阅读说明：本技术 树脂封装材料及qled器件的制备方法 (Resin packaging material and preparation method of QLED device ) 是由 完亮亮 龙能文 骆意勇 于 2020-06-19 设计创作，主要内容包括：本申请提供一种树脂封装材料及QLED器件的制备方法,属于封装材料领域。树脂封装材料的制备方法包括：将环氧树脂采用氟化物质进行改性处理,得到氟改性体系；将所述氟改性体系和二聚酸在85～95℃的条件下进行第一反应,使得所述氟改性体系的部分环氧基参与反应,得到环氧中间体系；将所述环氧中间体系和丙烯酸在100～110℃的条件下进行第二反应。QLED器件的制备方法包括采用该树脂封装材料的制备方法制备树脂封装材料。制得的树脂封装材料具有良好的水氧隔离效果和韧性,对QLED器件具有良好的保护效果,能有效提升QLED器件的使用寿命。(The application provides a resin packaging material and a preparation method of a QLED device, and belongs to the field of packaging materials. The preparation method of the resin packaging material comprises the following steps: modifying the epoxy resin by adopting a fluorinated substance to obtain a fluorine modified system; carrying out a first reaction on the fluorine modified system and dimer acid at 85-95 ℃ so as to allow part of epoxy groups of the fluorine modified system to participate in the reaction and obtain an epoxy intermediate system; and carrying out a second reaction on the epoxy intermediate system and acrylic acid at the temperature of 100-110 ℃. The preparation method of the QLED device comprises the step of preparing the resin packaging material by adopting the preparation method of the resin packaging material. The prepared resin packaging material has good water-oxygen isolation effect and toughness, has good protection effect on the QLED device, and can effectively prolong the service life of the QLED device.)

1. A method for preparing a resin encapsulating material, comprising:

modifying the epoxy resin by adopting a fluorinated substance to obtain a fluorine modified system;

carrying out a first reaction on the fluorine modified system and dimer acid at 85-95 ℃ so as to allow part of epoxy groups of the fluorine modified system to participate in the reaction and obtain an epoxy intermediate system;

and carrying out a second reaction on the epoxy intermediate system and acrylic acid at the temperature of 100-110 ℃.

2. The method of claim 1, further comprising, between the first reaction and the second reaction: and mixing the epoxy intermediate system and the acrylic acid for 40-80 min at the temperature of 85-95 ℃.

3. The method of claim 1, wherein the epoxy intermediate system and the acrylic acid are reacted in the presence of itaconic acid;

optionally, the molar ratio of the epoxy resin to the itaconic acid is 10: 3.5-4.5.

4. The preparation method according to claim 3, wherein the molar ratio of the epoxy resin to the dimer acid is 10: 1.5-2.5;

and/or the molar ratio of the epoxy resin to the acrylic acid is 10: 3.5-4.5.

5. The preparation method according to claim 1, wherein in the first reaction, the acid value of the system is detected every 12-18min, and the first reaction is finished when the acid value of the system is less than 3.5mg KOH/g;

and/or, the first reaction is carried out in the presence of a first catalyst.

6. The preparation method according to any one of claims 1 to 5, wherein the epoxy intermediate system and the acrylic acid are reacted in the presence of a cosolvent, a second catalyst and a polymerization inhibitor;

optionally, when the epoxy intermediate system reacts with the acrylic acid, the cosolvent, the second catalyst and the polymerization inhibitor are dropwise added into the epoxy intermediate system for reaction.

7. The method according to claim 6, wherein the acid value of the system is detected every 25 to 35min in the second reaction, and the second reaction is terminated when the acid value of the system is reduced to a predetermined value.

8. The method according to any one of claims 1 to 5, wherein the modification treatment comprises graft copolymerization of the epoxy resin and the fluorinated substance, optionally hexafluorobutyl methacrylate;

alternatively, the modification treatment comprises mixing the epoxy resin with the fluorinated substance, optionally at least one selected from the group consisting of polytetrafluoroethylene, fluorinated polyethylene and fluorocarbon wax.

9. The method according to any one of claims 1 to 5, wherein the second reaction further comprises: and cooling the system to 55-65 ℃, and then adjusting the pH value of the system to 6-7.

