High-temperature-resistant high-peel-strength pressure-sensitive adhesive, aluminum foil tape and preparation method

Abstract

The invention discloses a high-temperature-resistant high-peel-strength pressure-sensitive adhesive, an aluminum foil adhesive tape and a preparation method. The preparation method of the high-temperature-resistant high-peel-strength pressure-sensitive adhesive comprises the following steps: preparing raw rubber from the following components in parts by weight: 5-15 parts of isopropanol, 200-220 parts of ethyl acetate, 120-140 parts of 2-ethylhexyl acrylate, 150-160 parts of n-butyl acrylate, 4-8 parts of hydroxyethyl acrylate, 10-15 parts of acrylic acid, 4-8 parts of beta-carboxyethyl acrylate and 0.5-1.5 parts of a peroxide initiator by adopting a method of solvent polymerization and step-by-step addition; the finished product glue comprises 90-110 parts of raw glue, 30-50 parts of tackifying resin, 10-30 parts of ethyl acetate and 0.5-1.0 part of a curing agent, the raw materials are weighed and uniformly stirred in a glue preparation kettle, the finished product glue is prepared, and the adhesive is good in high temperature resistance and also has excellent initial adhesion, peel strength and holding power. The aluminum foil adhesive tape prepared from the high-temperature-resistant high-peel-strength pressure-sensitive adhesive is high in tensile strength, strong in adhesive force, good in water resistance and corrosion resistance and good in high-temperature resistance, and can meet the application requirements of special occasions.

Description

Technical Field

[0001] The invention relates to the technical field of adhesive materials, and in particular to a high-temperature resistant and high-peel strength pressure-sensitive adhesive, an aluminum foil tape and a preparation method thereof. Background Art

[0002] Pressure-sensitive adhesive, commonly known as self-adhesive adhesive, is a semi-solid viscoelastic material used in a visco-fluid state. It only requires slight pressure to firmly adhere the pressure-sensitive adhesive to the surface of an object, and can be removed after use without leaving any residual adhesive. Pressure-sensitive adhesive tape is a product made by applying pressure-sensitive adhesive to a strip-shaped substrate. When the substrate is aluminum foil, it can be made into aluminum foil pressure-sensitive adhesive tape (hereinafter referred to as aluminum foil tape in the present invention). Aluminum foil tape is a metal foil tape with good viscosity, strong adhesion, and good anti-aging performance. It is widely used in the fixing and pasting of the side panel evaporator coils of refrigerators, freezers, etc., and has a good heat conduction effect.

[0003] When conventional aluminum foil tape products are used in high temperature environments, due to the low crosslinking density of the acrylic pressure-sensitive adhesive material in the tape, the molecular chains are prone to relative movement in high temperature environments, and the cohesive strength and adhesive properties are prone to decrease. The failure morphology after peeling is mainly cohesive failure, and there is a lot of residual adhesive, which cannot meet the application requirements. Without using special modified monomers and modifiers, the high temperature resistance of acrylic pressure-sensitive adhesive can be improved by adjusting factors such as the type and dosage of soft and hard monomers, molecular weight and crosslinking degree. The general rule is that the more hard monomers or functional monomers, the larger the product molecular weight, the greater the rigidity of the crosslinking agent, and the greater the crosslinking density, the better the temperature resistance of the obtained pressure-sensitive adhesive. However, it will also lead to a decrease in bonding strength and initial viscosity, thereby deteriorating the comprehensive performance of the pressure-sensitive adhesive. Therefore, it is necessary to explore a pressure-sensitive adhesive that is both resistant to high temperatures and has high peel strength, and use it in the preparation of aluminum foil tape to meet the application requirements of special occasions. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art, provide a high temperature resistant and high peel strength pressure sensitive adhesive, so that the obtained finished pressure sensitive adhesive has good comprehensive properties, and further make the pressure sensitive adhesive into an aluminum foil tape product.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows: A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of raw glue: accurately weigh the raw materials including 200-220 parts of ethyl acetate, 120-140 parts of isooctyl acrylate, 150-160 parts of n-butyl acrylate, 10-15 parts of acrylic acid, 4-8 parts of β-carboxyethyl acrylate, and 0.5-1.5 parts of peroxide initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to reflux temperature, and add 4-8 parts of hydroxyethyl acrylate and 5-15 parts of isopropanol within 2-3 hours after a small amount of steam is condensed and refluxed to the reactor from the condenser (the condensation water temperature is 20-23° C.), and keep the polymerization reaction system warm, continue the reaction for 3-4 hours, then stop heating, and wait for the reaction liquid to cool to below 50° C. to discharge the material, so as to obtain a solvent-based acrylic pressure-sensitive collagen glue; Furthermore, in the preparation of the original rubber, the reflux temperature is 86-90°C and the insulation temperature is 60-70°C.

