High-cohesion low-displacement polyacrylate adhesive, polyacrylate pressure-sensitive adhesive tape and preparation method of polyacrylate adhesive and polyacrylate pressure-sensitive adhesive tape

Abstract

The invention discloses a polyacrylate adhesive with high cohesion and low displacement. The polyacrylate adhesive comprises the following raw materials in percentage by weight: 20-30% of an acrylate hard monomer, 10-15% of an acrylate soft monomer, 1-5% of a modified monomer, 0.1-0.5% of an initiator and 50-65% of an organic solvent, the preparation method of the adhesive comprises the following steps: (1) weighing 2 / 3 of an acrylate soft monomer, 2 / 3 of an acrylate hard monomer, 1 / 2 of a modified monomer and a solvent to obtain a mixed monomer A; uniformly mixing the rest 1 / 3 of the acrylate soft monomer, 1 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and an initiator to obtain a mixed monomer B; (2) adding the mixed monomer A into a reaction kettle at one time, heating to 60-80 DEG C in a water bath, and introducing nitrogen to exhaust air; adding the mixed monomer B into a funnel, dropwise adding the mixed monomer B into the mixed monomer A at a constant speed, and stirring at a constant speed of 200r / min; and (3) after dropwise adding the mixed monomer, keeping the temperature of the reaction kettle at 60-80 DEG C, continuously reacting for 4-6 hours, and cooling the polymer to room temperature to obtain the polyacrylate adhesive.

Description

Technical Field

[0001] The present invention relates to the technical field of adhesives, in particular to a polyacrylate adhesive with high cohesion and low displacement, a polyacrylate pressure-sensitive tape and a preparation method thereof. Background Art

[0002] As a crucial component of photovoltaic modules, frame tape provides sealing and insulation, preventing moisture from seeping through the module frame. This can affect the adhesion between the module backsheet, EVA, and glass, ultimately leading to delamination and other issues during actual use, significantly reducing module lifespan. Therefore, testing the performance of frame tape is crucial and directly impacts module performance.

[0003] The existing border tape has the following shortcomings: 1. The overall structure has a certain thickness and adhesive properties, showing excellent resistance to peeling and warping in narrow edge bonding. However, due to the thick adhesive layer of the frame tape, if the acrylic glue has poor internal cohesion and excessive fluidity, the performance will be unstable. During die-cutting, the adhesive layer may overflow and powder will fall off, affecting the appearance and cleanliness of the product and reducing production efficiency. 2. At room temperature, some frame tapes offer excellent adhesion. However, due to the lack of cohesion in the acrylic adhesive layer, the adhesive performance is unstable. This can lead to a decrease in the adhesiveness of the tape during transportation (which may be in extreme environments such as high temperature, high humidity, or low temperature), resulting in displacement, delamination between the adhesive layer and the adhered object, wrinkling or warping of the tape, and even peeling. 3. Some tapes used for large-screen narrow-frame displays have relatively simple material choices. Although they have good bonding properties, they are unable to simultaneously meet multiple requirements such as sealing, shock absorption, and thermal conductivity.

[0004] Therefore, how to provide a polyacrylate adhesive that has high cohesion, stable bonding performance, and can simultaneously meet multiple requirements such as sealing, shock absorption, and thermal conductivity has become a problem to be solved by those skilled in the art. Summary of the Invention

[0005] In order to overcome the deficiencies of the prior art, the object of the present invention is to provide a polyacrylate adhesive with high cohesion and low displacement, a polyacrylate pressure-sensitive tape and a preparation method thereof.

