Chemical bonding type rare earth light conversion film and preparation method and application thereof

Abstract

The invention provides a chemical bonding type rare earth light conversion film and a preparation method and application thereof, and the preparation method comprises the following steps: (1) mixing a rare earth light conversion material, a photoinitiator and master batch resin, and extruding to obtain a rare earth light conversion master batch; and (2) mixing the rare earth light conversion master batch obtained in the step (1) with matrix resin, and extruding to obtain the chemical bonding type rare earth light conversion film, the molecular structure of the rare earth light conversion material contains unsaturated double bonds; in at least one of the step (1) and the step (2), the step of ultraviolet irradiation is further included after extrusion is finished. According to the preparation method, the chemical bonding type rare earth light conversion film is prevented from being prepared in a mode of firstly polymerizing and then coordinating or firstly coordinating and then polymerizing, the process is simple, the cost is low, the migration, agglomeration and overflow phenomena of the rare earth light conversion material in the light conversion film can be greatly reduced, the light conversion service life of the light conversion film can be greatly prolonged, and the aging resistance of the light conversion film can be greatly improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer composite materials, and particularly relates to a chemically bonded rare earth light conversion film, a preparation method thereof, and an application thereof. Background Art

[0002] Rare earth light conversion films are a type of film material with light conversion functions and are widely used in various fields. For example, they can be used in agricultural films to convert ultraviolet light and green light, which are harmful or useless for plant photosynthesis in sunlight, into red light or blue light required for photosynthesis according to the needs of plant growth, strengthening the comprehensive utilization of sunlight by plants, and showing excellent photosynthetic effects, biological effects, and photosynthesis in greenhouse cultivation and shed film planting. The light functionalization of agricultural films is also one of the most promising research directions at present; in addition, they can also be used in encapsulation adhesive films for solar cells, materials for photobioreactors, etc.

[0003] At present, the preparation method of rare earth light conversion films is mainly to add rare earth light conversion materials to polymer materials, and the addition methods include physical mixing and chemical bonding. Physical mixing means that there is no chemical reaction between the light conversion material and the polymer material, that is, there is no chemical bond combination, including methods such as attachment dyeing and masterbatch blending. However, because the rare earth light conversion material and the film material have a simple physical interaction and their compatibility is generally poor, they will gradually precipitate or agglomerate during use, resulting in a decrease in uniformity and light transmittance, and even causing fluorescence quenching and reducing the light conversion life, which is one of the key factors restricting the large-scale popularization and application of rare earth light conversion films.

[0004] The chemical bonding method means directly bonding the light conversion material and the film material in a chemical bond manner, which can overcome the problems of precipitation or agglomeration of the light conversion agent caused by physical mixing, and is expected to achieve the coordinated functional life of rare earth light conversion film materials. However, the existing preparation methods of chemically bonded rare earth light conversion films mainly include two methods: polymerization first and then coordination or coordination first and then polymerization. However, due to reasons such as large steric hindrance or difficulty in dissolving the complex, the existing chemical bonding methods generally have disadvantages such as complex chemical processes, strict reaction conditions, high operating costs, and poor applicability, and there are great difficulties in industrial applications and no actual applications have been realized yet.

[0005] Therefore, developing a simple preparation method of a chemically bonded light conversion film suitable for the existing film material manufacturing process is an urgent problem to be solved in this field. Summary of the Invention

[0006] Aiming at the deficiencies of the existing technologies, the purpose of the present invention is to provide a chemically bonded rare earth light conversion film, a preparation method thereof and an application thereof. The preparation method of the chemically bonded rare earth light conversion film provided by the present invention can solve the problems in the prior art, such as complex chemical processes, stringent reaction conditions, high operation costs, and poor applicability during the preparation of the chemically bonded rare earth light conversion film. Without using the method of first polymerizing and then coordinating or first coordinating and then polymerizing, the chemically bonded rare earth light conversion film can be obtained, with a simple process and low cost.

[0007] To achieve this purpose, the present invention adopts the following technical solutions:

[0008] In the first aspect, the present invention provides a preparation method of a chemically bonded rare earth light conversion film, and the preparation method includes the following steps:

[0009] (1) Mix and extrude a rare earth light conversion material, a photoinitiator and a masterbatch resin to obtain a rare earth light conversion masterbatch;

[0010] (2) Mix and extrude the rare earth light conversion masterbatch obtained in step (1) with a matrix resin to obtain the chemically bonded rare earth light conversion film; an unsaturated double bond is contained in the molecular structure of the rare earth light conversion material; in at least one of step (1) and step (2), after the extrusion, a step of ultraviolet light irradiation is further included.

[0011] In the present invention, by using a rare earth light conversion material containing an unsaturated double bond, and under ultraviolet light irradiation, the photoinitiator will simultaneously generate free radicals for chemical bonding in both the resin material and the rare earth light conversion material, realizing the chemical bonding between the resin material and the rare earth light conversion material, so that the chemically bonded rare earth light conversion film can be directly prepared, avoiding the problem of difficult dissolution of the complex compound caused by the method of first polymerizing and then coordinating or first coordinating and then polymerizing in the prior art, with mild conditions and rapid reaction; and by connecting the rare earth light conversion material and the resin through chemical bonds, the stability of the combination of the rare earth light conversion material and the resin material is improved, the compatibility of the rare earth light conversion material in the resin is increased, the dissolution resistance and aging resistance of the rare earth light conversion film are improved, thereby extending the service life of the light conversion film material.

