Silicone-modified acrylic pressure-sensitive adhesive, pressure-sensitive adhesive tape and preparation method thereof

Abstract

The invention discloses a silicon-modified acrylic pressure-sensitive adhesive, a pressure-sensitive adhesive tape and a preparation method thereof. The pressure-sensitive adhesive tape comprises an adhesive tape body and release film layers arranged on both sides of the adhesive tape body. The adhesive tape body comprises a first silicon-modified acrylic pressure-sensitive adhesive layer, a first primer layer, a butyl rubber elastomer layer, a second primer layer and a second silicon-modified acrylic pressure-sensitive adhesive layer which are arranged in sequence. The primer layer is directly coated on the butyl rubber elastomer layer. The silicon-modified acrylic pressure-sensitive adhesive layer is adhered and superimposed by the primer layer coated on the butyl rubber elastomer layer. The primer layer has good adhesion to the butyl rubber elastomer layer and can serve as a connecting medium between the silicon-modified acrylic pressure-sensitive adhesive layer and the butyl rubber elastomer layer. The overall thickness is relatively thin, and the adhesive strength, shock absorption effect and impact absorption performance are excellent, and the impact resistance and buffering ability are strong.

Description

Technical Field

[0001] The invention relates to the field of pressure-sensitive adhesive tapes, and in particular to a silicon-modified acrylic pressure-sensitive adhesive, a pressure-sensitive adhesive tape and a preparation method thereof. Background Art

[0002] Due to the many advantages of 0LED, 0LED technology has a wider application range than LCD technology, and can be extended to the fields of electronic products, commerce, transportation, industrial control, and medical applications. With the development of science and technology, people's lives are inseparable from electronic display devices, such as mobile phones and computers: these electronic devices are prone to bumps and falls during use, so it is necessary to stick a layer of buffer material foam under the OLED frame of these electronic devices to absorb the impact of the outside world. Traditional foam materials are divided into PU foam, PE foam, PP foam, EVA foam, etc., which have average impact absorption capacity and need to reach a certain thickness to achieve good buffering performance; and the current market demand is towards ultra-thin and high buffering development, so the development of a thin and high impact absorption buffer material is the future trend. In addition, the current traditional single foam buffer also needs to be combined with mesh double-sided tape, PI tape, and metal support tape to form a buffer layer to achieve a buffering effect, which increases the thickness of the product and the cost of the product. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a silicon-modified acrylic pressure-sensitive adhesive, a pressure-sensitive adhesive tape and a preparation method thereof. The pressure-sensitive adhesive tape made of the silicon-modified acrylic pressure-sensitive adhesive mainly comprises a first silicon-modified acrylic pressure-sensitive adhesive layer, a first primer layer, a butyl rubber elastomer layer, a second primer layer and a second silicon-modified acrylic pressure-sensitive adhesive layer. The pressure-sensitive adhesive tape is relatively thin as a whole, has excellent shock-absorbing effect and impact absorption performance, and has strong impact resistance and buffering ability.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] First, the present invention provides a silicon-modified acrylic pressure-sensitive adhesive, comprising the following raw materials: a hard monomer, a soft monomer, a functional monomer, an initiator, a first solvent and a curing cross-linking agent;

[0006] The soft monomer accounts for 65-90% of the total mass of the monomers, the hard monomer accounts for 9-25% of the total mass of the monomers, the functional monomer accounts for 1-10% of the total mass of the monomers, the initiator is used in an amount of 0.5-2% of the total mass of the monomers, the curing cross-linking agent is used in an amount of 1-3% of the total mass of the monomers, and the ratio of the amount of the solvent to the total mass of the monomers is 1:1;

