Water-blocking film and preparation method thereof

Abstract

The invention relates to the technical field of polymer films, in particular to a water-blocking film and a preparation method thereof. Comprising a base film layer, an oxide waterproof layer and a polymer protection layer which are sequentially stacked, the polymer protection layer comprises resin, a curing agent, a coupling aid, a heat dissipation material, a phase change material and an antioxidant, and the mass ratio of the resin to the curing agent to the phase change material to the heat dissipation material to the coupling material to the antioxidant is 100: (0.3-2.0): (0.3-3): (5-15): (0.3-5): (0.3-2.4); the coupling auxiliary agent mainly plays a role in coupling with resin and a plating layer, and meanwhile reacts with water to play a role in consuming water vapor; the polymer protective layer plays a role in protecting the water-blocking layer and prevents the water-blocking layer from generating microscopic cracks and defects under the action of high temperature and high humidity, so that the reduction of water vapor transmittance is relieved; the heat dissipation material has the effects of dissipating heat, transferring heat and preventing the local temperature from being too high; and the resin and the curing agent are crosslinked to form a skeleton of the polymer protection layer.

Description

Technical Field

[0001] The invention relates to the technical field of polymer films, in particular to a water-blocking film and a preparation method thereof. Background Art

[0002] At present, the water barrier problem of thin film materials has become a hot topic in the industry, and has been applied more and more widely, such as in quantum dot display screens, OLED display devices, photovoltaic water barrier backplanes, photovoltaic frontplanes, etc. The general practice is to use magnetron sputtering or evaporation to coat a layer of inorganic oxide on substrates such as PET to reduce the water vapor transmission rate, but after wet heat aging, the water vapor transmission rate generally increases rapidly. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a water-blocking film and a preparation method thereof.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0005] A water-blocking film, comprising a base film layer, an oxide water-blocking layer and a polymer protective layer stacked in sequence, wherein the polymer protective layer comprises a resin, a curing agent, a coupling aid, a heat dissipation material, a phase change material and an antioxidant, wherein the mass ratio of the above substances is resin: curing agent: phase change material: heat dissipation material: coupling material: antioxidant = 100: (0.3-2.0): (0.3-3): (5-15): (0.3-5): (0.3-2.4).

[0006] The coupling agent mainly plays the role of coupling with the resin and the coating, and reacts with water to consume water vapor.

[0007] The polymer protective layer protects the water-blocking layer, preventing the water-blocking layer from generating microscopic cracks and defects under high temperature and high humidity, thereby alleviating the decrease in water vapor transmission rate.

[0008] The heat dissipation material plays the role of dissipating heat and preventing the local temperature from being too high.

[0009] The resin and curing agent form the skeleton of the polymer protective layer after cross-linking.

[0010] Furthermore, the resin is an acrylic resin or a polyurethane resin, and the curing agent is an isocyanate curing agent.

[0011] Furthermore, the base film layer is selected from one of PET, PI, and PP, and the thickness of the base film layer is 1.5-500 μm.

[0012] Furthermore, the oxide water-blocking layer comprises a silicon dioxide coating and an aluminum oxide coating, the thickness of the oxide water-blocking layer is 10-100 nm, and the thickness of the polymer protective layer is 0.1-3 μm.

[0013] Furthermore, the antioxidant is selected from at least one of phenol antioxidant 1010 and phosphate antioxidant 245, and the heat dissipation material is selected from one or both of graphite and boron nitride.

[0014] Further, the phase change material is selected from one or more of magnesium sulfate heptahydrate, sodium sulfite pentahydrate, barium hydroxide octahydrate, and aluminum nitrate nonahydrate, or a combination of one or more of magnesium sulfate heptahydrate, sodium sulfite pentahydrate, barium hydroxide octahydrate, and aluminum nitrate nonahydrate and phenylacetic acid.

[0015] Furthermore, the phase change material is a composition of magnesium sulfate heptahydrate and barium hydroxide octahydrate or magnesium sulfate heptahydrate and aluminum nitrate nonahydrate, wherein the mass ratio thereof is 1:1, or a composition of magnesium sulfate heptahydrate, barium hydroxide octahydrate and phenylacetic acid, wherein the addition amount of phenylacetic acid is 10-30%, and the mass ratio of magnesium sulfate heptahydrate to barium hydroxide octahydrate is 1:1.

