Solvent type polyacrylate pressure-sensitive adhesive with high weather resistance, high stripping and persistent adhesion and polymerization method of solvent type polyacrylate pressure-sensitive adhesive

Abstract

The invention relates to the technical field of adhesive polymerization, in particular to a solvent type polyacrylate pressure-sensitive adhesive with high weather resistance and high stripping persistent adhesion and a polymerization method thereof, and the formula of the pressure-sensitive adhesive comprises an acrylate monomer, an organic solvent, a cross-linking agent and an initiator; the acrylate monomer comprises a hard monomer, a soft monomer and a functional monomer; in the acrylate monomers, a hard monomer accounts for 30-60% of the total amount of the formula; the soft monomer accounts for 40-70% of the total amount of the acrylate monomer; the functional monomer accounts for 3%-10% of the total amount of the acrylate monomer; the organic solvent and the initiator respectively account for 0.2%-0.5% of the total amount of the acrylate monomers; the cross-linking agent accounts for 0.2%-0.8% of the total amount of the acrylate monomers. The production cost of the glue is reduced, the production efficiency of the glue is improved, meanwhile, the glue is kept stable and transparent and colorless in appearance, stable viscosity, good leveling property and no impurities are kept for a long time in the using process of the glue, and the glue has better initial adhesion, stripping force and persistent adhesion. And the glue is more stable and easier to fit, is easy to replace and does not leave residual glue.

Description

Technical Field

[0001] The invention relates to the technical field of adhesive polymerization, in particular to a solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion and a polymerization method thereof. Background Art

[0002] Pressure-sensitive adhesives are classified into four categories according to their characteristics and usage: water-based emulsion pressure-sensitive adhesives, UV-curable pressure-sensitive adhesives, solvent-based pressure-sensitive adhesives, and hot-melt pressure-sensitive adhesives. Car covers are generally composed of substrates, adhesives, and coatings, and the production processes of different car covers are quite different. Most of the widely used solvent-based pressure-sensitive adhesives on the market are water-resistant, but the quality of adhesives made by different manufacturers is often uneven. For example, when the adhesive is polymerized, different production processes have different production efficiencies and different product qualities, and sometimes the product appearance is yellow and opaque; for example, during the coating process of the glue, the viscosity of the glue rises rapidly within a short period of time, or there are too many particles in the glue, causing the filter element to be blocked, etc.; during the final use of the car cover, the low peel strength causes the car cover to be poorly adhered during construction, and the high peel strength causes difficulty in peeling when replacing. What's more, it will damage the original paint of the car, the poor weather resistance of the glue leads to frequent product replacement, and the low degree of polymerization of the glue causes a large amount of residual glue when peeling, etc., while imported ones are often expensive and have high use costs.

[0003] Therefore, in order to correct the above defects, we propose a solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and adhesion retention and a polymerization method thereof. Summary of the invention

[0004] The technical problem solved by the present invention is to propose a solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion and a polymerization method thereof, and to select and use suitable acrylate monomers, appropriate solvents, and cross-linking agents through suitable proportions and efficient polymerization processes to achieve a polymer adhesive that is suitable for car cover films, stable, easy to use, highly weather-resistant, high peeling and high lasting adhesion, and has a lower cost.

[0005] To achieve the above object, the present invention provides the following technical solution: a solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion, the formula of which includes acrylate monomers, organic solvents, cross-linking agents, and initiators;

[0006] The acrylic ester monomers include hard monomers, soft monomers and functional monomers;

[0007] In the acrylic ester monomers, the hard monomers account for 30%-60% of the total amount of the formula; the soft monomers account for 40%-70% of the total amount of the acrylic ester monomers; and the functional monomers account for 3%-10% of the total amount of the acrylic ester monomers.

[0008] The organic solvent and the initiator each account for 0.2%-0.5% of the total amount of the acrylate monomer;

[0009] The crosslinking agent accounts for 0.2%-0.8% of the total amount of the acrylic ester monomers.

[0010] Furthermore, the hard monomer is one or more of methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, methyl acrylate, vinyl acetate, and isobornyl acrylate.

[0011] The soft monomer is one or more of ethyl acrylate, n-butyl acrylate, and isooctyl acrylate.

[0012] The functional monomer is one or more of acrylic acid, methacrylic acid, hydroxypropyl acrylate, and glycidyl methacrylate.

[0013] The organic solvent is used for the coordination reaction, and is one or more of ethyl acetate, butyl acetate, acetone, butanone, methylcyclohexanone, toluene, n-hexane, n-heptane, cyclohexane A, toluene, ethanol, n-propanol, and isopropanol. According to the boiling point of the organic solvent, three of them are selected for polymerization and viscosity adjustment according to a certain temperature gradient.