[0006] Preparation of finished pressure-sensitive adhesive: Accurately weigh the raw materials including 90-110 parts of pressure-sensitive collagen glue, 30-50 parts of tackifying resin, 10-30 parts of ethyl acetate, and 0.5-1.0 parts of curing agent in a glue mixing kettle at room temperature and stir them evenly to obtain a finished pressure-sensitive adhesive.

[0007] Furthermore, in the preparation of the finished adhesive, the tackifying resin used is tackifying resin 138#.

[0008] Furthermore, in the preparation of the finished rubber, the stirring time is 5 to 8 h; Furthermore, the viscosity of the finished pressure-sensitive adhesive is measured at 23-25° C. to be 4000-6000 CPS (Centipoise, centipoise*second), and the solid content (ie, the content of non-volatile matter) is 58±1%.

[0009] Synthesis of aluminum foil tape: The solvent-based acrylic pressure-sensitive adhesive is coated on the aluminum foil substrate by a coating machine, and then baked in an oven to remove volatile organic compounds (mainly including isopropyl alcohol, ethyl acetate, etc.). Then, it is compounded with single-sided release paper to form a mother roll of tape, and finally cut into small rolls of tape of various specifications according to customer needs.

[0010] Furthermore, the baking temperature is 130-160° C., and the baking time is 2-5 min.

[0011] Furthermore, before the pressure-sensitive adhesive finished adhesive is coated on the aluminum foil substrate, the aluminum foil substrate is pretreated, and the pretreatment step includes: heating the aluminum foil substrate to 70-90°C and heating the finished adhesive to 50-70°C.

[0012] Furthermore, before the aluminum foil substrate and the pressure-sensitive adhesive are heated, the aluminum foil substrate is placed in an alkaline etching solution to remove a portion of the aluminum oxide film attached to the surface thereof.

[0013] Furthermore, the alkaline etching solution is at least one of a NaOH solution and a KOH solution with a concentration of 0.02-0.05 mol / L, and the alkaline etching solution is sprayed onto the surface where the aluminum foil and the finished adhesive are bonded using a spray gun at room temperature.

[0014] Furthermore, the ratio of the spraying amount of the alkaline etching solution to the area of ​​the aluminum foil is 50-100 mL / ㎡. The advantages and beneficial effects of the present invention are: 1. The present invention uses isooctyl acrylate, n-butyl acrylate, acrylic acid, and β-carboxyethyl acrylate as main raw materials, dibenzoyl peroxide as initiator, and ethyl acetate as solvent. A small amount of hydroxyethyl acrylate and isopropanol are added in the middle of the reaction process to polymerize in two stages, and the carboxylic acid (-COOH) groups of the main raw materials that have not been completely reacted are neutralized by esterification of hydroxyl groups (-OH), thereby synthesizing a solvent-based acrylic pressure-sensitive adhesive with excellent comprehensive properties.

