Heat-resistant packaging material, preparation method and application in solar cell

Abstract

The invention relates to the technical field of high polymer materials, in particular to a heat-resistant packaging material, a preparation method and application of the heat-resistant packaging material in solar cells. The preparation method comprises the following steps: compounding azide polyurethane acrylate and propargyl oxybenzophenone by utilizing a click chemical reaction to obtain ultraviolet absorption type polyurethane acrylate; the preparation method comprises the following steps: mixing an ethylene-vinyl acetate copolymer, ultraviolet absorption type polyurethane acrylate, an alkenyl zinc oxide / silicon carbide composite material, nano aluminum oxide, a tackifier gamma-glycidyl ether oxypropyl trimethoxy silane, an antioxidant and a photoinitiator, casting to form a film, cooling and drafting to obtain the heat-resistant packaging material. The material has heat-resistant heat-conducting property and ultraviolet aging resistance, is good in adhesive property, and can be used as a packaging material to be applied to solar cell packaging.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a heat-resistant packaging material, a preparation method and an application in solar cells. Background Art

[0002] Photovoltaic modules are prone to failure in complex environments. The main reason is that the packaging materials used in photovoltaic modules are prone to aging in the environment, which affects the service life of the modules. The main packaging materials currently include: ethylene-vinyl acetate copolymer, silicone resin, polyvinyl butyral, thermoplastic polyolefin and other materials. Among them, ethylene-vinyl acetate copolymer (EVA) is widely used as a packaging material in solar cell modules due to its excellent properties such as good melt fluidity and good bonding performance.

[0003] Although EVA material has good chemical resistance and excellent processing technology, due to the fact that the main chain of EVA is a linear straight chain structure, the resistance to ultraviolet aging and moisture-heat aging is poor, and aging degradation is prone to occur. At the same time, EVA itself is an insulating material with poor thermal conductivity and insufficient heat resistance stability, which limits its application in packaging materials. Prior art, such as Chinese patent application CN114437444A, discloses a UV-resistant and moisture-resistant EVA material and its preparation method and application, by adding maleic anhydride-styrene alternating copolymer microspheres, surfactants, cross-linking agents, ultraviolet light absorbers, antioxidants and other auxiliary agents dispersed with gas-phase silica to ethylene-vinyl acetate copolymer (EVA). Improve the weathering and moisture-resistant properties and thermal insulation properties of ethylene-vinyl acetate copolymer materials, and better apply them to various fields such as safety glass and photovoltaic packaging films. However, the EVA material prepared by it is cross-linked by a thermal cross-linking agent, and the degree of cross-linking is not easy to control. When used as a packaging material for component packaging, the production time is long; although the weathering and moisture-resistant properties are improved, the heat resistance and UV-resistant properties of the material itself still need to be improved. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a heat-resistant packaging material, a preparation method and an application in solar cells. The material has better heat resistance and thermal conductivity and resistance to ultraviolet aging, and has good bonding properties, and can be used as a packaging material for solar cell packaging.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A method for preparing a heat-resistant packaging material comprises the following steps:

[0007] Step 1, preparing a UV-absorbing polyurethane acrylate and olefinic zinc oxide / silicon carbide composite material;

[0008] Wherein, the ultraviolet absorbing polyurethane acrylate is prepared by the following steps:

[0009] Step (1), mixing 2,4-dihydroxybenzophenone with potassium carbonate, adding 3-bromopropyne and acetone in sequence, reacting, after the reaction is completed, filtering, rotary evaporating to remove the solvent acetone, and passing through a column to obtain propargyloxybenzophenone;

[0010] Step (2), adding a mixed solution of polyazido glycidyl ether dropwise to toluene diisocyanate, reacting after the addition is complete, and then adding p-hydroxyanisole and hydroxyethyl acrylate in sequence, and continuing the reaction, and then cooling, filtering, and purifying to obtain azidized polyurethane acrylate;

[0011] Azide polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide are mixed and reacted. After the reaction is completed, a precipitant is added to precipitate, filtered, a solvent is added to dissolve, and the precipitation and filtering operations are repeated once, and dried to obtain ultraviolet absorbing polyurethane acrylate;

[0012] The olefinic zinc oxide / silicon carbide composite material is prepared by the following steps:

[0013] The zinc acetate, ethanol and nano-silicon carbide are mixed, ultrasonically dispersed, an oxalic acid solution is added, stirred, aged, dried, and calcined to obtain a zinc oxide / silicon carbide composite material;

[0014] Vinyltrimethoxysilane, zinc oxide / silicon carbide composite material and ethanol aqueous solution are mixed, ultrasonically dispersed, reacted, and after the reaction is completed, filtered, washed and dried to obtain vinyl zinc oxide / silicon carbide composite material;

[0015] Step 2: Mix ethylene-vinyl acetate copolymer, ultraviolet absorbing polyurethane acrylate, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether, knead, cast into film, cool and stretch to obtain a heat-resistant packaging material.

[0016] Preferably, when preparing ultraviolet absorbing polyurethane acrylate in step 1, in step (1), the mass ratio of 2,4-dihydroxybenzophenone, potassium carbonate, 3-bromopropyne and acetone is 10-10.2:12-13:4.8-5:120-150; and the reaction conditions are: reacting at a temperature of 50-60° C. for 16-20 hours.

[0017] Preferably, in the column operation, the developing solvent is prepared by mixing ether and ethyl acetate in a volume ratio of 50:1.

[0018] Preferably, when preparing ultraviolet absorption type polyurethane acrylate in step 1, in step (2): the mixed solution of polyazide glycidyl ether is prepared by mixing and dissolving polyazide glycidyl ether, dibutyltin dilaurate and toluene; the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole and hydroxyethyl acrylate is 2.8-3:29.5-30:0.05-0.1:100-120:0.09-0.1:1.9-2.1; the dripping conditions of the mixed solution of polyazide glycidyl ether are: dripping for 20-30 minutes at a temperature of 60-70°C in a nitrogen atmosphere; the reaction conditions are: reacting at a temperature of 60-70°C for 0.5-1h; and the continued reaction conditions are: continuing the reaction at a temperature of 50-60°C for 1-2h.

[0019] Preferably, the purification operation includes: taking the filter cake after suction filtration, adding toluene and petroleum ether 6-8 times the mass of the filter cake in sequence to wash three times to obtain a crude reaction product, mixing and dissolving the crude reaction product with dichloromethane in a mass ratio, adding 20-25wt% of anhydrous magnesium sulfate in the crude reaction product to dry for 10-12h, filtering, taking the filtrate, and removing the solvent dichloromethane by rotary evaporation at a temperature of 20-30°C.