[0016] Furthermore, the coupling aid is selected from one or more of ethoxysilane oligomers, methoxysilane oligomers, and aluminum acetylacetonate.

[0017] A method for preparing a water-blocking film, the method comprising the following steps:

[0018] S1 Preparation of polymer protective layer coating liquid: gradually add curing agent, coupling agent, heat dissipation material, phase change material and antioxidant to acrylic resin according to proportion, stir evenly and set aside;

[0019] S2: coating the coating liquid prepared in step S1 onto the substrate coated with the oxide water-blocking layer through a wire rod, and first curing and then aging to obtain the water-blocking film.

[0020] Furthermore, the curing temperature is 110-130° C., the curing time is 1-5 minutes, the aging temperature is 30-50° C., and the aging time is 72-96 hours.

[0021] The beneficial effects of the technical solution of the present invention are:

[0022] The coupling aid in the present invention mainly plays the role of coupling with the resin and the coating, and reacts with water to consume water vapor; the polymer protective layer plays the role of protecting the water barrier layer, preventing the water barrier layer from generating micro cracks and defects under high temperature and high humidity, thereby alleviating the decrease in water vapor transmission rate; the heat dissipation material plays the role of heat dissipation and heat transfer, and preventing the local temperature from being too high; the resin and the curing agent form the skeleton of the polymer protective layer after cross-linking.

[0023] The silane oligomer added in the present invention can not only react with water to consume moisture, but also combine with the aluminum oxide coating, so the water vapor permeability can be reduced. At the same time, methyl silane oligomers (high reaction activity with water) and ethyl silane oligomers (low reaction activity with water, which can protect the coating more permanently) have better effects. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with specific implementation modes.

[0025] Example 1

[0026] The water-blocking film in the present invention comprises a base film layer, an oxide water-blocking layer and a polymer protective layer which are stacked in sequence, and the polymer protective layer comprises a resin, a curing agent, a coupling aid, a heat dissipation material, a phase change material and an antioxidant, and the mass ratio of the above substances is resin: curing agent: phase change material: heat dissipation material: coupling material: antioxidant = 100: (0.3-2.0): (0.3-3): (5-15): (0.3-5): (0.3-2.4).

[0027] The coupling agent mainly plays the role of coupling with the resin and the coating, and reacts with water to consume water vapor.

[0028] The polymer protective layer protects the water-blocking layer, preventing the water-blocking layer from generating microscopic cracks and defects under high temperature and high humidity, thereby alleviating the decrease in water vapor transmission rate.

[0029] The heat dissipation material plays the role of dissipating heat and preventing the local temperature from being too high.

[0030] The resin and curing agent form the skeleton of the polymer protective layer after cross-linking.

[0031] The resin is acrylic resin or polyurethane resin, and the curing agent is isocyanate curing agent.

[0032] Wherein, the base film layer is selected from one of PET, PI and PP, and the thickness of the base film layer is 1.5-500 μm.

[0033] The oxide water-blocking layer includes a silicon dioxide coating and an aluminum oxide coating, the thickness of the oxide water-blocking layer is 10-100 nm, and the thickness of the polymer protective layer is 0.1-3 μm.

[0034] The antioxidant is selected from at least one of phenol antioxidant 1010 and phosphate antioxidant 245, and the heat dissipation material is selected from one or both of graphite and boron nitride.

[0035] The phase change material is selected from one or more of magnesium sulfate heptahydrate, sodium sulfite pentahydrate, barium hydroxide octahydrate, and aluminum nitrate nonahydrate, or a combination of one or more of magnesium sulfate heptahydrate, sodium sulfite pentahydrate, barium hydroxide octahydrate, and aluminum nitrate nonahydrate and phenylacetic acid.

