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CN-122011496-A - Preparation method of polymer-based radiation refrigeration material with porous particle nested structure

CN122011496ACN 122011496 ACN122011496 ACN 122011496ACN-122011496-A

Abstract

The invention provides a preparation method of a polymer-based radiation refrigerating material with a porous particle nested structure, and belongs to the technical field of radiation cooling energy-saving structural materials. The preparation process includes the preparation of pre-emulsion with polymer matrix, diluent and emulsifier, preparation of water insoluble polymer polydimethylsiloxane, preparation of dispersion with nanometer particle and water, adding the dispersion into the pre-emulsion, stirring to obtain water-in-oil emulsion, and preparation of polymer base radiation refrigerating material with emulsion template process. The internal structure of the material provided by the invention consists of three photon scattering interfaces with refractive index gradients, including air/polymer, nano particles/polymer and air/nano particles, so that solar reflectivity of more than 93.0% and atmospheric window emissivity of more than 96.0% are realized. The material can realize the cooling of the temperature which is 5.0 ℃ lower than the ambient temperature in the daytime, the maximum radiation cooling power can reach 61.0W/m 2 , and the maximum radiation cooling power can reach 105.5/W m 2 when the material is cooled to 16.0 ℃ lower than the ambient temperature at night.

Inventors

  • ZHAO BIN
  • JIN CHENG
  • PEI GANG
  • NI JIAHAO

Assignees

  • 中国科学技术大学

Dates

Publication Date
20260512
Application Date
20260326

Claims (8)

  1. 1. A preparation method of a polymer-based radiation refrigeration material with a porous particle nested structure is characterized by comprising the following steps: (1) Mixing a polymer matrix, a diluent and an emulsifier PEG-10 polydimethylsiloxane according to a volume ratio of 1:0.5:0.01-0.03 to obtain a pre-emulsion; the polymer matrix is one of water-insoluble polymer Polydimethylsiloxane (PDMS), acrylic resin and polymethylpentene; the diluent is cyclohexane or ethyl acetate; (2) Ultrasonically dispersing the nano particles and water according to the mass ratio of 0.1:1 to obtain a dispersion liquid; the nano particles are one of nano silicon dioxide powder, nano aluminum oxide powder and nano zirconium oxide powder, and the particle size is 200 nm-700 nm; (3) Adding the dispersion liquid into the pre-emulsion according to the volume ratio of 1-3:1, and vigorously stirring to obtain white water-in-oil emulsion; (4) Degassing the water-in-oil emulsion in a vacuum environment; (5) Pouring the deaerated water-in-oil emulsion into a molding die, scraping and coating the film, covering and sealing the film by using a gas-impermeable material such as a glass cover plate or a metal sheet, compacting the film moderately, and heating and pre-curing the film to obtain a thin plate-shaped object; (6) Further heating and drying the thin plate-shaped object to completely remove the internal moisture to obtain the polymer-based radiation refrigeration material with the porous particle nested structure; The solar reflectance of the polymer-based radiation refrigeration material is greater than 93.0%, and the atmospheric window emissivity is greater than 96.0%; The temperature is 3.0-5.0 ℃ lower than the ambient temperature in the daytime, the radiation cooling power in the daytime is 45.0-61.0W/m 2 , the temperature is 12.0-16.0 ℃ lower than the ambient temperature in the night, and the radiation cooling power in the night is 100.0-105.5/W m 2 .
  2. 2. The preparation method of the polymer-based radiation refrigeration material with the porous particle nested structure, which is disclosed in claim 1, is characterized in that in the step (2), the ultrasonic dispersion power is 300W, and the dispersion time is 15-35 min.
  3. 3. The method of claim 1, wherein in step (3), the dispersion is added to the pre-emulsion at a rate of 30 ml/min.
  4. 4. The preparation method of the polymer-based radiation refrigeration material with the porous particle nested structure, which is disclosed in claim 1, is characterized in that in the step (3), the intense stirring condition is that the stirring speed is 1000-12000 r/min, and the time is 10-30 min.
  5. 5. The method for preparing the polymer-based radiation refrigeration material with the porous particle nested structure, which is disclosed in claim 1, is characterized in that in the step (4), the vacuum degassing condition is that the vacuum degree is 200Pa, and the time is 15min.
  6. 6. The preparation method of the polymer-based radiation refrigeration material with the porous particle nested structure, which is disclosed in claim 1, is characterized in that in the step (5), the heating pre-curing condition is that the temperature is 40-60 ℃ and the time is 3-4 hours.
  7. 7. The method of claim 1, wherein in the step (5), the thickness of the sheet is 1.0-2.0 mm.
  8. 8. The preparation method of the polymer-based radiation refrigeration material with the porous particle nested structure, which is disclosed in claim 1, is characterized in that in the step (6), the heating and drying conditions are that the temperature is 100-150 ℃ and the time is 30-70 min.