[0012] Preferably, the molecular formula of the rare earth light conversion material is REX a Y b ; where RE is a rare earth central ion, X is a flexible ligand, Y is a rigid ligand; a≥0 (for example, it can be 0, 1, 2, 3, 4, 5, 6, 7, 8, etc.), b≥0 (for example, it can be 0, 1, 2, 3, 4, 5, 6, 7, 8, etc.) and a and b are not both 0, and an unsaturated double bond is contained in the molecular structure of at least one of the X and Y ligands.

[0013] Preferably, the rare earth central ion includes Eu3+ , Tb 3+ , Sm 3+ , Dy 3+ , Nd 3+ , Ho 3+ , Er 3+ , Tm 3+ , Pr 3+ , Ce 3 + , Eu 2+ , Yb 2+ or Sm 2+ or at least one of Sm.

[0014] Preferably, the flexible ligand includes at least one of thioether ligands, β-diketone ligands, 4-hydroxy-1,5-naphthyridine ligands, aromatic heterocyclic carboxylic acid ligands, and substituted or unsubstituted C4-C20 alkyl ligands; the substituents of the substitution include at least one of carboxyl, sulfonic acid group, hydroxyl group, amino group, or halogen.

[0015] Preferably, the flexible ligand includes at least one of the following compounds:

[0016]

[0017] Preferably, the rigid ligand includes at least one of substituted or unsubstituted C6-C30 aryl ring ligands and substituted or unsubstituted C5-C30 heterocyclic ligands; the substituents of the substitution include at least one of carboxyl, sulfonic acid group, hydroxyl group, amino group, or halogen.

[0018] In the present invention, the C6-C30 may be, for example, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C18, C20, C22, C24, C26, C28, C30, etc.

[0019] In the present invention, the rigid ligand includes at least one of the following compounds:

[0020]

[0021] Preferably, the intensity of the ultraviolet light irradiation is independently 10-4000 mW / cm 2 , for example, it may be 10 mW / cm 2 , 20 mW / cm 2 , 50 mW / cm 2 , 100 mW / cm 2 , 150 mW / cm 2 , 200 mW / cm 2 , 250 mW / cm 2 , 300 mW / cm2 , 350 mW / cm 2 , 400 mW / cm 2 , 500 mW / cm 2 , 600 mW / cm 2 , 700 mW / cm 2 , 800 mW / cm 2 , 900 mW / cm 2 , 1000 mW / cm 2 , 1100 mW / cm 2 , 1200 mW / cm 2 , 1300 mW / cm 2 , 1400 mW / cm 2 , 1500 mW / cm 2 , 1600 mW / cm 2 , 1700 mW / cm 2 , 1800 mW / cm 2 , 2000 mW / cm 2 , 2500 mW / cm 2 , 3000 mW / cm 2 , 3500 mW / cm 2 , 4000 mW / cm 2 etc.

[0022] Preferably, the time of the ultraviolet light irradiation is 0.1 s to 15 min, and can be, for example, 0.1 s, 0.5 s, 1 s, 2 s, 5 s, 10 s, 15 s, 30 s, 35 s, 45 s, 60 s, 2 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, 12 min, 14 min, 15 min, etc.; more preferably 1 s to 5 min.

[0023] In the present invention, the intensity and time of the ultraviolet light irradiation are within a specific range, so that the light conversion performance and aging resistance performance of the chemically bonded rare earth light conversion film are better; if the time is too short or the intensity is too low, the input energy cannot make the photoinitiator generate a sufficient amount of free radicals, resulting in insufficient grafting of the rare earth light conversion material; if the time is too long or the intensity is too high, the photooxidation degradation reaction on the material surface will lead to a decline in related performance.

[0024] In the present invention, the light source of the ultraviolet light irradiation includes but is not limited to ultraviolet lamps, mercury lamps, UV plasmas, UV light-emitting diodes, UV xenon lamps, metal halide lamps, ultraviolet light curing devices or UVLED surface light sources, etc.

[0025] Preferably, the photoinitiator is a compound that generates active species for initiating monomer polymerization after absorbing light of a certain wavelength.

[0026] Preferably, the photoinitiator includes any one or a combination of at least two of benzoin ether initiators, benzil ketal initiators, acetophenone initiators, acylphosphine oxides, benzophenone and its derivatives, thioxanthone and its derivatives, anthraquinone and its derivatives.

[0027] Preferably, the photoinitiator includes at least one of 2,2-dimethoxybenzil ketal, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl), 4-vinylbenzophenone, 4-vinyl-4'-methoxybenzophenone, 4-allyloxy-2-hydroxybenzophenone, 4-allyloxybenzophenone, 4-acryloyloxy-2-hydroxybenzophenone, 4-acryloyloxybenzophenone, 2-hydroxy-4-(methacryloyloxy)benzophenone, 3-isopentenyl-2,4,6-trihydroxybenzophenone, 4,4-diazidostilbene-2,2-disulfonic acid sodium salt, α-arylvinyl azide, vinyl azide compound, 4-(bromomethyl)benzophenone, 4-hydroxybenzophenone, 2,2'-dihydroxybenzophenone, 4,4'-dihydroxybenzophenone, 4-chloro-4'-hydroxybenzophenone, 2-hydroxy-5-chlorobenzophenone, 2,3,4-trihydroxybenzophenone, phenyl salicylate, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2,4-dihydroxybenzene, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-(2'-hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole, resorcinol monobenzoate.

