Phase-change temperature-control polyurethane material and preparation method thereof

Abstract

The invention discloses a phase-change temperature-control polyurethane material and a preparation method thereof, and relates to the technical field of polymer materials. When preparing the phase-change temperature-control polyurethane material, the present invention reacts vanadium dioxide and 4-anilinotriethoxysilane to obtain pre-modified vanadium dioxide; pre-modified vanadium dioxide and N,N-dimethyl-4-nitrosoaniline are reacted to obtain modified vanadium dioxide; phenylboric acid and 3-chloropropylmethyldimethoxysilane are polymerized and end-capped with 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane to obtain borosiloxane oligomer; borosiloxane oligomer, 1,6-hexanediol and isophorone diisocyanate are polymerized to obtain functionalized polyurethane; functionalized polyurethane and modified vanadium dioxide are uniformly mixed, and compression molding is performed to obtain the phase-change temperature-control polyurethane material. The phase-change temperature-control polyurethane material prepared by the present invention has excellent energy-saving temperature control, anti-aging, antibacterial, self-healing and mechanical properties.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, in particular to a phase-change temperature-control polyurethane material and a preparation method thereof. Background Art

[0002] In recent years, with the development of industry and population growth, energy consumption has also increased rapidly worldwide. It is reported that buildings in developed countries account for approximately 40% of total energy consumption, exceeding that of industry and transportation. Over half of this energy consumption is used for heating, ventilation, and air conditioning. Reducing energy consumption and improving energy efficiency are becoming increasingly important. Windows are considered the least energy-efficient part of a building because they transfer heat from the outside in, contrary to the need to dissipate heat outdoors. Smart windows dynamically and reversibly respond to external stimuli to regulate the intensity and energy of sunlight entering a room. Compared to ordinary glass windows, smart windows not only ensure indoor lighting but also, under certain conditions, regulate the impact of sunlight on indoor temperature, providing a viable solution for building energy conservation.

[0003] Polyurethane, the polymer material used in the production of doors and windows, can age over time due to exposure to wind, sun, and rain, shortening the window's service life. Therefore, it is necessary to develop a phase-change temperature-control polyurethane material with excellent anti-aging properties that can achieve energy savings and temperature control while extending the material's service life. Summary of the Invention

[0004] The object of the present invention is to provide a phase-change temperature-control polyurethane material and a preparation method thereof, so as to solve the problems existing in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A phase-change temperature-control polyurethane material is prepared by reacting pre-modified vanadium dioxide and N,N-dimethyl-4-nitrosoaniline to obtain modified vanadium dioxide; polymerizing borosiloxane oligomer, 1,6-hexanediol, and isophorone diisocyanate to obtain functionalized polyurethane; and uniformly mixing the functionalized polyurethane and modified vanadium dioxide, followed by compression molding.

[0007] The pre-modified vanadium dioxide is prepared by reacting vanadium dioxide and 4-anilinotriethoxysilane;

[0008] The borosiloxane oligomer is prepared by polymerizing phenylboronic acid and 3-chloropropylmethyldimethoxysilane and capping the polymer with 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane.

[0009] As an optimization, the preparation method of the phase-change temperature-control polyurethane material includes the following preparation steps:

[0010] (1) Pre-modified vanadium dioxide, glacial acetic acid, and N,N-dimethylformamide were mixed uniformly in a mass ratio of 1:(0.6~0.8):(40~50), and ultrasonically dispersed for 20~30 min. N,N-dimethyl-4-nitrosoaniline (3~4 times the mass of the pre-modified vanadium dioxide) was added, and stirred at 50~54°C and 200~300 r / min for 4~5 h. The mixture was filtered, washed with anhydrous ethanol and deionized water for 3~5 times each, and dried at 70~80°C under vacuum conditions for 9~10 h to obtain modified vanadium dioxide.

[0011] (2) Phenylboric acid and 3-chloropropylmethyldimethoxysilane were added to 1,4-dioxane (14-16 times the mass of phenylboric acid) in a molar ratio of 1:(1.2-1.3), stirred at 79-81°C and 200-300 r / min for 50-60 min, and a capping agent (0.11-0.13 times the mass of 3-chloropropylmethyldimethoxysilane) was added, and the stirring reaction was continued for 8-10 min. The mixture was cooled to room temperature, washed with a mixture of equal volumes of toluene and deionized water, and allowed to stand for stratification. The organic phase was taken and dried at 50-60°C under vacuum conditions for 8-10 h to obtain borosiloxane oligomers.

[0012] (3) The borosiloxane oligomer, 1,6-hexanediol, dibutyltin dilaurate and butanone were mixed evenly, stirred at 10-30°C and 100-200 r / min for 10-12 minutes, heated to 76-78°C, and 2-2.2 times the mass of isophorone diisocyanate of the borosiloxane oligomer was added, and the reaction was continued with stirring for 4-5 hours. Anhydrous ethanol was added at 1-1.2 times the mass of isophorone diisocyanate and mixed evenly, and the mixture was continued with stirring for 5-7 minutes. The mixture was dried at 68-70°C under vacuum conditions for 10-12 hours to obtain a functionalized polyurethane.