[0014] The initiator is one of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide and dodecanoyl peroxide.

[0015] The coupling agent is one or more of aluminum acetylacetonate, chromium acetylacetonate, and isocyanate.

[0016] Another object of the present invention is to provide a polymerization method for a solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and tack retention, comprising the following steps:

[0017] S1, adding an organic solvent to the acrylic ester monomer, and then entering the pre-emulsification kettle for stirring;

[0018] S2, adding an organic solvent to the initiator, and then entering the initiator kettle for stirring;

[0019] S3, heating the polymerization kettle, then dropping the mixture in step S1 and step S2 into the polymerization kettle, carrying out polymerization reaction in the polymerization kettle for 2 hours, and then keeping the temperature for 3 hours;

[0020] S4, cooling the polymer after being kept in the polymerization kettle for 3 hours, and adding a cross-linking agent during the cooling process;

[0021] S5. Add organic solvent to adjust viscosity according to usage, then cool down, discharge, filter and test.

[0022] Furthermore, in step S3, before the mixture in step S1 and step S2 is added dropwise into the polymerization kettle, the polymerization kettle is heated to 80°C, and the temperature of the polymerization kettle during the polymerization reaction for 2 hours is 80-85°C.

[0023] Compared with the prior art, the invention has the following beneficial effects: reducing the production cost of glue, improving the production efficiency of glue, and keeping the glue stable, transparent and colorless in appearance, and keeping the viscosity stable for a long time during its use, with good leveling and no impurities, and having better initial adhesion, peeling force and lasting adhesion. The glue is more stable and easier to fit, easy to replace and does not leave any residual glue. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the polymer polymerization process in the present invention;

[0025] Figure 2 It is a schematic diagram of the polymerization reaction principle in the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The present invention provides a technical solution:

[0028] See also Figure 1-2 , a solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and adhesion, the formula of which includes acrylate monomers, organic solvents, cross-linking agents, and initiators;

[0029] The acrylic ester monomers include hard monomers, soft monomers and functional monomers;

[0030] In the acrylic ester monomers, the hard monomers account for 30%-60% of the total amount of the formula; the soft monomers account for 40%-70% of the total amount of the acrylic ester monomers; and the functional monomers account for 3%-10% of the total amount of the acrylic ester monomers.

[0031] The organic solvent and the initiator each account for 0.2%-0.5% of the total amount of the acrylate monomer;

[0032] The crosslinking agent accounts for 0.2%-0.8% of the total amount of the acrylic ester monomers.

[0033] Furthermore, the hard monomer is one or more of methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, methyl acrylate, vinyl acetate, and isobornyl acrylate.

[0034] The soft monomer is one or more of ethyl acrylate, n-butyl acrylate, and isooctyl acrylate.

[0035] The functional monomer is one or more of acrylic acid, methacrylic acid, hydroxypropyl acrylate, and glycidyl methacrylate.

[0036] The organic solvent is used for the coordination reaction, and is one or more of ethyl acetate, butyl acetate, acetone, butanone, methylcyclohexanone, toluene, n-hexane, n-heptane, cyclohexane A, toluene, ethanol, n-propanol, and isopropanol. According to the boiling point of the organic solvent, three of them are selected for polymerization and viscosity adjustment according to a certain temperature gradient.

[0037] The initiator is one of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide and dodecanoyl peroxide.

[0038] The coupling agent is one or more of aluminum acetylacetonate, chromium acetylacetonate, and isocyanate.

[0039] The process of the polymerization method of the solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and adhesion is as follows Figure 1 The polymerization reaction principle is as shown in Figure 2 As shown, some R1 and R2 in Formula 1 can be -COOC9H 17、 -COOC4H9, -COOCH3, -C6H5, -COOC2H, etc. This is an addition polymerization reaction. R3COOH, R4COOH, and R5COOH in formula 2 are polymers containing terminal carboxyl groups.

[0040] Example

[0041] Isooctyl acrylate and butyl acrylate are used as the soft monomers of this formula, and the amount of the two is 40%-70% of the total monomers. Methyl acrylate is used as the hard monomer of this formula, and the amount is 30%-60% of the formula. Acrylic acid is used as the functional monomer of this formula, and the amount is 3%-10% of the total monomers. Ethyl acetate, toluene, and methylcyclohexane are selected as the organic solvents used, and dodecyl peroxide is used as the initiator. The amount used is 0.2%-0.5% of the total monomers. Aluminum acetylacetonate is used as a post-crosslinking agent, and the amount used is about 0.2%-0.8% of the total monomers.

