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 with 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, a ligand in the rare earth light conversion material comprises a photoreaction ligand; 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 problems that in the prior art, the chemical bonding type rare earth light conversion film preparation process is complex in chemical process, strict in reaction condition requirement, high in operation cost, low in applicability and the like can be solved, the method is simple, the migration, agglomeration and overflow phenomena of the rare earth light conversion material in the light conversion film can be greatly reduced, and the light conversion efficiency is improved. And the light conversion service life of the light conversion film can be greatly prolonged.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation of rare earth light conversion films, 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, including agricultural films, encapsulation adhesive films for solar cells, and materials for photobioreactors.

[0003] Currently, rare earth light conversion films are mainly prepared by adding 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, or in other words, there is no chemical bond combination, including methods such as adsorption dyeing and masterbatch blending. Currently, in the agricultural field, introducing rare earth light conversion materials into film materials mainly uses physical mixing methods. For example, CN102634102A discloses a method for preparing a multifunctional light conversion film with added rare earths, including: mixing LDPE, rare earth light conversion agent, anti-aging agent, and anti-fogging agent, and extruding and granulating to obtain a masterbatch; mixing LDPE, LLDPE, mLLDPE, and the masterbatch, and extruding and blowing to obtain a finished product. This method is relatively simple and has low cost. However, since the rare earth light conversion material and the film material have a simple physical interaction and generally poor compatibility, during use, they will gradually precipitate or agglomerate, resulting in a decrease in uniformity and light transmittance, and even causing fluorescence quenching, 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 synergistic effect of the 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 for 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 technology, the purpose of the present invention is to provide a chemically bonded rare earth light conversion film, a preparation method thereof and an application. The preparation method of the chemically bonded rare earth light conversion film provided by the present invention solves the problems in the prior art, such as complex chemical processes, strict reaction conditions, high operating costs, and poor applicability during the preparation of the chemically bonded rare earth light conversion film. The method is simple, can greatly reduce the migration, aggregation and overflow of rare earth light conversion materials in the light conversion film, and can greatly improve the light conversion life of the light conversion film.

[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 the rare earth light conversion material with the 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 the matrix resin to obtain the chemically bonded rare earth light conversion film; the ligand in the rare earth light conversion material includes a photoreactive ligand; in at least one of step (1) and step (2), after the extrusion, there is also a step of ultraviolet light irradiation.

[0011] In the present invention, by using a rare earth light conversion material containing a photoreactive ligand and under ultraviolet light irradiation, a chemically bonded rare earth light conversion film can be directly prepared, avoiding the problem of poor solubility of the complex caused by the method 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 film has a higher life.

[0012] Preferably, the molecular formula of the rare earth light conversion material is REA x B y R z ; wherein, RE is a rare earth central ion, A is a rigid ligand, B is a flexible ligand, and R is a photoreactive ligand; x≥0, for example, it can be 0, 1, 2, 3, 4, 5, 6, 7, 8, etc.; y≥0, for example, it can be 0, 1, 2, 3, 4, 5, 6, 7, 8, etc.; z≥1, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, etc.

[0013] Preferably, the rare earth central ion includes Eu 3+ , Tb 3+ , Sm 3+ , Dy 3+ , Nd 3+ , Ho 3+ , Er 3+ , Tm 3+ , Pr3+ , Eu 2 + , Yb 2+ or Sm 2+ or at least one of them.

[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, amino, or halogen.

[0015] Preferably, the flexible ligand includes at least one of 2-thenoyltrifluoroacetone, acetylacetone, hexafluoroacetylacetone, benzoyltrifluoroacetone, 5-sulfosalicylic acid, 6-methyl-2-pyridinecarboxylic acid, benzoic acid, p-benzoic acid, acrylic acid, and methacrylic acid.

[0016] Preferably, the rigid ligand includes at least one of substituted or unsubstituted C6-C30 aryl ring ligands and substituted or unsubstituted C5-C30 heteroaryl ring ligands; the substituents of the substitution include at least one of carboxyl, sulfonic acid group, hydroxyl, amino, or halogen.

[0017] 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.