[0036] Among them, the phase change material is a combination of magnesium sulfate heptahydrate and barium hydroxide octahydrate or magnesium sulfate heptahydrate and aluminum nitrate nonahydrate, and the mass ratio thereof is 1:1, or a combination of magnesium sulfate heptahydrate, barium hydroxide octahydrate and phenylacetic acid, wherein the addition amount of phenylacetic acid is 10-30%, and the mass ratio of magnesium sulfate heptahydrate to barium hydroxide octahydrate is 1:1.

[0037] The coupling aid is selected from one or more of ethoxysilane oligomers, methoxysilane oligomers, and aluminum acetylacetonate.

[0038] The silane oligomer in the present invention comes from Shandong Si Ke Company, the curing agent is Bayer L-75, and the antioxidant comes from Beijing Additive Additive Company.

[0039] A method for preparing a water-blocking film comprises the following steps:

[0040] S1 Preparation of polymer protective layer coating liquid: gradually add curing agent, coupling agent, heat dissipation material, phase change material and antioxidant to acrylic resin in proportion, stir evenly and set aside, wherein the amount of acrylic resin is 100 parts, and the curing agent is isocyanate N3390, the proportion is 1 part;

[0041] S2: coating the coating liquid prepared in step S1 onto the substrate coated with the oxide water-blocking layer through a wire rod, first curing and then aging to obtain the water-blocking film, the curing temperature is 120° C., the curing time is 2 minutes, the aging temperature is 40° C., and the aging time is 72 hours.

[0042] The specific selection of each substance, the amount of addition, the initial water vapor transmission rate and the water vapor transmission rate of double 85 aging are shown in the examples.

[0043] Table 1, where the initial water vapor transmission rate is 0.05 (g / m 2 ·day).

[0044]

[0045]

[0046] Table 1

[0047] As can be seen from the above embodiments, the heat dissipation material can reduce the aging water vapor transmission rate. Due to its phase change heat absorption, it can reduce the heat borne by the aluminum oxide coating. However, when the addition amount reaches 5 parts, the water vapor transmission rate increases slightly. It should be because the phase change material changes from solid to liquid under heating conditions, which reduces the bonding force between the polymer protective layer and the water-blocking coating. The heat dissipation material can significantly reduce the water vapor transmission rate after aging, because the heat dissipation material can quickly conduct heat to prevent local overheating from causing micro cracking of the water-blocking layer, and the two materials, graphite (horizontal heat transfer) and boron nitride (vertical heat transfer), have a better combination effect, but too much heat dissipation material will also affect the bonding force between the resin and the water-blocking layer, so when the graphite is added to 20 parts, the water vapor transmission rate does not decrease. Aluminum acetylacetonate can absorb moisture and can be complexed with the water-blocking layer, which can reduce the water vapor transmission rate, but too much water absorption will affect the adhesion between the polymer protective layer and the coating, so when added to 2.0 parts, the water vapor transmission rate increases slightly. Silane oligomers can not only react with water and consume water, but also combine with the aluminum oxide coating, so they can reduce the water vapor transmission rate. At the same time, methyl silane oligomers (high water reaction activity) and ethyl silane oligomers (low water reaction activity, which can protect the coating more permanently) have better effects. However, after the silane polymer reacts with water, its silicon oxygen structure itself has a high water vapor transmission rate, so when the addition amount is 3 parts, the water vapor transmission rate is slightly improved. Antioxidants can resist thermal oxidation and provide protection for the polymer protective layer itself to prevent the main polymer chain from breaking during hydrothermal aging, so they can also reduce the water vapor transmission rate after aging, and the synergistic effect of two different types of antioxidants (phenol antioxidant 1010 and phosphate antioxidant 245) is better.

[0048] Example 2

[0049] The formula ratio is as per row 33 of the above table, the phase change material composition is as shown in Table 2 and Table 3, and the double 85 aging adhesion and double 85 aging water vapor transmission rate are tested.

[0050]

[0051] Table 2

[0052] From the data in Table 2, we can see that organic phase change materials become liquid due to solid-liquid phase change, which greatly destroys the adhesion and cannot be used alone. Inorganic phase change materials have little effect on water vapor transmission rate after aging. However, the phase change temperature is high and the water transmission rate is lower after aging, mainly because they can resist thermal invasion at higher temperatures.