[0015] 2. By controlling the reaction temperature, adjusting the dosage ratio between the soft monomer and the functional monomer in the adhesive, and adding functional monomers that can improve the adhesion and peel strength, the obtained high temperature resistant and high peel strength pressure-sensitive adhesive has a viscosity of 4000-6000 CPS, a solid content of 58±1%, good initial adhesion (≤10 cm), high peel strength (≥20N / 25mm), good sustained adhesion strength (≥24 h), and a wide temperature resistance range (-40~150℃), among which the peel strength (conventionally ≥15N / 25mm) and high temperature resistance (conventionally 120℃) are significantly improved.

[0016] 3. The present invention uses acrylic acid, hydroxyethyl acrylate and β-carboxyethyl acrylate as functional monomers, adjusts the -COOH content in the pressure-sensitive collagen adhesive by hydroxyethyl acrylate, and copolymerizes the added β-carboxyethyl acrylate with the acrylic monomer, so that the cross-linking points in the pressure-sensitive adhesive copolymer are increased, the cross-linking degree of the generated polymer chain is greater, and the cohesive strength of the pressure-sensitive adhesive is effectively improved, thereby improving the high temperature resistance of the aluminum foil tape. DETAILED DESCRIPTION

[0017] In the present invention, ethyl acetate is used as a solvent to help effectively disperse the monomers and control the activity of the monomers; Isooctyl acrylate and n-butyl acrylate are the main monomers, which play an adhesion role and improve the initial viscosity of the adhesive and the bonding performance of the interface.

[0018] Hydroxyethyl acrylate, acrylic acid and β-carboxyethyl acrylate are functional monomers that play a modifying role. Acrylic acid can improve the viscosity, strength and water resistance of the adhesive. β-carboxyethyl acrylate is easy to copolymerize with acrylic monomers due to its unique reactive acrylic double bond. It is also an adhesion promoter with good reactivity and adhesion. Its longer side carboxylic acid chain provides good flexibility (bending properties of the material), which enables effective interaction between the polymer and the substrate, thereby enhancing the adhesion and peel strength of the pressure-sensitive adhesive.

[0019] Benzoyl peroxide is an initiator that generates free radicals through decomposition, thereby initiating monomer polymerization.

[0020] Isopropyl alcohol is a molecular regulator that controls the molecular weight and molecular weight distribution of polymers by reacting with free radicals, slowing down the reaction rate while improving the reaction selectivity of hydroxyethyl acrylate in the polymerization reaction. Under the condition that isopropyl alcohol slows down the reaction rate of hydroxyethyl acrylate, the reactivity ratio of hydroxyethyl acrylate is reduced, so that at higher temperatures, the monomer is reduced from homopolymerization and copolymerized with other monomers or polymer segments, thereby improving the bonding strength and chemical resistance of the adhesive.

[0021] Isopropyl alcohol contains hydroxyl group (-OH). If it is directly added to the reactor at the beginning of the pressure-sensitive collagen reaction, an esterification reaction will occur. The esterification reaction formula is as follows: [RCOOH + CH3CHOHCH3→ RCOOCH(CH3)2 + H2O] In the formula: R is an acrylic monomer containing an alkane group and an alkene group.

[0022] Similarly, hydroxyethyl acrylate also contains hydroxyl groups, so it is added together with isopropyl alcohol in the later stage of the original glue preparation reaction to avoid imperfect or failure of its function due to esterification reaction. In addition, after the polymerization reaction reaches a certain stage (the reaction degree is about 0.3), the -OH in the added isopropyl alcohol and β-carboxyethyl acrylate will preferentially attack the -COOH existing in the side chain of the long polymer chain inside the acrylic pressure-sensitive adhesive, and combine with the incompletely fused acrylic monomers to control the pH value of the adhesive, avoid the automatic acceleration caused by excessive concentration of H· free radicals, ·OH free radicals and unreacted annihilated ·O2 free radicals, ensure the stable generation of the original glue, and promote the cross-linking reaction, so as to obtain a pressure-sensitive collagen base with a narrower molecular weight distribution, and then obtain a pressure-sensitive adhesive with more superior comprehensive performance.