[0006] The purpose of the present invention is achieved by adopting the following technical solutions: According to an embodiment of the present disclosure, a polyacrylate adhesive with high cohesion and low displacement is provided, characterized in that it comprises the following raw materials in weight percentage: 20%-30% acrylate hard monomer, 10%-15% acrylate soft monomer, 1%-5% modified monomer, 0.1%-0.5% initiator, and 50%-65% organic solvent; The preparation method of the high cohesion and low displacement polyacrylate adhesive comprises the following steps: (1) Weigh 2 / 3 of the acrylate soft monomer, 2 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and a solvent to obtain a mixed monomer A; and uniformly mix the remaining 1 / 3 of the acrylate soft monomer, 1 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and an initiator to obtain a mixed monomer B; (2) Add the mixed monomer A into the reactor at one time, heat it in a water bath to 60-80°C, and introduce nitrogen to expel the air; add the mixed monomer B into the funnel and drop it into the mixed monomer A at a uniform speed, while stirring it at a speed of 200 r / min with a polytetrafluoroethylene stirring paddle to allow it to react fully, and control the dropwise addition time of the mixed monomer B to be 2-3 hours; (3) After the addition of the mixed monomers is completed, the temperature of the reactor is maintained at 60-80°C and the reaction is continued for 4-6 hours. The polymer is then cooled to room temperature to obtain a polyacrylate adhesive.

[0007] As a preferred solution, the modified monomer includes one or a combination of a monomer containing a carboxyl functional group and a monomer containing an amide group.

[0008] As a preferred solution, the carboxyl functional group-containing monomer includes one or more of methacrylic acid and acrylic acid.

[0009] As a preferred solution, the amide group-containing monomer includes ammonium acrylate.

[0010] The present invention also provides a polyacrylate pressure-sensitive adhesive tape, the raw materials for preparing which include the polyacrylate adhesive with high cohesion and low displacement of the above technical solution; The preparation method of the polyacrylate pressure-sensitive adhesive tape comprises the following steps: A. preparing the polyacrylate adhesive as described above, mixing the polypropylene carboxylate adhesive with a curing agent, a catalyst, a tackifying resin and a solvent and stirring uniformly to obtain a mixed adhesive; B. coating the mixed adhesive prepared in step A on the corona surface of the PET film to form a pressure-sensitive adhesive layer; C. Pull the PET film coated with the pressure-sensitive adhesive layer at a speed of 5 mm / s. After pulling, bake it at 110°C for 3-5 minutes; D. Laminating a layer of silicone oil release film on the baked pressure-sensitive adhesive layer, and then curing in a 50°C oven for 2 days. After curing, a polyacrylate pressure-sensitive adhesive tape is obtained.

[0011] The present invention also provides a polyacrylate pressure-sensitive adhesive tape, which is prepared by the preparation method of the polyacrylate pressure-sensitive adhesive tape of the above technical solution. The polyacrylate pressure-sensitive adhesive tape includes, from top to bottom, a silicone oil release layer, a polyacrylate pressure-sensitive adhesive layer and a PET substrate layer.

[0012] In summary, compared with the prior art, the present invention has the following beneficial effects: 1. Initiators introduce free radicals into the reaction environment and introduce functional groups into the polymer main chain to form graft copolymers, thereby obtaining polyacrylate adhesives with high cohesive force; 2. The polyacrylate adhesive and pressure-sensitive tape produced have the following properties: good peel strength, strong adhesion, no floating or debonding after hot and cold cycles, good adhesion and no displacement; 3. Through the monomer containing carboxyl functional group, the carboxyl group reacts with the cross-linking agent to form a network cross-linking structure and enhance the cohesion; 4. Through monomers containing amide groups, the amide groups can enhance the intermolecular forces by forming hydrogen bonds. At the same time, the amide groups can form a three-dimensional network structure by cross-linking reactions with other functional groups, such as carboxyl groups and hydroxyl groups, thereby significantly enhancing the cohesive force. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the structure of the polyacrylate pressure-sensitive adhesive tape of the present invention. DETAILED DESCRIPTION

[0014] The present invention provides a polyacrylate adhesive with high cohesion and low displacement, comprising the following raw materials in weight percentage: 20%-30% of acrylate hard monomer, 10%-15% of acrylate soft monomer, 1%-5% of modified monomer, 0.1%-0.5% of initiator, and 50%-65% of organic solvent; The preparation method of the high cohesion and low displacement polyacrylate adhesive comprises the following steps: (1) Weigh 2 / 3 of the acrylate soft monomer, 2 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and a solvent to obtain a mixed monomer A; and uniformly mix the remaining 1 / 3 of the acrylate soft monomer, 1 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and an initiator to obtain a mixed monomer B; (2) Add the mixed monomer A into the reactor at one time, heat it in a water bath to 60-80°C, and introduce nitrogen to expel the air; add the mixed monomer B into the funnel and drop it into the mixed monomer A at a uniform speed, while stirring it at a speed of 200 r / min with a polytetrafluoroethylene stirring paddle to allow it to react fully, and control the dropwise addition time of the mixed monomer B to be 2-3 hours; (3) After the addition of the mixed monomers is completed, the temperature of the reactor is maintained at 60-80°C and the reaction is continued for 4-6 hours. The polymer is then cooled to room temperature to obtain a polyacrylate adhesive.

