Double-sided adhesive tape with excellent weather resistance and preparation method thereof

Abstract

The invention relates to the technical field of adhesive tapes, and specifically discloses a double-sided adhesive tape with excellent weather resistance and a preparation method thereof. The double-sided adhesive tape comprises a first release film layer, a first adhesive layer, a substrate layer, a second adhesive layer, and a second release film layer. The adhesive layer is made of an adhesive through simple processes such as coating and drying, and is easy to be industrially produced. The adhesive is obtained by mixing an acrylic polymer, modified polyvinyl alcohol, a defoamer, and a plasticizer. The acrylic polymer and the modified polyvinyl alcohol have excellent adhesion and can be firmly adhered to various materials. The adhesive raw materials are complementary in structure to form a stable composite system. Through chemical bonding and physical action, the comprehensive performance of the double-sided adhesive tape is further improved. The double-sided adhesive tape has excellent toughness and stability, is not easy to age and fall off, and has improved weather resistance, adhesion, and tensile strength, so that the double-sided adhesive tape is more durable during use.

Description

Technical Field

[0001] The invention relates to the technical field of adhesive tapes, in particular to a double-sided adhesive tape with excellent weather resistance and a preparation method thereof. Background Art

[0002] As an important connection material, double-sided tape not only simplifies the assembly process and improves production efficiency, but also reduces the use of mechanical fasteners, thereby reducing costs and weight. Double-sided tape mainly consists of a base material, an adhesive and a release paper. Among them, the adhesive is the key to the bonding function of the double-sided tape, which determines the key performance indicators of the tape such as adhesion to the adherend, peel strength and weather resistance. With the rapid development of double-sided tape, it has been widely used in many fields such as electronic products, furniture assembly, and automobile manufacturing. Especially in the field of electronic products, electronic products are developing in the direction of miniaturization and integration, and the performance requirements for double-sided tape are also increasing.

[0003] Double-sided tapes often need to face various complex environmental conditions during use, such as high temperature, low temperature, humidity, ultraviolet radiation, etc. These environmental factors will affect the performance of the tape, resulting in problems such as decreased bonding strength, accelerated aging, and shedding, thereby affecting its use effect and service life. Chinese patent application CN106047213A discloses a PET double-sided tape, which includes an outermost PET film layer, an intermediate adhesive layer, and an inner substrate layer. The substrate layer is interwoven with basalt fiber and glass fiber, and the adhesive layer is acrylic adhesive. It has the advantages of no residual glue, no warping, no shrinkage, and high temperature resistance, but poor weather resistance and general adhesion. Chinese patent application CN103013373A discloses an acid-base resistant and high temperature resistant double-sided tape and a method for making the same. The double-sided tape includes a substrate and a first adhesive layer and a second adhesive layer coated on two surfaces of the substrate. The tape has good acid-base resistance, a certain degree of high temperature resistance, and high production efficiency, but its peel strength is low and the initial adhesion is general.

[0004] Therefore, developing a double-sided tape with excellent weather resistance is of great significance for adapting to complex and changeable environmental conditions, maintaining stable performance, and expanding a broad application market. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the present invention provides a double-sided adhesive tape with excellent weather resistance and a preparation method thereof, which solves the general problems of the adhesion and weather resistance of the double-sided adhesive tape.

[0007] (II) Technical solution

[0008] In order to achieve the above object, the present invention discloses a double-sided adhesive tape with excellent weather resistance, comprising a first release film layer, a first adhesive layer, a substrate layer, a second adhesive layer, and a second release film layer;

[0009] The first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence;

[0010] The first adhesive layer and the second adhesive layer have the same composition and are both obtained by coating with an adhesive;

[0011] The thickness of the first adhesive layer is 8-12 μm, and the thickness of the second adhesive layer is 8-12 μm;

[0012] The substrate layer is made of polyimide and has a thickness of 10-20 μm.

[0013] Preferably, the first release film layer and the second release film layer are both release films having the same composition, and are both PET release films.

[0014] Preferably, the preparation method of the adhesive comprises the following steps:

[0015] S1. Ultrasonically disperse graphene oxide in anhydrous toluene. After uniform dispersion, heat up in a nitrogen atmosphere, add toluene-2,4-diisocyanate and a catalyst dibutyltin dilaurate, stir and mix, react, and after the reaction is completed, filter, wash with toluene, and vacuum dry at 60° C. for 24 h to obtain isocyanate-modified graphene oxide;

[0016] S2, stirring and mixing N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and catalyst dibutyltin dilaurate, heating in a nitrogen atmosphere, reacting, after the reaction is completed, filtering, washing with ethanol, and vacuum drying at 60° C. for 24 h to obtain modified polyvinyl alcohol;

[0017] S3, mixing a mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, 2-ethylhexyl acrylate, acrylamide, and an initiator, heating in a nitrogen atmosphere, stirring and mixing, reacting, and obtaining an acrylic polymer after the reaction is completed;

[0018] S4. Evenly mix the acrylic polymer, modified polyvinyl alcohol, defoamer and plasticizer at 40-50° C., and discharge the mixture to obtain an adhesive.