[0053]

[0054]

[0055] Table 3

[0056] From the data in Table 3, it can be seen that the water permeability after aging can be reduced by combining high and low temperature inorganic phase change materials. The main reason is that inorganic phase change materials can mainly provide thermal protection for materials at different temperatures. The combination of organic phase change phenylacetic acid materials further reduces the water permeability after aging. However, naphthalene and benzylamine cannot complex with inorganic materials, and their adhesion is greatly reduced after volatilization. Although lauric acid can complex due to its low phase change temperature, it will also volatilize at high temperatures, so its adhesion is also low. When phenylacetic acid is added to 40%, it is difficult to completely bind phenylacetic acid due to the reduction of inorganic materials, so the adhesion and water permeability after aging decrease. Therefore, the amount of phenylacetic acid added should be between 10-30%.

[0057] It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary experimental examples, and that the present invention can be implemented in other specific forms without departing from the spirit and essential features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0058] In addition, it should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent claim scheme. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A water-blocking film, characterized in that: The water-blocking film comprises a base film layer, an oxide water-blocking layer and a polymer protective layer which are stacked in sequence. The polymer protective layer comprises a resin, a curing agent, a coupling aid, a heat dissipation material, a phase change material and an antioxidant. The mass ratio of the above substances is resin: curing agent: phase change material: heat dissipation material: coupling material: antioxidant = 100: (0.3-2.0): (0.3-3): (5-15): (0.3-5): (0.3-2.4).

2. A water-blocking film according to claim 1, characterized in that: The resin is acrylic resin or polyurethane resin, and the curing agent is isocyanate curing agent.

3. The water-blocking film according to claim 1, characterized in that: The base film layer is selected from one of PET, PI and PP, and the thickness of the base film layer is 1.5-500 μm.

4. The water-blocking film according to claim 1, characterized in that: The oxide water-blocking layer comprises a silicon dioxide coating layer and an aluminum oxide coating layer. The thickness of the oxide water-blocking layer is 10-100 nm, and the thickness of the polymer protective layer is 0.1-3 μm.

5. The water-blocking film according to claim 1, characterized in that: The antioxidant is selected from at least one of a phenol antioxidant 1010 and a phosphate antioxidant 245 , and the heat dissipation material is selected from one or both of graphite and boron nitride.

6. The water-blocking film according to claim 1, characterized in that: The phase change material is selected from one or more of magnesium sulfate heptahydrate, sodium sulfite pentahydrate, barium hydroxide octahydrate, and aluminum nitrate nonahydrate, or a combination of one or more of magnesium sulfate heptahydrate, sodium sulfite pentahydrate, barium hydroxide octahydrate, and aluminum nitrate nonahydrate and phenylacetic acid.

7. The water-blocking film according to claim 6, characterized in that: The phase change material is a combination of magnesium sulfate heptahydrate and barium hydroxide octahydrate or magnesium sulfate heptahydrate and aluminum nitrate nonahydrate, with a mass ratio of 1:1, or a combination of magnesium sulfate heptahydrate, barium hydroxide octahydrate and phenylacetic acid, wherein the addition amount of phenylacetic acid is 10-30%, and the mass ratio of magnesium sulfate heptahydrate to barium hydroxide octahydrate is 1:

1.

8. The water-blocking film according to claim 1, characterized in that: The coupling aid is selected from one or more of ethoxysilane oligomers, methoxysilane oligomers, and aluminum acetylacetonate.

9. A method for preparing a water-blocking film according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: S1 Preparation of polymer protective layer coating liquid: gradually add curing agent, coupling agent, heat dissipation material, phase change material and antioxidant to acrylic resin according to proportion, stir evenly and set aside; S2: The coating liquid prepared in step S1 is coated onto the substrate coated with the oxide water-blocking layer through a wire rod, and first cured and then aged to obtain the water-blocking film.

10. The method for preparing a water-blocking film according to claim 9, characterized in that: The curing temperature is 110-130° C., the curing time is 1-5 minutes, the curing temperature is 30-50° C., and the curing time is 72-96 hours.

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