[0015] In this way, by first blending the raw materials to obtain mixed monomer A and mixed monomer B, the molecular weight and molecular weight distribution of the polymer can be better controlled, the molecular weight of the polymer can be increased, and thus the cohesion and mechanical properties of the polyacrylate adhesive can be improved; first adding the mixed monomer A to the reactor and then adding the mixed monomer B dropwise into the reactor can effectively regulate the rate of the polymerization reaction and avoid heat accumulation and side reactions caused by too rapid a reaction.

[0016] Specifically, the modified monomer includes one or a combination of a monomer containing a carboxyl functional group and a monomer containing an amide group.

[0017] Specifically, the carboxyl functional group-containing monomer includes one or more of methacrylic acid and acrylic acid.

[0018] In this way, the monomer containing a carboxyl functional group (such as methacrylic acid CH2=C(CH3)-COOH and acrylic acid CH2=CH-COOH) reacts with the crosslinking agent through the carboxyl group in the polymerization reaction of the present application to form a network crosslinked structure, thereby enhancing the cohesion.

[0019] Specifically, the amide group-containing monomer includes ammonium acrylate.

[0020] Thus, in the polymerization reaction of the amide-containing monomer (such as acrylamide) of the present application, the amide group can form hydrogen bonds in the reaction to enhance the intermolecular force; in addition, acrylamide can also form a three-dimensional network structure by cross-linking reaction with other functional groups (such as carboxyl, hydroxyl, etc.), thereby significantly enhancing the cohesive force.

[0021] The present invention also provides a polyacrylate pressure-sensitive adhesive tape, the raw materials for preparing the tape include the polyacrylate adhesive with high cohesion and low displacement described in the above technical solution; The preparation method of the polyacrylate pressure-sensitive adhesive tape comprises the following steps: A. preparing the above-mentioned polyacrylate adhesive, mixing the polypropylene carboxylate adhesive with a curing agent, a catalyst, a tackifying resin and a solvent and stirring them uniformly to obtain a mixed adhesive; B. coating the mixed adhesive prepared in step A on the corona surface of the PET film to form a pressure-sensitive adhesive layer; C. Pull the PET film coated with the pressure-sensitive adhesive layer at a speed of 5 mm / s. After pulling, bake it at 110°C for 3-5 minutes; D. Laminating a layer of silicone oil release film on the baked pressure-sensitive adhesive layer, and then curing in a 50°C oven for 2 days. After curing, a polyacrylate pressure-sensitive adhesive tape is obtained.

[0022] Specifically, isocyanate is preferably used as the curing agent.

[0023] In this way, carboxyl groups are introduced into the polyacrylate adhesive, and the carboxyl groups can subsequently react with the curing agent (isocyanate) to form a three-dimensional network structure in the adhesive. This structure has good stability and can strengthen the cohesion of the adhesive itself.

[0024] The present invention also provides a polyacrylate pressure-sensitive adhesive tape, which is prepared by the above-mentioned polyacrylate pressure-sensitive adhesive tape preparation method, such as Figure 1 As shown, the polyacrylate pressure-sensitive adhesive tape comprises a silicone oil release layer 1, a polyacrylate pressure-sensitive adhesive layer 2 and a PET substrate layer 3 from top to bottom.

[0025] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0026] Example 1 A polyacrylate adhesive with high cohesion and low displacement comprises the following raw materials in percentage by weight: 30% of acrylate hard monomer, 15% of acrylate soft monomer, 1% of modified monomer, 0.1% of initiator, and 53.9% of organic solvent.