[0007] The soft monomer is a mixture of 2-(2-ethoxyethoxy) ethyl acrylate (EEA) and 2-hydroxyethyl acrylate (HEA) and at least one of decyl acrylate (OA), butyl acrylate (BA), 2-ethylhexyl acrylate (EHA), and 2-hydroxypropyl acrylate (HPA), wherein the 2-(2-ethoxyethoxy) ethyl acrylate accounts for 30-60% of the total mass of the soft monomer, and the 2-hydroxyethyl acrylate (HEA) accounts for 8-15% of the total mass of the soft monomer;

[0008] The hard monomer is a mixture of α-pinene methacrylate and methyl methacrylate (MMA) and / or methyl acrylate (MA), and the α-pinene methacrylate accounts for 10 to 20% of the total mass of the hard monomer;

[0009] The functional monomer is silane-modified acrylate;

[0010] The initiator is at least one of benzoyl peroxide, azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate, tert-butyl benzoyl peroxide, and methyl ethyl ketone peroxide;

[0011] The curing cross-linking agent is at least one of hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, tetramethyl meta-xylylene diisocyanate and toluene diisocyanate;

[0012] The first solvent is ethyl acetate, xylene or toluene.

[0013] Furthermore, the silane-modified acrylate is prepared by the following method:

[0014] At room temperature, diethylene glycol diacrylate or tetraethylene glycol diacrylate is placed in a reaction container, (3-mercaptopropyl)trimethoxysilane is slowly added dropwise, and after stirring and mixing, a catalyst is added, and the mixture is purified after reaction to obtain a silane-modified acrylate;

[0015] The molar ratio of diethylene glycol diacrylate or tetraethylene glycol diacrylate to (3-mercaptopropyl)trimethoxysilane is 1:1;

[0016] The added amount of the catalyst is 0.5-0.6% of the total mass of diethylene glycol diacrylate or tetraethylene glycol diacrylate and (3-mercaptopropyl)trimethoxysilane.

[0017] Secondly, the present invention provides a method for preparing the above-mentioned silicon-modified acrylic pressure-sensitive adhesive, comprising the following steps:

[0018] Mix and stir the formulated amount of hard monomer, soft monomer and functional monomer to form a pre-emulsion;

[0019] A pre-emulsion with a formula volume of 10%, an initiator with a formula volume of 25-35% and a first solvent with a formula volume of 40-60% are placed in a reaction container, the temperature is raised to 70-90° C. and the reaction is stirred for 0.5-1h; then, a pre-emulsion with a formula volume of 90%, an initiator with a formula volume of 65-75% and the remaining first solvent are slowly added dropwise, and the reaction is continued to be stirred for 3-5h after the addition is completed; the temperature is lowered to below 40° C., a cross-linking curing agent is added, and the reaction is continued to be stirred for 0.3-1h to obtain a silicon-modified acrylic pressure-sensitive adhesive.

[0020] Thirdly, the present invention provides a pressure-sensitive adhesive tape, comprising an adhesive tape body and release film layers arranged on both sides of the adhesive tape body, characterized in that: the adhesive tape body comprises a first silicon-modified acrylic pressure-sensitive adhesive layer, a first primer layer, a butyl rubber elastomer layer, a second primer layer and a second silicon-modified acrylic pressure-sensitive adhesive layer arranged in sequence;

[0021] The first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer are both made of the silicon-modified acrylic pressure-sensitive adhesive or the silicon-modified acrylic pressure-sensitive adhesive prepared by the preparation method;

[0022] The thickness of the first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer are both 20 to 30 μm;

[0023] The thickness of the first primer layer and the second primer layer are both 0.5 to 5 μm;

[0024] The thickness of the butyl rubber elastomer layer is 30-40 μm.

[0025] Further, the first primer layer and the second primer layer are both made of a primer, and the primer includes the following raw material components in parts by weight: 80 to 100 parts of maleic anhydride grafted SEBS (SEBS-g-MAH), 10 to 30 parts of rosin resin, 10 to 20 parts of terpene phenol resin, 2 to 5 parts of silane coupling agent, and 150 to 200 parts of a second solvent;

[0026] The silane coupling agent is γ-piperazinepropylmethyldimethoxysilane;

[0027] The softening point of the rosin resin is 130-160°C;

[0028] The softening point of the terpene phenol resin is 80-100°C;

[0029] The grafting rate of the maleic anhydride grafted SEBS is 1.5-1.6%;

[0030] The second solvent is xylene or toluene.