[0020] Preferably, when preparing ultraviolet absorbing polyurethane acrylate in step 1, in step (2): the mass ratio of azid polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide is 12:1-1.2:0.01-0.02:0.1-0.15:30-40; and the reaction conditions are: reacting in a nitrogen atmosphere at room temperature for 48-52 hours.

[0021] Preferably, the precipitant comprises diethyl ether and the solvent comprises N,N-dimethylformamide.

[0022] Preferably, in the step 1 of preparing the alkenyl zinc oxide / silicon carbide composite material: the mass ratio of zinc acetate, ethanol, nano-silicon carbide, and oxalic acid solution is 2.2-2.3:80-100:1.3-1.5:3, and the oxalic acid solution is prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2; the stirring conditions are: stirring at 65-75°C for 50-60min, and the aging time is 4-5h; the calcination conditions are: placing in a muffle furnace and calcining at a set temperature of 500°C for 1h.

[0023] Preferably, in the step 1 of preparing the alkenyl zinc oxide / silicon carbide composite material: the mass ratio of vinyltrimethoxysilane, zinc oxide / silicon carbide composite material, and 50 vol% ethanol aqueous solution is 0.3-0.4:1:100-150, and the ethanol aqueous solution is 50 vol% ethanol aqueous solution; the reaction conditions are: reacting at a temperature of 70-80°C for 2-3h.

[0024] Preferably, in the step 2, the mass ratio of ethylene-vinyl acetate copolymer, UV-absorbing polyurethane acrylate, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether is 100:20-25:18-20:10-12:4-5:0.8-1:0.5-0.6; the mixing conditions are: mixing at a speed of 50-80r / min and a temperature of 80-90°C for 8-10min; the thickness of the heat-resistant packaging material is 0.5-0.8mm.

[0025] Preferably, a heat-resistant packaging material is prepared by the method for preparing a heat-resistant packaging material as described above.

[0026] Preferably, an application of the heat-resistant packaging material as described above in a solar cell.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The invention prepares ultraviolet absorption type polyurethane acrylate with ultraviolet absorption ability by compounding polyurethane acrylate with benzophenone group having ultraviolet absorption function through click chemical reaction, and uses the polyurethane acrylate as ultraviolet absorber, and adds the composite material of alkenyl zinc oxide / silicon carbide as a thermal conductive filler, nano-alumina, tackifier γ-glycidyloxypropyltrimethoxysilane, antioxidant and photoinitiator into ethylene-vinyl acetate copolymer matrix material for mixing, so that the prepared packaging material has better heat resistance and thermal conductivity and anti-ultraviolet aging performance, and good bonding performance, and can be used as a packaging material for solar cell packaging;

[0029] According to the present invention, 2,4-dihydroxybenzophenone and 3-bromopropyne undergo nucleophilic substitution reaction to obtain propargyloxybenzophenone; polyazide glycidyl ether having an azide group is used as a polymerization monomer to undergo polymerization reaction with toluene diisocyanate, and is capped by hydroxyethyl acrylate to obtain azidized polyurethane acrylate having an azide side group and a carbon-carbon double bond end group; the polyurethane acrylate undergoes a click chemical reaction with propargyloxybenzophenone under the action of a catalyst, so that the benzophenone group having an ultraviolet absorption effect is used as a side chain to graft polyurethane acrylate; the obtained ultraviolet absorption type polyurethane acrylate has ultraviolet absorption ability, can be used as an ultraviolet absorber to improve the ultraviolet resistance of an ethylene-vinyl acetate copolymer substrate, and can also further improve the heat resistance of the ethylene-vinyl acetate copolymer substrate because the polyurethane segment has good mechanical properties and heat resistance, and the alkynyl group and the azide group generate a nitrogen-containing triazole ring structure with good heat resistance after the click chemical reaction;

[0030] The invention uses nano silicon carbide as a carrier to load zinc oxide particles to prepare a zinc oxide / silicon carbide composite material, grafts vinyl trimethoxysilane on the surface of the zinc oxide / silicon carbide composite material to obtain an olefin zinc oxide / silicon carbide composite material, and adds the olefin zinc oxide / silicon carbide composite material together with nano aluminum oxide, ultraviolet absorption type polyurethane acrylate, tackifier γ-glycidyl ether oxypropyl trimethoxysilane, antioxidant, and photoinitiator into an ethylene-vinyl acetate copolymer matrix material to obtain a packaging material; wherein the ultraviolet absorption type polyurethane acrylate and the olefin zinc oxide / silicon carbide composite material both contain carbon-carbon double bonds, can undergo a cross-linking reaction with the ethylene-vinyl acetate copolymer during ultraviolet irradiation to form a spatial network structure, and effectively improve the strength of the packaging material The invention discloses a novel encapsulation material comprising a zinc oxide / silicon carbide composite material and a nano-aluminum oxide composite material, which both have excellent thermal conductivity, and are added into ethylene-vinyl acetate copolymer as thermal conductive fillers, which can not only improve the thermal resistance and thermal conductivity of the encapsulation material, but also improve the anti-ultraviolet performance of the encapsulation material due to the ultraviolet absorption effect of the zinc oxide particles; γ-glycidyloxypropyltrimethoxysilane is used as a tackifier, and can synergistically improve the bonding performance and heat resistance of the encapsulation material with ultraviolet absorption type polyurethane acrylate; the encapsulation material prepared by the invention has excellent thermal resistance and thermal conductivity, anti-ultraviolet aging performance, and good bonding performance, and can be used as an encapsulation material for solar cell encapsulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a process flow chart for preparing heat-resistant packaging materials in the present invention;

[0032] Figure 2 It is a peel strength bar graph of samples 1-8 in the comprehensive performance test of the present invention;

[0033] Figure 3 It is a bar graph of the peel strength retention rate in the UV aging resistance and the wet heat aging resistance of samples 1-8 in the comprehensive performance test of the present invention. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than 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 work are within the scope of protection of the present invention.