[0023] Tackifying resin can provide adhesive with bonding force, wettability and reduce system viscosity; curing agent can promote the curing process of adhesive, making it gradually harden and stabilize over a certain period of time, and finally achieve high-strength bonding effect. Tackifying resin is water-based rosin resin, specifically a light-colored transparent solid formed by esterification of rosin with glycerol or pentaerythritol.

[0024] Before the aluminum foil substrate is coated with the pressure-sensitive adhesive finished adhesive, the aluminum foil substrate is pretreated, and the pretreatment step includes: before the aluminum foil substrate and the pressure-sensitive adhesive are heated, the aluminum foil substrate is placed in an alkaline solution with a concentration of 0.02~0.05mol / L, and the alkaline etching solution is sprayed on the surface where the aluminum foil and the finished adhesive are bonded at room temperature using a spray gun. On the one hand, it is to remove the aluminum oxide film on the surface of the aluminum foil substrate to prevent the aluminum oxide film from being too dense, resulting in poor bonding between the aluminum foil substrate body and the finished adhesive. The alkaline solution plays a role in corroding the aluminum oxide film layer. Too low or too high a concentration of the alkaline solution may lead to insufficient corrosion effect and damage to the aluminum foil. Spraying can be completed using a spray gun device. The ratio of the spraying amount of the alkaline etching solution to the area of ​​the aluminum foil is 50~100 mL / ㎡. The surface of the aluminum foil is sprayed until a large number of droplets with a diameter of about 0.5mm are visible to the naked eye, and they are evenly distributed. The distance between adjacent droplets is about 2mm.

[0025] In the process of compounding the aluminum foil substrate with the finished adhesive, the aluminum foil substrate and the finished adhesive are heated separately to soften the adhesive, enhance its fluidity, and more easily penetrate into the tiny bumps on the surface of the aluminum foil to form a closer contact, thereby improving the adhesion between the aluminum foil and the adhesive. Expel the air that may be generated during the compounding process, reduce the formation of bubbles, promote the uniform distribution of the adhesive, reduce defects in the composite material, and improve the quality of the finished product. Accelerate the compounding process, shorten the production cycle, improve production efficiency, and reduce the scrap rate caused by poor adhesion and reduce production costs. It should be noted that the heating temperature of the aluminum foil is higher than that of the finished adhesive. This is because the aluminum foil has excellent thermal conductivity. During the combination of the two, the heat dissipation of the aluminum foil is generally faster than that of the pressure-sensitive adhesive. In order to ensure that the temperature of the two is close when combined, when the aluminum foil cools and shrinks, it will not generate thermal stress at the interface with the finished adhesive and cause separation.

[0026] Optionally, the aluminum foil substrate is heated to 70-90°C and the finished adhesive is heated to 50-70°C after the alkali treatment. The etching effect of the alkali treatment can also be enhanced. In addition, a small amount of alkali will react with the aluminum oxide layer (Al2O3) on the surface of the aluminum foil to form soluble aluminates, thereby exposing more of the aluminum metal surface. Acrylic pressure-sensitive adhesives are usually made from acrylic ester monomers through polymerization reactions, and their molecular chains contain polar groups such as ester groups (-COO-). These polar groups may form coordination bonds or covalent bonds with the aluminum atoms exposed on the surface of the aluminum foil. The formation of these chemical bonds significantly enhances the bonding strength between the two compared to the general van der Waals force.

[0027] The specific implementation of the present invention is further described below in conjunction with the examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention, and cannot be used to limit the protection scope of the present invention.