[0031] Furthermore, the primer is prepared by the following method:

[0032] The maleic anhydride grafted SEBS, rosin resin and the second solvent are mixed, dissolved by a high-speed shear disperser, the terpene phenol resin is added, and high-speed shear dispersion is continued. Then, the silane coupling agent is added, and the mixture is evenly mixed by high-speed dispersion to obtain a primer.

[0033] Furthermore, the butyl rubber elastomer layer is selected from one of halogenated butyl rubber elastomer, sulfonated butyl rubber elastomer, maleic anhydride modified butyl rubber elastomer, and ternary butyl rubber elastomer, and the butyl rubber elastomer layer has a tensile strength of 15 to 25 MPa, an elongation of 400 to 700%, and a density of 0.6 to 0.9 g / cm 3 .

[0034] Fourthly, the present invention provides a method for preparing the above-mentioned pressure-sensitive adhesive tape, comprising the following steps:

[0035] (1) Applying a primer on both sides of the butyl rubber elastomer, drying it in an environment of 80 to 120° C. for 2 to 3 minutes, and leaving it at room temperature for 7 to 10 days or aging it in an environment of 60 to 80° C. for 24 to 48 hours to form a first primer layer and a second primer layer respectively;

[0036] (2) coating a silicon-modified acrylic pressure-sensitive adhesive on the first primer layer and the second primer layer, drying them at 80°C to 130°C for 2min to 3min to form a first silicon-modified acrylic pressure-sensitive adhesive layer and a second silicon-modified acrylic pressure-sensitive adhesive layer, respectively; arranging a release film on the outer sides of the first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer, and leaving them at room temperature for 7 to 10 days or aging them at 60 to 80°C for 24 to 48h to obtain an impact-resistant and buffer-type double-sided pressure-sensitive adhesive tape.

[0037] In the silicon-modified acrylic pressure-sensitive adhesive of the present invention, 2-(2-ethoxyethoxy)ethyl acrylate (EEA) contains ethylene glycol side chains, which are composed of hydrophilic (-CO-) and hydrophobic (-CC-) segments. Due to its high flexibility, polarity and chain length, a unique spiral or curled structure is formed. Due to the flexibility of the ethylene glycol chain, the chain entanglement of the EEA-based acrylic PSA increases, and a tightly packed structure is formed between the acrylic PSA chains. At the same time, due to the secondary bonding (hydrogen bonding formed by oxygen atoms) between the oxygen atoms in the ethylene glycol side chains, the interaction between the chains is strengthened, making the EEA-based acrylic PSA easy to entangle, thereby forming a higher gel fraction of the PSA and having excellent adhesion. Therefore, by introducing the chain entanglement improved by the ethylene glycol side chain and the physical crosslinking formed by the secondary bonding, the pressure-sensitive adhesive has good elasticity, can recover quickly during strain changes, and exhibits good recovery rate and recovery characteristics.

[0038] Silicon compounds have better mechanical and thermal properties than organic materials composed of carbon. In addition, the Si-O-Si bond angle is 140° to 180°, which is higher than the COC bond angle of 110°. Therefore, silicon compounds have high flexibility. The acrylic PSA of the present invention also introduces silane acrylate containing ethylene glycol chains as functional monomers, and introduces silane groups at the ends to compensate for the low cohesion and modulus at high temperatures of the acrylic PSA, so as to adjust its peel strength and rheological properties, and effectively improve the cohesion and adhesion properties of the acrylic PSA. Silane acrylate has a relatively high free volume due to the presence of ethylene glycol chains (-(CH2CH2O)-), silane fatty chains (-CH2-) and bulky terminal silane groups. The physical crosslinking of silane groups in silane acrylate improves cohesion. The ethylene glycol chains in silane acrylate are physically crosslinked through polymer entanglement. The silane groups are large in volume and have excellent heat resistance. These factors further improve the elasticity, heat resistance, and mechanical properties of acrylic PSA, and acrylic PSA can obtain stable viscoelastic behavior even at high temperatures.