[0035] Example 1

[0036] This embodiment discloses a method for preparing a heat-resistant packaging material, comprising the following steps:

[0037] Step 1, preparing a UV-absorbing polyurethane acrylate and olefinic zinc oxide / silicon carbide composite material;

[0038] Wherein, the ultraviolet absorbing polyurethane acrylate is prepared by the following steps:

[0039] Step (1), mixing 2,4-dihydroxybenzophenone with potassium carbonate, adding 3-bromopropyne and acetone in sequence, wherein the mass ratio of 2,4-dihydroxybenzophenone, potassium carbonate, 3-bromopropyne and acetone is 10:12:4.8:120, reacting at 50° C. for 20 hours, and after the reaction is completed, filtering with suction, taking the filtrate, removing the solvent acetone by rotary evaporation at 30° C., and passing through a column to obtain propargyloxybenzophenone;

[0040] The developing solvent in the column operation is prepared by mixing ether and ethyl acetate in a volume ratio of 50:1;

[0041] Step (2), in a nitrogen atmosphere and at a temperature of 60° C., a mixed solution of polyazido glycidyl ether is added dropwise to toluene diisocyanate, wherein the mixed solution of polyazido glycidyl ether is prepared by mixing and dissolving polyazido glycidyl ether, dibutyltin dilaurate, and toluene, and the dropping time is 20 min. After the dropping is completed, the mixture is reacted at a temperature of 60° C. for 1 h. After the reaction is completed, p-hydroxyanisole and hydroxyethyl acrylate are added in sequence, and the reaction is continued at a temperature of 50° C. for 2 h. After the reaction is completed, the mixture is cooled to room temperature, filtered, and the filter cake is taken. Toluene and petroleum ether with a mass of 6 times that of the filter cake are added in sequence to wash the filter cake three times to obtain a crude reaction product. The crude reaction product is mixed and dissolved with dichloromethane in a mass ratio, anhydrous magnesium sulfate with a mass ratio of 20 wt % of the crude reaction product is added and dried for 12 h, filtered, and the filtrate is taken. The solvent dichloromethane is removed by rotary evaporation at a temperature of 20° C. to obtain azidized polyurethane acrylate;

[0042] Among them, the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole, and hydroxyethyl acrylate is 2.8:29.5:0.05:100:0.09:1.9;

[0043] Azide polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide were mixed in a mass ratio of 12:1:0.01:0.1:30, and reacted for 48 hours in a nitrogen atmosphere at room temperature. After the reaction was completed, a crude reaction product was obtained, and ether of 4 times the mass of the crude reaction product was added for precipitation, and the product was filtered. The filter cake was taken, and N,N-dimethylformamide of 6 times the mass of the filter cake was added for dissolution, and the precipitation and filtering operations were repeated once, and the product was dried at 30° C. for 48 hours to obtain ultraviolet absorbing polyurethane acrylate;

[0044] The olefinic zinc oxide / silicon carbide composite material is prepared by the following steps:

[0045] Zinc acetate, ethanol and nano-silicon carbide were mixed, ultrasonically dispersed for 10 minutes, and an oxalic acid solution prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2 was added, and the mass ratio of zinc acetate, ethanol, nano-silicon carbide and oxalic acid solution was 2.2:80:1.5:3. The mixture was stirred at 65°C for 60 minutes, aged for 4 hours, dried at 70°C for 4 hours, and after drying, placed in a muffle furnace and calcined at a set temperature of 500°C for 1 hour to obtain a zinc oxide / silicon carbide composite material;

[0046] Vinyl trimethoxysilane, zinc oxide / silicon carbide composite material, and 50 vol% ethanol aqueous solution were mixed in a mass ratio of 0.3:1:100, ultrasonically dispersed for 20 minutes, reacted at 70°C for 3 hours, filtered after the reaction, and the filter cake was taken, and ethanol 6 times the mass of the filter cake was added for washing, and dried at 50°C for 24 hours to obtain an olefinic zinc oxide / silicon carbide composite material;

[0047] Step 2: Mix ethylene-vinyl acetate copolymer, UV-absorbing polyurethane acrylate, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether in a mass ratio of 100:20:18:12:4:0.8:0.5, knead at a speed of 50 r / min and a temperature of 80°C for 10 min, cast into a film, and cool and stretch to obtain a heat-resistant packaging material with a thickness of 0.5 mm.

[0048] Example 2

[0049] This embodiment discloses a method for preparing a heat-resistant packaging material, comprising the following steps:

[0050] Step 1, preparing a UV-absorbing polyurethane acrylate and olefinic zinc oxide / silicon carbide composite material;

[0051] Wherein, the ultraviolet absorbing polyurethane acrylate is prepared by the following steps:

[0052] Step (1), mixing 2,4-dihydroxybenzophenone with potassium carbonate, adding 3-bromopropyne and acetone in sequence, wherein the mass ratio of 2,4-dihydroxybenzophenone, potassium carbonate, 3-bromopropyne and acetone is 10.05:12.3:4.85:130, reacting at 55° C. for 18 hours, and after the reaction is completed, filtering with suction, taking the filtrate, removing the solvent acetone by rotary evaporation at 35° C., and passing through a column to obtain propargyloxybenzophenone;

[0053] The developing solvent in the column operation is prepared by mixing ether and ethyl acetate in a volume ratio of 50:1;

[0054] Step (2), in a nitrogen atmosphere and at a temperature of 60° C., a mixed solution of polyazido glycidyl ether is added dropwise to toluene diisocyanate, wherein the mixed solution of polyazido glycidyl ether is prepared by mixing and dissolving polyazido glycidyl ether, dibutyltin dilaurate, and toluene, the dropping time is 25 min, and after the dropping is completed, the mixture is reacted at a temperature of 60° C. for 0.8 h. After the reaction is completed, p-hydroxyanisole and hydroxyethyl acrylate are added in sequence, and the reaction is continued at a temperature of 50° C. for 1.5 h. After the reaction is completed, the mixture is cooled to room temperature, filtered, and the filter cake is taken. Toluene and petroleum ether with a mass of 6 times that of the filter cake are added in sequence to wash the mixture three times to obtain a crude reaction product, the crude reaction product is mixed and dissolved with dichloromethane in a mass ratio, anhydrous magnesium sulfate with a mass ratio of 20 wt % of the crude reaction product is added, and the mixture is dried for 11 h, filtered, and the filtrate is taken. The solvent dichloromethane is removed by rotary evaporation at a temperature of 25° C. to obtain azidized polyurethane acrylate;

[0055] Among them, the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole, and hydroxyethyl acrylate is 2.85:29.6:0.06:105:0.09:1.95;

[0056] Azide polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide were mixed in a mass ratio of 12:1.05:0.01:0.12:35, and reacted for 48 hours in a nitrogen atmosphere at room temperature. After the reaction was completed, a crude reaction product was obtained, and ether of 4 times the mass of the crude reaction product was added for precipitation, and the product was filtered. The filter cake was taken, and N,N-dimethylformamide of 6 times the mass of the filter cake was added for dissolution, and the precipitation and filtering operations were repeated once, and the product was dried at 35° C. for 44 hours to obtain ultraviolet absorbing polyurethane acrylate;

[0057] The olefinic zinc oxide / silicon carbide composite material is prepared by the following steps:

