroxypropyl methylcellulose.
  4. 4. The photonic crystal hydrogel-based thermochromic intelligent window material according to claim 1, wherein the cross-linking agent is one or more of N, N' -methylenebisacrylamide, polyethylene glycol diacrylate and allyl methacrylate, the initiator is one or more of ammonium persulfate, potassium persulfate and sodium persulfate, the colloidal particle dispersion liquid is prepared by dispersing colloidal particle powder in deionized water, and the colloidal particles are polystyrene microspheres, polymethyl methacrylate microspheres, siO 2 microspheres or TiO 2 microspheres.
  5. 5. The photonic crystal hydrogel-based thermochromic intelligent window material according to claim 4, wherein the colloidal particles account for 20-30wt% of the dispersion liquid, and the particle size of the colloidal particles is 160-280 nm.
  6. 6. The photonic crystal hydrogel-based thermochromic intelligent window material according to claim 1 is characterized in that the curing temperature is 4-15 ℃, the curing time is 12-24 hours, the stirring is carried out under ice bath conditions until the photonic crystal hydrogel-based thermochromic intelligent window material is completely dissolved, an initiator is added, the stirring is carried out until the photonic crystal hydrogel-based thermochromic intelligent window material is dissolved, the stirring involved in the stirring of N, N, N ', N' -tetramethyl ethylenediamine is carried out is magnetic stirring uniformly, the stirring speed is 500-1000 rpm, the stirring time of adding N, N, N ', N' -tetramethyl ethylenediamine is 30-60 seconds, the ultrasonic dispersion time is 60-120 minutes, the centrifugal speed is 4000-8000 rpm, the centrifugal time is 40-60 minutes, and the carrier is glass.
  7. 7. The method for preparing the photonic crystal hydrogel-based thermochromic intelligent window material according to any one of claims 1 to 6, which is characterized by comprising the following steps: (1) Centrifuging the colloidal particle dispersion liquid until the wall of the centrifuge tube is preassembled to form hierarchical light spots with different colors, thereby obtaining colloidal crystals; (2) Adding transparent conductive oxide nano particles into the colloidal crystal in the step (1), and performing ultrasonic dispersion to obtain a modified colloidal crystal; (3) The modified colloidal crystal is self-assembled on a carrier through blade coating or spin coating to form a periodic ordered three-dimensional photonic crystal structure; (4) Adding a temperature-sensitive monomer, modified cellulose and a crosslinking agent into deionized water, stirring under ice bath condition after ultrasonic dispersion until the monomer is completely dissolved, adding an initiator, stirring until the monomer is dissolved, adding a catalyst N, N, N ', N' -tetramethyl ethylenediamine, and stirring uniformly to obtain a temperature-sensitive hydrogel prepolymer; (5) Filling the temperature-sensitive hydrogel prepolymer liquid in the step (4) on the carrier in the step (3) to obtain a three-dimensional photonic crystal structure through self-assembly, and then curing to obtain the photonic crystal hydrogel-based thermochromic intelligent window material.
  8. 8. Use of the photonic crystal hydrogel-based thermochromic smart window material of any of claims 1-6 in the preparation of a smart window.

Description

Photonic crystal hydrogel-based thermochromic intelligent window material and preparation method and application thereof Technical Field The invention relates to a thermochromic material, in particular to a photonic crystal hydrogel-based thermochromic intelligent window material and a preparation method and application thereof, and belongs to the technical field of intelligent heat insulation windows. Background Of the total energy consumption worldwide, building energy consumption is about 36%, with heating, ventilation and air conditioning (HVAC) systems accounting for about 40-50% of building energy consumption. The windows of the building can influence the heating, cooling and lighting of the interior of the house, and optimizing the windows is a non-negligible step in reducing the energy consumption of the building. In order to improve energy efficiency and living comfort, studies on smart windows have received much attention. The intelligent window can regulate and control the transmittance of the window according to illumination intensity, ambient temperature and the like, control the indoor temperature to be kept within a comfortable range of a human body, and reduce the energy consumption of an HVAC system. At present, more intelligent windows are researched, wherein the intelligent windows comprise electrochromic windows and thermochromic windows, the electrochromic windows accurately regulate the transmittance of the windows and the colors of the windows through regulating voltages, but the electrochromic windows are actively regulated and controlled, manual control is needed, the electrochromic windows need to be powered, so that the energy consumption is further increased, the thermochromic windows are passively regulated and controlled, the transmittance of the windows can be adaptively regulated according to the ambient temperature, and the effect of color change can be achieved without additional energy supply. Chinese patent No. CN 116284850B provides a method for preparing ionic hydrogel electrolyte and uses it in electrochromic intelligent window. The method comprises the steps of mixing lithium chloride with acrylamide to prepare a deep eutectic solvent, adding the deep eutectic solvent into hydrogel precursor liquid containing N-isopropylamide, sodium dodecyl sulfate and di-tert-butyl peroxyisopropyl benzene, filling the hydrogel precursor liquid into a hollow glass interlayer formed by conductive glass containing a WO 3 film, and curing to obtain the electrochromic intelligent window. However, the technology needs additional power supply to realize the color-changing effect of the window, and electrochromic is realized only by means of hydrogel, so that the solar light modulation capability of the intelligent window is poor, and meanwhile, the energy consumption of the electrochromic window is higher. Chinese patent CN 114573756B discloses a method for preparing thermosensitive gel for thermochromic intelligent window. The technology uses hydroxypropyl methyl cellulose to modify N-isopropyl acrylamide, and obtains poly N-isopropyl acrylamide/hydroxypropyl methyl cellulose thermosensitive composite gel through redox initiation free radical polymerization at low temperature. Although the phase transition temperature of the hydrogel is close to room temperature and the thermochromic is energy-saving, the thermochromic prepared from the temperature-sensitive monomer such as N-isopropyl acrylamide can only be changed from a transparent state to a white opaque state. In addition, the thermochromic window cannot reach the phase transition temperature of the temperature-sensitive monomer due to lower temperature in winter, so that the hydrogel cannot undergo phase transition, the indoor illumination intensity is too strong, and the living comfort in winter is greatly reduced. Chinese patent application CN 104129121A discloses thermochromic windows, the solar light transmittance of which can be adjusted according to temperature. The thermochromic window includes a flexible substrate, a thermochromic film disposed on the flexible substrate, and a thermally processed substrate bonded to the thermochromic film. The thermochromic material is composed of one selected from the group consisting of vanadium dioxide (VO 2), titanium (III) oxide (Ti 2O3), niobium dioxide (NbO 2) and nickel sulfide (NiS). The phase transition temperature of the thermochromic material is controlled by doping the thermochromic material with a dopant. The phase transition temperature of the thermochromic material in the technology is reduced along with the increase of the doping proportion of the doping agent, but the thermochromic material is metal oxide, the doping agent selected from Mo, W, nb, ta, fe, al, ti, sn and Ni is also metal, the overall color change temperature is higher, and the low-temperature color change is difficult to control. And the inherent yellow brown color of the VO 2 preferred by the technology ser