[0028] Preferably, the mass ratio of the photoinitiator to the masterbatch resin is (0.1-30):(40-99.8), wherein the specific values in (0.1-30) can be, for example, 0.1, 0.5, 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc.; the specific values in (40-99.8) can be, for example, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, etc.

[0029] Preferably, the masterbatch resin and the matrix resin each independently comprise at least one of polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), thermoplastic elastomer, polyvinyl chloride (PVC), polystyrene (PS), polypropylene (PP), polyvinylidene chloride (PVDC), polyamide (PA), polyester (PET), polyurethane (PU), polyvinyl alcohol (PVA), polyvinyl acetate (PVAC), epoxy resin (EP), polyacrylonitrile (PAN), polycarbonate (PC), polytetrafluoroethylene (PTFE).

[0030] In the present invention, the thermoplastic elastomer includes TPU elastomer, TPO elastomer, TPE elastomer, TPEE elastomer, etc.

[0031] Preferably, the mass ratio of the rare earth light conversion material to the masterbatch resin in step (1) is (0.1-30):(70-99.9); wherein, the specific values in (0.1-30) can be, for example, 0.1, 0.5, 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc.; the specific values in (70-99.9) can be, for example, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, etc.

[0032] Preferably, the mixed materials in step (1) further include a crosslinking agent, and the crosslinking agent is a compound containing at least 2 unsaturated double bonds, and the at least 2 unsaturated double bonds can be, for example, 2, 3, 4, 5, 6, etc.

[0033] Preferably, the crosslinking agent includes at least one of dicumyl peroxide (DCP), bis(tert-butylperoxyisopropyl)benzene (BIPB), trihydroxypropane diallyl ether (TMPDE), ethylene glycol dimethacrylate (EGDMA), diethylene glycol divinyl ether (DEGDVE), triallyl cyanurate (TAC), triallyl isocyanurate (TAIC), trimethylolpropane triacrylate (TMPTMA), or pentaerythritol tetraallyl ether (PETAE).

[0034] Preferably, the mass percentage content of the crosslinking agent is 0.01%-5%, and can be, for example, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.5%, 0.8%, 1.0%, 1.2%, 1.4%, 1.6%, 1.8%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, etc.

[0035] Preferably, the mass ratio of the rare earth light conversion masterbatch described in step (2) to the matrix resin is (1-30):(40-99). Among them, specific values in (1-30) can be, for example, 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc.; specific values in (40-99) can be, for example, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, etc.

[0036] Preferably, the mixed materials in step (2) further include additives.

[0037] Preferably, the mass ratio of the additives to the matrix resin is (1-30):(40-98). Among them, specific values in (1-30) can be, for example, 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc.; specific values in (40-98) can be, for example, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, etc.

[0038] Preferably, the additives are obtained by mixing and extruding a first additive and a first resin.

[0039] In the present invention, the temperature for mixing the first additive and the first resin is 25-400 °C, the time is 1 s-90 min; the temperature for extrusion is 80-400 °C.

[0040] Preferably, the mass ratio of the first additive to the first resin is (0.1-30):(40-99.9); among them, specific values in (0.1-30) can be, for example, 0.1, 0.5, 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc.; specific values in (40-99.9) can be, for example, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, etc.

[0041] Preferably, the first additive includes at least one of an antioxidant, an ultraviolet absorber, a nucleating agent, a plasticizer, a toughening agent, a stabilizer, a dispersant, a lubricant, a colorant, a light stabilizer, or an antistatic agent.

[0042] Preferably, the first resin, the masterbatch resin, and the matrix resin are selected from the same range, and the three may be the same or different.

[0043] Preferably, the temperature of the mixing in steps (1) and (2) is independently 25 to 400 °C, for example, it can be 25 °C, 40 °C, 60 °C, 80 °C, 100 °C, 120 °C, 140 °C, 160 °C, 180 °C, 200 °C, 220 °C, 240 °C, 260 °C, 280 °C, 300 °C, 320 °C, 340 °C, 360 °C, 380 °C, 400 °C, etc.; the mixing time is independently 1 s to 90 min, for example, it can be 1 s, 2 s, 4 s, 6 s, 8 s, 10 s, 20 s, 30 s, 40 s, 50 s, 1 min, 2 min, 3 min, 5 min, 6 min, 8 min, 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, 70 min, 80 min, 90 min, etc.

[0044] In the present invention, the mixing equipment includes but is not limited to magnetic stirrers, mechanical stirrers, kneaders, high-speed mixers, sand mills, open mills, internal mixers, twin-screw extruders, etc.

[0045] Preferably, the temperature of the extrusion in steps (1) and (2) is independently 80 to 400 °C, for example, it can be 80 °C, 100 °C, 120 °C, 140 °C, 160 °C, 180 °C, 200 °C, 220 °C, 240 °C, 260 °C, 280 °C, 300 °C, 320 °C, 340 °C, 360 °C, 380 °C, 400 °C, etc.

[0046] In the present invention, the extrusion equipment includes but is not limited to twin-screw extruders, single-screw extruders, extrusion granulators, multi-layer co-extrusion blown film machines, flat vulcanizers, vacuum laminating machines, calenders, cast film machines, film drawing machines, etc.; the extrusion molding method can adopt conventional methods in the prior art, including but not limited to one or several of extrusion blow molding, calendering, casting, biaxial stretching, etc.