[0058] Zinc acetate, ethanol and nano-silicon carbide were mixed, ultrasonically dispersed for 10 minutes, and an oxalic acid solution prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2 was added, and the mass ratio of zinc acetate, ethanol, nano-silicon carbide and oxalic acid solution was 2.23:85:1.45:3. The mixture was stirred at 65°C for 55 minutes, aged for 4 hours, dried at 75°C for 4 hours, and after drying, placed in a muffle furnace and calcined at a set temperature of 500°C for 1 hour to obtain a zinc oxide / silicon carbide composite material;

[0059] Vinyl trimethoxysilane, zinc oxide / silicon carbide composite material, and 50 vol% ethanol aqueous solution were mixed in a mass ratio of 0.33:1:120, ultrasonically dispersed for 25 minutes, reacted at 70°C for 2.5 hours, filtered after the reaction, and the filter cake was taken, washed with 7 times the mass of ethanol, and dried at 50°C for 22 hours to obtain an olefinic zinc oxide / silicon carbide composite material;

[0060] Step 2: Mix ethylene-vinyl acetate copolymer, UV-absorbing polyurethane acrylate, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether in a mass ratio of 100:22:18.5:11.5:4.3:0.85:0.53, knead at a speed of 60 r / min and a temperature of 80°C for 9 minutes, cast into a film, and cool and stretch to obtain a heat-resistant packaging material with a thickness of 0.6 mm.

[0061] Example 3

[0062] This embodiment discloses a method for preparing a heat-resistant packaging material, comprising the following steps:

[0063] Step 1, preparing a UV-absorbing polyurethane acrylate and olefinic zinc oxide / silicon carbide composite material;

[0064] Wherein, the ultraviolet absorbing polyurethane acrylate is prepared by the following steps:

[0065] Step (1), mixing 2,4-dihydroxybenzophenone with potassium carbonate, adding 3-bromopropyne and acetone in sequence, wherein the mass ratio of 2,4-dihydroxybenzophenone, potassium carbonate, 3-bromopropyne and acetone is 10.1:12.5:4.9:135, reacting at 55° C. for 18 hours, and after the reaction is completed, filtering with suction, taking the filtrate, removing the solvent acetone by rotary evaporation at 35° C., and passing through a column to obtain propargyloxybenzophenone;

[0066] The developing solvent in the column operation is prepared by mixing ether and ethyl acetate in a volume ratio of 50:1;

[0067] Step (2), in a nitrogen atmosphere and at a temperature of 65° C., a mixed solution of polyazido glycidyl ether is added dropwise to toluene diisocyanate, wherein the mixed solution of polyazido glycidyl ether is prepared by mixing and dissolving polyazido glycidyl ether, dibutyltin dilaurate, and toluene, the dropping time is 25 min, and after the dropping is completed, the mixture is reacted at a temperature of 65° C. for 0.8 h. After the reaction is completed, p-hydroxyanisole and hydroxyethyl acrylate are added in sequence, and the reaction is continued at a temperature of 55° C. for 1.5 h. After the reaction is completed, the mixture is cooled to room temperature, filtered, and the filter cake is taken. Toluene and petroleum ether with a mass of 7 times that of the filter cake are added in sequence to wash the mixture three times to obtain a crude reaction product, the crude reaction product is mixed and dissolved with dichloromethane in a mass ratio, anhydrous magnesium sulfate with a mass ratio of 23 wt % of the crude reaction product is added, and the mixture is dried for 11 h, filtered, and the filtrate is taken. The solvent dichloromethane is removed by rotary evaporation at a temperature of 25° C. to obtain azidized polyurethane acrylate;

[0068] Among them, the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole, and hydroxyethyl acrylate is 2.9:29.8:0.08:110:0.09:2;

[0069] Azide polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide were mixed in a mass ratio of 12:1.1:0.01:0.13:35, and reacted for 50 hours in a nitrogen atmosphere at room temperature. After the reaction was completed, a crude reaction product was obtained, and ether of 4 times the mass of the crude reaction product was added for precipitation, and the product was filtered. The filter cake was taken, and N,N-dimethylformamide of 7 times the mass of the filter cake was added for dissolution, and the precipitation and filtering operations were repeated once, and the product was dried at 35° C. for 44 hours to obtain ultraviolet absorbing polyurethane acrylate;

[0070] The olefinic zinc oxide / silicon carbide composite material is prepared by the following steps:

[0071] Zinc acetate, ethanol and nano-silicon carbide were mixed, ultrasonically dispersed for 13 minutes, and an oxalic acid solution prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2 was added, and the mass ratio of zinc acetate, ethanol, nano-silicon carbide and oxalic acid solution was 2.25:90:1.4:3. The mixture was stirred at 70°C for 55 minutes, aged for 4.5 hours, dried at 75°C for 3.5 hours, and after drying, placed in a muffle furnace and calcined at a set temperature of 500°C for 1 hour to obtain a zinc oxide / silicon carbide composite material;

[0072] Vinyl trimethoxysilane, zinc oxide / silicon carbide composite material, and 50 vol% ethanol aqueous solution were mixed in a mass ratio of 0.35:1:135, ultrasonically dispersed for 25 minutes, reacted at 75°C for 2.5 hours, filtered after the reaction, and the filter cake was taken, washed with 7 times the mass of ethanol, and dried at 55°C for 22 hours to obtain an olefinic zinc oxide / silicon carbide composite material;

[0073] Step 2: Mix ethylene-vinyl acetate copolymer, UV-absorbing polyurethane acrylate, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether in a mass ratio of 100:23:19:11:4.5:0.9:0.55, knead at a speed of 60 r / min and a temperature of 85°C for 9 minutes, cast into a film, and cool and stretch to obtain a heat-resistant packaging material with a thickness of 0.65 mm.

[0074] Example 4

[0075] This embodiment discloses a method for preparing a heat-resistant packaging material, comprising the following steps:

[0076] Step 1, preparing a UV-absorbing polyurethane acrylate and olefinic zinc oxide / silicon carbide composite material;

[0077] Wherein, the ultraviolet absorbing polyurethane acrylate is prepared by the following steps:

[0078] Step (1), mixing 2,4-dihydroxybenzophenone with potassium carbonate, adding 3-bromopropyne and acetone in sequence, wherein the mass ratio of 2,4-dihydroxybenzophenone, potassium carbonate, 3-bromopropyne and acetone is 10.15:12.8:4.95:140, reacting at 60° C. for 18 hours, and after the reaction is completed, filtering with suction, taking the filtrate, removing the solvent acetone by rotary evaporation at 35° C., and passing through a column to obtain propargyloxybenzophenone;

[0079] The developing solvent in the column operation is prepared by mixing ether and ethyl acetate in a volume ratio of 50:1;