[0013] (4) Functionalized polyurethane and modified vanadium dioxide were added into an internal mixer at a mass ratio of 1:(0.03~0.05), stirred at 180~190℃ and 60~80r / min for 6~8min, placed in a molding machine for compression molding, and demolded after cooling to room temperature to obtain a phase change temperature-controlled polyurethane material.

[0014] As an optimization, the preparation method of the pre-modified vanadium dioxide in step (1) is as follows: vanadium dioxide and anhydrous ethanol are uniformly mixed in a mass ratio of 1:(60~70), ultrasonically dispersed for 1.2~1.4h, aniline silane hydrolyzate of 7~8 times the mass of vanadium dioxide is added, stirred at 50~60℃ and 100~200r / min for 2~2.2h, filtered, washed with anhydrous ethanol 3~5 times, and dried at 60~70℃ under vacuum conditions for 9~10h to obtain pre-modified vanadium dioxide.

[0015] As an optimization, the particle size of the vanadium dioxide is 2000 mesh, and the manufacturer is Qinghe County Chaotai Metal Materials Co., Ltd.

[0016] As an optimization, the preparation method of the aniline silane hydrolyzate is: 4-anilinotriethoxysilane and deionized water are mixed uniformly in a mass ratio of 1:(20~22), stirred at 10~30°C and 100~200r / min for 10~12min, adjusted to pH 5.6~5.8 with oxalic acid aqueous solution, and continued stirring for 20~30min to prepare the aniline silane hydrolyzate.

[0017] As an optimization, the concentration of the oxalic acid aqueous solution is 1 mol / L.

[0018] As an optimization, the capping agent in step (2) is: 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane.

[0019] As an optimization, the mass ratio of the borosiloxane oligomer, 1,6-hexanediol, dibutyltin dilaurate, and butanone in step (3) is 1:(0.2~0.3):(0.03~0.05):(8~10).

[0020] As an optimization, the process parameters of the compression molding in step (4) are as follows: setting the temperature of the upper and lower mold plates of the molding machine to 200-210°C, the pressure to 14-16 MPa, and the time to 7-9 minutes.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] In the preparation of the phase-change temperature-control polyurethane material, the present invention comprises the following steps: reacting vanadium dioxide and 4-anilinotriethoxysilane to obtain pre-modified vanadium dioxide; reacting the pre-modified vanadium dioxide and N,N-dimethyl-4-nitrosoaniline to obtain modified vanadium dioxide; polymerizing phenylboric acid and 3-chloropropylmethyldimethoxysilane, and capping with 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane to obtain borosiloxane oligomer; polymerizing the borosiloxane oligomer, 1,6-hexanediol and isophorone diisocyanate to obtain functionalized polyurethane; and uniformly mixing the functionalized polyurethane and the modified vanadium dioxide, followed by compression molding to obtain the phase-change temperature-control polyurethane material.

[0023] First, vanadium dioxide and 4-anilinotriethoxysilane are reacted to prepare pre-modified vanadium dioxide, and aniline groups are introduced on the surface of the pre-modified vanadium dioxide; the aniline groups introduced on the surface of the pre-modified vanadium dioxide undergo a Mills reaction with the nitroso groups on N,N-dimethyl-4-nitrosoaniline to prepare modified vanadium dioxide, an azobenzene structure is generated on the surface of the modified vanadium dioxide, and a tertiary amine structure is introduced. The azobenzene structure will transform from a trans conformation to a cis conformation under the action of ultraviolet light, and the tertiary amine structure will be transformed from a trans conformation to a cis conformation under the action of ultraviolet light. When exposed to light, it will transform from cis conformation to trans conformation. This reversible conformational change can absorb ultraviolet light, giving the phase-change temperature-control polyurethane material excellent anti-aging properties. The tertiary amine structure introduced on the surface of the modified vanadium dioxide can react with the chlorine atoms introduced on the side chain of the functionalized polyurethane molecule to form a quaternary ammonium salt structure, forming a cross-linked structure between the polyurethane molecular chain and the modified vanadium dioxide, inhibiting the relative slip between the polyurethane molecular chains and improving the mechanical properties of the phase-change temperature-control polyurethane material. At the same time, the generated quaternary ammonium salt structure has It has an antibacterial effect and can give phase-change temperature-control polyurethane materials excellent antibacterial properties; vanadium dioxide is a thermochromic material that undergoes a reversible phase change at 68°C, transforming from an insulating monoclinic phase to a metallic rutile phase. At the same time, the optical and electrical properties change dramatically, and the infrared transmittance changes from high transmittance at low temperatures to high reflectivity at high temperatures, showing excellent infrared region regulation capabilities. When glass windows are produced with phase-change temperature-control polyurethane materials, the requirements of indoor warmth in winter and coolness in summer can be achieved, greatly reducing the energy consumption caused by indoor heating in winter and cooling in summer; and the visible light transmittance of vanadium dioxide remains basically unchanged during the phase change process, and still maintains a high visible light transmittance, which can provide sufficient lighting for buildings; vanadium dioxide is an inorganic material and has poor compatibility with organic polymer material polyurethane. Direct addition will result in uneven distribution and agglomeration of vanadium dioxide. Surface modification of vanadium dioxide is performed to improve the compatibility of vanadium dioxide with polyurethane, so that vanadium dioxide is evenly dispersed in polyurethane, and the phase-change temperature-control effect of vanadium dioxide is fully exerted.