[0047] As a preferred technical solution of the present invention, the preparation method includes the following steps:

[0048] (1) Mix the rare earth light conversion material, the photoinitiator, the masterbatch resin, and optionally the crosslinking agent at 25 to 400 °C for 1 s to 90 min, then extrude at 80 to 400 °C, and then irradiate with ultraviolet light having an intensity of 10 to 4000 mW / cm 2 for 0.1 s to 15 min to obtain a chemically bonded rare earth light conversion masterbatch;

[0049] (2) Mix the chemically bonded rare earth light conversion masterbatch obtained in step (1) with the matrix resin and optional additives at 25 - 400 °C for 1 s - 90 min, and then extrude at 80 - 400 °C to obtain the chemically bonded rare earth light conversion film;

[0050] Or

[0051] (11) Mix the rare earth light conversion material, photoinitiator, masterbatch resin and optional crosslinking agent at 25 - 400 °C for 1 s - 90 min, and then extrude at 80 - 400 °C to obtain a physically blended rare earth light conversion masterbatch;

[0052] (12) Mix the physically blended rare earth light conversion masterbatch obtained in step (11) with the matrix resin and optional additives at 25 - 400 °C for 1 s - 90 min, and then extrude at 80 - 400 °C, and then irradiate with ultraviolet light with an intensity of 10 - 4000 mW / cm 2 for 0.1 s - 15 min to obtain the chemically bonded rare earth light conversion film; the molecular structure of the rare earth light conversion material contains unsaturated double bonds.

[0053] In the present invention, in the preparation method, through physical mixing combined with ultraviolet light irradiation, the masterbatch or matrix resin and the rare earth light conversion material are bonded together by chemical bonds, avoiding the precipitation or agglomeration of the rare earth light conversion material in the resin, resulting in a decrease in uniformity and light transmittance; and the process is simple, avoiding the defects caused by the two methods of polymerization first and then coordination or coordination first and then polymerization, and is suitable for industrial production.

[0054] In the second aspect, the present invention provides a chemically bonded rare earth light conversion film, and the chemically bonded rare earth light conversion film is prepared by using the preparation method according to the first aspect.

[0055] Preferably, the chemically bonded rare earth light conversion film includes a single-layer structure or a multi-layer structure.

[0056] Preferably, in the multi-layer structure, the number of layers ≥ 2, for example, it can be 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, etc.

[0057] Preferably, in the multi-layer structure, it includes at least one rare earth light conversion layer; the rare earth light conversion layer is the chemically bonded rare earth light conversion film.

[0058] In the present invention, the single-layer structure refers to directly extruding the material of the rare earth light conversion film to obtain a single-layer rare earth light conversion film; the multi-layer structure refers to co-extruding the material of the rare earth light conversion film with multi-layer materials to obtain a rare earth light conversion film with a multi-layer structure.

[0059] In the present invention, when the rare earth light conversion film is a multi-layer structure, it is preferred that the rare earth light conversion layer is located in the middle to reduce contact with the external environment, further reduce the migration and agglomeration of the rare earth light conversion material in the film material, and further improve the light conversion life of the rare earth light conversion film.

[0060] Preferably, in the multi-layer structure, other functional layers are further included.

[0061] In the present invention, the other functional layers refer to multi-layer co-extrusion of functional materials and the materials of the rare earth light conversion film to obtain a multi-functional rare earth light conversion film; the other functional layers include, but are not limited to, an ultraviolet resistance layer, a heat insulation layer, an antistatic layer, a toughening layer, a water or gas barrier layer, etc.

[0062] In a third aspect, the present invention provides an application of the chemical bond type rare earth light conversion film as described in the second aspect in an agricultural film, a photovoltaic film or a soft light bioreactor, preferably a soft light bioreactor.

[0063] Preferably, the soft light bioreactor can be used for culturing microalgae or other photosynthetic microorganisms.

[0064] The numerical ranges described in the present invention not only include the above-listed point values, but also include any point values between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the ranges.

[0065] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0066] In the present invention, by using a rare earth light conversion material containing unsaturated double bonds, and in the presence of a photoinitiator and under ultraviolet light irradiation, the rare earth light conversion material is chemically bonded to the resin to directly prepare a chemical bond type rare earth light conversion film, avoiding the problem of difficult dissolution of the complex caused by the methods of first polymerization and then coordination or first coordination and then polymerization in the prior art. The process is simple and convenient, with low cost, improving the binding stability of the rare earth light conversion material and the resin, reducing the migration, agglomeration and overflow of the rare earth light conversion material in the light conversion film, and can greatly improve the light conversion life of the light conversion film, being suitable for industrial production. Description of the Drawings

[0067] Figure 1 It is the infrared spectrum of the rare earth light conversion material described in Example 1;

[0068] Figure 2 It is the thermogravimetric graph of the rare earth light conversion material described in Example 1;

[0069] Figure 3a And Figure 3b They are respectively the excitation spectrum and absorption spectrum of the rare earth light conversion material described in Example 1;

[0070] Figure 4 SEM image of the chemically bonded rare-earth light conversion film described in Example 1;

[0071] Figure 5 Differential scanning calorimetry chart of the chemically bonded rare-earth light conversion film described in Example 1;

[0072] Figure 6a and Figure 6b are the excitation spectrum and absorption spectrum of the chemically bonded rare-earth light conversion film described in Example 1 respectively;

[0073] Figure 7a and Figure 7b are the excitation spectrum and absorption spectrum of the rare-earth light conversion film described in Comparative Example 1 respectively.

[0074] Figure 8a and Figure 8b are the comparison charts of the excitation spectra and absorption spectra of the chemically bonded rare-earth light conversion film described in Example 1 and the rare-earth light conversion film described in Comparative Example 1 before and after the aging test respectively.