[0080] Step (2), in a nitrogen atmosphere and at a temperature of 70° C., a mixed solution of polyazido glycidyl ether is added dropwise to toluene diisocyanate, wherein the mixed solution of polyazido glycidyl ether is prepared by mixing and dissolving polyazido glycidyl ether, dibutyltin dilaurate, and toluene, the dropping time is 25 min, and after the dropping is completed, the mixture is reacted at a temperature of 70° C. for 0.8 h. After the reaction is completed, p-hydroxyanisole and hydroxyethyl acrylate are added in sequence, and the reaction is continued at a temperature of 60° C. for 1.5 h. After the reaction is completed, the mixture is cooled to room temperature, filtered, and the filter cake is taken. Toluene and petroleum ether in an amount of 8 times the mass of the filter cake are added in sequence to wash the mixture three times to obtain a crude reaction product, the crude reaction product is mixed and dissolved with dichloromethane in a mass ratio, anhydrous magnesium sulfate in an amount of 25 wt % of the crude reaction product is added, and the mixture is dried for 11 h, filtered, and the filtrate is taken. The solvent dichloromethane is removed by rotary evaporation at a temperature of 25° C. to obtain azidized polyurethane acrylate;

[0081] Among them, the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole, and hydroxyethyl acrylate is 2.95:29.9:0.1:110:0.1:2.05;

[0082] Azide polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide were mixed in a mass ratio of 12:1.15:0.02:0.14:35, and reacted for 50 hours at room temperature in a nitrogen atmosphere. After the reaction was completed, a crude reaction product was obtained, and ether with a mass of 5 times that of the crude reaction product was added for precipitation, and the mixture was filtered. The filter cake was taken, and N,N-dimethylformamide with a mass of 8 times that of the filter cake was added for dissolution. The precipitation and filtering operations were repeated once, and the mixture was dried at 35° C. for 44 hours to obtain ultraviolet absorbing polyurethane acrylate.

[0083] The olefinic zinc oxide / silicon carbide composite material is prepared by the following steps:

[0084] Zinc acetate, ethanol and nano-silicon carbide were mixed, ultrasonically dispersed for 15 minutes, and an oxalic acid solution prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2 was added, and the mass ratio of zinc acetate, ethanol, nano-silicon carbide and oxalic acid solution was 2.28:95:1.35:3. The mixture was stirred at 75°C for 55 minutes, aged for 5 hours, dried at 80°C for 3.5 hours, and after drying, placed in a muffle furnace and calcined at a set temperature of 500°C for 1 hour to obtain a zinc oxide / silicon carbide composite material;

[0085] Vinyl trimethoxysilane, zinc oxide / silicon carbide composite material, and 50 vol% ethanol aqueous solution were mixed in a mass ratio of 0.38:1:140, ultrasonically dispersed for 25 minutes, reacted at 80°C for 2.5 hours, filtered after the reaction, and the filter cake was taken, and ethanol 8 times the mass of the filter cake was added for washing, and dried at 55°C for 22 hours to obtain an olefinic zinc oxide / silicon carbide composite material;

[0086] Step 2: Mix ethylene-vinyl acetate copolymer, UV-absorbing polyurethane acrylate, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether in a mass ratio of 100:24:19.5:10.5:4.8:0.95:0.58, knead at a speed of 70 r / min and a temperature of 85°C for 9 minutes, cast into a film, and cool and stretch to obtain a heat-resistant packaging material with a thickness of 0.7 mm.

[0087] Example 5

[0088] This embodiment discloses a method for preparing a heat-resistant packaging material, comprising the following steps:

[0089] Step 1, preparing a UV-absorbing polyurethane acrylate and olefinic zinc oxide / silicon carbide composite material;

[0090] Wherein, the ultraviolet absorbing polyurethane acrylate is prepared by the following steps:

[0091] Step (1), mixing 2,4-dihydroxybenzophenone with potassium carbonate, adding 3-bromopropyne and acetone in sequence, wherein the mass ratio of 2,4-dihydroxybenzophenone, potassium carbonate, 3-bromopropyne and acetone is 10.2:13:5:150, reacting at 60° C. for 16 hours, filtering after the reaction, taking the filtrate, removing the solvent acetone by rotary evaporation at 40° C., and passing through a column to obtain propargyloxybenzophenone;

[0092] The developing solvent in the column operation is prepared by mixing ether and ethyl acetate in a volume ratio of 50:1;

[0093] Step (2), in a nitrogen atmosphere and at a temperature of 70° C., a mixed solution of polyazido glycidyl ether is added dropwise to toluene diisocyanate, wherein the mixed solution of polyazido glycidyl ether is prepared by mixing and dissolving polyazido glycidyl ether, dibutyltin dilaurate, and toluene, the dropping time is 30 min, and after the dropping is completed, the mixture is reacted at a temperature of 70° C. for 0.5 h. After the reaction is completed, p-hydroxyanisole and hydroxyethyl acrylate are added in sequence, and the reaction is continued at a temperature of 60° C. for 1 h. After the reaction is completed, the mixture is cooled to room temperature, filtered, and the filter cake is taken. Toluene and petroleum ether in an amount of 8 times the mass of the filter cake are added in sequence to wash the mixture three times to obtain a crude reaction product, the crude reaction product is mixed and dissolved with dichloromethane in a mass ratio, anhydrous magnesium sulfate in an amount of 25 wt % of the crude reaction product is added, and the mixture is dried for 10 h, filtered, and the filtrate is taken. The solvent dichloromethane is removed by rotary evaporation at a temperature of 30° C. to obtain azidized polyurethane acrylate;

[0094] Among them, the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole, and hydroxyethyl acrylate is 3:30:0.1:120:0.1:2.1;

[0095] Azide polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide were mixed in a mass ratio of 12:1.2:0.02:0.15:40, and reacted for 52 hours at room temperature in a nitrogen atmosphere. After the reaction was completed, a crude reaction product was obtained, and ether with a mass of 5 times that of the crude reaction product was added for precipitation, and the mixture was filtered. The filter cake was taken, and N,N-dimethylformamide with a mass of 8 times that of the filter cake was added for dissolution. The precipitation and filtering operations were repeated once, and the mixture was dried at 40° C. for 40 hours to obtain ultraviolet absorbing polyurethane acrylate.