[0019] Preferably, the mass ratio of graphene oxide, anhydrous toluene, toluene-2,4-diisocyanate and dibutyltin dilaurate in S1 is 100:8000-9000:130-150:0.8-1.2.

[0020] Preferably, the reaction temperature in S1 is 70-80° C., and the reaction time is 4-6 h.

[0021] Preferably, the mass ratio of N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and dibutyltin dilaurate in S2 is 3500-4200:100:18-25:0.5-1.

[0022] Preferably, the reaction temperature in S2 is 85-95° C., and the reaction time is 2-4 h.

[0023] Preferably, the specific preparation method of the acrylic polymer in S3 comprises the following steps: mixing one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, and 2-ethylhexyl acrylate with a mixed solvent, wherein the mixed solvent consists of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stirring and mixing evenly, heating to 80°C, adding one-half of the initiator, stirring, reacting for 1-2 hours, then adding the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, and acrylamide, dropping the remaining initiator, stirring and mixing, keeping warm, reacting for 3-5 hours, and after the reaction is completed, cooling to obtain an acrylic polymer.

[0024] Preferably, the mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, acrylamide, and initiator in S3 is 600-900:100:18-25:20-30:10-15:30-40:5-9:3-5:4-9:1-1.5.

[0025] Preferably, the initiator in S3 is benzoyl peroxide.

[0026] Preferably, the preparation method of the olefinic silica in S3 is as follows: ultrasonically disperse nano-silica in a 75% ethanol solution, and after uniform dispersion, add γ-methacryloxypropyltrimethoxysilane, wherein the mass ratio of nano-silica, ethanol solution, and γ-methacryloxypropyltrimethoxysilane is 100:1500:42, and adjust the pH to 4 with hydrochloric acid solution, stir and mix, react at 75°C for 6h, and after the reaction is completed, filter, wash with anhydrous ethanol and deionized water respectively, and dry at 80°C for 12h to obtain olefinic silica.

[0027] Preferably, the mass ratio of the acrylic polymer, modified polyvinyl alcohol, defoamer and plasticizer in S4 is 100:5-9:0.3-0.5:1-1.5.

[0028] Preferably, the defoaming agent in S4 is polydimethylsiloxane.

[0029] Preferably, the plasticizer in S4 is dibutyl phthalate.

[0030] A method for preparing a double-sided tape with excellent weather resistance comprises the following steps: coating an adhesive on a first release film, drying at 85-115°C for 300-360s, forming a first adhesive layer on the first release film layer, compounding with a substrate layer to obtain a double-sided tape semi-finished product; coating an adhesive on a second release film, drying at 85-115°C for 300-360s, forming a second adhesive layer on the second release film layer, compounding with the double-sided tape semi-finished product, and then placing in a 40°C circulating air oven for 48h to obtain a double-sided tape with excellent weather resistance.

[0031] 3. Beneficial technical effects

[0032] In the present invention, toluene-2,4-diisocyanate is used to modify graphene oxide, and isocyanate groups are introduced into the surface of graphene oxide to obtain isocyanate-modified graphene oxide, and the isocyanate groups on the isocyanate-modified graphene oxide react with hydroxyl groups on polyvinyl alcohol to obtain modified polyvinyl alcohol. Acrylic monomers, olefinic silica, and 4-propyleneoxy-2-hydroxybenzophenone are mixed, and acrylamide is used as an internal cross-linking agent. Under the action of an initiator, a polymerization reaction occurs to obtain an acrylic polymer, and the acrylic polymer, modified polyvinyl alcohol, a defoamer, and a plasticizer are mixed to obtain an adhesive.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The double-sided tape of the present invention comprises a first release film layer, a first adhesive layer, a substrate layer, a second adhesive layer, and a second release film layer, and the adhesive layer is obtained by coating an adhesive. Graphene oxide has a high specific surface area and a two-dimensional sheet structure, which can effectively improve the mechanical properties and durability of the adhesive. At the same time, graphene oxide has excellent thermal conductivity, which helps the double-sided tape to quickly dissipate heat in electronic devices and avoid performance degradation caused by local overheating. Graphene oxide is modified and isocyanate groups are introduced to improve the compatibility and reactivity of graphene with the polymer matrix, effectively avoid agglomeration, and enhance the strength and weather resistance of the adhesive. Polyvinyl alcohol has good flexibility and film-forming properties, and forms a continuous film in the adhesive, which is beneficial to improving the mechanical properties and adhesion of the adhesive. Graphene oxide and polyvinyl alcohol are reacted and mixed with acrylic polymers, which can form a hydrogen bond network with the active functional groups in the acrylic polymers, thereby improving the overall strength and creep resistance of the adhesive layer. Nano-silicon dioxide, as a rigid ion, can be dispersed in acrylic polymers through polymerization, and can be evenly dispersed to improve the hardness, compression resistance and wear resistance of the adhesive layer. At the same time, it can adjust the viscosity and thixotropy of the adhesive and improve the coating processability. Acrylic polymers can provide rapid adhesion and lasting adhesion. Their stable chemical structure can resist ultraviolet rays, oxidation and temperature and humidity changes. At the same time, the introduction of ultraviolet absorber 4-propyleneoxy-2-hydroxybenzophenone and nano-silicon dioxide also have excellent ultraviolet shielding effect, ensuring that the tape has excellent weather resistance.