[0018] Preferably, the rigid ligand includes at least one of o-phenanthroline, 2,2'-bipyridine, 8-hydroxyquinoline, triphenylphosphine oxide, 2,2':6',2”-terpyridine, salicylic acid, cinnamic acid, nicotinic acid, and naphthalenetetracarboxylic acid.

[0019] In the present invention, the photoreactive ligand includes at least one of benzophenone ligands, α-arylvinyl azide compounds, or vinyl azide compounds.

[0020] In the present invention, the photoreactive ligand includes at least one of o-benzoylbenzoic acid, 2,4-dihydroxybenzophenone, 4-allyloxy-2-hydroxybenzophenone, 2-hydroxy-4-acryloyloxybenzophenone, dibenzoylmethane, 2-hydroxy-4-(methacryloyloxy)benzophenone, 3-isopentenyl-2,4,6-trihydroxybenzophenone, sodium 4,4'-diazodistyrene-2,2'-disulfonate, α-arylvinyl azide, vinyl azide compound, 2,2'-dihydroxybenzophenone, 2-hydroxy-5-chlorobenzophenone, 2,3,4-trihydroxybenzophenone, phenyl salicylate (salol), 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-(2'-hydroxy-3',5'-di-tert-phenyl)-5-chlorobenzotriazole.

[0021] Preferably, the intensity of the ultraviolet light irradiation is independently 10 - 4000 mW / cm 2 , for example, it can 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 / cm 2 , 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 / cm2 、 4000 mW / cm 2 etc.

[0022] Preferably, the time of the ultraviolet light irradiation is 0.1 s to 15 min, and for example, it can be 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, it is 1 s to 5 min.

[0023] In the present invention, when the time of the ultraviolet light irradiation is within the above-defined range, the light conversion effect of the obtained material is better; if the time is too short or the intensity is too low, the input energy cannot cause the photoinitiator to 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 cause a decline in related properties.

[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 masterbatch resin and the matrix resin each independently include 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).

[0026] In the present invention, the thermoplastic elastomer includes TPU elastomer, TPO elastomer, TPE elastomer or TPEE elastomer, etc.

[0027] 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.

[0028] Preferably, the mixed materials in step (1) further include a crosslinking agent, which is a compound containing at least two unsaturated double bonds. The at least two unsaturated double bonds can be, for example, 2, 3, 4, 5, 6, etc.

[0029] Preferably, the crosslinking agent includes at least one of dicumyl peroxide, di-tert-butyl peroxyisopropylbenzene, trihydroxypropane diallyl ether, ethylene glycol dimethacrylate, diethylene glycol divinyl ether, triallyl cyanurate, triallyl isocyanurate, trimethylolpropane triacrylate, or pentaerythritol tetraallyl ether.

[0030] Preferably, the mass percentage content of the crosslinking agent is 0.01% to 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%, 0.3%, 0.5%, 0.7%, 0.9%, 1%, 1.3%, 1.5%, 1.7%, 1.9%, 2%, 2.2%, 2.4%, 2.6%, 2.7%, 3%, 3.3%, 3.6%, 3.9%, 4%, 4.2%, 4.4%, 4.5%, 4.7%, 4.9%, 5%, etc.

[0031] Preferably, the mass ratio of the rare earth light conversion masterbatch to the matrix resin in step (2) is (1 to 30):(40 to 99), where the specific values in (1 to 30) can be, for example, 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc., and the specific values in (40 to 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.

[0032] Preferably, the mixed materials in step (2) include additives.

[0033] Preferably, the mass ratio of the additives to the matrix resin is (1 to 30):(40 to 98), where the specific values in (1 to 30) can be, for example, 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, etc.; the specific values in (40 to 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.

[0034] Preferably, the auxiliary agent is obtained by mixing and extruding a first auxiliary agent and a first resin.

[0035] In the present invention, the temperature for mixing the first auxiliary agent and the first resin is 25 - 400 °C, and the time is 1 s - 90 min; the temperature for extrusion is 80 - 400 °C.

[0036] Preferably, the mass ratio of the first auxiliary agent to the first resin is (0.1 - 30):(40 - 99.9); specifically, the 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 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.