[0042] Toluene and methylcyclohexane are used as the reaction solvents of this formula. The selected monomers are mixed evenly with the organic solvent for reaction at a solid content of 60% in the pre-reactor, and the initiator is fully dissolved in the initiator kettle with toluene. The reactor is fully purged with nitrogen before the monomer reaction, and the condenser is passed through circulating water. Before heating, 20% of the reaction mixture is subjected to a base reaction, and then 20% of the prepared initiator liquid is added for full stirring, and the temperature is raised to 80-85°C and kept warm until obvious reaction phenomenon appears on the liquid surface and the viscosity of the solution increases significantly. The remaining reaction liquid can be added dropwise until there is no obvious reflux in the condenser, and 20% of the initiator liquid is added dropwise at the same time to maintain the continuity of the entire reaction, and the dropping process lasts at least 2h. After the dropwise addition is completed, keep warm for 1h, and then add the remaining initiator liquid dropwise at a uniform speed to react the residual monomers in the system thoroughly. Then continue to keep warm, and the entire insulation time lasts at least 2h until the previous follow-up reaction is completed.

[0043] After the pre-reaction is completed, cool down to 70℃ and keep warm. At the same time, add an appropriate amount of ethyl acetate to adjust the viscosity. At the same time, use ethyl acetate to fully dissolve the post-crosslinking agent in the pre-reaction kettle. After fully dissolved, add it dropwise to the glue solution after the pre-reaction is completed. At the same time, increase the stirring speed and stir it evenly until the cross-linking reaction is completed, which takes no less than 30 minutes. After the reaction is completed, add the remaining ethyl acetate to adjust to a suitable viscosity for subsequent use. At this time, the polymer glue reaction is complete.

[0044] Reduce the production cost of glue, improve the production efficiency of glue, keep the appearance of glue stable, transparent and colorless, keep the viscosity stable for a long time during its use, have good leveling and no impurities, have better initial adhesion, peeling force and lasting adhesion. The glue is more stable and easier to fit, easy to replace and no residual glue is left.

[0045] The data is shown in the following table for reference:

[0046]

[0047] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion, characterized in that: Its formula includes acrylate monomer, organic solvent, cross-linking agent and initiator; The acrylic ester monomers include hard monomers, soft monomers and functional monomers; In the acrylic ester monomers: hard monomers account for 30%-60% of the total formula; soft monomers account for 40%-70% of the total acrylic ester monomers; functional monomers account for 3%-10% of the total acrylic ester monomers; The organic solvent and the initiator account for 0.2%-0.5% of the total amount of the acrylate monomers respectively; The crosslinking agent accounts for 0.2%-0.8% of the total amount of the acrylate monomers.

2. The solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion according to claim 1, characterized in that: The hard monomer is one or more of methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, methyl acrylate, vinyl acetate, and isobornyl acrylate.

3. The solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion according to claim 1, characterized in that: The soft monomer is one or more of ethyl acrylate, n-butyl acrylate, and isooctyl acrylate.

4. The solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion according to claim 1, characterized in that: The functional monomer is one or more of acrylic acid, methacrylic acid, hydroxypropyl acrylate, and glycidyl methacrylate.

5. The solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion according to claim 1, characterized in that: The organic solvent is used for the coordination reaction, and is one or more of ethyl acetate, butyl acetate, acetone, butanone, methylcyclohexanone, toluene, n-hexane, n-heptane, cyclohexane A, toluene, ethanol, n-propanol, and isopropanol. According to the boiling point of the organic solvent, three of them are selected for polymerization and viscosity adjustment according to a certain temperature gradient.

6. The solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion according to claim 1, characterized in that: The initiator is one of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide and dodecanoyl peroxide.

7. The solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion according to claim 1, characterized in that: The coupling agent is one or more of aluminum acetylacetonate, chromium acetylacetonate, and isocyanate.

8. A method for polymerizing a solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion as claimed in any one of claims 1 to 7, characterized in that: The steps include: S1, adding an organic solvent to the acrylic ester monomer, and then entering the pre-emulsification kettle for stirring; S2, adding an organic solvent to the initiator, and then entering the initiator kettle for stirring; S3, heating the polymerization kettle, then dropping the mixture in step S1 and step S2 into the polymerization kettle, carrying out polymerization reaction in the polymerization kettle for 2 hours, and then keeping the temperature for 3 hours; S4, cooling the polymer after being kept in the polymerization kettle for 3 hours, and adding a cross-linking agent during the cooling process; S5. Add organic solvent to adjust viscosity according to usage, then cool down, discharge, filter and test.

9. The polymerization method of the solvent-based polyacrylate pressure-sensitive adhesive with high weather resistance and high peeling and lasting adhesion according to claim 8, characterized in that: In the step S3, before the mixture in the step S1 and the step S2 is added dropwise into the polymerization kettle, the polymerization kettle is heated to 80°C, and the temperature of the polymerization kettle during the polymerization reaction for 2 hours is 80-85°C.

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