[0039] The present invention uses a mixture of α-pinene methacrylate and methyl methacrylate (MMA) and / or methyl acrylate (MA) as a hard segment to increase the glass transition temperature of the adhesive, so that the adhesive can still maintain good viscosity at a higher temperature, thereby enhancing its heat resistance and chemical resistance. The presence of the hard segment enables the acrylic pressure-sensitive adhesive to maintain good stability and bonding effect when facing high temperature environments or chemical substances.

[0040] The adhesive tape of the present invention improves the bonding force between the glue and the substrate layer by coating the primer on the surface of the butyl rubber elastomer layer. The SEBS in the primer is a selective hydrogenation product of SBS. The butadiene part in the polymer main chain is hydrogenated and converted into an ethylene / butylene saturated elastomer, so that the main chain of the SEBS macromolecule does not contain unsaturated double bonds. Therefore, compared with SBS and SIS, SEBS has more stable properties in addition to excellent rubber elasticity, higher thermal stability and lower brittle temperature. However, since there are no polar groups and reactive functional groups on its molecular chain, according to the principle of like dissolves like, the compatibility between SEBS and polar polymers is poor. The present invention adopts maleic anhydride grafted SEBS (SEBS-g-MAH), and utilizes the unsaturated double bonds in the maleic anhydride molecules to improve the compatibility between non-polar polymers and polar polymers and improve the adhesion between different materials. The piperazine silane coupling agent added to the primer contains piperazine silane, which has two active amino groups that can promote adhesion and improve the softness and smoothness of the primer polymer. Rosin resin and terpene phenol resin are also used in the primer to improve adhesion.

[0041] The pressure-sensitive adhesive tape of the present invention comprises a first release film layer, a first silicon-modified acrylic pressure-sensitive adhesive layer, a first primer layer, a butyl rubber elastomer layer, a second primer layer, a second silicon-modified acrylic pressure-sensitive adhesive layer and a second release film layer; the release film layer is arranged on the outside of the silicone pressure-sensitive adhesive layer, and is used for release and peeling and also plays a protective role; the primer layer is directly coated on the butyl rubber elastomer layer, and the silicon-modified acrylic pressure-sensitive adhesive layer is adhered and superimposed on the butyl rubber elastomer layer by coating on the primer layer, and the primer layer has good adhesion to the butyl rubber elastomer layer and can serve as a connecting medium between the silicon-modified acrylic pressure-sensitive adhesive layer and the butyl rubber elastomer layer; the silicon-modified acrylic pressure-sensitive adhesive layer has excellent bonding strength, tensile strength and elasticity, and the butyl rubber elastomer layer has excellent damping performance, thereby ensuring an anti-impact buffering effect. DETAILED DESCRIPTION

[0042] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0043] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods, and the materials, reagents, etc. used are all available from commercial sources unless otherwise specified.

[0044] Example 1

[0045] (1) Preparation of primer:

[0046] Mix 100 parts by weight of SEBS-g-MAH (grafting rate 1.57%), 30 parts by weight of rosin resin and 150 parts by weight of xylene, dissolve them using a high-speed shear disperser, add 15 parts by weight of terpene phenol resin and 30 parts by weight of xylene, continue to disperse them using high-speed shear, then add 3 parts by weight of γ-piperazinepropylmethyldimethoxysilane, mix them evenly using a high-speed disperser, and prepare a primer for use.