[0035] (2) The acrylic polymer and modified polyvinyl alcohol in the adhesive layer of the present invention have excellent adhesion and can be firmly attached to various materials. Graphene oxide and nano-silicon dioxide work synergistically to form a multi-dimensional reinforcement network in the adhesive matrix, which has excellent physical reinforcement effect and effectively improves the overall mechanical properties of the adhesive. Both have excellent high temperature resistance, water resistance, and aging resistance, which can effectively improve the weather resistance of the adhesive. The flexible segments in acrylic polymers and polyvinyl alcohol complement the rigid structures of graphene oxide and nano-silicon dioxide to form a stable composite system. Through chemical bonding and physical action, the comprehensive performance of the double-sided tape is further improved. It has excellent toughness and stability, is not easy to age or fall off, and has improved weather resistance, adhesion, and tensile strength, making the double-sided tape more durable during use. The polyimide substrate layer has high mechanical strength and high heat resistance, and the tape can maintain stable performance under high temperature, low temperature and harsh environment. The PET release film can protect the adhesive layer and prevent it from being contaminated or damaged during transportation and storage. Furthermore, a double-sided adhesive tape with excellent weather resistance can be prepared through simple processes such as coating and drying, which is easy to industrialize. DETAILED DESCRIPTION

[0036] In order to facilitate the understanding of the present invention, the present invention will be described more fully below. Preferred embodiments of the present invention are given below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0037] Embodiment 1, a method for preparing a double-sided adhesive tape with excellent weather resistance, comprising the following steps:

[0038] The adhesive is coated on the first release film, and dried at 85°C for 360 seconds to form a first adhesive layer on the first release film layer, the thickness of the first adhesive layer is 8 μm, and it is compounded with the substrate layer, wherein the substrate layer is made of polyimide material with a thickness of 10 μm, to obtain a double-sided tape semi-finished product; the adhesive is coated on the second release film, and dried at 85°C for 360 seconds to form a second adhesive layer on the second release film layer, the thickness of the second adhesive layer is 8 μm, and it is compounded with the double-sided tape semi-finished product, and then placed in a 40°C circulating air oven for 48 hours, wherein the first adhesive layer and the second adhesive layer have the same composition, and the first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence to obtain a double-sided tape with excellent weather resistance.

[0039] The preparation method of the adhesive comprises the following steps:

[0040] S1. Ultrasonically disperse graphene oxide in anhydrous toluene. After uniform dispersion, heat up in a nitrogen atmosphere, add toluene-2,4-diisocyanate and dibutyltin dilaurate, wherein the mass ratio of the added graphene oxide, anhydrous toluene, toluene-2,4-diisocyanate, and dibutyltin dilaurate is 100:8000:130:0.8, stir and mix, react at 70°C for 6 hours, and after the reaction is completed, filter, wash with toluene, and vacuum dry at 60°C for 24 hours to obtain isocyanate-modified graphene oxide;

[0041] S2, mixing N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and dibutyltin dilaurate in a mass ratio of 3500:100:18:0.5, heating in a nitrogen atmosphere, reacting at 85°C for 4 hours, and after the reaction, filtering, washing with ethanol, and vacuum drying at 60°C for 24 hours to obtain modified polyvinyl alcohol;

[0042] S3, mix one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate with a mixed solvent, wherein the mixed solvent is composed of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stir and mix evenly, heat to 80°C, add one-half of the initiator, stir, react for 1 hour, then add the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and olefinated silica, 4-propyleneoxy-2- hydroxybenzophenone, acrylamide, and the remaining initiator are added dropwise, wherein the mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, acrylamide, and initiator is 600:100:18:20:10:30:5:3:4:1, and the initiator is benzoyl peroxide, stirring and mixing, keeping warm, reacting for 3 hours, and cooling after the reaction is completed to obtain an acrylic polymer;

[0043] S4. Mix the acrylic polymer, modified polyvinyl alcohol, defoaming agent polydimethylsiloxane, and plasticizer dibutyl phthalate in a mass ratio of 100:5:0.3:1 at 40° C. and discharge the mixture to obtain an adhesive.