[0024] Secondly, phenylboronic acid and 3-chloropropylmethyldimethoxysilane are polymerized and end-capped with 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane to prepare a borosiloxane oligomer, and a Si-OB structure is introduced into the main chain of the borosiloxane oligomer molecule, a chlorine atom is introduced into the side chain of the borosiloxane oligomer molecule, and a hydroxyl group is introduced into both ends of the borosiloxane oligomer molecular chain; the hydroxyl groups introduced into both ends of the borosiloxane oligomer molecular chain enable it to participate in the polymerization reaction of polyurethane; the borosiloxane oligomer, 1,6-hexanediol and isophorone diisocyanate are polymerized to prepare a functionalized polyurethane; the Si-OB structure is introduced into the main chain of the functionalized polyurethane molecule, and the hydroxyl groups introduced into the side chain of the borosiloxane oligomer molecule are Chlorine atoms are introduced into the side chains of functionalized polyurethane molecules; boron atoms of Si-OB in the main chain can form boron-oxygen coordination bonds with oxygen atoms in adjacent molecular chains. The boron-oxygen coordination bond is a dynamic reversible bond. The boron atom with a vacancy acts as an acceptor of the lone electron pair of the oxygen atom in the adjacent molecular chain, forming a non-bonded complex between molecules. The interaction between the boron and oxygen atoms causes dynamic physical cross-linking between the molecular chains. The bonding action is in a dynamic process of continuous dissociation and re-formation, thereby making the phase-change temperature-control polyurethane material have self-healing properties; the formation of boron-oxygen coordination bonds also causes physical cross-linking between polyurethane molecular chains, further improving the mechanical properties of the phase-change temperature-control polyurethane material. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention. Example 1

[0026] A method for preparing a phase-change temperature-controlling polyurethane material, comprising the following steps:

[0027] (1) 4-anilinotriethoxysilane and deionized water were mixed in a mass ratio of 1:20, stirred at 10°C and 100 r / min for 12 min, and the pH was adjusted to 5.6 with a 1 mol / L oxalic acid aqueous solution. The mixture was stirred for 30 min to prepare an anilinosilane hydrolyzate. Vanadium dioxide and anhydrous ethanol were mixed in a mass ratio of 1:60, ultrasonically dispersed for 1.2 h, and an anilinosilane hydrolyzate 7 times the mass of vanadium dioxide was added. The mixture was stirred at 50°C and 100 r / min for 2.2 h, filtered, and The pre-modified vanadium dioxide was prepared by washing with anhydrous ethanol three times and drying at 60°C for 10 hours under vacuum conditions. The pre-modified vanadium dioxide, glacial acetic acid, and N,N-dimethylformamide were mixed uniformly in a mass ratio of 1:0.6:40, and ultrasonically dispersed for 20 minutes. N,N-dimethyl-4-nitrosoaniline (3 times the mass of the pre-modified vanadium dioxide) was added, and the mixture was stirred at 50°C and 200 r / min for 5 hours. The mixture was filtered, washed with anhydrous ethanol and deionized water three times each, and dried at 70°C for 10 hours under vacuum conditions to obtain modified vanadium dioxide.

[0028] (2) Phenylboric acid and 3-chloropropylmethyldimethoxysilane were added to 1,4-dioxane (14 times the mass of phenylboric acid) in a molar ratio of 1:1.2, and the mixture was stirred at 79°C and 200 r / min for 50 min. 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane (0.11 times the mass of 3-chloropropylmethyldimethoxysilane) was added and the mixture was stirred for 10 min. The mixture was cooled to room temperature and washed with an equal volume of toluene and deionized water. The mixture was allowed to stand for separation and the organic phase was taken and dried at 50°C for 10 h under vacuum to obtain borosiloxane oligomer.

[0029] (3) The borosiloxane oligomer, 1,6-hexanediol, dibutyltin dilaurate, and butanone were mixed in a mass ratio of 1:0.2:0.03:8, stirred at 10°C and 100 r / min for 12 minutes, heated to 76°C, and isophorone diisocyanate (2 times the mass of the borosiloxane oligomer) was added. The reaction was continued with stirring for 5 hours. Anhydrous ethanol (1 times the mass of the isophorone diisocyanate) was added and mixed evenly. The mixture was continued with stirring for 7 minutes. The mixture was dried at 68°C under vacuum for 12 hours to obtain a functionalized polyurethane.