10. A method for manufacturing a QLED device, characterized in that a resin encapsulating material is manufactured by the manufacturing method as claimed in any one of claims 1 to 9.

Technical Field

The application relates to the field of packaging materials, in particular to a resin packaging material and a preparation method of a QLED device.

Background

The Light Emitting life of the QLED (quantum Dot Light Emitting diodes) device is greatly reduced by the influence of water and oxygen in the environment, and therefore, the packaging of the QLED device is very important. In the prior art, the QLED device is generally packaged by adopting UV resin, but the water-oxygen isolation effect of the UV resin cannot well meet the use requirement, so that the service life of the QLED device cannot meet the performance requirement.

Disclosure of Invention

The application aims to provide a resin packaging material and a preparation method of a QLED device, the prepared resin packaging material has good water-oxygen isolation effect and toughness, has a good protection effect on the QLED device, and can effectively prolong the service life of the QLED device.

The embodiment of the application is realized as follows:

in a first aspect, an embodiment of the present application provides a method for preparing a resin encapsulation material, including:

modifying the epoxy resin by adopting a fluorinated substance to obtain a fluorine modified system;

carrying out a first reaction on a fluorine modified system and dimer acid at 85-95 ℃ so that part of epoxy groups of the fluorine modified system participate in the reaction to obtain an epoxy intermediate system;

and carrying out a second reaction on the epoxy intermediate system and acrylic acid at the temperature of 100-110 ℃.

In a second aspect, an embodiment of the present application provides a method for manufacturing a QLED device, including: the resin encapsulating material is prepared by the preparation method provided by the embodiment of the first aspect.

The resin packaging material and the preparation method of the QLED device have the advantages that:

epoxy resin is modified by adopting fluorinated substances, and the fluorinated substances have excellent chemical corrosion resistance, weather resistance and hydrophobic and oleophobic properties, so that the hydrophobicity of the epoxy resin can be improved, and the prepared resin packaging material has a good water and oxygen isolation effect. Meanwhile, the fluorinated substance has better self-cleaning property and high light transmittance, and can better meet the performance requirement of the packaging material.

The inventor researches and discovers that the toughness of the epoxy resin is low, the thermal expansion coefficients of different materials in the QLED device are different, the stress generated between the functional layers is difficult to release, the problem of black spots is easy to generate, and the device fails.

The fluorine modified system and the dimer acid react, and the dimer acid contains chemically inert long alkane chains and alicyclic structures, so that the nonpolar alkane and alicyclic in the dimer acid are introduced into the crosslinking system, the toughness of the fluorine modified epoxy system can be improved, and the stress generated between functional layers can be well released by the prepared packaging material. Meanwhile, long alkyl side chains and alicyclic structures in the dimer acid have hydrophobicity, so that the balance water absorption of a fluorine modified epoxy system can be reduced, the diffusion coefficient of water molecules in the fluorine modified epoxy system is obviously reduced, and the water and oxygen isolation effect of the packaging material is obviously improved. In addition, the dimer acid is low in price, renewable and biodegradable, so that the packaging material is low in cost and good in environmental protection.

The dimer acid can well react with the epoxy group at 85-95 ℃ to generate an intermediate, and then the intermediate can well react with the epoxy group at 100-110 ℃; acrylic acid can react with the epoxy group well under the condition of 100-110 ℃. In the reaction process, the dimer acid and part of epoxy groups in the system are subjected to a first reaction at 85-95 ℃, and then the system and the acrylic acid are subjected to a reaction at 100-110 ℃, so that both the dimer acid and the acrylic acid can be controllably reacted with the epoxy groups in the system, and the reaction efficiency is high.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

It should be noted that "and/or" in the present application, such as "scheme a and/or scheme B" means that the three modes of scheme a alone, scheme B alone, scheme a plus scheme B may be used.

The following specifically describes a resin encapsulating material and a method for manufacturing a QLED device according to an embodiment of the present application.

In a first aspect, an application embodiment provides a method for preparing a resin encapsulation material, including:

s1, modifying epoxy resin by adopting a fluorinated substance to obtain a fluorine modified system.