[0096] The olefinic zinc oxide / silicon carbide composite material is prepared by the following steps:

[0097] Zinc acetate, ethanol and nano-silicon carbide were mixed, ultrasonically dispersed for 15 minutes, and an oxalic acid solution prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2 was added, and the mass ratio of zinc acetate, ethanol, nano-silicon carbide and oxalic acid solution was 2.3:100:1.3:3. The mixture was stirred at 75°C for 50 minutes, aged for 5 hours, dried at 80°C for 3 hours, and after drying, placed in a muffle furnace and calcined at a set temperature of 500°C for 1 hour to obtain a zinc oxide / silicon carbide composite material;

[0098] Vinyl trimethoxysilane, zinc oxide / silicon carbide composite material, and 50 vol% ethanol aqueous solution were mixed in a mass ratio of 0.4:1:150, ultrasonically dispersed for 30 minutes, reacted at 80°C for 2 hours, filtered after the reaction, and the filter cake was taken, and ethanol 8 times the mass of the filter cake was added for washing, and dried at 60°C for 20 hours to obtain an olefinic zinc oxide / silicon carbide composite material;

[0099] Step 2: Mix ethylene-vinyl acetate copolymer, UV-absorbing polyurethane acrylate, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether in a mass ratio of 100:25:20:10:5:1:0.6, knead at a speed of 80 r / min and a temperature of 90°C for 8 minutes, cast into a film, and cool and stretch to obtain a heat-resistant packaging material with a thickness of 0.8 mm.

[0100] Comparative Example 1

[0101] This comparative example discloses a method for preparing a packaging material, comprising the following steps:

[0102] Step 1, preparing ultraviolet absorbing polyurethane acrylate;

[0103] Step (1), mixing 2,4-dihydroxybenzophenone with potassium carbonate, adding 3-bromopropyne and acetone in sequence, wherein the mass ratio of 2,4-dihydroxybenzophenone, potassium carbonate, 3-bromopropyne and acetone is 10:12:4.8:120, reacting at 50° C. for 20 hours, and after the reaction is completed, filtering with suction, taking the filtrate, removing the solvent acetone by rotary evaporation at 30° C., and passing through a column to obtain propargyloxybenzophenone;

[0104] The developing solvent in the column operation is prepared by mixing ether and ethyl acetate in a volume ratio of 50:1;

[0105] Step (2), in a nitrogen atmosphere and at a temperature of 60° C., a mixed solution of polyazido glycidyl ether is added dropwise to toluene diisocyanate, wherein the mixed solution of polyazido glycidyl ether is prepared by mixing and dissolving polyazido glycidyl ether, dibutyltin dilaurate, and toluene, and the dropping time is 20 min. After the dropping is completed, the mixture is reacted at a temperature of 60° C. for 1 h. After the reaction is completed, p-hydroxyanisole and hydroxyethyl acrylate are added in sequence, and the reaction is continued at a temperature of 50° C. for 2 h. After the reaction is completed, the mixture is cooled to room temperature, filtered, and the filter cake is taken. Toluene and petroleum ether with a mass of 6 times that of the filter cake are added in sequence to wash the filter cake three times to obtain a crude reaction product. The crude reaction product is mixed and dissolved with dichloromethane in a mass ratio, anhydrous magnesium sulfate with a mass ratio of 20 wt % of the crude reaction product is added and dried for 12 h, filtered, and the filtrate is taken. The solvent dichloromethane is removed by rotary evaporation at a temperature of 20° C. to obtain azidized polyurethane acrylate;

[0106] Among them, the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole, and hydroxyethyl acrylate is 2.8:29.5:0.05:100:0.09:1.9;

[0107] Azide polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide were mixed in a mass ratio of 12:1:0.01:0.1:30, and reacted for 48 hours in a nitrogen atmosphere at room temperature. After the reaction was completed, a crude reaction product was obtained, and ether of 4 times the mass of the crude reaction product was added for precipitation, and the product was filtered. The filter cake was taken, and N,N-dimethylformamide of 6 times the mass of the filter cake was added for dissolution, and the precipitation and filtering operations were repeated once, and the product was dried at 30° C. for 48 hours to obtain ultraviolet absorbing polyurethane acrylate;

[0108] Step 2: Mix ethylene-vinyl acetate copolymer, UV-absorbing polyurethane acrylate, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether in a mass ratio of 130:20:4:0.8:0.5, knead at a speed of 50 r / min and a temperature of 80°C for 10 min, cast into a film, cool and stretch, and obtain a packaging material with a thickness of 0.5 mm.

[0109] Comparative Example 2

[0110] This comparative example discloses a method for preparing a packaging material, comprising the following steps:

[0111] Step 1, preparing an olefinic zinc oxide / silicon carbide composite material;

[0112] Zinc acetate, ethanol and nano-silicon carbide were mixed, ultrasonically dispersed for 10 minutes, and an oxalic acid solution prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2 was added, and the mass ratio of zinc acetate, ethanol, nano-silicon carbide and oxalic acid solution was 2.2:80:1.5:3. The mixture was stirred at 65°C for 60 minutes, aged for 4 hours, dried at 70°C for 4 hours, and after drying, placed in a muffle furnace and calcined at a set temperature of 500°C for 1 hour to obtain a zinc oxide / silicon carbide composite material;

[0113] Vinyl trimethoxysilane, zinc oxide / silicon carbide composite material, and 50 vol% ethanol aqueous solution were mixed in a mass ratio of 0.3:1:100, ultrasonically dispersed for 20 minutes, reacted at 70°C for 3 hours, filtered after the reaction, and the filter cake was taken, and ethanol 6 times the mass of the filter cake was added for washing, and dried at 50°C for 24 hours to obtain an olefinic zinc oxide / silicon carbide composite material;

[0114] Step 2: Mix ethylene-vinyl acetate copolymer, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether in a mass ratio of 120:18:12:4:0.8:0.5, knead at a speed of 50 r / min and a temperature of 80°C for 10 min, cast into a film, and cool and stretch to obtain a packaging material with a thickness of 0.5 mm.

[0115] Comparative Example 3

[0116] This comparative example discloses a method for preparing a packaging material, comprising the following steps:

[0117] Step 1, preparing polyurethane acrylate and olefinic zinc oxide / silicon carbide composite materials;

[0118] Wherein, polyurethane acrylate is prepared by the following steps:

[0119] In a nitrogen atmosphere and at a temperature of 60° C., a mixed solution of polyazido glycidyl ether is added dropwise to toluene diisocyanate, wherein the mixed solution of polyazido glycidyl ether is prepared by mixing and dissolving polyazido glycidyl ether, dibutyltin dilaurate, and toluene. The dropping time is 20 min. After the dropping is completed, the mixture is reacted at a temperature of 60° C. for 1 h. After the reaction is completed, p-hydroxyanisole and hydroxyethyl acrylate are added in sequence, and the reaction is continued at a temperature of 50° C. for 2 h. After the reaction is completed, the mixture is cooled to room temperature, filtered, and the filter cake is taken. Toluene and petroleum ether with a mass of 6 times that of the filter cake are added in sequence to wash the mixture three times to obtain a crude reaction product. The crude reaction product is mixed and dissolved with dichloromethane in a mass ratio, and anhydrous magnesium sulfate with a mass of 20 wt% of the crude reaction product is added and dried for 12 h. The mixture is filtered, and the filtrate is taken. The solvent dichloromethane is removed by rotary evaporation at a temperature of 20° C. to obtain polyurethane acrylate.