[0037] Preferably, the first auxiliary agent 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.

[0038] 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.

[0039] Preferably, the temperature for the mixing in step (1) and step (2) is independently 25 - 400 °C, for example, 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 time for the mixing is independently 1 s - 90 min, for example, 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.

[0040] In the present invention, the equipment for mixing includes, but is not limited to, a magnetic stirrer, a mechanical stirrer, a kneader, a high - speed mixer, a sand mill, an open mill, an internal mixer, or a twin - screw extruder, etc.

[0041] Preferably, the temperatures of the extrusion in steps (1) and (2) are each independently 80 to 400 °C, and can be, for example, 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.

[0042] 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 vulcanizing machines, 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.

[0043] As a preferred technical solution of the present invention, the preparation method includes the following steps:

[0044] (1) Mix the rare earth light conversion material, the masterbatch resin, and optionally the cross-linking agent at 25 to 400 °C for 1 s to 90 min, then extrude at 80 to 400 °C, and 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;

[0045] (2) Mix the chemically bonded rare earth light conversion masterbatch obtained in step (1), the matrix resin, and optionally the additives at 25 to 400 °C for 1 s to 90 min, then extrude at 80 to 400 °C to obtain the chemically bonded rare earth light conversion film;

[0046] Or

[0047] (11) Mix the rare earth light conversion material, the masterbatch resin, and optionally the cross-linking agent at 25 to 400 °C for 1 s to 90 min, then extrude at 80 to 400 °C to obtain a physically blended rare earth light conversion masterbatch;

[0048] (12) Mix the physically blended rare earth light conversion masterbatch obtained in step (11), the matrix resin, and optionally the additives at 25 to 400 °C for 1 s to 90 min, then extrude at 80 to 400 °C, and irradiate with ultraviolet light having an intensity of 10 to 4000 mW / cm 2 for 0.1 s to 15 min to obtain the chemically bonded rare earth light conversion film; the ligand in the rare earth light conversion material includes a photoreactive ligand.

[0049] In the present invention, in the preparation method, through physical mixing combined with ultraviolet irradiation, the masterbatch resin and the rare earth light conversion material are bonded together through chemical bonding, or the physically blended light conversion masterbatch and the matrix resin are chemically bonded, so as to avoid the precipitation or agglomeration of the rare earth light conversion material in the resin, resulting in a decrease in uniformity and light transmittance; moreover, 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.

[0050] In a 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.

[0051] Preferably, the chemically bonded rare earth light conversion film includes a single-layer structure or a multi-layer structure.

[0052] 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.

[0053] 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.

[0054] In the present invention, the single-layer structure means 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 means 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.

[0055] In the present invention, when the rare earth light conversion film is of a multi-layer structure, preferably the rare earth light conversion layer is located in the middle layer 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 improve the light conversion life of the rare earth light conversion film.

[0056] Preferably, in the multi-layer structure, it further includes other functional layers.

[0057] In the present invention, the other functional layers mean co-extruding the functional material with the material 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-resistant layer, a heat-insulating layer, an antistatic layer, a toughening layer, a water or gas barrier layer, etc.

[0058] In a third aspect, the present invention provides an application of the chemically bonded rare earth light conversion film according to the second aspect in an agricultural film, a photovoltaic film or a photobioreactor, preferably a flexible photobioreactor.

[0059] Preferably, the flexible photobioreactor is used for culturing microalgae or other photosynthetic microorganisms.

[0060] The numerical ranges described in the present invention include not only the above-listed point values, but also 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 described ranges.

[0061] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0062] In the present invention, by using a rare earth light conversion material containing a photoreactive ligand and simultaneously connecting the rare earth light conversion material with a resin through a chemical bond under ultraviolet light irradiation, a chemically bonded rare earth light conversion thin film is directly prepared. The process is simple and convenient, with low cost, reducing the migration, aggregation, and overflow phenomena of the rare earth light conversion material in the light conversion thin film, and can significantly improve the light conversion life of the light conversion thin film, making it suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 It is a flow chart of the preparation method of the chemically bonded rare earth light conversion thin film described in the present invention;