The fluorinated substance has excellent chemical corrosion resistance, weather resistance, water and oil repellency, and can improve the hydrophobicity of the epoxy resin, so that the prepared resin packaging material has a good water and oxygen isolation effect. Meanwhile, the fluorinated substance has better self-cleaning property and high light transmittance, and can better meet the performance requirement of the packaging material.

It is understood that in the examples of the present application, the fluoride treatment to the epoxy resin may be a chemical treatment or a physical treatment. The kind of the fluorinated substance is not limited and may be selected according to the modification treatment.

Illustratively, the fluorinated substance is a fluorine-containing polymer, the fluorine atom has a small radius, extremely strong electronegativity and low polarizability, the bond energy of a C-F bond is high, and the fluorine-containing polymer has excellent chemical resistance, weather resistance and hydrophobic and oleophobic properties.

In some exemplary embodiments, the modification treatment includes graft copolymerization of an epoxy resin with a fluorinated species. Optionally, the fluorinated substance is hexafluorobutyl methacrylate, and researches show that when modification treatment is performed in a graft copolymerization mode, the controllability of the reaction of the fluorinated substance and the epoxy resin is good, and the resin is improved well after modification.

Exemplary methods for graft copolymerization of hexafluorobutyl methacrylate with epoxy resins include: dissolving epoxy resin in butyl acetate in a reflux reaction container with a stirrer, stirring and heating to 100-110 ℃, for example, stirring and heating to 100 ℃ so as to fully dissolve the epoxy resin. Keeping the heating temperature, mixing and dissolving hexafluorobutyl methacrylate, an initiator and a cosolvent, wherein the initiator is selected from one or at least two of dibenzoyl peroxide, 2-hydroxy-2-methyl-1-phenyl-1-acetone, benzophenone and 1-hydroxycyclohexyl phenyl ketone, such as 2-hydroxy-2-methyl-1-phenyl-1-acetone; the cosolvent is methyl methacrylate. Then dropwise adding into a reflux reaction vessel, wherein the dropwise adding operation is carried out by using a constant pressure funnel, the dropwise adding speed is 8-10 drops/min, and in the embodiment of the application, the volume of each drop is about 20 mu L. And after the dropwise addition is finished, continuously carrying out reflux reaction for 0.8-1.2h, for example, continuously carrying out reflux reaction for 1h to finish modification treatment, thus obtaining the fluorine modified system containing the fluorine modified resin.

In other exemplary embodiments, the modification treatment includes mixing the epoxy resin with a fluorinated material, optionally, the fluorinated material is selected from at least one of polytetrafluoroethylene, fluorinated polyethylene and fluorocarbon wax, for example, any one of the fluorinated materials, and it has been found that the epoxy resin has good dispersibility and the resin has good improvement effect after modification when the modification treatment is performed in a mixing manner.

S2, carrying out a first reaction on the fluorine modification system and dimer acid at 85-95 ℃ so that part of epoxy groups of the fluorine modification system participate in the reaction to obtain an epoxy intermediate system.

And S3, carrying out a second reaction on the epoxy intermediate system and acrylic acid at the temperature of 100-110 ℃.

Due to the fact that the dimer acid contains chemically inert long alkane chains and alicyclic structures, the nonpolar alkanes and alicyclic structures in the dimer acid are introduced into a crosslinking system, the toughness of a fluorine modified epoxy system can be improved, stress generated among functional layers can be well released by the prepared packaging material, and the problem of black spots can be effectively avoided, so that failure of a device is caused. Meanwhile, long alkyl side chains and alicyclic structures in the dimer acid have hydrophobicity, so that the balance water absorption of a fluorine modified epoxy system can be reduced, the diffusion coefficient of water molecules in the fluorine modified epoxy system is obviously reduced, and the water and oxygen isolation effect of the packaging material is obviously improved. In addition, the dimer acid is low in price, renewable and biodegradable, so that the packaging material is low in cost and good in environmental protection.

Researches find that dimer acid can well react with epoxy groups at 85-95 ℃ to generate an intermediate, then the intermediate can well react with the epoxy groups at 100-110 ℃, and acrylic acid can well react with the epoxy groups at 100-110 ℃. In the embodiment of the application, the dimer acid and part of epoxy groups in the system are subjected to a first reaction at 85-95 ℃, and then the system and the acrylic acid are subjected to a reaction at 100-110 ℃, so that both the dimer acid and the acrylic acid can be controllably reacted with the epoxy groups in the system, and the reaction efficiency is high.

