Preparation method of water vapor barrier resin prepolymer and water vapor barrier coating

Abstract

The invention discloses a water vapor barrier coating, which is composed of the following components by mass: 8-12 parts of organosilicon acrylic resin; 10-16 parts of a water vapor barrier resin prepolymer; 0.5 to 4 parts of a coupling agent; 0.5-2 parts of a dispersant; the organic silicon acrylic resin is selected from poly (triethoxysilyl) propyl methacrylate and poly (trimethylsilyl) methyl methacrylate, the coupling agent is a silane coupling agent, the dispersing agent is polyether modified polydimethylsiloxane, and the solvent is a mixed solvent of butyl acetate, isopropanol and methyl isobutyl ketone in a volume ratio of 3: 1: 2. In addition, the invention also discloses a preparation method of the water vapor barrier resin prepolymer. The water vapor barrier coating can be used for a water vapor barrier functional coating of a film, and plays an important role in the fields of photovoltaic cells, OLED packaging and the like.

Description

Technical Field

[0001] The invention relates to a water vapor barrier coating and a method for preparing a water vapor barrier resin prepolymer as a main functional component thereof. Background Art

[0002] Water vapor has a penetrating and corrosive effect on materials such as films, wood, and metals, often causing the performance of various materials to deteriorate, making it difficult for them to play their due role. With the advancement of science and technology, the widespread application of outdoor instruments and equipment, precision instruments, and high-end products, as well as people's increasing requirements for product effectiveness and durability, have become the focus of attention. As a result, the functional requirements for water vapor barriers have become increasingly higher.

[0003] Water vapor barrier coatings can provide a simple treatment method. By applying a layer of coating on the surface of the material, the water vapor barrier function can be achieved, and it has attracted widespread attention.

[0004] Chinese patent CN107903803A discloses a high vapor barrier polyurethane coating for cold storage. By selecting component A containing isocyanate and polyether polyol, and component B containing fluorine-containing acrylic resin, polyether polyol and other additives, a two-component coating is formed, which can be used for the vapor barrier function of the polyurethane external insulation system.

[0005] Chinese patent CN115233493A discloses a water vapor barrier coating, which is prepared by compounding nano metal sheets, adhesives, nano cellulose and other additives, and can be used for the water vapor barrier function of paper-based materials. The composition of these coatings is relatively complex and the application field is relatively single.

[0006] Improving the universality of coatings, reducing application costs, and improving water vapor barrier properties are currently a major urgent need in this field. Summary of the invention

[0007] In view of the above-mentioned deficiencies of the existing methods and technologies, according to an embodiment of the present invention, it is hoped to provide a water vapor barrier coating that can achieve outstanding water vapor barrier performance through simple and effective preparation; in addition, the present invention also aims to propose a method for preparing a water vapor barrier resin prepolymer, which is the main functional component of the water vapor barrier coating.

[0008] According to an embodiment, the present invention provides a method for preparing a water vapor barrier resin prepolymer, comprising the following steps:

[0009] (1) According to the mass ratio, 10 parts of ethylene-vinyl alcohol copolymer were dissolved in 200 parts of dimethyl sulfoxide, which was recorded as solution A; 5 parts of hydroxylated flaky nanosilica and 0.3 parts of polyvinyl pyrrolidone were dissolved and dispersed uniformly in another 100 parts of dimethyl sulfoxide, which was recorded as solution B;

[0010] (2) Solution B is dripped into Solution A at a rate of (5-10) ml / min, ultrasonically stirred for 0.5-1.5 h, 0.5-1 part of coupling agent is added, heated to 80-100°C, and stirred for 1-3 h;

[0011] (3) returning to room temperature, washing by centrifugal separation, and vacuum drying at 40° C. for 36-48 hours to obtain a water vapor barrier resin prepolymer.

[0012] According to one embodiment, in step (1) of the method for preparing the water vapor barrier resin prepolymer of the present invention, the molar content of ethylene in the ethylene-vinyl alcohol copolymer is preferably 30-40%; the particle size of the hydroxylated flaky nano-silica is preferably 0.5-2 μm, and the thickness is preferably 30-50 nm.

[0013] According to one embodiment, in step (2) of the method for preparing the water vapor barrier resin prepolymer of the present invention, the coupling agent is vinyl triethoxysilane and tetramethyl divinyl disilazane, and the mass ratio is preferably 1:(0.3-0.5).