[0075] Figure 9 Schematic diagram of the preparation method provided by the present invention;

[0076] Among them, 1 is the schematic diagram of the preparation method provided in Example 1; 2 is the schematic diagram of the preparation method provided in Example 3. Specific Embodiments

[0077] The technical solutions of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations to the present invention.

[0078] Example 1

[0079] This example provides a preparation method for a chemically bonded rare-earth light conversion film, which specifically includes the following steps:

[0080] (1) Add 6 parts of rare-earth light conversion material (Eu(TTA) 3 Phen), 6 parts of photoinitiator (4-vinylbenzophenone) and 88 parts of ethylene-vinyl acetate copolymer (ExxonMobil EscoreneTM Ultra LD 708.NM) into a high-speed mixer and mix at 80°C for 30 min. Extrude, cool and granulate at 200°C using a twin-screw extruder. At the same time, irradiate the extruded material with ultraviolet light at a light intensity of 1000 mW / cm 2 for 60 s to obtain a chemically bonded rare-earth light conversion masterbatch.

[0081] (2) Mix ethylene-vinyl acetate copolymer (ExxonMobil EscoreneTM Ultra LD 708.NM), the chemically bonded rare earth light conversion masterbatch obtained in step (1), and additives evenly at room temperature according to a mass ratio of 90:5:5, and then extrude and mold at 200 °C to obtain the chemically bonded rare earth light conversion film; the additives are obtained by mixing antioxidant 1098 and ethylene-vinyl acetate copolymer with a mass ratio of 10:90 evenly at 80 °C, and then extruding and molding at 200 °C and granulating.

[0082] In the present invention, Eu(TTA) 3 Phen is commercially available, and its infrared spectrum is as Figure 1 shown; the thermogravimetric spectrum is as Figure 2 shown; its excitation spectrum and absorption spectrum are respectively Figure 3a , 3b shown.

[0083] The morphology of the chemically bonded rare earth light conversion film obtained in Example 1 was characterized by scanning electron microscopy, and the results are as Figure 4 shown. The differential scanning calorimetry chart of the chemically bonded rare earth light conversion film is as Figure 5 shown; the excitation spectrum and absorption spectrum of the chemically bonded rare earth light conversion film are respectively as Figure 6a , 6b shown; the comparison charts of the excitation spectrum and absorption spectrum of the chemically bonded rare earth light conversion film before and after the aging test are as Figure 8a and Figure 8b shown.

[0084] Example 2

[0085] This example provides a preparation method of a chemically bonded rare earth light conversion film, which specifically includes the following steps:

[0086] (1) Add 8 parts of rare earth light conversion material (Eu(TTA) 2 (AA)Phen), 8.5 parts of photoinitiator 4-vinylbenzophenone, and 83.5 parts of ethylene-vinyl acetate copolymer (Wacker VINNAPAS B 60 ) into a kneader and mix at 50 °C for 40 min, extrude, cool, and granulate at 150 °C using a single-screw extruder. At the same time, irradiate the extruded material with ultraviolet light with an intensity of 800 mW / cm 2 for 2 min to obtain a chemically bonded rare earth light conversion masterbatch.

[0087] (2) Polyvinyl acetate (Wacker VINNAPAS B 60 ) The chemically bonded rare earth light conversion masterbatch obtained in step (1) and the auxiliary agent are mixed evenly at room temperature according to a mass ratio of 91:4:5, and then extruded and molded at 180°C to obtain the chemically bonded rare earth light conversion film; the auxiliary agent is obtained by mixing a nucleating agent TMY-4 and ethylene-vinyl acetate copolymer with a mass ratio of 5:95 evenly at 80°C, and then extruded and molded at 150°C and granulated.

[0088] Example 3

[0089] This example provides a method for preparing a chemically bonded rare earth light conversion film, which specifically includes the following steps:

[0090] (1) Add 15 parts of rare earth light conversion material (Sm(Sal) 3 Phen), 5 parts of photoinitiator 4-acryloyloxybenzophenone and 80 parts of ethylene-vinyl acetate copolymer into an open mill and mix at 160°C for 60 min. Use a vacuum laminating machine to extrude, cool and granulate at 180°C to obtain a physically blended rare earth light conversion masterbatch.

[0091] (2) Mix polyethylene, the physically blended rare earth light conversion masterbatch obtained in step (1) and the auxiliary agent evenly at room temperature according to a mass ratio of 93:2:5, and then extrude and mold at 180°C. At the same time, irradiate the extruded material with ultraviolet light with an intensity of 1200 mW / cm 2 for 3 min to obtain the chemically bonded rare earth light conversion film; the auxiliary agent is obtained by mixing an ultraviolet absorber UV-531 and polyethylene (ExxonMobil ExxonMobil TM LDPE LD 136.MN) with a mass ratio of 5:95 evenly at 80°C, and then extruded and molded at 180°C and granulated.

[0092] Example 4

[0093] This example provides a method for preparing the chemically bonded rare earth light conversion film, and the specific steps include:

[0094] (1) Add 3 parts of rare earth light conversion material (Eu(TTA) 3 Phen), 5 parts of photoinitiator 4-allyloxy-2-hydroxybenzophenone and 92 parts of ethylene-vinyl acetate copolymer into a sand mill and mix at 50°C for 30 min. Use a flat vulcanizer to extrude, cool and granulate at 150°C. At the same time, irradiate the extruded material with ultraviolet light with an intensity of 500 mW / cm 2 for 5 min to obtain a chemically bonded rare earth light conversion masterbatch.

