Environment-friendly water-soluble pressure-sensitive adhesive and preparation process thereof

Abstract

The invention provides an environment-friendly water-soluble pressure-sensitive adhesive and a preparation process thereof, and belongs to the technical field of pressure-sensitive adhesives, the environment-friendly water-soluble pressure-sensitive adhesive comprises the following raw materials by weight: 60-90 parts of a modified acrylate polymer, 1-5 parts of an emulsifier, 0.1-1 part of a pH regulator, 0.05-0.1 part of a stabilizer, and 5-10 parts of ethylene glycol. According to the environment-friendly water-soluble pressure-sensitive adhesive and the preparation process thereof provided by the invention, the pressure-sensitive adhesive can be dissolved in water and is convenient to recycle and treat, and the aim of being more environment-friendly is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of pressure-sensitive adhesives, and in particular to an environmentally friendly water-soluble pressure-sensitive adhesive and a preparation process thereof. Background Art

[0002] The full name of pressure-sensitive adhesive is pressure-sensitive adhesive, also commonly known as self-adhesive, or simply pressure-sensitive adhesive. Pressure-sensitive adhesive products include three categories: pressure-sensitive adhesive tapes, pressure-sensitive adhesive label paper, and pressure-sensitive film. Pressure-sensitive adhesive is a viscoelastic body that has both the viscous properties of a liquid and the elastic properties of a solid; this viscoelastic body has the ability to withstand both the contact process and the destruction process of bonding.

[0003] Water-based pressure-sensitive adhesive is a common glue used to make tapes, labels, etc., with good initial adhesion, high peeling and other characteristics. Publication number CN111607340A, titled A water-based pressure-sensitive adhesive and its preparation method, discloses a water-based pressure-sensitive adhesive, the raw materials of which include 20-60 parts of butyl acrylate, 1-15 parts of acrylate compounds, 2-20 parts of isooctyl acrylate, 1-10 parts of emulsifier, 0.1-1 parts of oily initiator, 0.5-5 parts of thickener, 1-5 parts of buffer and 20-60 parts of water. By selecting an oily initiator, when the polymerization reaction occurs, the initiator can be initiated inside the emulsion microspheres, so that the polymerization reaction of the resin is more complete, the monomer residue is reduced, and the waste of raw materials is reduced. However, the above technical solutions and the water-based pressure-sensitive adhesives in the prior art still have the characteristic that the adhesive cannot be quickly dissolved in water after drying into a film. In the field of environmental recycling, the adhesive must be cleaned separately before substrates such as paper and film can be recycled. The processing process is not environmentally friendly and labor-intensive. Summary of the invention

[0004] In view of this, the present invention provides an environmentally friendly water-soluble pressure-sensitive adhesive and a preparation process thereof, so that the pressure-sensitive adhesive can be dissolved in water, which is convenient for recycling and treatment, thereby achieving a more environmentally friendly purpose.

[0005] To achieve the above object, the present invention provides an environmentally friendly water-soluble pressure-sensitive adhesive, comprising the following raw materials: modified acrylate polymer, emulsifier, pH regulator, stabilizer, and ethylene glycol.

[0006] Optionally, the following raw materials are included in parts by weight: 60-90 parts of modified acrylate polymer, 1-5 parts of emulsifier, 0.1-1 parts of pH adjuster, 0.05-0.1 parts of stabilizer, and 5-10 parts of ethylene glycol.

[0007] Optionally, the modified acrylic ester polymer includes the following raw materials: acrylic acid monomer, acrylic ester compound, initiator, chain transfer agent and water.

[0008] Optionally, the modified acrylic ester polymer comprises the following raw materials in parts by weight: 60-90 parts of acrylic monomer, 10-30 parts of acrylic ester compound, 0.1-1 part of initiator, 0.05-0.1 part of chain transfer agent, and 5-10 parts of water.

[0009] Optionally, the preparation of the modified acrylate polymer comprises the following steps: Step 1: Mix water, acrylic acid ester compound and chain transfer agent while maintaining heating and stirring; Step 2: After dissolving the initiator, the initiator solution is added dropwise to the reaction system; Step 3: Add acrylic acid monomer dropwise to the reaction system. After the addition is completed, keep the temperature for 0.5 to 1 hour, cool, wash and dry to obtain a modified acrylic ester polymer.