Illustratively, the temperature conditions of the first reaction are, for example, but not limited to, any one or a range between any two of 85 ℃, 90 ℃, and 95 ℃; the temperature condition of the second reaction is, for example, but not limited to, a range between any one or any two of 100 ℃, 105 ℃ and 110 ℃.

In some possible embodiments, between the first reaction and the second reaction, further comprising: mixing an epoxy intermediate system and acrylic acid at 85-95 ℃ for 40-80 min to fully mix the system, so as to prevent the generated resin component from being uneven to influence the packaging effect of the device; illustratively, the mixing temperature is maintained at the same temperature conditions as the first reaction for a time period, such as, but not limited to, any one of, or a range between any two of, 40min, 50min, 60min, 70min, and 80 min. Namely, in the reaction system of the epoxy intermediate system and the acrylic acid, the epoxy intermediate system and the acrylic acid are firstly mixed for 40-80 min under the condition of 85-95 ℃, and then the second reaction is carried out under the condition of 100-110 ℃.

Regarding the reaction of the fluorine modification system and dimer acid:

in some possible embodiments, the first reaction is carried out in the presence of a first catalyst, and the first catalyst is used for catalysis due to the chemical inertness of the long alkane chain and the alicyclic structure in the dimer acid, so that the reaction efficiency of the dimer acid and the fluorine modification system is improved.

Optionally, the first catalyst is selected from at least one of N, N-dimethylbenzylamine, tetrabutylammonium bromide, triphenylphosphine, and triethylamine. It was found that N, N-dimethylbenzylamine has the best catalytic effect, followed by tetrabutylammonium bromide, followed by triphenylphosphine, and then triethylamine.

Illustratively, when the fluorine modified system and the dimer acid are reacted, the dimer acid and the catalyst are mixed and then added into the fluorine modified system in a dropwise manner to participate in the reaction.

Further, in the first reaction, the acid value of the system is detected every 12-18min, for example every 15min, and the first reaction is ended when the acid value of the system is less than 3.5mg KOH/g, so that the dimer acid is ensured to fully participate in the reaction.

Regarding the reaction of the oxygen intermediate system with acrylic acid:

in some possible embodiments, the epoxy intermediate system and acrylic acid are reacted in the presence of a co-solvent, a second catalyst and a polymerization inhibitor, ensuring that the reaction can be carried out rapidly and controllably. Optionally, the cosolvent is methyl methacrylate; the second catalyst is p-toluenesulfonic acid; the polymerization inhibitor is hydroquinone.

Illustratively, when the epoxy intermediate system and acrylic acid are reacted, the acrylic acid, the cosolvent, the second catalyst and the polymerization inhibitor are added dropwise into the epoxy intermediate system to react. The dropping operation is, for example, to mix the raw materials and then to drop the raw materials by using a constant pressure funnel, wherein the dropping speed is, for example, 8 to 10 drops/s, so that the controllability of the reaction is better.

Further, in the second reaction, the acid value of the system is detected every 25-35min, for example every 30min, and the second reaction is ended when the acid value of the system is reduced to a preset value. The predetermined value is the theoretical acid number.

The acid value is the number of mg of KOH consumed for neutralizing 1g of acidic substance in the specimen. When determining the acid ester, accurately weighing 0.5-1.0g of a sample to be detected in a 250ml conical flask, adding 20ml of absolute ethyl alcohol or acetone to completely dissolve the sample, dropwise adding 2-4 drops of phenolphthalein indicator, and titrating with 0.1mol/L KOH-ethanol standard solution until the color is pink and does not fade for 30s, thus obtaining the titration end point. It is understood that, in the examples of the present application, the theoretical acid value means the theoretical value of the acid value of the solution after the reaction of the starting materials is assumed to be completed.

Researches show that epoxy resin is easy to yellow in use, and the problem of resin yellowing can be effectively improved by adding itaconic acid into the reaction system provided by the embodiment of the application. Moreover, the itaconic acid can improve the water solubility of the resin, so that the resin has better service performance.