[0095] (2) Co-extrude the rare earth light conversion intermediate layer material, the inner layer material, and the outer layer material in multiple layers, and the extrusion temperatures are 200 °C, 200 °C, and 200 °C respectively. A chemically bonded rare earth light conversion film including an inner layer, a rare earth light conversion intermediate layer, and an outer layer is obtained; the rare earth light conversion intermediate layer material includes PE resin, the chemically bonded rare earth light conversion masterbatch obtained in step (1), and an auxiliary agent in a mass ratio of 96:1.5:2.5 (using a nucleating agent TMY-4A and PE resin in a mass ratio of 5:95 and mixing evenly at 80 °C, and then extruding and molding at 180 °C); the inner layer material and the outer layer material each independently include antioxidant 168, light stabilizer HS-625, ultraviolet absorber UV-531, and EVA resin in a mass ratio of 1:1:1:197.

[0096] Example 5

[0097] This example provides a preparation method of the chemically bonded rare earth light conversion film, and the specific steps include:

[0098] (1) Add 25 parts of rare earth light conversion material (Eu(TTA) 2 (AA)Phen), 10 parts of photoinitiator phenyl salicylate, and 95 parts of polyolefin elastomer (ExxonMobil Exact TM 5061) into a kneader and mix at 180 °C for 20 min, extrude, cool, and granulate at 220 °C using a twin-screw extruder. At the same time, irradiate the extruded material with ultraviolet light at a light intensity of 200 mW / cm 2 for 10 min to obtain a chemically bonded rare earth light conversion masterbatch.

[0099] (2) Co-extrude the inner layer material, the rare earth light conversion intermediate layer material, the second functional layer material, and the outer layer material through a multi-layer co-extrusion blown film machine, and the extrusion temperatures are 160 °C, 160 °C, 160 °C, and 160 °C respectively; a chemically bonded rare earth light conversion film including an inner layer, a rare earth light conversion layer, a second functional layer, and an outer layer stacked in sequence is obtained; the rare earth light conversion intermediate layer material includes PE resin, the chemically bonded rare earth light conversion masterbatch obtained in step (1), and an auxiliary agent in a mass ratio of 85:10:5 (using a nucleating agent TMY-4A and PE resin in a mass ratio of 2:98 and mixing evenly at 80 °C, and then extruding and molding at 180 °C); the inner layer material and the outer layer material each independently include antioxidant 1098, light stabilizer HS-362, ultraviolet absorber UV-326, and EVA resin in a mass ratio of 1:1:1:197; the second functional layer is a heat insulation layer, and the material of the second functional layer is antimony tin oxide.

[0100] Example 6

[0101] This embodiment provides a method for preparing a chemically bonded rare earth light conversion film. The difference from Embodiment 1 is only that in the raw materials for preparing the chemically bonded light conversion masterbatch, the total mass of the rare earth light conversion material, the photoinitiator, and the ethylene-vinyl acetate copolymer remains unchanged, and the mass ratio is 3:5:92. Other materials, structures, and preparation methods are the same as those in Embodiment 1.

[0102] Example 7

[0103] This embodiment provides a chemically bonded rare earth light conversion film. The difference from Application Example 1 is only that in the preparation method, the irradiation time in step (1) is 30 s, and other materials, structures, and preparation methods are the same as those in Embodiment 1.

[0104] Example 8

[0105] This embodiment provides a chemically bonded rare earth light conversion film. The difference from Application Example 1 is only that in the preparation method, the irradiation time in step (1) is 20 min, and other materials, structures, and preparation methods are the same as those in Embodiment 1.

[0106] Example 9

[0107] This embodiment provides a chemically bonded rare earth light conversion film. The difference from Embodiment 1 is only that in the preparation method, the irradiation intensity in step (1) is 200 mW / cm 2 , and other materials, structures, and preparation methods are the same as those in Embodiment 1.

[0108] Example 10

[0109] This embodiment provides a chemically bonded rare earth light conversion film. The difference from Embodiment 1 is only that in the preparation method, the irradiation intensity in step (1) is 4000 mW / cm 2 , and other materials, structures, and preparation methods are the same as those in Embodiment 1.

[0110] Example 11

[0111] This embodiment provides a method for preparing a rare earth light conversion film. The difference from Embodiment 1 is only that in the raw materials for preparing the chemically bonded light conversion masterbatch, 0.1 part of the crosslinking agent triallyl cyanurate is further included. Other materials, structures, and preparation methods are the same as those in Embodiment 1.

[0112] Comparative Example 1

[0113] This comparative example provides a method for preparing a rare earth light conversion film. The difference from Embodiment 1 is only that in the preparation method, ultraviolet light irradiation is not carried out in step (1), and other materials, structures, and preparation methods are the same as those in Embodiment 1.

[0114] In the present invention, the excitation spectrum and absorption spectrum of the rare earth light conversion thin film obtained in Comparative Example 1 are respectively as shown in Figure 7a and Figure 7b ; the comparison diagrams of the excitation spectrum and absorption spectrum of the rare earth light conversion thin film before and after the aging test are as shown in Figure 8a and Figure 8b .