[0028] Example 1 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of original glue: accurately weigh the raw materials including 210 parts of ethyl acetate, 130 parts of isooctyl acrylate, 155 parts of n-butyl acrylate, 12 parts of acrylic acid, 4 parts of β-carboxyethyl acrylate, and 1 part of ammonium persulfate initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 88° C. and reflux, add 4 parts of hydroxyethyl acrylate and 5 parts of isopropanol 2 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 3 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 100 parts of pressure-sensitive collagen glue, 35 parts of tackifying resin, 15 parts of ethyl acetate, and 0.7 parts of curing agent in a glue mixing kettle at room temperature for 5 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 4250 CPS, and the solid content was 58%.

[0029] Synthesis of aluminum foil tape: The solvent-based acrylic pressure-sensitive adhesive is coated on the aluminum foil substrate by a coating machine, baked in an oven at 145°C for 3 minutes, then compounded with single-sided release paper to form a mother roll tape, and finally cut into small rolls of tape of various specifications.

[0030] Example 2 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of original glue: accurately weigh the raw materials including: 220 parts of ethyl acetate, 140 parts of isooctyl acrylate, 150 parts of n-butyl acrylate, 10 parts of acrylic acid, 8 parts of β-carboxyethyl acrylate, and 1.2 parts of potassium persulfate initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 86° C. and reflux, add 8 parts of hydroxyethyl acrylate and 15 parts of isopropanol 2.5 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 4 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 110 parts of pressure-sensitive collagen glue, 50 parts of tackifying resin, 10 parts of ethyl acetate, and 1 part of curing agent in a glue mixing kettle at room temperature for 6 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 5850 CPS, and the solid content was 57%.

[0031] Synthesis of aluminum foil tape: The solvent-based acrylic pressure-sensitive adhesive is coated on the aluminum foil substrate by a coating machine, baked in an oven at 130°C for 5 minutes, then compounded with single-sided release paper to form a mother roll of tape, and finally cut into small rolls of tape of various specifications.

[0032] Example 3 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of raw glue: accurately weigh the raw materials including 200 parts of ethyl acetate, 131 parts of isooctyl acrylate, 152 parts of n-butyl acrylate, 15 parts of acrylic acid, 7 parts of β-carboxyethyl acrylate, and 0.5 parts of benzoyl peroxide initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 90° C. and reflux, add 8 parts of hydroxyethyl acrylate and 15 parts of isopropanol 3 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 4 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 105 parts of pressure-sensitive collagen glue, 50 parts of tackifying resin, 10 parts of ethyl acetate, and 1 part of curing agent in a glue mixing kettle at room temperature for 6 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 5550 CPS, and the solid content was 59%.

[0033] Synthesis of aluminum foil tape: The solvent-based acrylic pressure-sensitive adhesive is coated on the aluminum foil substrate by a coating machine, baked in an oven at 160°C for 2 minutes, then compounded with single-sided release paper to form a mother roll of tape, and finally cut into small rolls of tape of various specifications.

[0034] Example 4 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of original glue: accurately weigh the raw materials including: 220 parts of ethyl acetate, 140 parts of isooctyl acrylate, 155 parts of n-butyl acrylate, 10 parts of acrylic acid, 8 parts of β-carboxyethyl acrylate, and 1 part of ammonium persulfate initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 86° C. and reflux, add 6 parts of hydroxyethyl acrylate and 5 parts of isopropanol 3 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 4 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 90 parts of pressure-sensitive collagen glue, 50 parts of tackifying resin, 10 parts of ethyl acetate, and 1 part of curing agent in a glue mixing kettle at room temperature for 5 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 6000 CPS, and the solid content was 58%.

[0035] Synthesis of aluminum foil tape: pre-treat the aluminum foil substrate, heat the aluminum foil substrate to 70°C, and heat the finished adhesive to 50°C. Then, coat the solvent-based acrylic pressure-sensitive adhesive finished adhesive on the aluminum foil substrate through a coating machine, bake it in an oven at 140°C for 4 minutes, and then compound the single-sided release paper to form a mother roll tape, and finally cut it into small rolls of tape of various specifications.