[0047] (2) Preparation of silicone-modified acrylic pressure-sensitive adhesive

[0048] At room temperature, 10 parts by weight of diethylene glycol diacrylate was placed in a reaction container, and 9.2 parts by weight of (3-mercaptopropyl)trimethoxysilane was slowly added dropwise. After stirring and mixing evenly, 0.1 parts by weight of hexylamine catalyst was added. The reaction was stirred at room temperature for 4 hours, and purified by column chromatography to obtain silane-modified acrylate for later use.

[0049] Dissolve 1 part by weight of azobisisobutyronitrile in 20 parts by weight of ethyl acetate to form an initiator solution for later use;

[0050] 40 parts by weight of 2-(2-ethoxyethoxy)ethyl acrylate (EEA), 10 parts by weight of 2-hydroxyethyl acrylate (HEA), 10 parts by weight of decyl acrylate (OA), 10 parts by weight of butyl acrylate (BA), 10 parts by weight of 2-ethylhexyl acrylate (EHA), 2 parts by weight of α-pinene methacrylate, 13 parts by weight of methyl methacrylate (MMA) and 5 parts by weight of silane-modified acrylate were mixed and stirred to form a pre-emulsion;

[0051] 10 parts by weight of pre-emulsion, 6 parts by weight of initiator solution and 50 parts by weight of ethyl acetate are placed in a reaction container, heated to 80°C and stirred for reaction for 0.5h; then 90 parts by weight of pre-emulsion, 15 parts by weight of initiator solution and 30 parts by weight of ethyl acetate are slowly added dropwise, and after the addition is completed, the temperature is raised to 85°C, and the stirring reaction is continued for 5h, and the temperature is lowered to below 40°C, and 2 parts by weight of diphenylmethane diisocyanate are added, and the mixture is stirred and dispersed for 0.5h. The stirring speed is controlled at 800r / min during the whole process to obtain a silicon-modified acrylic pressure-sensitive adhesive.

[0052] (3) Preparation of impact-resistant and buffering double-sided pressure-sensitive tape

[0053] The butyl rubber elastomer layer is selected as a bromobutyl rubber elastomer with a thickness of 50 μm, a tensile strength of 20 MPa, an elongation of 500%, and a density of 0.81 g / cm 3 ;

[0054] A primer is applied on both sides of the butyl rubber elastomer, and the mixture is dried in an environment of 100° C. for 150 seconds, and then placed at room temperature for 8 days to form a first primer layer with a thickness of 2.5 μm and a second primer layer with a thickness of 2.5 μm, respectively; it should be noted that the thickness of the first primer layer and the second primer layer may be the same or different. In this embodiment, the thickness of the first primer layer and the second primer layer is the same. In other embodiments, the thickness of the first primer layer and the second primer layer may be different.

[0055] A silicon-modified acrylic pressure-sensitive adhesive is coated on the first primer layer and the second primer layer, and dried for 3 minutes in an environment of 120°C to form a first silicon-modified acrylic pressure-sensitive adhesive layer with a thickness of 30 μm and a second silicon-modified acrylic pressure-sensitive adhesive layer with a thickness of 30 μm, respectively, and a release film with a thickness of 100 μm is set on the outside of the first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer, and then aged for 48 hours in an environment of 60°C; an impact-resistant buffer double-sided pressure-sensitive adhesive tape is obtained. It should be noted that the thickness of the first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer may be the same or different. In this embodiment, the thickness of the first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer is the same. In other embodiments, the thickness of the first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer may be different.

[0056] The preparation methods of Example 2, Example 3 and Comparative Examples 1 to 4 are the same as that of Example 1, except for the raw material components and component contents. The specific raw material components and component contents are shown in Table 1.

[0057] Table 1

[0058]

[0059] The performance of the impact-resistant and buffering double-sided pressure-sensitive adhesive tapes prepared in Examples 1 to 3 and Comparative Examples 1 to 4 was tested. The test data are shown in Table 2.