In some possible embodiments, the epoxy intermediate system and acrylic acid are reacted in the presence of itaconic acid. Itaconic acid is added into the system to react with epoxy group, so that the problem of yellowing of the resin is effectively improved. Researches also find that itaconic acid can well react with an epoxy group at 100-110 ℃, itaconic acid is added to react with an epoxy intermediate system and acrylic acid, and the operation is convenient.

Illustratively, itaconic acid, when involved in the reaction of an epoxy intermediate system and acrylic acid, is added to the epoxy intermediate system first and then acrylic acid is added dropwise to the epoxy intermediate system.

Optionally, the molar ratio of epoxy resin to itaconic acid is 10:3.5 to 4.5, such as but not limited to any one of 10:3.5, 10:4 and 10:4.5 or a range between any two.

In embodiments where itaconic acid is added, optionally, the molar ratio of epoxy resin to dimer acid is 10:1.5 to 2.5, such as but not limited to any one of 10:1.5, 10:2, and 10:2.5 or a range between any two; the molar ratio of epoxy resin to acrylic acid is 10:3.5 to 4.5, such as but not limited to any one of 10:3.5, 10:4, and 10:4.5 or a range between any two. Illustratively, the molar ratio of the epoxy resin to the dimer acid to the acrylic acid to the itaconic acid is 10: 1.5-2.5: 3.5-4.5, for example 10:2:4:4, and the amount of groups introduced by the dimer acid to the acrylic acid to the itaconic acid is appropriate, so that the resin packaging material has good comprehensive performance.

Further, in embodiments where itaconic acid is not added, optionally, the molar ratio of epoxy resin to dimer acid is 10:1.5 to 2.5, such as but not limited to any one of 10:1.5, 10:2, and 10:2.5 or a range between any two; the molar ratio of epoxy resin to acrylic acid is 10:3.5 to 4.5, such as but not limited to any one of 10:3.5, 10:4, and 10:4.5 or a range between any two. Illustratively, the molar ratio of epoxy resin, dimer acid, and acrylic acid is, in order, 10:2: 4.

After the second reaction, in some possible embodiments, further comprising: cooling the system to 55-65 ℃, for example, to any one of 55 ℃, 60 ℃ and 65 ℃ or a range between any two of the two; and then neutralizing the system, and adjusting the pH value of the system to 6-7, for example, to any one of 6, 6.5 and 7 or a range between any two.

Further, after the neutralization is finished, adding distilled water, continuously stirring to uniformly distribute the distilled water to obtain the water-based resin packaging material, discharging and storing in a closed container for later use.

In a second aspect, an embodiment of the present application provides a method for manufacturing a QLED device, including: the resin packaging material is prepared by adopting the preparation method of the resin packaging material provided by the embodiment of the first aspect. The prepared epoxy resin has good water and oxygen isolation effect and toughness, has good protection effect on the QLED device, and can effectively prolong the service life of the QLED device.

Illustratively, the QLED device is a front bottom emission structure, and includes a body structure and an encapsulation structure encapsulating the body structure, where the material of the encapsulation structure is the resin encapsulation material prepared by the method for preparing the resin encapsulation material provided in the embodiment of the first aspect, and the body structure includes a transparent anode substrate, a hole injection layer, a hole transport layer, a quantum dot light emitting layer, an electron transport layer, a transition layer, and a metal cathode, which are sequentially disposed. Optionally, the electron transport layer is a layer structure deposited by nano metal oxide, the transition layer is a particle structure deposited by nano metal oxide, and the reflection of the cathode to visible light is not less than 98%.

The preparation method of the QLED device with the positive bottom emission structure comprises the following steps:

on a transparent anode substrate, a hole injection layer is deposited.

On the hole injection layer, a hole transport layer is deposited.

On the hole transport layer, a quantum dot light emitting layer is deposited.

And depositing a nano metal oxide electron transport layer on the quantum dot light emitting layer.

And depositing a transition layer of nano metal oxide particles on the electron transport layer.

A metal cathode is deposited on the transition layer.

The resin packaging material is prepared for packaging by adopting the preparation method of the resin packaging material provided by the embodiment of the first aspect.

The features and properties of the present application are described in further detail below with reference to examples.