[0036] Example 5 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of original glue: accurately weigh the raw materials including: 220 parts of ethyl acetate, 140 parts of isooctyl acrylate, 160 parts of n-butyl acrylate, 15 parts of acrylic acid, 8 parts of β-carboxyethyl acrylate, and 1.5 parts of potassium persulfate initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 90° C. and reflux, add 8 parts of hydroxyethyl acrylate and 15 parts of isopropanol 2.5 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 4 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 110 parts of pressure-sensitive collagen glue, 50 parts of tackifying resin, 10 parts of ethyl acetate, and 1 part of curing agent in a glue preparation kettle at room temperature for 5 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 5600 CPS, and the solid content was 58%.

[0037] Synthesis of aluminum foil tape: pre-treat the aluminum foil substrate, heat the aluminum foil substrate to 80°C, and heat the finished adhesive to 70°C. Then, coat the solvent-based acrylic pressure-sensitive adhesive finished adhesive on the aluminum foil substrate through a coating machine, bake it in an oven at 150°C for 3 minutes, and then compound the single-sided release paper to form a mother roll tape, and finally cut it into small rolls of tape of various specifications.

[0038] Example 6 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of original glue: accurately weigh the raw materials including 220 parts of ethyl acetate, 140 parts of isooctyl acrylate, 160 parts of n-butyl acrylate, 15 parts of acrylic acid, 8 parts of β-carboxyethyl acrylate, and 1.5 parts of ammonium persulfate initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 90° C. and reflux, add 8 parts of hydroxyethyl acrylate and 15 parts of isopropanol 2.5 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 4 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 110 parts of pressure-sensitive collagen glue, 50 parts of tackifying resin, 10 parts of ethyl acetate, and 1 part of curing agent in a glue preparation kettle at room temperature for 5 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 5600 CPS, and the solid content was 58%.

[0039] Synthesis of aluminum foil tape: pre-treat the aluminum foil substrate, heat the aluminum foil substrate to 90°C, and heat the finished adhesive to 60°C. Then, coat the solvent-based acrylic pressure-sensitive adhesive finished adhesive on the aluminum foil substrate through a coating machine, bake it in an oven at 160°C for 2 minutes, and then compound the single-sided release paper to form a mother roll tape, and finally cut it into small rolls of tape of various specifications.

[0040] Example 7 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of original glue: accurately weigh the raw materials including 210 parts of ethyl acetate, 130 parts of isooctyl acrylate, 150 parts of n-butyl acrylate, 15 parts of acrylic acid, 8 parts of β-carboxyethyl acrylate, and 1.5 parts of potassium persulfate initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 92° C. and reflux, add 8 parts of hydroxyethyl acrylate and 15 parts of isopropanol 2.5 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 4 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 105 parts of pressure-sensitive collagen glue, 45 parts of tackifying resin, 45 parts of ethyl acetate, and 0.5 parts of curing agent in a glue mixing kettle at room temperature for 5 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 6000 CPS, and the solid content was 59%.

[0041] Synthesis of aluminum foil tape: pre-treat the aluminum foil substrate, place the aluminum foil substrate in 0.02mol / L NaOH solution, and use a spray gun to spray alkaline etching solution on the surface where the aluminum foil and the finished adhesive are combined at room temperature. The ratio of the amount of etching solution sprayed to the area of ​​the aluminum foil is 50 mL / ㎡. Heat the aluminum foil substrate to 70℃ and the finished adhesive to 50℃. Then, the solvent-based acrylic pressure-sensitive adhesive finished adhesive is coated on the aluminum foil substrate by a coating machine, and baked in an oven at 130℃ for 4 minutes. Then, the single-sided release paper is compounded to form a mother roll tape, and finally cut into small rolls of tape of various specifications.