[0030] (4) Functionalized polyurethane and modified vanadium dioxide were added into an internal mixer at a mass ratio of 1:0.03, stirred at 180°C and 60 r / min for 8 min, and placed in a molding machine for compression molding. The upper and lower mold plate temperatures of the molding machine were set to 200°C, the pressure was set to 14 MPa, and the time was set to 9 min. After cooling to room temperature, the mold was demolded to obtain a phase change temperature-controlled polyurethane material. Example 2

[0031] A method for preparing a phase-change temperature-controlling polyurethane material, comprising the following steps:

[0032] (1) 4-anilinotriethoxysilane and deionized water were mixed in a mass ratio of 1:21, stirred at 20°C and 150 r / min for 11 min, adjusted to pH 5.7 with 1 mol / L oxalic acid aqueous solution, and continued to stir for 25 min to prepare an anilinosilane hydrolyzate; vanadium dioxide and anhydrous ethanol were mixed in a mass ratio of 1:65, ultrasonically dispersed for 1.3 h, and an anilinosilane hydrolyzate 7.5 times the mass of vanadium dioxide was added, stirred at 55°C and 150 r / min for 2.1 h, filtered, and washed with anhydrous ethanol. The product was washed with water and ethanol four times and dried at 65°C for 9.5 hours under vacuum conditions to obtain pre-modified vanadium dioxide. The pre-modified vanadium dioxide, glacial acetic acid, and N,N-dimethylformamide were mixed uniformly in a mass ratio of 1:0.7:45, and ultrasonically dispersed for 25 minutes. N,N-dimethyl-4-nitrosoaniline (3.5 times the mass of the pre-modified vanadium dioxide) was added, and the mixture was stirred at 52°C and 250 r / min for 4.5 hours. The product was filtered, washed with anhydrous ethanol and deionized water four times each, and dried at 75°C for 9.5 hours under vacuum conditions to obtain modified vanadium dioxide.

[0033] (2) Phenylboric acid and 3-chloropropylmethyldimethoxysilane were added to 1,4-dioxane (15 times the mass of phenylboric acid) in a molar ratio of 1:1.25, and stirred at 80°C and 250 r / min for 55 min. 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane (0.12 times the mass of 3-chloropropylmethyldimethoxysilane) was added, and the stirring reaction was continued for 9 min. The mixture was cooled to room temperature, washed with a mixture of equal volumes of toluene and deionized water, and allowed to stand for stratification. The organic phase was taken and dried at 55°C under vacuum for 9 h to obtain borosiloxane oligomer.

[0034] (3) The borosiloxane oligomer, 1,6-hexanediol, dibutyltin dilaurate, and butanone were mixed in a mass ratio of 1:0.25:0.04:9, stirred at 20°C and 150 r / min for 11 minutes, heated to 77°C, and 2.1 times the mass of isophorone diisocyanate of the borosiloxane oligomer was added. The reaction was continued with stirring for 4.5 hours. Anhydrous ethanol was added in an amount of 1.1 times the mass of isophorone diisocyanate and mixed evenly. The mixture was continued with stirring for 6 minutes. The mixture was dried at 69°C under vacuum for 11 hours to obtain a functionalized polyurethane.

[0035] (4) Functionalized polyurethane and modified vanadium dioxide were added into an internal mixer at a mass ratio of 1:0.04, stirred at 185°C and 70 r / min for 7 min, and placed in a molding machine for compression molding. The upper and lower mold plate temperatures of the molding machine were set to 205°C, the pressure was 15 MPa, and the time was 8 min. After cooling to room temperature, the mold was demolded to obtain a phase change temperature-controlled polyurethane material. Example 3

[0036] A method for preparing a phase-change temperature-controlling polyurethane material, comprising the following steps:

[0037] (1) 4-anilinotriethoxysilane and deionized water were mixed in a mass ratio of 1:22, stirred at 30°C and 200 r / min for 10 min, and the pH was adjusted to 5.8 with a 1 mol / L oxalic acid aqueous solution, and stirred for 30 min to prepare an anilinosilane hydrolyzate; vanadium dioxide and anhydrous ethanol were mixed in a mass ratio of 1:70, ultrasonically dispersed for 1.4 h, and anilinosilane hydrolyzate 8 times the mass of vanadium dioxide was added, stirred at 60°C and 200 r / min for 2 h, filtered, and The pre-modified vanadium dioxide was prepared by washing with anhydrous ethanol five times and drying at 70°C for 9 hours under vacuum conditions. The pre-modified vanadium dioxide, glacial acetic acid, and N,N-dimethylformamide were mixed uniformly in a mass ratio of 1:0.8:50, and ultrasonically dispersed for 30 minutes. N,N-dimethyl-4-nitrosoaniline (4 times the mass of the pre-modified vanadium dioxide) was added, and the mixture was stirred at 54°C and 300 r / min for 4 hours. The mixture was filtered, washed with anhydrous ethanol and deionized water five times each, and dried at 80°C for 9 hours under vacuum conditions to obtain modified vanadium dioxide.