[0120] Among them, the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole, and hydroxyethyl acrylate is 2.8:29.5:0.05:100:0.09:1.9;

[0121] The olefinic zinc oxide / silicon carbide composite material is prepared by the following steps:

[0122] Zinc acetate, ethanol and nano-silicon carbide were mixed, ultrasonically dispersed for 10 minutes, and an oxalic acid solution prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2 was added, and the mass ratio of zinc acetate, ethanol, nano-silicon carbide and oxalic acid solution was 2.2:80:1.5:3. The mixture was stirred at 65°C for 60 minutes, aged for 4 hours, dried at 70°C for 4 hours, and after drying, placed in a muffle furnace and calcined at a set temperature of 500°C for 1 hour to obtain a zinc oxide / silicon carbide composite material;

[0123] Vinyl trimethoxysilane, zinc oxide / silicon carbide composite material, and 50 vol% ethanol aqueous solution were mixed in a mass ratio of 0.3:1:100, ultrasonically dispersed for 20 minutes, reacted at 70°C for 3 hours, filtered after the reaction, and the filter cake was taken, and ethanol 6 times the mass of the filter cake was added for washing, and dried at 50°C for 24 hours to obtain an olefinic zinc oxide / silicon carbide composite material;

[0124] Step 2: Mix ethylene-vinyl acetate copolymer, polyurethane acrylate, alkenyl zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether in a mass ratio of 100:20:18:12:4:0.8:0.5, knead at a speed of 50 r / min and a temperature of 80°C for 10 min, cast into a film, and cool and stretch to obtain a packaging material with a thickness of 0.5 mm.

[0125] In the above embodiments and comparative examples: 2,4-dihydroxybenzophenone is from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No.: 131-56-6; toluene diisocyanate is from Shanghai McLean Biochemical Technology Co., Ltd., CAS No.: 26471-62-5; polyazide glycidyl ether is from Xi'an Qiyue Biotechnology Co., Ltd., product name polyazide glycidyl ether N3-GAP, product number Q-0345725, Mn=6000; nano silicon carbide is from Shanghai Aladdin Biochemical Technology Co., Ltd., with a particle size of 40nm; ethylene-vinyl acetate copolymer is from DuPont, USA, with a VA content of 33%, brand PV1650; nano alumina is from Shanghai McLean Biochemical Technology Co., Ltd., with a particle size of 30nm; antioxidant is from Sigma-Aldrich, product name antioxidant 1010, CAS No.: 6683-19-8.

[0126] Test example

[0127] The packaging materials prepared in Examples 1-5 and Comparative Examples 1-3 were subjected to comprehensive performance tests. The specific test results are shown in Tables 1 and 2:

[0128] Table 1

[0129]

[0130] Table 2

[0131]

[0132] The test of each index in Table 1 and Table 2 is based on the following standards: The adhesive performance is represented by the peel strength, and the test method includes: the packaging materials prepared in Examples 1-5 and Comparative Examples 1-3 are laminated and bonded to the glass test piece, and molded for 3 minutes at a pressure of 10 MPa and a temperature of 100°C by a flat vulcanizer, and the light intensity is 200 W / m 2The samples 1-8 were prepared by irradiating with UV light for 2 minutes under the conditions of , and the peel strengths of samples 1-8 were measured with reference to GB / T2790-1995 "Adhesive 180° Peel Strength Test Method - Flexible Material to Rigid Material"; the UV aging resistance was expressed by the peel strength retention rate, which was measured with reference to GB / T16422.3-2014 "Plastic Laboratory Light Source Exposure Test Method Part 3: Fluorescent UV Lamp", and the test time was 500h; the moisture and heat aging resistance was expressed by the peel strength retention rate, and the test conditions were: relative humidity 85%, temperature 85℃, and test time 500h.

[0133] It can be seen from the test results in Table 1 that the packaging material prepared by the present invention has better heat resistance and thermal conductivity and anti-ultraviolet aging performance, and good bonding performance.

[0134] The invention prepares an azidized polyurethane acrylate having an azide side group and a carbon-carbon double bond end group, and performs a click chemical reaction on the azidized polyurethane acrylate and propargyloxybenzophenone under the action of a catalyst, so that the benzophenone group having an ultraviolet absorption effect is used as a side chain grafted polyurethane acrylate. The obtained ultraviolet absorption type polyurethane acrylate has ultraviolet absorption ability and can be used as an ultraviolet absorber to improve the anti-ultraviolet performance of an ethylene-vinyl acetate copolymer substrate. At the same time, since the polyurethane chain segment has good mechanical properties and heat resistance, and the alkynyl group and the azide group generate a nitrogen-containing triazole ring structure with good heat resistance after the click chemical reaction, the heat resistance of the ethylene-vinyl acetate copolymer substrate can be further improved. The olefin zinc oxide / silicon carbide composite material, nano-aluminum oxide, ultraviolet absorption type polyurethane acrylate, and a tackifier γ-glycidyloxypropyl trimethoxysilane are prepared. Alkane, antioxidant and photoinitiator are added together to the ethylene-vinyl acetate copolymer matrix material. The ultraviolet absorbing polyurethane acrylate and the alkenyl zinc oxide / silicon carbide composite material both contain carbon-carbon double bonds, which can undergo cross-linking reaction with the ethylene-vinyl acetate copolymer during ultraviolet irradiation to form a spatial network structure, effectively improving the mechanical properties and heat aging resistance of the packaging material; the zinc oxide / silicon carbide composite material and nano-alumina both have excellent thermal conductivity, and adding the two as thermal conductive functional fillers to the ethylene-vinyl acetate copolymer can not only improve the heat resistance and thermal conductivity of the packaging material, but also improve the anti-ultraviolet performance of the packaging material due to the ultraviolet absorption effect of zinc oxide particles; γ-glycidyloxypropyltrimethoxysilane as a tackifier can synergistically improve the bonding performance and heat resistance of the packaging material with the ultraviolet absorbing polyurethane acrylate;

[0135] In Comparative Example 1, alkenyl zinc oxide / silicon carbide composite material and nano-aluminum oxide are not added, and the effect of improving the heat resistance and thermal conductivity of the substrate by the thermal conductive filler and improving the anti-ultraviolet aging performance of the substrate by the zinc oxide / silicon carbide composite material with ultraviolet absorption effect are lacking. Therefore, the thermal conductivity, anti-ultraviolet aging and anti-wet heat aging performance of Comparative Example 1 are reduced. At the same time, since the alkenyl zinc oxide / silicon carbide composite material will participate in the ultraviolet radiation cross-linking reaction, thereby improving the peel strength of the packaging material, the peel strength of Comparative Example 1 is lower than that of the embodiment;

[0136] In Comparative Example 2, no UV-absorbing polyurethane acrylate is added, and the effect of the benzophenone UV-absorbing group on improving the UV-resistant aging performance of the material is lacking. In addition, since the UV-absorbing polyurethane acrylate will participate in the UV-irradiation cross-linking reaction, the peel strength of the material will be improved. At the same time, the nitrogen-containing triazole ring structure and polyurethane segment in the polyurethane acrylate will also improve the heat resistance of the material. Therefore, the peel strength, UV-resistant aging and wet-heat aging resistance of Comparative Example 1 are not as good as those of the embodiment.