[0044] Embodiment 2, a method for preparing a double-sided adhesive tape with excellent weather resistance, comprising the following steps:

[0045] The adhesive is coated on the first release film, and dried at 95°C for 320 seconds to form a first adhesive layer on the first release film layer, the thickness of the first adhesive layer is 10 μm, and it is compounded with the substrate layer, wherein the substrate layer is made of polyimide material with a thickness of 15 μm, to obtain a double-sided tape semi-finished product; the adhesive is coated on the second release film, and dried at 95°C for 320 seconds to form a second adhesive layer on the second release film layer, the thickness of the second adhesive layer is 10 μm, and it is compounded with the double-sided tape semi-finished product, and then placed in a 40°C circulating air oven for 48 hours, wherein the first adhesive layer and the second adhesive layer have the same composition, and the first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence to obtain a double-sided tape with excellent weather resistance.

[0046] The preparation method of the adhesive comprises the following steps:

[0047] S1. Ultrasonically disperse graphene oxide in anhydrous toluene. After uniform dispersion, heat up in a nitrogen atmosphere, add toluene-2,4-diisocyanate and dibutyltin dilaurate, wherein the mass ratio of the added graphene oxide, anhydrous toluene, toluene-2,4-diisocyanate, and dibutyltin dilaurate is 100:8400:135:0.9, stir and mix, react at 75°C for 5 hours, and after the reaction is completed, filter, wash with toluene, and vacuum dry at 60°C for 24 hours to obtain isocyanate-modified graphene oxide;

[0048] S2, mixing N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and dibutyltin dilaurate in a mass ratio of 3800:100:21:0.6, heating in a nitrogen atmosphere, reacting at 90°C for 3 hours, and after the reaction, filtering, washing with ethanol, and vacuum drying at 60°C for 24 hours to obtain modified polyvinyl alcohol;

[0049] S3, mix one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate with a mixed solvent, wherein the mixed solvent is composed of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stir and mix evenly, heat to 80°C, add one-half of the initiator, stir, react for 1.5 hours, then add the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and olefinic silica, 4-propyleneoxy-2-hydroxy benzophenone, acrylamide, and the remaining initiator are added dropwise, wherein the mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, acrylamide, and the initiator is 700:100:21:24:12:34:6:3.5:6:1.2, and the initiator is benzoyl peroxide, stirring and mixing, keeping warm, reacting for 4 hours, and after the reaction is completed, cooling to obtain an acrylic polymer;

[0050] S4. Mix the acrylic polymer, modified polyvinyl alcohol, defoaming agent polydimethylsiloxane, and plasticizer dibutyl phthalate in a mass ratio of 100:6:0.4:1.2 at 45° C. and discharge the mixture to obtain an adhesive.

[0051] Embodiment 3, a method for preparing a double-sided adhesive tape with excellent weather resistance, comprising the following steps:

[0052] The adhesive is coated on the first release film, and dried at 95°C for 320 seconds to form a first adhesive layer on the first release film layer, the thickness of the first adhesive layer is 10 μm, and it is compounded with the substrate layer, wherein the substrate layer is made of polyimide material with a thickness of 15 μm, to obtain a double-sided tape semi-finished product; the adhesive is coated on the second release film, and dried at 95°C for 320 seconds to form a second adhesive layer on the second release film layer, the thickness of the second adhesive layer is 10 μm, and it is compounded with the double-sided tape semi-finished product, and then placed in a 40°C circulating air oven for 48 hours, wherein the first adhesive layer and the second adhesive layer have the same composition, and the first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence to obtain a double-sided tape with excellent weather resistance.

[0053] The preparation method of the adhesive comprises the following steps:

[0054] S1. Ultrasonically disperse graphene oxide in anhydrous toluene. After uniform dispersion, heat up in a nitrogen atmosphere, add toluene-2,4-diisocyanate and dibutyltin dilaurate, wherein the mass ratio of the added graphene oxide, anhydrous toluene, toluene-2,4-diisocyanate, and dibutyltin dilaurate is 100:8400:145:1, stir and mix, react at 75°C for 5 hours, and after the reaction is completed, filter, wash with toluene, and vacuum dry at 60°C for 24 hours to obtain isocyanate-modified graphene oxide;

[0055] S2, mixing N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and dibutyltin dilaurate in a mass ratio of 4000:100:24:0.8, heating in a nitrogen atmosphere, reacting at 90°C for 3 hours, and after the reaction, filtering, washing with ethanol, and vacuum drying at 60°C for 24 hours to obtain modified polyvinyl alcohol;