[0010] Optionally, the acrylic ester compound is one or a combination of two or more of methyl methacrylate, butyl acrylate and vinyl acetate.

[0011] Optionally, the heating temperature is 60~90°C.

[0012] Optionally, the dropwise addition in step 2 is performed using a separatory funnel or a constant flow pump.

[0013] To achieve the above object, the present invention also provides a preparation process of an environmentally friendly water-soluble pressure-sensitive adhesive, comprising the following steps: taking 5 to 10 parts of ethylene glycol and 1 to 5 parts of an emulsifier, maintaining heating and stirring; dripping 60 to 90 parts of a modified acrylate polymer in batches, and simultaneously dripping 0.1 to 1 part of a pH adjuster and 0.05 to 0.1 part of a stabilizer; after the dripping is completed, keeping warm for 0.5 to 1 hour.

[0014] The above technical solution of the present invention includes at least the following beneficial effects: The environmentally friendly water-soluble pressure-sensitive adhesive provided by the present invention has a simple process and is soluble in water through the combined action of the modified acrylate polymer provided by the present invention and other raw materials. After being applied to substrates such as paper and film, there is no need to clean the adhesive layer separately during recycling. After being dissolved in water, it is easy to handle and is environmentally friendly. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in combination with the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0016] The acrylic acid ester compound used in the embodiment of the present invention is one or a combination of two or more of methyl methacrylate, butyl acrylate and vinyl acetate, the initiator is ammonium persulfate, and the raw materials not specifically specified are the models commonly used in the industry and can achieve the corresponding effects.

[0017] Example 1 Maintaining heating and stirring at 60°C, 5 parts of water, 20 parts of methyl methacrylate and 0.05 parts of chain transfer agent were mixed in a reactor; 0.5 parts of ammonium persulfate were dissolved and the ammonium persulfate solution was slowly added dropwise to the reaction system through a separatory funnel; after the above initiator began to act, 80 parts of acrylic acid monomer were added dropwise to the reaction system to maintain a constant degree of polymerization. After the addition was completed, the mixture was kept warm for 0.5h, cooled to room temperature, washed and dried to obtain a modified acrylate polymer.

[0018] Heat to maintain 80°C and stir, add 10 parts of ethylene glycol and 1 part of emulsifier to the reactor, slowly drop 60 parts of modified acrylate polymer in three times to avoid aggregation leading to uneven emulsification, and drop 0.1 parts of pH adjuster and 0.1 parts of stabilizer respectively, maintain the pH value at 7-8, and form a stable emulsion. After the addition is completed, keep warm for 1 hour.

[0019] Example 2 Maintaining heating and stirring at 90°C, 10 parts of water, 20 parts of methyl methacrylate, 10 parts of butyl acrylate and 0.1 parts of chain transfer agent were mixed in a reaction kettle; 1 part of ammonium persulfate was dissolved and the ammonium persulfate solution was slowly dripped into the reaction system through a separatory funnel; after the above initiator began to act, 60 parts of acrylic acid monomer were dripped into the reaction system to maintain a constant degree of polymerization. After the dripping was completed, the mixture was kept warm for 1 hour, cooled to room temperature, washed and dried to obtain a modified acrylate polymer.

[0020] Heat to maintain 60°C and stir, add 5 parts of ethylene glycol and 5 parts of emulsifier to the reactor, slowly drop 90 parts of modified acrylate polymer in three times to avoid aggregation leading to uneven emulsification, and drop 1 part of pH regulator and 0.05 part of stabilizer respectively, maintain the pH value at 7-8, and form a stable emulsion. After the addition is completed, keep warm for 0.5h.

[0021] Example 3 Maintaining heating and stirring at 80°C, 8 parts of water, 10 parts of methyl methacrylate, 20 parts of vinyl acetate and 0.07 parts of chain transfer agent were mixed in a reactor; 0.5 parts of ammonium persulfate was dissolved and the ammonium persulfate solution was slowly added dropwise to the reaction system through a separatory funnel; after the above initiator began to act, 80 parts of acrylic acid monomer was added dropwise to the reaction system to maintain a constant degree of polymerization. After the addition was completed, the mixture was kept warm for 1 hour, cooled to room temperature, washed and dried to obtain a modified acrylate polymer.