[0014] According to an embodiment, the present invention provides a water vapor barrier coating, the composition and mass parts of which are:

[0015] 8-12 parts of silicone acrylic resin;

[0016] 10-16 parts of water vapor barrier resin prepolymer;

[0017] Coupling agent 0.5-4 parts;

[0018] Dispersant 0.5-2 parts;

[0019] 60-80 parts of solvent, wherein:

[0020] The silicone acrylic resin is preferably selected from polytriethoxysilylpropyl methacrylate and polytrimethylsilylmethyl methacrylate, the coupling agent is preferably a silane coupling agent, the dispersant is preferably polyether-modified polydimethylsiloxane, and the solvent is preferably a mixed solvent of butyl acetate, isopropanol and methyl isobutyl ketone in a volume ratio of 3:1:2.

[0021] The preparation method of the water vapor barrier coating of the present invention is not special, and the components are mixed and stirred evenly.

[0022] Compared with the prior art, the water vapor barrier coating provided by the present invention uses a water vapor barrier resin prepolymer as the main functional component and can be applied to water vapor barrier coatings of plastic films, plates and other products. The following examples and test examples will prove that compared with the prior art, the preparation method of the water vapor barrier coating is simple and has the outstanding characteristics of simple construction and high performance. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with specific embodiments. These embodiments should be understood to be only used to illustrate the present invention and not to limit the scope of protection of the present invention. After reading the content of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent changes and modifications also fall within the scope defined by the claims of the present invention.

[0024] In the following examples of the present invention, hydroxylated flaky nano-silica is prepared by the following method:

[0025] (1) 100 g of silica nanosheets were dispersed in 1 L of water and ultrasonically stirred for 3 h;

[0026] (2) Add 500 ml of 5 mol / L sodium hydroxide solution, heat to 80°C, and stir for 3 h;

[0027] (3) After natural cooling, the mixture was filtered and separated, and dried in a vacuum oven at 40° C. for 36 hours to obtain hydroxylated flaky nano-silica with a particle size of 0.5-2 μm and a thickness of 30-50 nm.

[0028] In the following examples of the present invention, the raw materials used are all commercially available products unless otherwise specified.

[0029] Example 1

[0030] The water vapor barrier resin prepolymer is prepared by the following method:

[0031] (1) 10 g of ethylene-vinyl alcohol copolymer (the molar content of ethylene is 30%) is dissolved in 200 g of dimethyl sulfoxide, which is referred to as solution A; 5 g of hydroxylated flaky nano-silica and 0.3 g of polyvinyl pyrrolidone are dissolved and dispersed uniformly in 100 g of dimethyl sulfoxide, which is referred to as solution B;

[0032] (2) Solution B was dripped into Solution A at a constant rate of 5 ml / min, ultrasonically stirred for 0.5 h, 0.5 g of vinyltriethoxysilane and 0.2 g of tetramethyldivinyldisilazane were added, the solution was heated to 85 °C, and stirred for 2 h;

[0033] (3) returning to room temperature, washing by centrifugation, and vacuum drying at 40° C. for 48 h to obtain a water vapor barrier resin prepolymer.

[0034] Weigh 10g of polytriethoxysilylpropyl methacrylate, 12g of water vapor barrier resin prepolymer, 0.5g of coupling agent KH550, 0.8g of polyether modified polydimethylsiloxane, and 65g of a mixed solvent of butyl acetate, isopropanol, and methyl isobutyl ketone (volume ratio of 3:1:2). Stir the mixture for 5h to obtain a water vapor barrier coating.

[0035] Example 2

[0036] The water vapor barrier resin prepolymer is prepared by the following method:

[0037] (1) 10 g of ethylene-vinyl alcohol copolymer (the molar content of ethylene is 40%) is dissolved in 200 g of dimethyl sulfoxide, which is referred to as solution A; 5 g of hydroxylated flaky nano-silica and 0.3 g of polyvinyl pyrrolidone are dissolved and dispersed uniformly in 100 g of dimethyl sulfoxide, which is referred to as solution B;

[0038] (2) Solution B was dripped into Solution A at a constant rate of 6 ml / min, ultrasonically stirred for 1 h, 0.6 g of vinyltriethoxysilane and 0.3 g of tetramethyldivinyldisilazane were added, the solution was heated to 90°C, and stirred for 3 h;

[0039] (3) returning to room temperature, washing by centrifugation, and vacuum drying at 40° C. for 48 h to obtain a water vapor barrier resin prepolymer.

[0040] Weigh 12g of polytriethoxysilylpropyl methacrylate, 16g of water vapor barrier resin prepolymer, 1.5g of coupling agent KH550, 1.2g of polyether modified polydimethylsiloxane, and 75g of a mixed solvent of butyl acetate, isopropanol, and methyl isobutyl ketone (volume ratio of 3:1:2). Stir the mixture for 5h to obtain a water vapor barrier coating.