[0056] S3, mix one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate with a mixed solvent, wherein the mixed solvent is composed of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stir and mix evenly, heat to 80°C, add one-half of the initiator, stir, react for 1.5 hours, then add the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and olefinic silica, 4-propyleneoxy-2-hydroxy Benzophenone, acrylamide, and the remaining initiator are added dropwise, wherein the mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, acrylamide, and initiator is 700:100:24:28:14:36:7:4.2:8:1.4, and the initiator is benzoyl peroxide, stirring and mixing, keeping warm, reacting for 4.5 hours, and cooling after the reaction is completed to obtain an acrylic polymer;

[0057] S4. Mix the acrylic polymer, modified polyvinyl alcohol, defoaming agent polydimethylsiloxane, and plasticizer dibutyl phthalate in a mass ratio of 100:8:0.4:1.2 at 45° C. and discharge the mixture to obtain an adhesive.

[0058] Embodiment 4, a method for preparing a double-sided adhesive tape with excellent weather resistance, comprising the following steps:

[0059] The adhesive is coated on the first release film, and dried at 105°C for 340 seconds to form a first adhesive layer on the first release film layer, the thickness of the first adhesive layer is 11 μm, and it is compounded with the substrate layer, wherein the substrate layer is made of polyimide material with a thickness of 15 μm, to obtain a double-sided tape semi-finished product; the adhesive is coated on the second release film, and dried at 105°C for 320 seconds to form a second adhesive layer on the second release film layer, the thickness of the second adhesive layer is 11 μm, and it is compounded with the double-sided tape semi-finished product, and then placed in a circulating air oven at 40°C for 48 hours, wherein the first adhesive layer and the second adhesive layer have the same composition, and the first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence to obtain a double-sided tape with excellent weather resistance.

[0060] The preparation method of the adhesive is the same as the preparation method of the adhesive in Example 3.

[0061] Embodiment 5, a method for preparing a double-sided adhesive tape with excellent weather resistance, comprising the following steps:

[0062] The adhesive is coated on the first release film, dried at 115°C for 300s, and a first adhesive layer is formed on the first release film layer, the thickness of the first adhesive layer is 12μm, and it is compounded with the substrate layer, wherein the substrate layer is made of polyimide material with a thickness of 20μm, to obtain a double-sided tape semi-finished product; the adhesive is coated on the second release film, dried at 115°C for 300s, and a second adhesive layer is formed on the second release film layer, the thickness of the second adhesive layer is 12μm, and it is compounded with the double-sided tape semi-finished product, and then placed in a 40°C circulating air oven for 48h, wherein the first adhesive layer and the second adhesive layer have the same composition, and the first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence to obtain a double-sided tape with excellent weather resistance.

[0063] The preparation method of the adhesive comprises the following steps:

[0064] S1. Ultrasonically disperse graphene oxide in anhydrous toluene. After uniform dispersion, heat up in a nitrogen atmosphere, add toluene-2,4-diisocyanate and dibutyltin dilaurate, wherein the mass ratio of the added graphene oxide, anhydrous toluene, toluene-2,4-diisocyanate, and dibutyltin dilaurate is 100:9000:150:1.2, stir and mix, react at 80°C for 4 hours, and after the reaction is completed, filter, wash with toluene, and vacuum dry at 60°C for 24 hours to obtain isocyanate-modified graphene oxide;

[0065] S2, mixing N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and dibutyltin dilaurate in a mass ratio of 4200:100:25:1, heating in a nitrogen atmosphere, reacting at 95°C for 2 hours, and after the reaction, filtering, washing with ethanol, and vacuum drying at 60°C for 24 hours to obtain modified polyvinyl alcohol;

[0066] S3, mix one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate with a mixed solvent, wherein the mixed solvent is composed of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stir and mix evenly, heat to 80°C, add one-half of the initiator, stir, react for 2 hours, then add the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and olefinic silica, 4-propyleneoxy-2-hydroxy benzophenone, acrylamide, and the remaining initiator are added dropwise, wherein the mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, acrylamide, and the initiator is 900:100:25:30:15:40:9:5:9:1.5, and the initiator is benzoyl peroxide, stirring and mixing, keeping warm, reacting for 5 hours, and cooling after the reaction to obtain an acrylic polymer;

[0067] S4. Mix the acrylic polymer, modified polyvinyl alcohol, defoaming agent polydimethylsiloxane, and plasticizer dibutyl phthalate in a mass ratio of 100:9:0.5:1.5 at 50° C. and discharge the mixture to obtain an adhesive.