[0060] Refer to standard GB / T 2792-2014 to test the 180° peel strength of pressure-sensitive tape at room temperature;

[0061] Refer to standard GB / T4851-2014 to test the adhesion of pressure-sensitive tape at room temperature;

[0062] Refer to standard GB / T4852-2002 to test the initial adhesion of pressure-sensitive tape at room temperature;

[0063] Refer to standard GB / T1040-2006 to test the elastic modulus of pressure-sensitive tape at room temperature;

[0064] Refer to standard GB / T6670-2008 to test the buffer rate of pressure-sensitive tape;

[0065] Aging test: In a test box with a temperature of 85℃±2℃ and a humidity of 85%RH±2%RH, perform appearance test after aging for 240h.

[0066] Table 2

[0067] Test items Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 thickness / 115 115 114 115 115 115 115 115 Rolling ball initial sticking (#) 20 19 20 18 16 14 19 18 Peel force (180°) / gf 3413 3230 3318 1890 1715 1627 2812 2303 Adhesion holding force 72H displacement (mm) 0 0 0 3 3 4 1 3 Elastic modulus GPa 1.4 1.3 1.3 0.9 1.0 0.8 1.2 1.1 Buffer rate (%) 59.3 50.2 59.8 43.7 40.4 42.6 46.6 47.9 Aging test No change No change No change Drum Drum No change No change Drum

[0068] According to the disclosure of the above description, those skilled in the art to which the present invention belongs may also make appropriate changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the scope of protection of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims

1. A silicon-modified acrylic pressure-sensitive adhesive, characterized in that: The raw materials include the following components: a hard monomer, a soft monomer, a functional monomer, an initiator, a first solvent and a curing cross-linking agent; The soft monomer accounts for 65-90% of the total mass of the monomers, the hard monomer accounts for 9-25% of the total mass of the monomers, the functional monomer accounts for 1-10% of the total mass of the monomers, the initiator is used in an amount of 0.5-2% of the total mass of the monomers, the curing cross-linking agent is used in an amount of 1-3% of the total mass of the monomers, and the ratio of the amount of the first solvent to the total mass of the monomers is 1:1; The soft monomer is a mixture of 2-(2-ethoxyethoxy)ethyl acrylate and 2-hydroxyethyl acrylate and at least one of decyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and 2-hydroxypropyl acrylate, wherein the 2-(2-ethoxyethoxy)ethyl acrylate accounts for 30-60% of the total mass of the soft monomer, and the 2-hydroxyethyl acrylate accounts for 8-15% of the total mass of the soft monomer; The hard monomer is a mixture of α-pinene methacrylate and methyl methacrylate and / or methyl acrylate, wherein the α-pinene methacrylate accounts for 10 to 20% of the total mass of the hard monomer; The functional monomer is silane-modified acrylate, and the silane-modified acrylate is prepared by the following method: At room temperature, diethylene glycol diacrylate or tetraethylene glycol diacrylate is placed in a reaction container, (3-mercaptopropyl)trimethoxysilane is slowly added dropwise, and after stirring and mixing, a catalyst is added, and the mixture is purified after reaction to obtain a silane-modified acrylate; The molar ratio of diethylene glycol diacrylate or tetraethylene glycol diacrylate to (3-mercaptopropyl)trimethoxysilane is 1:1; The added amount of the catalyst is 0.5-0.6% of the total mass of diethylene glycol diacrylate or tetraethylene glycol diacrylate and (3-mercaptopropyl)trimethoxysilane.

2. The silicon-modified acrylic pressure-sensitive adhesive according to claim 1, characterized in that: The initiator is at least one of benzoyl peroxide, azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate, tert-butyl benzoyl peroxide, and methyl ethyl ketone peroxide; The curing cross-linking agent is at least one of hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, tetramethyl meta-xylylene diisocyanate and toluene diisocyanate; The first solvent is ethyl acetate, xylene or toluene.