[0022] Heat to maintain 70°C and stir, add 7 parts of ethylene glycol and 3 parts of emulsifier to the reactor, slowly drop 80 parts of modified acrylate polymer in three times to avoid aggregation leading to uneven emulsification, and drop 0.5 parts of pH regulator and 0.06 parts of stabilizer respectively, maintain the pH value at 7-8, and form a stable emulsion. After the addition is completed, keep warm for 0.5h.

[0023] The performance of the water-soluble pressure-sensitive adhesive prepared in Example 1 was tested, and the results are shown in Table 1.

[0024] Table 1 Performance test data of water-soluble pressure-sensitive adhesive

[0025] It can be seen from the analysis in combination with Table 1 that the water-soluble pressure-sensitive adhesive provided by the present invention meets the corresponding performance limit test requirements, and as the amount used increases, its annular initial adhesion, holding force and 180° peel strength performance are stronger. On the other hand, the water-soluble pressure-sensitive adhesive provided by the present invention is easy to recycle after application, and is an environmentally friendly adhesive.

[0026] In the present invention, unless otherwise clearly stipulated and limited, for example, it can be a fixed connection, a detachable connection, or an integrated one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, for ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0027] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An environmentally friendly water-soluble pressure-sensitive adhesive, characterized in that: The invention comprises the following raw materials: modified acrylic ester polymer, emulsifier, pH adjuster, stabilizer and ethylene glycol.

2. The environmentally friendly water-soluble pressure-sensitive adhesive according to claim 1, characterized in that: The invention comprises the following raw materials in parts by weight: 60-90 parts of modified acrylic ester polymer, 1-5 parts of emulsifier, 0.1-1 parts of pH regulator, 0.05-0.1 parts of stabilizer and 5-10 parts of ethylene glycol.

3. The environmentally friendly water-soluble pressure-sensitive adhesive according to claim 1, characterized in that: The modified acrylic ester polymer comprises the following raw materials: acrylic acid monomer, acrylic ester compound, initiator, chain transfer agent and water.

4. The environmentally friendly water-soluble pressure-sensitive adhesive according to claim 3, characterized in that: The modified acrylic ester polymer comprises the following raw materials in parts by weight: 60-90 parts of acrylic monomer, 10-30 parts of acrylic ester compound, 0.1-1 part of initiator, 0.05-0.1 part of chain transfer agent and 5-10 parts of water.

5. The environmentally friendly water-soluble pressure-sensitive adhesive according to claim 3, characterized in that: The preparation of the modified acrylate polymer comprises the following steps: Step 1: Mix water, acrylic acid ester compound and chain transfer agent while maintaining heating and stirring; Step 2: After dissolving the initiator, the initiator solution is added dropwise to the reaction system; Step 3: Add acrylic acid monomer dropwise to the reaction system. After the addition is completed, keep the temperature for 0.5 to 1 hour, cool, wash and dry to obtain a modified acrylic ester polymer.

6. The environmentally friendly water-soluble pressure-sensitive adhesive according to claim 5, characterized in that: The acrylic acid ester compound is one or a combination of two or more of methyl methacrylate, butyl acrylate and vinyl acetate.

7. The environmentally friendly water-soluble pressure-sensitive adhesive according to claim 5, characterized in that: The heating temperature is 60-90°C.

8. The environmentally friendly water-soluble pressure-sensitive adhesive according to claim 5, characterized in that: In the step 2, a separatory funnel or a constant flow pump is used for dropwise addition.

9. A process for preparing the environmentally friendly water-soluble pressure-sensitive adhesive according to any one of claims 1 to 8, characterized in that: The following steps are involved: Take 5-10 parts of ethylene glycol and 1-5 parts of emulsifier, keep heating and stirring; add 60-90 parts of modified acrylate polymer in batches, and at the same time, add 0.1-1 parts of pH adjuster and 0.05-0.1 parts of stabilizer respectively; After the addition is complete, keep warm for 0.5~1h.

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