[0038] (2) Phenylboric acid and 3-chloropropylmethyldimethoxysilane were added to 1,4-dioxane (16 times the mass of phenylboric acid) in a molar ratio of 1:1.3, and the mixture was stirred at 81°C and 300 r / min for 50 min. 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane (0.13 times the mass of 3-chloropropylmethyldimethoxysilane) was added and the mixture was stirred for 8 min. The mixture was cooled to room temperature and washed with a mixture of equal volumes of toluene and deionized water. The mixture was allowed to stand for separation and the organic phase was taken and dried at 60°C under vacuum for 8 h to obtain borosiloxane oligomer.

[0039] (3) The borosiloxane oligomer, 1,6-hexanediol, dibutyltin dilaurate, and butanone were mixed in a mass ratio of 1:0.3:0.05:10, stirred at 30°C and 200 r / min for 10 minutes, heated to 78°C, and 2.2 times the mass of isophorone diisocyanate of the borosiloxane oligomer was added. The reaction was continued with stirring for 4 hours. Anhydrous ethanol was added in an amount of 1.2 times the mass of isophorone diisocyanate and mixed evenly. The mixture was continued with stirring for 5 minutes. The mixture was dried at 70°C under vacuum for 10 hours to obtain a functionalized polyurethane.

[0040] (4) Functionalized polyurethane and modified vanadium dioxide were added into an internal mixer at a mass ratio of 1:0.05, stirred at 190°C and 80 r / min for 6 min, and placed in a molding machine for compression molding. The upper and lower mold plate temperatures of the molding machine were set to 210°C, the pressure was 16 MPa, and the time was 7 min. After cooling to room temperature, the mold was demolded to obtain a phase change temperature-controlled polyurethane material.

[0041] Comparative Example 1:

[0042] The preparation method of the phase-change temperature-control polyurethane material of Comparative Example 1 differs from that of Example 2 in that step (1) is omitted and step (4) is modified as follows: functionalized polyurethane and vanadium dioxide are added to an internal mixer at a mass ratio of 1:0.04, stirred at 185°C and 70 rpm for 7 minutes, and then placed in a molding machine for compression molding. The upper and lower mold plates of the molding machine are set to a temperature of 205°C, a pressure of 15 MPa, and a molding time of 8 minutes. After cooling to room temperature, the material is demoulded to obtain a phase-change temperature-control polyurethane material. The remaining steps are the same as those of Example 2.

[0043] Comparative Example 2:

[0044] The preparation method of the phase-change temperature-control polyurethane material of Comparative Example 2 differs from that of Example 2 in that step (2) is different. Step (2) is modified as follows: phenylboric acid and dimethyldimethoxysilane are added in a molar ratio of 1:1.25 to 1,4-dioxane (15 times the mass of phenylboric acid), stirred at 80°C and 250 r / min for 55 minutes, 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane (0.12 times the mass of dimethyldimethoxysilane) is added, and the stirring reaction is continued for 9 minutes. The mixture is cooled to room temperature, washed with a mixture of equal volumes of toluene and deionized water, allowed to stand for stratification, and the organic phase is taken and dried at 55°C under vacuum for 9 hours to obtain a borosiloxane oligomer. The remaining steps are the same as those of Example 2.

[0045] Comparative Example 3:

[0046] The preparation method of the phase-change temperature-control polyurethane material of Comparative Example 3 differs from that of Example 2 only in that step (2) is omitted and step (3) is modified as follows: dihydroxy-terminated polysiloxane, 1,6-hexanediol, dibutyltin dilaurate, and butanone are uniformly mixed in a mass ratio of 1:0.25:0.04:9, stirred at 20°C and 150 r / min for 11 minutes, heated to 77°C, and isophorone diisocyanate (2.1 times the mass of the dihydroxy-terminated polysiloxane) is added. The reaction is continued with stirring for 4.5 hours, and anhydrous ethanol (1.1 times the mass of the isophorone diisocyanate) is added and mixed uniformly. The mixture is continued with stirring for 6 minutes, and dried at 69°C under vacuum for 11 hours to obtain a functionalized polyurethane; the molecular weight of the dihydroxy-terminated polysiloxane is 2000. The remaining steps are the same as those of Example 2.

[0047] Test Example 1

[0048] Energy-saving and temperature control performance test

[0049] Test method: The infrared blocking rate of the examples and comparative examples was tested at 20° C. and 90° C. using a solar film tester produced by Shenzhen Linshang Technology Co., Ltd. The results are shown in Table 1.

[0050] Table 1

[0051]

[0052] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 1, it can be found that the phase-change temperature-control polyurethane material prepared in the present invention has good energy-saving and temperature-control performance.