Description

Preparation method of polymer-based radiation refrigeration material with porous particle nested structure Technical Field The invention belongs to the technical field of radiation cooling materials, and particularly relates to a polymer-based radiation refrigerating material with a porous particle nested structure and a preparation method thereof. Background Under the urgent global demand of coping with high temperature and energy saving and carbon reduction, passive radiant refrigeration technology is attracting attention due to its zero energy consumption cooling potential. The ideal radiation refrigeration material needs to have both high emissivity in the atmospheric window band (8-13 microns) and high reflectivity in the solar spectrum band (0.3-2.5 microns). At present, a multilayer film structure based on precise coating or coating has excellent optical performance under laboratory conditions, but faces the problems of complex preparation process, high cost and the like, a particle blending composite material with high filler load (60 wt%) is easy to implement, but has optical efficiency reaching the bottleneck, meanwhile, the high filler load can cause the material to be fragile and the nano particles to be aggregated, and the traditional porous material depending on a toxic solvent or complex template removing process faces the environmental protection and scale bottleneck. Therefore, the current technology has the bottleneck that how to build up the multiple scattering system of the cooperation of the particles, the pores and the polymer matrix in the material by a green and scalable method, the structure not only can obviously improve the light scattering efficiency and the upper limit of the optical performance by the huge refractive index difference between the air/polymer and the particles, but also can radically avoid the dependence on the high filler content and the harmful process. Disclosure of Invention In order to solve the problems of high cost, toxic solvents and complex preparation method of the radiation refrigeration material in the prior art, the invention provides a polymer-based radiation refrigeration material with a porous particle nested structure, and simultaneously provides a preparation method of the polymer-based radiation refrigeration material with the porous particle nested structure. The preparation operation steps of the polymer-based radiation refrigeration material with the porous particle nested structure are as follows: (1) Mixing a polymer matrix, a diluent and an emulsifier PEG-10 polydimethylsiloxane according to a volume ratio of 1:0.5:0.01-0.03 to obtain a pre-emulsion; the polymer matrix is one of water-insoluble polymer Polydimethylsiloxane (PDMS), acrylic resin and polymethylpentene; the diluent is cyclohexane or ethyl acetate; (2) Ultrasonically dispersing the nano particles and water according to the mass ratio of 0.1:1 to obtain a dispersion liquid; the nano particles are one of nano silicon dioxide powder, nano aluminum oxide powder and nano zirconium oxide powder, and the particle size is 200 nm-700 nm; (3) Adding the dispersion liquid into the pre-emulsion according to the volume ratio of 1-3:1, and vigorously stirring to obtain white water-in-oil emulsion; (4) Degassing the water-in-oil emulsion in a vacuum environment; (5) Pouring the deaerated water-in-oil emulsion into a molding die, scraping and coating the film, covering and sealing the film by using a gas-impermeable material such as a glass cover plate or a metal sheet, compacting the film moderately, and heating and pre-curing the film to obtain a thin plate-shaped object; (6) Further heating and drying the thin plate-shaped object to completely remove the internal moisture to obtain the polymer-based radiation refrigeration material with the porous particle nested structure; The solar reflectance of the polymer-based radiation refrigeration material is greater than 93.0%, and the atmospheric window emissivity is greater than 96.0%; The temperature is 3.0-5.0 ℃ lower than the ambient temperature in the daytime, the radiation cooling power in the daytime is 45.0-61.0W/m 2, the temperature is 12.0-16.0 ℃ lower than the ambient temperature in the night, and the radiation cooling power in the night is 100.0-105.5/W m 2. The further technical scheme is as follows: In the step (2), the ultrasonic dispersion power is 300W, and the dispersion time is 15-35 min. In step (3), the dispersion was added to the pre-emulsion at a rate of 30 ml/min. In the step (3), the stirring speed is 1000-12000 r/min under the condition of intense stirring, and the time is 20-50 min. In the step (4), the vacuum degassing condition is that the vacuum degree is 200Pa and the time is 15min. In the step (5), the pre-curing condition is heated at the temperature of 40-60 ℃ for 3-4 hours. In the step (5), the thickness of the sheet is 1.0-2.0 mm. In the step (6), the heating and drying conditions are that the temperature is