[0041] Example 3

[0042] The water vapor barrier resin prepolymer is prepared by the following method:

[0043] (1) 10 g of ethylene-vinyl alcohol copolymer (the molar content of ethylene is 30%) is dissolved in 200 g of dimethyl sulfoxide, which is referred to as solution A; 5 g of hydroxylated flaky nano-silica and 0.3 g of polyvinyl pyrrolidone are dissolved and dispersed uniformly in 100 g of dimethyl sulfoxide, which is referred to as solution B;

[0044] (2) Solution B was dripped into Solution A at a constant rate of 8 ml / min, ultrasonically stirred for 1 h, 0.6 g of vinyltriethoxysilane and 0.2 g of tetramethyldivinyldisilazane were added, the solution was heated to 90°C, and stirred for 3 h;

[0045] (3) returning to room temperature, washing by centrifugation, and vacuum drying at 40° C. for 48 h to obtain a water vapor barrier resin prepolymer.

[0046] Weigh 12g of polytriethoxysilylpropyl methacrylate, 15g of water vapor barrier resin prepolymer, 0.8g of coupling agent KH560, 1g of polyether modified polydimethylsiloxane, and 70g of a mixed solvent of butyl acetate, isopropanol, and methyl isobutyl ketone (volume ratio of 3:1:2). Stir the mixture for 5h to obtain a water vapor barrier coating.

[0047] Test example

[0048] The water vapor barrier coating prepared in the above embodiments was coated on the surface of a PET film with a thickness of 65 μm, and baked at 80°C for 30 minutes to obtain a coating sample. The water vapor permeability performance of each sample was tested. The test results are shown in Table 1. The samples prepared in each embodiment have good water vapor barrier properties. The coating of Example 2 has relatively good water vapor barrier properties, mainly because its water vapor barrier prepolymer is more invested and is more closely combined with the overall resin system, thereby improving its barrier performance.

[0049] Table 1. Water vapor barrier performance test of each embodiment

[0050]

[0051] The water vapor barrier coating prepared by the present invention can be used for water vapor barrier functional coating of thin films, has good universality, and has good application prospects in the field of packaging and encapsulation materials.

Claims

1. A method for preparing a water vapor barrier resin prepolymer, characterized in that: The steps include: (1) According to the mass ratio, 10 parts of ethylene-vinyl alcohol copolymer were dissolved in 200 parts of dimethyl sulfoxide, which was recorded as solution A; 5 parts of hydroxylated flaky nanosilica and 0.3 parts of polyvinyl pyrrolidone were dissolved and dispersed uniformly in another 100 parts of dimethyl sulfoxide, which was recorded as solution B; (2) Solution B is dripped into Solution A at a rate of (5-10) ml / min, ultrasonically stirred for 0.5-1.5 h, 0.5-1 part of coupling agent is added, heated to 80-100°C, and stirred for 1-3 h; (3) returning to room temperature, washing by centrifugal separation, and vacuum drying at 40° C. for 36-48 hours to obtain a water vapor barrier resin prepolymer.

2. The method for preparing a water vapor barrier resin prepolymer according to claim 1, characterized in that: In step (1), the molar content of ethylene in the ethylene-vinyl alcohol copolymer is 30-40%.

3. The method for preparing a water vapor barrier resin prepolymer according to claim 1, characterized in that: In step (1), the particle size of the hydroxylated flaky nano-silicon dioxide is 0.5-2 μm and the thickness is 30-50 nm.

4. The method for preparing a water vapor barrier resin prepolymer according to claim 1, characterized in that: In step (2), the coupling agent is vinyltriethoxysilane and tetramethyldivinyldisilazane, and the mass ratio is 1:(0.3-0.5).

5. A water vapor barrier coating, characterized in that: It consists of the following components and mass parts: 8-12 parts of silicone acrylic resin; 10-16 parts of a water vapor barrier resin prepolymer prepared by the preparation method according to any one of claims 1 to 4; Coupling agent 0.5-4 parts; Dispersant 0.5-2 parts; 60-80 parts of solvent, wherein: The silicone acrylic resin is selected from polytriethoxysilylpropyl methacrylate and polytrimethylsilylmethyl methacrylate, the coupling agent is a silane coupling agent, the dispersant is polyether modified polydimethylsiloxane, and the solvent is a mixed solvent of butyl acetate, isopropyl alcohol and methyl isobutyl ketone in a volume ratio of 3:1:2.

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