[0053] By comparison, the infrared blocking rates of Examples 1 to 3 at 20°C are lower than that of Comparative Example 1 at 20°C, and the infrared blocking rates of Examples 1 to 3 at 90°C are higher than that of Comparative Example 1 at 90°C, indicating that modified vanadium dioxide is prepared by reacting vanadium dioxide with 4-anilinotriethoxysilane and N,N-dimethyl-4-nitrosoaniline in sequence; vanadium dioxide is a thermochromic material that undergoes a reversible phase transition at 68°C from an insulating monoclinic phase to a metallic rutile phase, and simultaneously, the optical and electrical properties undergo a sharp change, and the infrared transmittance changes from high transmittance at low temperature to high transmittance at low temperature. The reflectivity is converted into high reflectivity at high temperature, showing excellent infrared region regulation ability. When glass windows are produced with phase-change temperature-control polyurethane materials, the indoor temperature can be kept warm in winter and cool in summer, greatly reducing the energy consumption caused by indoor heating in winter and cooling in summer. Vanadium dioxide is an inorganic material and has poor compatibility with organic polymer material polyurethane. Direct addition will result in uneven distribution and agglomeration of vanadium dioxide. Surface modification of vanadium dioxide is performed to improve the compatibility between vanadium dioxide and polyurethane, so that vanadium dioxide is evenly dispersed in polyurethane, giving full play to the phase-change temperature-control effect of vanadium dioxide.

[0054] Test Example 2

[0055] Testing of mechanical properties and anti-aging properties

[0056] Test method: According to GB / T1040, the examples and comparative examples were prepared into standard specimens, and their tensile strength M was tested. The standard specimens were irradiated with a xenon arc lamp for 14 days, and their tensile strength N was tested. The change rate of the tensile strength of the examples and comparative examples before and after UV aging was calculated: tensile strength change rate = (MN) / M×100%. The results are shown in Table 2

[0057] Table 2

[0058]

[0059] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 2, it can be found that the phase-change temperature-control polyurethane material prepared in the present invention has good mechanical properties and anti-aging properties.

[0060] By comparison, the tensile strength of Examples 1 to 3 is greater than that of Comparative Example 1, indicating that the aniline group introduced on the surface of the pre-modified vanadium dioxide undergoes a Mills reaction with the nitroso group on N,N-dimethyl-4-nitrosoaniline to produce modified vanadium dioxide, and a tertiary amine structure is introduced on the surface of the modified vanadium dioxide. The tertiary amine structure introduced on the surface of the modified vanadium dioxide can react with the chlorine atom introduced on the side chain of the functionalized polyurethane molecule to form a quaternary ammonium salt structure, forming a cross-linked structure between the polyurethane molecular chain and the modified vanadium dioxide, thereby inhibiting the relative slip between the polyurethane molecular chains and improving the mechanical properties of the phase change temperature-control polyurethane material.

[0061] By comparison, the tensile strength of Examples 1 to 3 is greater than that of Comparative Examples 2 to 3, indicating that phenylboric acid and 3-chloropropylmethyldimethoxysilane are polymerized and end-capped with 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane to prepare a borosiloxane oligomer, an Si-OB structure is introduced into the main chain of the borosiloxane oligomer molecule, a chlorine atom is introduced into the side chain of the borosiloxane oligomer molecule, and a hydroxyl group is introduced at both ends of the borosiloxane oligomer molecular chain; the hydroxyl groups introduced at both ends of the borosiloxane oligomer molecular chain enable it to participate in the polymerization reaction of the polyurethane; the borosiloxane oligomer, 1,6-hexanediol and isophorone diisocyanate are reacted to form a polyurethane copolymer; Functionalized polyurethane is prepared by polymerization of acid esters; Si-OB structure is introduced into the main chain of the functionalized polyurethane molecule, and chlorine atoms are introduced into the side chain of the functionalized polyurethane molecule; the chlorine atoms introduced into the side chain of the functionalized polyurethane molecule can react with the tertiary amine structure on the modified vanadium dioxide to form a cross-linked network, thereby improving the mechanical properties of the phase-change temperature-control polyurethane material; the tensile strength of comparative example 2 is greater than the tensile strength of comparative example 3, indicating that boron-oxygen coordination bonds can be formed between the boron atoms of Si-OB in the main chain and the oxygen atoms in the adjacent molecular chains. The formation of the boron-oxygen coordination bonds also causes physical cross-linking between the polyurethane molecular chains, further improving the mechanical properties of the phase-change temperature-control polyurethane material.

[0062] By comparison, the rate of change of tensile strength in Examples 1 to 3 is less than that in Comparative Example 1, indicating that vanadium dioxide and 4-anilinotriethoxysilane are reacted to prepare pre-modified vanadium dioxide, and aniline groups are introduced on the surface of the pre-modified vanadium dioxide; the aniline groups introduced on the surface of the pre-modified vanadium dioxide undergo a Mills reaction with the nitroso groups on N,N-dimethyl-4-nitrosoaniline to prepare modified vanadium dioxide, and an azobenzene structure is generated on the surface of the modified vanadium dioxide; the azobenzene structure transforms from a trans conformation to a cis conformation under the action of ultraviolet light, and then transforms from a cis conformation to a trans conformation under irradiation with visible light having a wavelength greater than 440 nm. This reversible conformational change can absorb ultraviolet light, imparting excellent anti-aging properties to the phase-change temperature-control polyurethane material.