[0027] The preparation method of the high cohesion and low displacement polyacrylate adhesive comprises the following steps: (1) Weigh 2 / 3 of the acrylate soft monomer, 2 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and a solvent to obtain a mixed monomer A; and uniformly mix the remaining 1 / 3 of the acrylate soft monomer, 1 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and an initiator to obtain a mixed monomer B; (2) Add the mixed monomer A into the reactor at one time, heat it in a water bath to 60°C, and introduce nitrogen to expel the air; add the mixed monomer B into the funnel and drop it into the mixed monomer A at a uniform speed, while stirring it at a speed of 200 r / min with a polytetrafluoroethylene stirring paddle to allow it to react fully, and control the dropwise addition time of the mixed monomer B to be 3 hours; (3) After the addition of the mixed monomers is completed, the reactor temperature is maintained at 60°C and the reaction is continued for 6 hours. The polymer is then cooled to room temperature to obtain a polyacrylate adhesive.

[0028] Example 2 A polyacrylate adhesive with high cohesion and low displacement comprises the following raw materials in percentage by weight: 20% of acrylate hard monomer, 10% of acrylate soft monomer, 5% of modified monomer, 0.5% of initiator, and 64.5% of organic solvent.

[0029] The preparation method of the polyacrylate adhesive is the same as that in Example 1.

[0030] Example 3 A polyacrylate adhesive with high cohesion and low displacement comprises the following raw materials in percentage by weight: 21% of acrylate hard monomer, 10.5% of acrylate soft monomer, 3.1% of modified monomer, 0.4% of initiator, and 65% of organic solvent.

[0031] The preparation method of the polyacrylate adhesive is the same as that in Example 1.

[0032] Example 4 A polyacrylate adhesive with high cohesion and low displacement comprises the following raw materials in percentage by weight: 29.8% of acrylate hard monomer, 14.9% of acrylate soft monomer, 4.85% of modified monomer, 0.45% of initiator, and 50% of organic solvent.

[0033] The preparation method of the high cohesion and low displacement polyacrylate adhesive comprises the following steps: (1) Weigh 2 / 3 of the acrylate soft monomer, 2 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and a solvent to obtain a mixed monomer A; and uniformly mix the remaining 1 / 3 of the acrylate soft monomer, 1 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and an initiator to obtain a mixed monomer B; (2) Add the mixed monomer A into the reactor at one time, heat it to 80°C in a water bath, and introduce nitrogen to expel the air; add the mixed monomer B into the funnel and drop it into the mixed monomer A at a uniform speed, while stirring it at a speed of 200 r / min with a polytetrafluoroethylene stirring paddle to allow it to react fully, and control the dropwise addition time of the mixed monomer B to be 2 h; (3) After the addition of the mixed monomers is completed, the reactor temperature is maintained at 80°C and the reaction is continued for 4 hours. The polymer is then cooled to room temperature to obtain a polyacrylate adhesive.

[0034] Example 5 A method for preparing a polyacrylate pressure-sensitive adhesive tape comprises the following steps: A. The polyacrylate adhesive obtained in Examples 1 to 4 is mixed with a curing agent, a catalyst, a petroleum resin, and a solvent and stirred to obtain a mixed adhesive; B. coating the mixed adhesive prepared in step A on the corona surface of the PET film to form a pressure-sensitive adhesive layer; C. Pull the PET film coated with the pressure-sensitive adhesive layer at a speed of 5 mm / s. After pulling, bake it at 110°C for 4 minutes; D. Laminating a layer of silicone oil release film on the baked pressure-sensitive adhesive layer, and then curing in a 50°C oven for 2 days. After curing, a polyacrylate pressure-sensitive adhesive tape is obtained.

[0035] Example 6 A method for preparing a polyacrylate pressure-sensitive adhesive tape comprises the following steps: A. The polyacrylate adhesive obtained in Examples 1 to 4 was mixed with a curing agent, a catalyst, a rosin resin, and a solvent and stirred to obtain a mixed adhesive; B. coating the mixed adhesive prepared in step A on the corona surface of the PET film to form a pressure-sensitive adhesive layer; C. Pull the PET film coated with the pressure-sensitive adhesive layer at a speed of 5 mm / s. After pulling, bake it at 110°C for 4 minutes; D. Compounding a layer of silicone oil release film on the baked pressure-sensitive adhesive layer, and then placing it in a 50° C. oven for aging for 2 days. After aging, a polyacrylate pressure-sensitive adhesive tape is obtained.