[0064] Among them, 1 is a schematic diagram of the preparation method flow provided in Example 1; 2 is a schematic diagram of the preparation method flow provided in Example 2;

[0065] Figure 2 It is an infrared spectrum diagram of the rare earth light conversion material described in Example 1;

[0066] Figure 3 It is a schematic diagram of the molecular structure of the rare earth light conversion material described in Example 1;

[0067] Figure 4 It is an excitation spectrum diagram of the rare earth light conversion material described in Example 1;

[0068] Figure 5 It is an emission spectrum diagram of the rare earth light conversion material described in Example 1;

[0069] Figure 6 It is a scanning electron microscope image of the chemically bonded rare earth light conversion thin film described in Example 1;

[0070] Figure 7 It is a comparison diagram of the emission spectra of the chemically bonded rare earth light conversion thin film described in Example 1 and the rare earth light conversion thin film described in Comparative Example 1 before and after the aging test;

[0071] Figure 8 It is a comparison diagram of the excitation spectra of the chemically bonded rare earth light conversion thin film described in Example 1 and the rare earth light conversion thin film described in Comparative Example 1 before and after the aging test. DETAILED DESCRIPTION OF THE INVENTION

[0072] The technical solution 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 on the present invention.

[0073] Example 1

[0074] This example provides a preparation method of a chemically bonded rare earth light conversion film, which specifically includes the following steps:

[0075] (1) 6 parts of rare earth light conversion material (Eu(TTA) 2 PhenR 1 , where R 1 is the photoreactive ligand benzoyl benzoate) and 94 parts of ethylene-vinyl acetate resin (ExxonMobil EscoreneTM Ultra LD 708.NM) are added to a high-speed mixer and mixed at 80 °C for 30 min. Then, melt, knead, extrude, cool, and pelletize using a twin-screw extruder. The relevant parameters of the twin-screw extruder are set as follows: the barrel zone 1 of main machines A, B, and C is 180 °C, the barrel zone 2 is 185 °C, the barrel zone 3 is 195 °C, the transition zone is 205 °C, and the temperature of the die head zone is set as: the die head zone 1 is 175 °C, the die head zone 2 is 180 °C, and the die head zone 3 is 190 °C. The speed of the main machines is all set to 50 rpm. At the same time, the extruded material is irradiated with ultraviolet light with an intensity of 1000 mW / cm 2 for 10 s to obtain a chemically bonded rare earth light conversion masterbatch.

[0076] (2) EVA resin (ExxonMobil EscoreneTM Ultra LD 708.NM), chemically bonded rare earth light conversion masterbatch, and additives are mixed evenly at room temperature in a mass ratio of 90:5:5, and then formed by extrusion blow molding using a single-screw extruder. Set the barrel temperature of the single-screw extruder to 175 °C and the head temperature to 200 °C. After melting and extruding through the extruder, it enters the die head to form a film extrusion. Compressed air is blown into the film from the cooling air duct in the center of the die head to blow the film into a tubular film. After internal and external air cooling, the air in the film bubble is drained by the chevron board, and then it is drawn and wound to obtain the chemically bonded rare earth light conversion film; the additive is prepared by mixing an ultraviolet absorber UV531 and ethylene-vinyl acetate copolymer with a mass percentage of 10:90 evenly using a high-speed mixer at 80 °C, and then extruding and pelletizing at 200 °C.

[0077] In the present invention, the infrared spectrum of the light conversion material is as Figure 2 shown, the structural formula is as Figure 3 shown, the excitation spectrum is as Figure 4 shown, and the emission spectrum is as Figure 5As shown, the scanning electron microscope image of the chemically bonded rare earth light conversion film prepared in Example 1 is as Figure 6 shown, and the emission spectra and excitation spectra of the chemically bonded rare earth light conversion film prepared in Example 1 before and after the aging test are respectively as Figure 7 , Figure 8 shown.

[0078] Example 2

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

[0080] (1) Add 7 parts of rare earth light conversion material (Eu(TTA) 2 PhenR 2 , where R 2 is the photoreactive ligand 2-4-dihydroxybenzophenone) and 93 parts of EVA resin into a kneader and mix at 50 °C for 40 min. Use a twin-screw extruder for melting, mixing, extrusion molding, cooling, and pelletizing to obtain a physically blended light conversion masterbatch; the relevant parameter settings of the twin-screw extruder are the same as those in Example 1.