[0063] Test Example 3

[0064] Self-healing performance test

[0065] Testing method: Examples and comparative examples were prepared into standard bars according to GB / T 1040, and the tensile strength (X) of the standard bars was tested. The unstretched standard bars were cut with a 2 mm deep and 18 mm long slit in the middle. The bars were then placed in a mold and allowed to stand at 30°C for 24 hours. The healed standard bars were then tested for tensile strength (Y) using a tensile testing machine. The self-healing rates of the examples and comparative examples were calculated as follows: (tensile strength (Y) of the healed standard bars / original tensile strength (X) of the standard bars) × 100%. The results are shown in Table 3.

[0066] Table 3

[0067]

[0068] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 3, it can be found that the phase-change temperature-control polyurethane material prepared by the present invention has good self-healing properties.

[0069] By comparison, the self-healing rates of Examples 1 to 3 are greater than that of Comparative Example 3, indicating that phenylboric acid and 3-chloropropylmethyldimethoxysilane are polymerized and end-capped with 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane to prepare a borosiloxane oligomer, an Si-OB structure is introduced into the main chain of the borosiloxane oligomer molecule, and hydroxyl groups are introduced at both ends of the borosiloxane oligomer molecular chain; the hydroxyl groups introduced at both ends of the borosiloxane oligomer molecular chain enable it to participate in the polymerization reaction of polyurethane; the borosiloxane oligomer, 1,6-hexanediol and isophorone diisocyanate are reacted to form a polyurethane copolymer. Functionalized polyurethane is prepared by polymerization of acid esters; Si-OB structure is introduced into the main chain of the functionalized polyurethane molecule, and boron-oxygen coordination bonds can be formed between the boron atoms of Si-OB in the main chain and the oxygen atoms in the adjacent molecular chains. The boron-oxygen coordination bond is a dynamic reversible bond. The boron atom with a vacancy acts as an acceptor of the lone electron pair of the oxygen atom in the adjacent molecular chain, forming a non-bonded complex between molecules. The interaction between the boron and oxygen atoms causes dynamic physical cross-linking between the molecular chains. The bonding action is in a dynamic process of continuous dissociation and reformation, thereby making the phase change temperature-controlled polyurethane material have self-healing properties.

[0070] Test Example 4

[0071] Antibacterial performance test

[0072] Test method: Cut the examples and comparative examples into 18mm×18mm×6mm samples and sterilize them by ultraviolet irradiation for 8h; activate the Escherichia coli strain and prepare it to a concentration of 3×10 4 CFU / ml bacterial suspension; place the sample in the bacterial suspension and shake at 200 rpm for 10 minutes at room temperature. Dilute 1 ml of the bacterial suspension to 100-fold. Inoculate 1 ml of the diluted bacterial suspension onto agar medium and incubate at 37°C for 16 hours. Count the colonies according to the method in GB / T 15979 and calculate the inhibition rate. The results are shown in Table 4.

[0073] Table 4

[0074]

[0075] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 4, it can be found that the phase-change temperature-control polyurethane material prepared by the present invention has good antibacterial properties.

[0076] By comparison, the antibacterial rates of Examples 1 to 3 are greater than that of Comparative Example 1, indicating that the aniline group introduced on the surface of the pre-modified vanadium dioxide undergoes a Mills reaction with the nitroso group on N,N-dimethyl-4-nitrosoaniline to prepare the modified vanadium dioxide, and a tertiary amine structure is introduced on the surface of the modified vanadium dioxide. The tertiary amine structure introduced on the surface of the modified vanadium dioxide can react with the chlorine atom introduced on the side chain of the functionalized polyurethane molecule to form a quaternary ammonium salt structure. The generated quaternary ammonium salt structure has an antibacterial effect and can give the phase change temperature-control polyurethane material excellent antibacterial properties.

[0077] By comparison, the antibacterial rates of Examples 1 to 3 are greater than those of Comparative Examples 2 to 3, indicating that phenylboric acid and 3-chloropropylmethyldimethoxysilane are polymerized and end-capped with 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane to prepare a borosiloxane oligomer, chlorine atoms are introduced into the side chains of the borosiloxane oligomer molecules, and hydroxyl groups are introduced into both ends of the borosiloxane oligomer molecular chain; the hydroxyl groups introduced into both ends of the borosiloxane oligomer molecular chain enable it to participate in the polymerization reaction of polyurethane; borosiloxane oligomer, 1,6-hexanediol and isophorone diisocyanate are polymerized to prepare a functionalized polyurethane; chlorine atoms are introduced into the side chains of the functionalized polyurethane molecules; the chlorine atoms introduced into the side chains of the functionalized polyurethane molecules can react with the tertiary amine introduced into the modified vanadium dioxide to form a quaternary ammonium salt structure, and the generated quaternary ammonium salt structure has an antibacterial effect, which can give the phase change temperature-control polyurethane material excellent antibacterial properties.