[0036] Test Case The polyacrylate pressure-sensitive adhesive tapes prepared in Examples 5 and 6 were subjected to a peel strength test, a tack retention test, and a hot and cold cycle test. The results are shown in Table 1.

[0037] Table 1 Performance test results of polyacrylate pressure-sensitive adhesive tapes prepared in Examples 5 to 6 It can be seen from the above test results that the polyacrylate pressure-sensitive adhesive tape prepared by the present invention has strong overall cohesion, and basically no displacement after bonding, stable bonding performance, can meet the reliability requirements under complex working conditions, and can be used for high-viscosity pressure-sensitive adhesives.

[0038] The above embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patented invention. It should be noted that those skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention. These variations and improvements are equivalent modifications and improvements to the above embodiments based on the essential technology of the present invention and fall within the scope of protection of the present invention.

Claims

1. A polyacrylate adhesive with high cohesion and low displacement, characterized in that: The invention comprises the following raw materials in weight percentage: 20%-30% acrylate hard monomer, 10%-15% acrylate soft monomer, 1%-5% modified monomer, 0.1%-0.5% initiator, and 50%-65% organic solvent; The preparation method of the high cohesion and low displacement polyacrylate adhesive comprises the following steps: (1) Weigh 2 / 3 of the acrylate soft monomer, 2 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and a solvent to obtain a mixed monomer A; and uniformly mix the remaining 1 / 3 of the acrylate soft monomer, 1 / 3 of the acrylate hard monomer, 1 / 2 of the modified monomer and an initiator to obtain a mixed monomer B; (2) Add the mixed monomer A into the reactor at one time, heat it in a water bath to 60-80°C, and introduce nitrogen to expel the air; add the mixed monomer B into the funnel and drop it into the mixed monomer A at a uniform speed, while stirring it at a speed of 200 r / min with a polytetrafluoroethylene stirring paddle to allow it to react fully, and control the dropwise addition time of the mixed monomer B to be 2-3 hours; (3) After the addition of the mixed monomers is completed, the temperature of the reactor is maintained at 60-80°C and the reaction is continued for 4-6 hours. The polymer is then cooled to room temperature to obtain a polyacrylate adhesive.

2. The polyacrylate adhesive with high cohesion and low displacement according to claim 1, characterized in that: The modified monomer includes one or a combination of a monomer containing a carboxyl functional group and a monomer containing an amide group.

3. The polyacrylate adhesive with high cohesion and low displacement according to claim 2, characterized in that: The carboxyl functional group-containing monomer includes one or more of methacrylic acid and acrylic acid.

4. The polyacrylate adhesive with high cohesion and low displacement according to claim 2, characterized in that: The amide group-containing monomer includes ammonium acrylate.

5. A method for preparing a polyacrylate pressure-sensitive adhesive tape, characterized in that: The raw materials for preparation include the high cohesion and low displacement polyacrylate adhesive according to any one of claims 1 to 4; The preparation method of the polyacrylate pressure-sensitive adhesive tape comprises the following steps: A. preparing a polyacrylate adhesive, mixing the polypropylene carboxylate adhesive with a curing agent, a catalyst, a tackifying resin, and a solvent and stirring the mixture to obtain a mixed adhesive; B. coating the mixed adhesive prepared in step A on the corona surface of the PET film to form a pressure-sensitive adhesive layer; C. Pull the PET film coated with the pressure-sensitive adhesive layer at a speed of 5 mm / s. After pulling, bake it at 110°C for 3-5 minutes; D. Laminating a layer of silicone oil release film on the baked pressure-sensitive adhesive layer, and then curing in a 50°C oven for 2 days. After curing, a polyacrylate pressure-sensitive adhesive tape is obtained.

6. A polyacrylate pressure-sensitive adhesive tape, characterized in that: The polyacrylate pressure-sensitive adhesive tape is prepared by the preparation method of the polyacrylate pressure-sensitive adhesive tape according to claim 5. The polyacrylate pressure-sensitive adhesive tape comprises, from top to bottom, a silicone oil release layer, a polyacrylate pressure-sensitive adhesive layer and a PET substrate layer.

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