[0115] Performance Test

[0116] (1) Dissolution resistance performance: Cut about 0.2 g of the film into pieces of 0.75 cm * 2.5 cm, put them into a non-woven bag, assemble the Soxhlet extraction reaction equipment, and then add 200 ml of ethyl acetate to the flat-bottom flask. After Soxhlet extraction at 90 °C for 24 h, wash the reacted film with absolute ethanol, dry it in an oven at 40 °C to constant weight, and obtain the film with accelerated dissolution of the light conversion material. After washing and drying the film, cut it into pieces of 0.75 × 0.75 cm. Take about 0.2 g of each sample and put it into an automatic moisture and ash analyzer, and weigh and ash it according to the set program. After the ashing is completed, dissolve it with 1% HCl and 0.5% HNO 3 make up the volume, and then measure the content of rare earth elements in the solution with a flame element absorption instrument, and calculate the retention rate of the light conversion agent in each film. The calculation formula is:

[0117]

[0118] wherein, S is the retention rate of the light conversion agent, %; C is the concentration of rare earth elements in the solution, mg / L; V is the volume of dissolution and volume makeup, L; m is the mass of the film, g; ω t is the doping amount of the light conversion agent in the light conversion film, %; ω m is the proportion of rare earth elements in the light conversion agent, %.

[0119] The specific test results are shown in Table 1.

[0120] (2) Aging experiment: Cut the film into 6 × 10 cm and put it into a mold, and then put it into an ultraviolet aging chamber. Set the aging program according to GB / T14522-2008 (8 h drying (0.76 W / (m 2 ·nm)), 50 °C; 0.25 h spraying; 3.75 h condensation, 50 °C). After 15 days of aging experiment, take out the film, cut it into pieces of 1 × 5 cm for light conversion test. The test conditions are as follows:

[0121] Light conversion test: The test slit is 0.2 nm, step is 1, interval is 0.2 s, absorption spectrum test: scanning range: 200 - 500 nm, emission peak: 612 nm; emission spectrum test: scanning range: 400 - 800 nm, emission peak: 389 nm. There are three parallel samples for each sample. Calculate the fluorescence emission intensity retention rate of the rare earth light conversion thin film after aging by the following formula.

[0122]

[0123] Wherein, R is the retention rate of fluorescence emission intensity, %; is the measured value at the average characteristic emission wavelength after exposure for t hours; is the measured value at the initial average characteristic emission wavelength.

[0124] The specific test results are shown in Table 1 as follows:

[0125] Table 1

[0126]

[0127]

[0128] As can be seen from the above table, for the chemically bonded rare earth light conversion thin film provided by the present invention, by using a rare earth light conversion material containing an unsaturated double bond, and in the presence of a photoinitiator and under ultraviolet light irradiation, a chemically bonded rare earth light conversion thin film can be directly prepared, avoiding the problem of poor solubility of the complex caused by the methods of first polymerization and then coordination or first coordination and then polymerization in the prior art. The process is simple and convenient, and the obtained chemically bonded rare earth light conversion thin film has a higher lifespan, better dissolution resistance and aging resistance.

[0129] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A preparation method of a chemically bonded rare earth light conversion film, characterized in that, the preparation method comprises the following steps: (1) Mixing and extruding a rare earth light conversion material, a photoinitiator and a masterbatch resin to obtain a rare earth light conversion masterbatch; (2) Mixing and extruding the rare earth light conversion masterbatch obtained in step (1) with a matrix resin to obtain the chemically bonded rare earth light conversion film; the molecular structure of the rare earth light conversion material contains an unsaturated double bond; in at least one of step (1) and step (2), after the extrusion, a step of ultraviolet light irradiation is further included.

2. The preparation method according to claim 1, characterized in that, The molecular formula of the rare earth light conversion material described in step (1) is REX a Y b ; where RE is a rare earth central ion, X is a flexible ligand, and Y is a rigid ligand; a≥0, b≥0 and a and b are not both 0 at the same time, and the molecular structure of at least one of the ligands X and Y contains an unsaturated double bond; Preferably, the rare earth central ion includes Eu 3+ , Tb 3+ , Sm 3+ , Dy 3+ , Nd 3+ , Ho 3+ , Er 3+ , Tm 3+ , Pr 3+ , Ce 3+ , Eu 2 + , Yb 2+ or Sm 2+ and at least one of them; preferably, the flexible ligand includes at least one of thioether ligands, β-diketone ligands, 4-hydroxy-1,5-naphthyridine ligands, aromatic heterocyclic carboxylic acid ligands, substituted or unsubstituted C4-C20 alkyl ligands; the substituents of the substitution include at least one of carboxyl, sulfonic acid group, hydroxyl group, amino group or halogen; preferably, the rigid ligand includes at least one of substituted or unsubstituted C6-C30 aromatic ring ligands, substituted or unsubstituted C5-C30 heterocyclic ligands; the substituents of the substitution include at least one of carboxyl, sulfonic acid group, hydroxyl group, amino group or halogen.

3. The preparation method according to claim 1, characterized in that, The intensity of the ultraviolet light irradiation is independently 10 to 4000 mW / cm 2 ; preferably, the time of the ultraviolet light irradiation is 0.1 s to 15 min, and more preferably 1 s to 5 min.