[0068] Comparative Example 1, a method for preparing a double-sided adhesive tape, comprising the following steps:

[0069] The adhesive is coated on the first release film, and dried at 105°C for 340 seconds to form a first adhesive layer on the first release film layer, the thickness of the first adhesive layer is 11 μm, and it is compounded with the substrate layer, wherein the substrate layer is made of polyimide material with a thickness of 15 μm, to obtain a double-sided tape semi-finished product; the adhesive is coated on the second release film, and dried at 105°C for 320 seconds to form a second adhesive layer on the second release film layer, the thickness of the second adhesive layer is 11 μm, and it is compounded with the double-sided tape semi-finished product, and then placed in a circulating air oven at 40°C for 48 hours, wherein the first adhesive layer and the second adhesive layer have the same composition, and the first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence to obtain a double-sided tape.

[0070] The preparation method of the adhesive comprises the following steps:

[0071] S1. Mix one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and a mixed solvent, wherein the mixed solvent is composed of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stir and mix evenly, heat to 80°C, add one-half of the initiator, stir, react for 1.5 hours, then add the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and olefinated silica, 4-propyleneoxy-2-hydroxy Benzophenone, acrylamide, and the remaining initiator are added dropwise, wherein the mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, acrylamide, and initiator is 700:100:24:28:14:36:7:4.2:8:1.4, and the initiator is benzoyl peroxide, stirring and mixing, keeping warm, reacting for 4.5 hours, and cooling after the reaction is completed to obtain an acrylic polymer;

[0072] S2. Evenly mix acrylic polymer, graphene oxide, polyvinyl alcohol, defoaming agent polydimethylsiloxane, and plasticizer dibutyl phthalate in a mass ratio of 100:1.5:6.5:0.4:1.2 at 45° C., discharge the mixture, and obtain an adhesive.

[0073] Comparative Example 2, a method for preparing a double-sided adhesive tape, comprising the following steps:

[0074] The adhesive is coated on the first release film, and dried at 105°C for 340 seconds to form a first adhesive layer on the first release film layer, the thickness of the first adhesive layer is 11 μm, and it is compounded with the substrate layer, wherein the substrate layer is made of polyimide material with a thickness of 15 μm, to obtain a double-sided tape semi-finished product; the adhesive is coated on the second release film, and dried at 105°C for 320 seconds to form a second adhesive layer on the second release film layer, the thickness of the second adhesive layer is 11 μm, and it is compounded with the double-sided tape semi-finished product, and then placed in a circulating air oven at 40°C for 48 hours, wherein the first adhesive layer and the second adhesive layer have the same composition, and the first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence to obtain a double-sided tape.

[0075] The preparation method of the adhesive comprises the following steps:

[0076] S1. Ultrasonically disperse graphene oxide in anhydrous toluene. After uniform dispersion, heat up in a nitrogen atmosphere, add toluene-2,4-diisocyanate and dibutyltin dilaurate, wherein the mass ratio of the added graphene oxide, anhydrous toluene, toluene-2,4-diisocyanate, and dibutyltin dilaurate is 100:8400:145:1, stir and mix, react at 75°C for 5 hours, and after the reaction is completed, filter, wash with toluene, and vacuum dry at 60°C for 24 hours to obtain isocyanate-modified graphene oxide;

[0077] S2, mixing N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and dibutyltin dilaurate in a mass ratio of 4000:100:24:0.8, heating in a nitrogen atmosphere, reacting at 90°C for 3 hours, and after the reaction, filtering, washing with ethanol, and vacuum drying at 60°C for 24 hours to obtain modified polyvinyl alcohol;

[0078] S3, mix one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate with a mixed solvent, wherein the mixed solvent is composed of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stir and mix evenly, heat to 80°C, add one-half of the initiator, stir, react for 1.5 hours, then add the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, 4-propyleneoxy-2-hydroxybenzophenone and acrylamide, and dropwise add the remaining initiator, wherein the mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, 4-propyleneoxy-2-hydroxybenzophenone, acrylamide, and initiator is 700:107:24:28:14:36:4.2:8:1.4, and the initiator is benzoyl peroxide, stir and mix, keep warm, react for 4.5 hours, and after the reaction is completed, cool to obtain an acrylic polymer;

[0079] S4. Mix acrylic polymer, nano-silica, modified polyvinyl alcohol, defoaming agent polydimethylsiloxane, and plasticizer dibutyl phthalate in a mass ratio of 97:3:8:0.4:1.2 at 45° C. and discharge the mixture to obtain an adhesive.