[0137] In Comparative Example 3, the polyurethane acrylate has no grafted benzophenone group, lacks the effect of the benzophenone ultraviolet light absorption group on improving the material's anti-ultraviolet aging performance, and lacks the effect of the nitrogen-containing triazole ring structure on improving the material's heat resistance. Therefore, the anti-ultraviolet aging and anti-wet heat aging performance of Comparative Example 3 are not as good as those of the embodiment.

[0138] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a heat-resistant packaging material, characterized in that: The following steps are involved: Step 1: mixing azidated polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate and N,N-dimethylformamide, and reacting them. After the reaction is completed, adding a precipitant to precipitate, filtering, adding a solvent to dissolve, repeating the precipitation and filtering operations, and drying to obtain ultraviolet absorbing polyurethane acrylate; Step 2: Mix ethylene-vinyl acetate copolymer, ultraviolet absorbing polyurethane acrylate, olefinic zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether, knead, cast into film, cool and stretch to obtain a heat-resistant packaging material.

2. The method for preparing a heat-resistant packaging material according to claim 1, characterized in that: The azidized polyurethane acrylate in step 1 is prepared by the following steps: A mixed solution of polyazide glycidyl ether is added dropwise to toluene diisocyanate, and after the addition is completed, the mixture is reacted. After the reaction is completed, p-hydroxyanisole and hydroxyethyl acrylate are added in sequence, and the reaction is continued. After the reaction is completed, the mixture is cooled, filtered, and purified to obtain azidized polyurethane acrylate. Among them, the mixed solution of polyazide glycidyl ether is prepared by mixing and dissolving polyazide glycidyl ether, dibutyltin dilaurate and toluene; the mass ratio of toluene diisocyanate, polyazide glycidyl ether, dibutyltin dilaurate, toluene, p-hydroxyanisole and hydroxyethyl acrylate is 2.8-3:29.5-30:0.05-0.1:100-120:0.09-0.1:1.9-2.1; the dripping conditions of the mixed solution of polyazide glycidyl ether are: dripping for 20-30 minutes at a temperature of 60-70°C in a nitrogen atmosphere; the reaction conditions are: reacting at a temperature of 60-70°C for 0.5-1h; and the continued reaction conditions are: continuing the reaction at a temperature of 50-60°C for 1-2h.

3. The method for preparing a heat-resistant packaging material according to claim 1, characterized in that: The propargyloxybenzophenone in step 1 is prepared by the following steps: Mix 2,4-dihydroxybenzophenone and potassium carbonate, add 3-bromopropyne and acetone in sequence, react, filter after the reaction, remove the solvent acetone by rotary evaporation, and pass through a column to obtain propargyloxybenzophenone; The mass ratio of 2,4-dihydroxybenzophenone, potassium carbonate, 3-bromopropyne and acetone is 10-10.2:12-13:4.8-5:120-150; the reaction conditions are: react at 50-60°C for 16-20h.

4. The method for preparing a heat-resistant packaging material according to claim 1, characterized in that: In the step 1, the mass ratio of azid polyurethane acrylate, propargyloxybenzophenone, cuprous bromide, sodium ascorbate, and N,N-dimethylformamide is 12:1-1.2:0.01-0.02:0.1-0.15:30-40; and the reaction conditions are: reacting in a nitrogen atmosphere at room temperature for 48-52 hours.

5. The method for preparing a heat-resistant packaging material according to claim 1, characterized in that: The alkenyl zinc oxide / silicon carbide composite material in step 2 is prepared by the following steps: Step (1), mixing zinc acetate, ethanol and nano-silicon carbide, ultrasonically dispersing, adding oxalic acid solution, stirring, aging, drying, and calcining after drying to obtain a zinc oxide / silicon carbide composite material; Step (2), mixing vinyltrimethoxysilane, zinc oxide / silicon carbide composite material and ethanol aqueous solution, ultrasonically dispersing, reacting, filtering, washing and drying after the reaction is completed to obtain vinyl zinc oxide / silicon carbide composite material.

6. The method for preparing a heat-resistant packaging material according to claim 5, characterized in that: In the step (1), the mass ratio of zinc acetate, ethanol, nano-silicon carbide and oxalic acid solution is 2.2-2.3:80-100:1.3-1.5:3, and the oxalic acid solution is prepared by mixing oxalic acid and ethanol in a mass ratio of 1:2; the stirring conditions are: stirring at a temperature of 65-75°C for 50-60 minutes, and the aging time is 4-5 hours; the calcination conditions are: placing in a muffle furnace and calcining at a set temperature of 500°C for 1 hour.

7. The method for preparing a heat-resistant packaging material according to claim 5, characterized in that: In the step (2), the mass ratio of vinyltrimethoxysilane, zinc oxide / silicon carbide composite material and 50 vol% ethanol aqueous solution is 0.3-0.4:1:100-150, and the ethanol aqueous solution is 50 vol% ethanol aqueous solution; the reaction conditions are: reacting at a temperature of 70-80°C for 2-3h.

8. The method for preparing a heat-resistant packaging material according to claim 1, characterized in that: In the step 2, the mass ratio of ethylene-vinyl acetate copolymer, ultraviolet absorption type polyurethane acrylate, alkenyl zinc oxide / silicon carbide composite material, nano-alumina, γ-glycidyloxypropyltrimethoxysilane, antioxidant, and benzoin dimethyl ether is 100:20-25:18-20:10-12:4-5:0.8-1:0.5-0.6; the mixing conditions are: mixing at a speed of 50-80r / min and a temperature of 80-90°C for 8-10min; the thickness of the heat-resistant packaging material is 0.5-0.8mm.

9. A heat-resistant packaging material prepared by the method for preparing a heat-resistant packaging material according to any one of claims 1 to 8.

10. Use of the heat-resistant packaging material according to claim 9 in solar cells.

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