[0078] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A phase change temperature control polyurethane material, characterized in that: The phase-change temperature-control polyurethane material is prepared by reacting pre-modified vanadium dioxide and N,N-dimethyl-4-nitrosoaniline to obtain modified vanadium dioxide; polymerizing borosiloxane oligomer, 1,6-hexanediol and isophorone diisocyanate to obtain functionalized polyurethane; and uniformly mixing the functionalized polyurethane and modified vanadium dioxide, followed by compression molding. The pre-modified vanadium dioxide is prepared by reacting vanadium dioxide and 4-anilinotriethoxysilane; The borosiloxane oligomer is prepared by polymerizing phenylboronic acid and 3-chloropropylmethyldimethoxysilane and capping the polymer with 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane.

2. The method for preparing a phase-change temperature-controlling polyurethane material according to claim 1, characterized in that: The preparation method of the phase-change temperature-control polyurethane material comprises the following preparation steps: (1) Pre-modified vanadium dioxide, glacial acetic acid, and N,N-dimethylformamide were mixed uniformly in a mass ratio of 1:(0.6~0.8):(40~50), and ultrasonically dispersed for 20~30 min. N,N-dimethyl-4-nitrosoaniline (3~4 times the mass of the pre-modified vanadium dioxide) was added, and stirred at 50~54°C and 200~300 r / min for 4~5 h. The mixture was filtered, washed with anhydrous ethanol and deionized water for 3~5 times each, and dried at 70~80°C under vacuum conditions for 9~10 h to obtain modified vanadium dioxide. (2) Phenylboric acid and 3-chloropropylmethyldimethoxysilane were added to 1,4-dioxane (14-16 times the mass of phenylboric acid) in a molar ratio of 1:(1.2-1.3), stirred at 79-81°C and 200-300 r / min for 50-60 min, and a capping agent (0.11-0.13 times the mass of 3-chloropropylmethyldimethoxysilane) was added, and the stirring reaction was continued for 8-10 min. The mixture was cooled to room temperature, washed with a mixture of equal volumes of toluene and deionized water, and allowed to stand for stratification. The organic phase was taken and dried at 50-60°C under vacuum conditions for 8-10 h to obtain borosiloxane oligomers. (3) The borosiloxane oligomer, 1,6-hexanediol, dibutyltin dilaurate and butanone were mixed evenly, stirred at 10-30°C and 100-200 r / min for 10-12 minutes, heated to 76-78°C, and 2-2.2 times the mass of isophorone diisocyanate of the borosiloxane oligomer was added, and the reaction was continued with stirring for 4-5 hours. Anhydrous ethanol was added at 1-1.2 times the mass of isophorone diisocyanate and mixed evenly, and the mixture was continued with stirring for 5-7 minutes. The mixture was dried at 68-70°C under vacuum conditions for 10-12 hours to obtain a functionalized polyurethane. (4) Functionalized polyurethane and modified vanadium dioxide were added into an internal mixer at a mass ratio of 1:(0.03~0.05), stirred at 180~190℃ and 60~80r / min for 6~8min, placed in a molding machine for compression molding, and demolded after cooling to room temperature to obtain a phase change temperature-controlled polyurethane material.

3. The method for preparing a phase-change temperature-controlling polyurethane material according to claim 2, characterized in that: The preparation method of the pre-modified vanadium dioxide in step (1) is as follows: vanadium dioxide and anhydrous ethanol are uniformly mixed in a mass ratio of 1:(60~70), ultrasonically dispersed for 1.2~1.4h, aniline silane hydrolyzate of 7~8 times the mass of vanadium dioxide is added, stirred at 50~60°C and 100~200r / min for reaction for 2~2.2h, filtered, washed with anhydrous ethanol 3~5 times, and dried at 60~70°C under vacuum conditions for 9~10h to obtain pre-modified vanadium dioxide.

4. The method for preparing a phase-change temperature-controlling polyurethane material according to claim 3, characterized in that: The particle size of the vanadium dioxide is 2000 mesh.

5. The method for preparing a phase-change temperature-controlling polyurethane material according to claim 3, characterized in that: The preparation method of the aniline silane hydrolyzate comprises: uniformly mixing 4-anilinotriethoxysilane and deionized water in a mass ratio of 1:(20-22), stirring at 10-30° C. and 100-200 r / min for 10-12 minutes, adjusting the pH to 5.6-5.8 with an oxalic acid aqueous solution, and continuing stirring for 20-30 minutes to prepare the aniline silane hydrolyzate.

6. The method for preparing a phase-change temperature-controlling polyurethane material according to claim 5, characterized in that: The concentration of the oxalic acid aqueous solution is 1 mol / L.

7. The method for preparing a phase-change temperature-controlling polyurethane material according to claim 2, characterized in that: The capping agent in step (2) is: 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane.

8. The method for preparing a phase-change temperature-controlling polyurethane material according to claim 2, characterized in that: The mass ratio of the borosiloxane oligomer, 1,6-hexanediol, dibutyltin dilaurate, and butanone in step (3) is 1:(0.2-0.3):(0.03-0.05):(8-10).

9. The method for preparing a phase-change temperature-controlling polyurethane material according to claim 2, characterized in that: The process parameters of the compression molding in step (4) are as follows: setting the temperature of the upper and lower mold plates of the molding machine to 200-210°C, the pressure to 14-16 MPa, and the time to 7-9 minutes.

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