[0081] (2) Mix the physically blended light conversion masterbatch obtained in step (1) with EVA resin and additives in a mass ratio of 91:4:5 evenly at room temperature, and then use a single-screw extruder to form by extrusion blow molding. Set the barrel temperature of the single-screw extruder to 165 °C and the head temperature to 190 °C. After melting and extruding through the extruder, it enters the die head to form a film extrusion. Compressed air is blown in from the cooling air duct in the center of the die head to blow the film into a tubular film. After internal and external air cooling, the herringbone splint drains the air in the film bubble, and then it is drawn and wound to obtain a film. Irradiate the film with ultraviolet light with an intensity of 1000 mW / cm 2 for 10 s to obtain the chemically bonded rare earth light conversion film; the additive is obtained by mixing a nucleating agent TMY-4 and ethylene-vinyl acetate copolymer in a mass ratio of 5:95 evenly in a kneader at 80 °C, and then extruding and molding at 150 °C and pelletizing.

[0082] Example 3

[0083] This example provides a method for preparing the chemically bonded rare earth light conversion film, and the specific steps include:

[0084] (1) Add 5 parts of rare earth light conversion material (Eu(TTA) 2 PhenR 3 , where, R 36 parts of rare earth light conversion material (Eu(TTA) 2 PhenR

[0085] , where R

[0086] is the photo-reactive ligand dibenzoylmethane), and 94 parts of ethylene-vinyl acetate resin are mixed in a kneader at 120 °C for 10 min, and then melted, kneaded, extruded, cooled, and pelletized using a twin-screw extruder. The relevant parameter settings of the twin-screw extruder are the same as those in Example 1 to obtain a physically blended light conversion masterbatch.

[0087] Example 4

[0088] (1) 6 parts of rare earth light conversion material (Eu(TTA) 2 PhenR 4 , where R 4 is the photo-reactive ligand dibenzoylmethane), and 94 parts of ethylene-vinyl acetate resin are mixed in a kneader at 120 °C for 10 min, and then melted, kneaded, extruded, cooled, and pelletized using a twin-screw extruder. The relevant parameter settings of the twin-screw extruder are the same as those in Example 1 to obtain a physically blended light conversion masterbatch.

[0089] (2) Mix the inner layer material, rare earth light conversion intermediate layer material, second functional layer material, and outer layer material evenly at 90 °C, and then use a multi-layer co-extrusion extruder to form by extrusion blow molding. Set the barrel temperature of the single-screw extruder to 195 °C and the head temperature to 220 °C. After melting and extruding through the extruder, it enters the die head to form a film extrusion. Compressed air is blown into the film from the cooling air duct in the center of the die head to blow the film into a tubular film. After internal and external air cooling, the herringbone splint drains the air in the film bubble, and then it is drawn and wound to obtain a film. Irradiate the film under ultraviolet light with an intensity of 1000 mW / cm 2 for 20 s to obtain the chemically bonded rare earth light conversion film with a multi-layer structure (i.e., including an inner layer, a rare earth light conversion intermediate layer, a second functional layer, and an outer layer); 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 additive with a mass ratio of 75:15:10 (the nucleating agent TMY-4A and PE resin with a mass ratio of 2:98 are mixed evenly at 80 °C, and then extruded and formed 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 with 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 indium tin oxide.

[0090] Example 5

[0091] This example provides a preparation method of a chemically bonded rare earth light conversion film, which is only different from Example 1 in that in the preparation method, the raw materials in step (1) include a rare earth light conversion material (Eu(TTA) 3 R 5 , where R 5 is a photoreactive ligand 2,2'-dihydroxybenzophenone) and low-density polyethylene (grade ExxonMobilExxonMobil TM LDPE LD 136.MN) with a mass ratio of 10:85; irradiate under ultraviolet light with an intensity of 600 mW / cm 2 for 120 s; the raw materials in step (2) include low-density polyethylene, chemically bonded light conversion masterbatch, and an additive with a mass ratio of 89:10:1, and other steps and parameters are the same as those in Example 1.