4. The preparation method according to any one of claims 1 to 3, characterized in that, the photoinitiator in step (1) is a compound that generates an active species for initiating monomer polymerization after absorbing light of a certain wavelength; preferably, the photoinitiator includes any one or a combination of at least two of benzoin ether initiators, benzil ketal initiators, acetophenone initiators, acylphosphine oxides, benzophenone and its derivatives, thioxanthone and its derivatives, anthraquinone and its derivatives; Preferably, the photoinitiator includes at least one of 2,2-dimethoxybenzil ketal, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl), 4-vinylbenzophenone, 4-vinyl-4'-methoxybenzophenone, 4-allyloxy-2-hydroxybenzophenone, 4-allyloxybenzophenone, 4-acryloyloxy-2-hydroxybenzophenone, 4-acryloyloxybenzophenone, 2-hydroxy-4-(methacryloyloxy)benzophenone, 3-isopentenyl-2,4,6-trihydroxybenzophenone, sodium 4,4'-azodistilbene-2,2'-disulfonate, α-arylalkenyl azide, vinyl azide compound, 4-(bromomethyl)benzophenone, 4-hydroxybenzophenone, 2,2'-dihydroxybenzophenone, 4,4'-dihydroxybenzophenone, 4-chloro-4'-hydroxybenzophenone, 2-hydroxy-5-chlorobenzophenone, 2,3,4-trihydroxybenzophenone, phenyl salicylate, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2,4-dihydroxybenzene, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-(2'-hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole, resorcinol monobenzoate; Preferably, the mass ratio of the photoinitiator to the masterbatch resin is (0.1-30):(40-99.8); Preferably, the masterbatch resin and the matrix resin each independently include at least one of polyethylene, ethylene-vinyl acetate copolymer, thermoplastic elastomer, polyvinyl chloride, polystyrene, polypropylene, polyvinylidene chloride, polyamide, polyester, polyurethane, polyvinyl alcohol, polyvinyl acetate, epoxy resin, polyacrylonitrile, polycarbonate, or polytetrafluoroethylene, etc.; Preferably, the mass ratio of the rare earth light conversion material to the masterbatch resin in step (1) is (0.1-30):(70-99.9); Preferably, the mixed materials in step (1) further include a crosslinking agent, and the crosslinking agent is a compound containing at least 2 unsaturated double bonds; Preferably, the crosslinking agent includes at least one of dicumyl peroxide, bis(tert-butylperoxyisopropyl)benzene, trihydroxypropane diallyl ether, ethylene glycol dimethacrylate, diethylene glycol divinyl ether, triallyl cyanurate, triallyl isocyanurate, trimethylolpropane triacrylate, or pentaerythritol tetraallyl ether; Preferably, the mass percentage content of the crosslinking agent is 0.01%-5%.

5. According to the preparation method according to any one of claims 1 to 4, characterized in that the mass ratio of the rare earth light conversion masterbatch to the matrix resin in step (2) is (1-30):(40-99); Preferably, the mixed materials in step (2) further include an auxiliary agent; Preferably, the mass ratio of the auxiliary agent to the matrix resin is (1-30):(40-98); Preferably, the auxiliary agent is obtained by mixing and extruding a first auxiliary agent and a first resin; Preferably, the mass ratio of the first auxiliary agent to the first resin in the auxiliary agent is (0.1-30):(40-99.9); Preferably, the first additive includes at least one of antioxidants, ultraviolet absorbers, nucleating agents, plasticizers, toughening agents, stabilizers, dispersants, lubricants, colorants, light stabilizers, antistatic agents, etc.; Preferably, the first resin, the masterbatch resin, and the matrix resin are selected from the same range, and the three can be the same or different.

6. The preparation method according to any one of claims 1 to 5, characterized in that, the temperature of the mixing in step (1) and step (2) is independently 25 to 400 °C, and the mixing time is independently 1 s to 90 min; Preferably, the temperature of the extrusion in step (1) and step (2) is independently 80 to 400 °C.

7. A preparation method according to any one of claims 1 to 6, characterized in that, the preparation method includes the following steps: (1) Mix the rare earth light conversion material, the photoinitiator, the masterbatch resin, and optionally the crosslinking agent at 25 to 400 °C for 1 s to 90 min, then extrude and mold at 80 to 400 °C, and then irradiate with ultraviolet light at a strength of 10 to 4000 mW / cm2 for 0.1 s to 15 min to obtain a chemically bonded rare earth light conversion masterbatch; (2) Mix the chemically bonded rare earth light conversion masterbatch obtained in step (1) with the matrix resin and optionally the additives at 25 to 400 °C for 1 s to 90 min, and then extrude and mold at 80 to 400 °C to obtain the chemically bonded rare earth light conversion film; or (11) Mix the rare earth light conversion material, the photoinitiator, the masterbatch resin, and optionally the crosslinking agent at 25 to 400 °C for 1 s to 90 min, and then extrude at 80 to 400 °C to obtain a physically blended rare earth light conversion masterbatch; (12) Mix the physically blended rare earth light conversion masterbatch obtained in step (11) with the matrix resin and optional additives at 25 - 400 °C for 1 s - 90 min, then extrude at 80 - 400 °C, and then irradiate under ultraviolet light with an intensity of 10 - 4000 mW / cm 2 for 0.1 s - 15 min to obtain the chemically bonded rare earth light conversion film; The molecular structure of the rare earth light conversion material contains unsaturated double bonds.

8. A chemically bonded rare earth light conversion film, characterized in that, the chemically bonded rare earth light conversion film is prepared by the preparation method according to any one of claims 1 to 7.

9. The chemically bonded rare earth light conversion film according to claim 8, characterized in that, the chemically bonded rare earth light conversion film includes a single-layer structure or a multi-layer structure; Preferably, in the multi-layer structure, the number of layers ≥ 2; Preferably, in the multi-layer structure, it includes at least one rare earth light conversion layer; the rare earth light conversion layer is the chemically bonded rare earth light conversion film; Preferably, in the multi-layer structure, other functional layers are further included.

10. Application of the chemically bonded rare earth light conversion film according to claim 8 or 9 in agricultural films, photovoltaic films or soft light bioreactors.

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