[0080] Comparative Example 3, a method for preparing a double-sided tape, comprising the following steps:

[0081] The adhesive is coated on the first release film, and dried at 105°C for 340 seconds to form a first adhesive layer on the first release film layer, the thickness of the first adhesive layer is 11 μm, and it is compounded with the substrate layer, wherein the substrate layer is made of polyimide material with a thickness of 15 μm, to obtain a double-sided tape semi-finished product; the adhesive is coated on the second release film, and dried at 105°C for 320 seconds to form a second adhesive layer on the second release film layer, the thickness of the second adhesive layer is 11 μm, and it is compounded with the double-sided tape semi-finished product, and then placed in a circulating air oven at 40°C for 48 hours, wherein the first adhesive layer and the second adhesive layer have the same composition, and the first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence to obtain a double-sided tape.

[0082] The preparation method of the adhesive comprises the following steps:

[0083] S1. Mix one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and a mixed solvent, wherein the mixed solvent is composed of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stir and mix evenly, heat to 80°C, add one-half of the initiator, stir, react for 1.5 hours, then add the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and acrylamide, and dropwise add the remaining initiator, wherein the mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, acrylamide, and initiator is 700:100:24:28:14:36:8:1.4, and the initiator is benzoyl peroxide, stir and mix, keep warm, react for 4.5 hours, and after the reaction is completed, cool to obtain an acrylic polymer;

[0084] S2. Mix acrylic polymer, nano silicon dioxide, graphene oxide, polyvinyl alcohol, defoaming agent polydimethylsiloxane, and plasticizer dibutyl phthalate in a mass ratio of 97:3:1.5:6.5:0.4:1.2 at 45° C. and discharge the mixture to obtain an adhesive.

[0085] The preparation method of olefinated silica in the embodiments and comparative examples of the present invention is as follows: nano-silica is ultrasonically dispersed in a 75% ethanol solution, and after uniform dispersion, γ-methacryloxypropyltrimethoxysilane is added, wherein the mass ratio of nano-silica, ethanol solution, and γ-methacryloxypropyltrimethoxysilane is 100:1500:42, and the pH is adjusted to 4 with a hydrochloric acid solution, and the mixture is stirred and mixed, and reacted at 75° C. for 6 h. After the reaction is completed, the mixture is filtered, washed with anhydrous ethanol and deionized water, respectively, and dried at 80° C. for 12 h to obtain olefinated silica.

[0086] The graphene oxide used in the embodiments and comparative examples of the present invention is multilayer graphene oxide, purchased from Suzhou Hengqiu Technology Co., Ltd., with a purity of >95wt%, a thickness of 3.4-8nm, and a sheet diameter of 10-50μm; nano-silicon dioxide is purchased from Jiangsu Lianyungang Pengrui Chemical Co., Ltd., with a particle size of 15nm; polyvinyl alcohol is 1799 type polyvinyl alcohol, industrial grade, purchased from Sichuan Vinylon Plant of Sinopec Group; other unspecified raw materials and reagents are commercially available.

[0087] The double-sided tapes prepared in Examples 1-5 and Comparative Examples 1-3 were subjected to relevant performance tests, as follows:

[0088] (1) 180° peel strength: refer to GB / T 2792-2014 "Test method for peel strength of adhesive tape" to test the peel strength of the sample using an electronic tensile testing machine;

[0089] (2) Initial tack: measured with CZY-G initial tack tester in accordance with GB / T4852-2002 “Test method for initial tack of pressure-sensitive adhesive tapes (rolling ball method)”;

[0090] (3) Adhesion: The samples were tested for adhesion according to GB / T 4851-2014 “Test method for adhesion of adhesive tapes”. The test was performed using a CZY-S adhesion tester at a test temperature of 50°C and a weight of 500g.

[0091] (4) High temperature resistance: The samples were tested for heat resistance in accordance with GB / T 4851-2014 “Test method for adhesive tape adhesion”. The test was performed using a CZY-S adhesion tester at a test temperature of 120°C and a weight of 500g. When the tape completely fell off (at 100°C) for ≥4h, it was considered to have good high temperature resistance.

[0092] The test results are shown in Table 1:

[0093] Table 1

[0094]

[0095] According to the test results in Table 1, the double-sided tapes corresponding to Examples 1-5 of the present invention show excellent peel strength, and the double-sided tapes can withstand a large force when peeling, and have good adhesion. The initial adhesion and sustained adhesion tests show that they can quickly form a strong adhesion, and have the ability to maintain a stable adhesion. The heat-resistant sustained adhesion test shows that the double-sided tape can still maintain good adhesion under high temperature conditions. In Comparative Example 1, graphene oxide was not modified, and graphene oxide and polyvinyl alcohol were directly added to the adhesive. In Comparative Example 2, nano-silicon dioxide was not modified, and nano-silicon dioxide was directly added to the adhesive. The dispersibility between the raw materials in Comparative Examples 1 and 2 deteriorated, the compatibility decreased, and the comprehensive performance decreased. In Comparative Example 3, graphene oxide and nano-silicon dioxide were directly added, and agglomeration easily occurred in the adhesive matrix, and the heat resistance and adhesion were greatly reduced.