[0092] Example 6

[0093] This example provides a preparation method of a chemically bonded rare earth light conversion film, which is only different from Example 1 in that in the preparation method, the raw materials in step (1) include a rare earth light conversion material (Sm(Sal) 3 R 6 , where R6 The photo-reactive ligand is 2-hydroxy-5-chlorobenzophenone), and the polypropylene is (Kaijie Plastics); irradiated under ultraviolet light with an intensity of 1200 mW / cm 2 for 8 s; The preparation raw materials in step (2) include polypropylene, chemically bonded light conversion masterbatch and additives with a mass ratio of 94:5:1, and other steps and parameters are the same as those in Example 1.

[0094] Example 7

[0095] This example provides a method for preparing a chemically bonded rare earth light conversion film. The difference from Example 1 is only that in the preparation raw materials of the chemically bonded light conversion masterbatch, the total amount of the rare earth light conversion material and the EVA resin remains unchanged, and the mass ratio is 22:78. Other materials, structures and preparation methods are the same as those in Example 1.

[0096] Example 8

[0097] This example provides a rare earth light conversion film. The difference from 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 Example 1.

[0098] Example 9

[0099] This example provides a chemically bonded rare earth light conversion film. The difference from Example 1 is only that in the preparation method, the irradiation intensity in step (1) is 500 mW / cm 2 , and other materials, structures and preparation methods are the same as those in Example 1.

[0100] Example 10

[0101] This example provides a chemically bonded rare earth light conversion film. The difference from Example 1 is only that in the preparation method, the irradiation intensity in step (1) is 1500 mW / cm 2 , and other materials, structures and preparation methods are the same as those in Example 1.

[0102] Example 11

[0103] This example provides a chemically bonded rare earth light conversion film. The difference from Example 1 is only that in the preparation method, the irradiation intensity in step (1) is 150 mW / cm 2 , and other materials, structures and preparation methods are the same as those in Example 1.

[0104] Example 12

[0105] This example provides a chemically bonded rare earth light conversion film. The difference from Example 1 is only that in the preparation method, the irradiation intensity in step (1) is 3800 mW / cm2 , and the other materials, structures and preparation methods are the same as those in Example 1.

[0106] Example 13

[0107] This comparative example provides a method for preparing a rare earth light conversion film, which is different from Example 1 only in that the raw materials for preparing the chemical-bonded rare earth light conversion masterbatch further include 0.1 part of crosslinking agent triallyl cyanurate. The other materials, structures and preparation methods are the same as those in Example 1.

[0108] Comparative Example 1

[0109] This comparative example provides a method for preparing a rare earth light conversion film, which is different from Example 1 only in that in the preparation method, ultraviolet light irradiation is not carried out in step (1), and the other materials, structures and preparation methods are the same as those in Example 1.

[0110] Performance Test

[0111] Leaching 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 until constant weight to 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 Eu in the solution with a flame element absorption spectrometer, and calculate the retention rate of the light conversion agent in each film. The calculation formula is:

[0112]

[0113] where 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, %.

[0114] The specific test results are shown in Table 1.

[0115] Aging performance: Cut the film into 6 × 10 cm and put it into a mold, and then put it into an ultraviolet aging box. Set the aging program according to GB / T 14522-2008 (8 h of drying (0.76 W / (m 2·nm)), 50 °C; 0.25 h spray; 3.75 h condensation, 50 °C). After 15 days of aging, the film was taken out, cut into 1×5 cm size for the measurement of light conversion performance. There were three parallel samples for each sample. The retention rate of fluorescence emission intensity of the rare earth light conversion film after aging was calculated by the following formula; the test results are shown in Table 1.

[0116]

[0117] Among them, 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.

[0118] In the present invention, the test conditions for the light conversion performance are as follows: the test slit is 0.2 nm, the step is 1, the interval is 0.2 s, excitation spectrum test: scanning range: 200 - 500 nm, excitation peak: 389 nm; emission spectrum test: scanning range: 400 - 800 nm, the slit width is set to 0.3 nm, the step is set to 1, the scanning interval is 0.2 s, emission peak: 612 nm.