3. A method for preparing the silicon-modified acrylic pressure-sensitive adhesive according to claim 1, characterized in that: The steps include: Mix and stir the formulated amount of hard monomer, soft monomer and functional monomer to form a pre-emulsion; A pre-emulsion with a formula volume of 10%, an initiator with a formula volume of 25-35% and a first solvent with a formula volume of 40-60% are placed in a reaction container, the temperature is raised to 70-90° C. and the reaction is stirred for 0.5-1h; then, a pre-emulsion with a formula volume of 90%, an initiator with a formula volume of 65-75% and the remaining first solvent are slowly added dropwise, and the reaction is continued to be stirred for 3-5h after the addition is completed; the temperature is lowered to below 40° C., a cross-linking curing agent is added, and the reaction is continued to be stirred for 0.3-1h to obtain a silicon-modified acrylic pressure-sensitive adhesive.

4. A pressure-sensitive adhesive tape, comprising an adhesive tape body and release film layers disposed on both sides of the adhesive tape body, characterized in that: The tape body comprises a first silicon-modified acrylic pressure-sensitive adhesive layer, a first primer layer, a butyl rubber elastomer layer, a second primer layer and a second silicon-modified acrylic pressure-sensitive adhesive layer which are arranged in sequence; The first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer are both made of the silicon-modified acrylic pressure-sensitive adhesive according to claim 1 or the silicon-modified acrylic pressure-sensitive adhesive prepared by the preparation method according to claim 3; The first primer layer and the second primer layer are both made of a primer, and the primer includes the following raw material components in parts by weight: 80 to 100 parts of maleic anhydride grafted SEBS, 10 to 30 parts of rosin resin, 10 to 20 parts of terpene phenol resin, 2 to 5 parts of γ-piperazine propyl methyl dimethoxy silane, and 150 to 200 parts of a second solvent; The thickness of the first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer are both 20 to 30 μm; The thickness of the first primer layer and the second primer layer are both 0.5 to 5 μm; The thickness of the butyl rubber elastomer layer is 50 to 100 μm.

5. The pressure-sensitive adhesive tape according to claim 4, characterized in that: The softening point of the rosin resin is 130-160°C; The softening point of the terpene phenol resin is 80-100°C; The grafting rate of the maleic anhydride grafted SEBS is 1.5-1.6%; The second solvent is xylene or toluene.

6. The pressure-sensitive adhesive tape according to claim 4, characterized in that: The primer is prepared by the following method: The maleic anhydride grafted SEBS, rosin resin and the second solvent are mixed, dissolved by a high-speed shear disperser, the terpene phenol resin is added, and high-speed shear dispersion is continued. Then, the silane coupling agent is added, and the mixture is evenly mixed by high-speed dispersion to obtain a primer.

7. The pressure-sensitive adhesive tape according to claim 4, characterized in that: The butyl rubber elastomer layer is selected from one of halogenated butyl rubber elastomer, sulfonated butyl rubber elastomer, maleic anhydride modified butyl rubber elastomer and ternary butyl rubber elastomer. The butyl rubber elastomer layer has a tensile strength of 15-25 MPa, an elongation of 400-700%, and a density of 0.6-0.9 g / cm 3 .

8. A method for preparing a pressure-sensitive adhesive tape according to claim 4, characterized in that: The steps include: (1) applying a primer on both sides of the butyl rubber elastomer to form a first primer layer and a second primer layer, respectively; (2) coating a silicon-modified acrylic pressure-sensitive adhesive on the first primer layer and the second primer layer, and curing the coating to form a first silicon-modified acrylic pressure-sensitive adhesive layer and a second silicon-modified acrylic pressure-sensitive adhesive layer, respectively; (3) A release film is disposed on the outer sides of the first silicon-modified acrylic pressure-sensitive adhesive layer and the second silicon-modified acrylic pressure-sensitive adhesive layer to obtain a pressure-sensitive adhesive tape.

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