[0096] Although the embodiments of the present invention have been shown and described, it will be understood 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 all equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A double-sided adhesive tape with excellent weather resistance, characterized in that: It includes a first release film layer, a first adhesive layer, a substrate layer, a second adhesive layer, and a second release film layer; The first release film layer, the first adhesive layer, the substrate layer, the second adhesive layer, and the second release film layer are arranged in sequence; The first adhesive layer and the second adhesive layer have the same composition and are both formed by coating with an adhesive; The thickness of the first adhesive layer is 8-12 μm, and the thickness of the second adhesive layer is 8-12 μm; The thickness of the substrate layer is 10-20 μm; The preparation method of the adhesive comprises the following steps: S1. Ultrasonically disperse graphene oxide in anhydrous toluene. After uniform dispersion, heat up in a nitrogen atmosphere, add toluene-2,4-diisocyanate and dibutyltin dilaurate, stir and mix, react, and after the reaction is completed, filter, wash, and vacuum dry at 60° C. for 24 h to obtain isocyanate-modified graphene oxide; S2, stirring and mixing N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and dibutyltin dilaurate, heating in a nitrogen atmosphere, reacting, and after the reaction is completed, filtering, washing, and vacuum drying at 60° C. for 24 h to obtain modified polyvinyl alcohol; S3, mixing a mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, 2-ethylhexyl acrylate, acrylamide, and an initiator, heating the mixture in a nitrogen atmosphere, stirring and mixing the mixture to react, and obtaining an acrylic polymer after the reaction is completed; S4, mixing the acrylic polymer, modified polyvinyl alcohol, defoamer and plasticizer at 40-50° C. and discharging the mixture to obtain an adhesive; The mass ratio of the acrylic polymer, modified polyvinyl alcohol, defoamer and plasticizer in S4 is 100:5-9:0.3-0.5:1-1.

5.

2. The double-sided adhesive tape with excellent weather resistance according to claim 1, characterized in that: The mass ratio of graphene oxide, anhydrous toluene, toluene-2,4-diisocyanate and dibutyltin dilaurate in S1 is 100:8000-9000:130-150:0.8-1.2, the reaction temperature is 70-80° C., and the reaction time is 4-6 h.

3. The double-sided adhesive tape with excellent weather resistance according to claim 1, characterized in that: The mass ratio of N,N-dimethylformamide, polyvinyl alcohol, isocyanate-modified graphene oxide and dibutyltin dilaurate in S2 is 3500-4200:100:18-25:0.5-1, the reaction temperature is 85-95° C., and the reaction time is 2-4 h.

4. The double-sided adhesive tape with excellent weather resistance according to claim 1, characterized in that: The specific preparation method of the acrylic polymer in S3 comprises the following steps: mixing one-fourth of acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate with a mixed solvent, wherein the mixed solvent consists of anhydrous ethanol and ethyl acetate in a volume ratio of 1:1, stirring and mixing evenly, heating to 80°C, adding one-half of the initiator, stirring, reacting for 1-2 hours, then adding the remaining acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate and olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, and acrylamide, dropping the remaining initiator, stirring and mixing, keeping warm, reacting for 3-5 hours, and after the reaction is completed, cooling to obtain the acrylic polymer.

5. The double-sided adhesive tape with excellent weather resistance according to claim 4, characterized in that: The mass ratio of the mixed solvent, acrylic acid, phenyl methacrylate, butyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, olefinated silica, 4-propyleneoxy-2-hydroxybenzophenone, acrylamide and initiator is 600-900:100:18-25:20-30:10-15:30-40:5-9:3-5:4-9:1-1.

5.

6. The double-sided adhesive tape with excellent weather resistance according to claim 1, characterized in that: The initiator in S3 is benzoyl peroxide.

7. The double-sided adhesive tape with excellent weather resistance according to claim 1, characterized in that: The defoamer in S4 is polydimethylsiloxane, and the plasticizer is dibutyl phthalate.

8. A method for preparing a double-sided adhesive tape with excellent weather resistance as claimed in any one of claims 1 to 7, characterized in that: The method comprises the following steps: coating an adhesive on a first release film, drying at 85-115°C for 300-360s, forming a first adhesive layer on the first release film layer, compounding with a substrate layer, and obtaining a double-sided tape semi-finished product; coating an adhesive on a second release film, drying at 85-115°C for 300-360s, forming a second adhesive layer on the second release film layer, compounding with the double-sided tape semi-finished product, and placing in a 40°C circulating air oven for 48h to obtain a double-sided tape with excellent weather resistance.

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