[0119] Table 1

[0120]

[0121]

[0122] As can be seen from the above table, the chemically bonded rare earth light conversion film provided by the present invention does not need to adopt the polymerization method. By using the rare earth light conversion material containing photoreactive ligands and under ultraviolet light irradiation, the chemically bonded rare earth light conversion film can be directly prepared, avoiding the problem that the complex is difficult to dissolve caused by the method of first polymerizing and then coordinating or first coordinating and then polymerizing in the prior art. The process is simple and convenient, and the obtained chemically bonded rare earth light conversion film has a higher lifespan and better aging resistance.

[0123] The applicant declares that the above description is only the specific implementation manner 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 with 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 ligand in the rare earth light conversion material comprises a photoreactive ligand; 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 is REA x B y R z ; where RE is a rare earth central ion, A is a rigid ligand, B is a flexible ligand, and R is a photoreactive ligand; x≥0, y≥0, z≥1; 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 comprises at least one of a thioether ligand, a β-diketone ligand, a 4-hydroxy-1,5-naphthyridine ligand, an aromatic heterocyclic carboxylic acid ligand, a substituted or unsubstituted C4-C20 alkyl ligand; the substituent of the substitution comprises at least one of a carboxyl group, a sulfonic acid group, a hydroxyl group, an amino group or a halogen; preferably, the rigid ligand comprises at least one of a substituted or unsubstituted C6-C30 aromatic ring ligand, a substituted or unsubstituted C5-C30 heteroaromatic ring ligand; the substituent of the substitution comprises at least one of a carboxyl group, a sulfonic acid group, a hydroxyl group, an amino group or a halogen; preferably, the photoreactive ligand comprises at least one of a benzophenone ligand, an α-arylvinyl azide compound or a vinyl azide compound.

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; more preferably 1 s to 5 min.

4. The preparation method according to any one of claims 1 to 3, characterized in that, the masterbatch resin and the matrix resin each independently comprise 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; 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 comprise a crosslinking agent, and the crosslinking agent is a compound containing at least 2 unsaturated double bonds; preferably, the crosslinking agent comprises at least one of dicumyl peroxide, di-tert-butyl peroxyisopropylbenzene, 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% to 5%.

5. 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 comprise 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 auxiliary agent 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, an antistatic agent, 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. According to the preparation method described in claim 5, wherein, the temperature of the mixing in step (1) and step (2) is independently 25-400°C, and the mixing time is independently 1 s-90 min; Preferably, the temperature of the extrusion in step (1) and step (2) is independently 80-400°C.

7. A preparation method according to any one of claims 1-6, wherein, the preparation method includes the following steps: (1) Mix the rare earth light conversion material, the masterbatch resin and an optional crosslinking agent at 25 - 400 °C for 1 s - 90 min, then extrude at 80 - 400 °C, and irradiate with ultraviolet light with an intensity of 10 - 4000 mW / cm 2 for 0.1 s - 15 min to obtain a chemically bonded rare earth light conversion masterbatch; (2) Mix the chemically bonded rare earth photoluminescent masterbatch obtained in step (1) with the matrix resin and an optional auxiliary agent at 25-400°C for 1 s-90 min, and then extrude at 80-400°C to obtain the chemically bonded rare earth photoluminescent film; or (11) Mix the rare earth photoluminescent material with the masterbatch resin and an 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 photoluminescent 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 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 ligand in the rare earth photoluminescent material includes a photoreactive ligand.

8. A chemically bonded rare earth photoluminescent film, wherein, the chemically bonded rare earth photoluminescent film is prepared by the preparation method according to any one of claims 1-7.

9. According to the chemically bonded rare earth photoluminescent film described in claim 8, wherein, the chemically bonded rare earth photoluminescent 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 photoluminescent layer; the rare earth photoluminescent layer is the chemically bonded rare earth photoluminescent film; Preferably, in the multi-layer structure, other functional layers are further included.

10. An application of the chemically bonded rare earth photoluminescent film according to claim 8 or 9 in an agricultural film, a photovoltaic film, or a soft photobioreactor.

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