[0042] Example 8 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of original glue: accurately weigh the raw materials including: 210 parts of ethyl acetate, 120 parts of isooctyl acrylate, 150 parts of n-butyl acrylate, 12 parts of acrylic acid, 4 parts of β-carboxyethyl acrylate, and 1 part of potassium persulfate initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 86° C. and reflux, add 6 parts of hydroxyethyl acrylate and 8 parts of isopropanol 2 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 4 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 100 parts of pressure-sensitive collagen glue, 50 parts of tackifying resin, 30 parts of ethyl acetate, and 0.5 parts of curing agent in a glue mixing kettle at room temperature for 5 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 4000 CPS, and the solid content was 57%.

[0043] Synthesis of aluminum foil tape: pre-treat the aluminum foil substrate, place the aluminum foil substrate in 0.05mol / L NaOH solution, and use a spray gun to spray alkaline etching solution on the surface where the aluminum foil and the finished adhesive are combined at room temperature. The ratio of the amount of etching solution sprayed to the area of ​​the aluminum foil is 100 mL / ㎡. Heat the aluminum foil substrate to 70℃ and the finished adhesive to 50℃. Then, apply the solvent-based acrylic pressure-sensitive adhesive finished adhesive to the aluminum foil substrate through a coating machine, bake it in an oven at 130℃ for 4 minutes, and then compound the single-sided release paper to make a mother roll tape, and finally cut it into small rolls of tape of various specifications.

[0044] Example 9 A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive comprises the following steps: Preparation of original glue: accurately weigh the raw materials including: 210 parts of ethyl acetate, 120 parts of isooctyl acrylate, 160 parts of n-butyl acrylate, 10 parts of acrylic acid, 8 parts of β-carboxyethyl acrylate, and 1.5 parts of ammonium persulfate initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to 92° C. and reflux, add 8 parts of hydroxyethyl acrylate and 15 parts of isopropanol 3 hours after a small amount of steam is condensed and refluxed to the reactor, continue to react for 4 hours, then stop heating, wait for the reaction liquid to cool to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of pressure-sensitive adhesive finished product: accurately weigh the raw materials including: 100 parts of pressure-sensitive collagen glue, 35 parts of tackifying resin, 15 parts of ethyl acetate, and 1 part of curing agent in a glue preparation kettle at room temperature for 5 hours to obtain a pressure-sensitive adhesive finished product. The viscosity of the pressure-sensitive adhesive finished product was measured to be 4250 CPS, and the solid content was 58%.

[0045] Synthesis of aluminum foil tape: pre-treat the aluminum foil substrate, place the aluminum foil substrate in a 0.05 mol / L NaOH:KOH=1:1 solution, and use a spray gun to spray the alkaline etching solution on the surface where the aluminum foil and the finished adhesive are combined at room temperature. The ratio of the amount of etching solution sprayed to the area of ​​the aluminum foil is 75 mL / ㎡. Heat the aluminum foil substrate to 70℃ and the finished adhesive to 50℃. Then, apply the solvent-based acrylic pressure-sensitive adhesive finished adhesive to the aluminum foil substrate through a coating machine, bake it in an oven at 130℃ for 4 minutes, and then compound the single-sided release paper to make a mother roll tape, and finally cut it into small rolls of tape of various specifications.

[0046] Comparative Example 1 An aluminum foil tape is different from Example 1 only in that: the solvent-based acrylate pressure-sensitive adhesive prepared by adding β-carboxyethyl acrylate is not added, and the remaining components and preparation steps are the same as those in Example 1.

[0047] Comparative Example 2 An aluminum foil tape, which is different from Example 4 only in that the aluminum foil substrate is not pre-treated by heating.

[0048] Comparative Example 3 An aluminum foil tape, which is different from Example 7 only in that the aluminum foil substrate is not subjected to alkali treatment.

[0049] The performance test results of the composite sheets prepared in the embodiments and comparative examples are shown in the following table: Test items Initial viscosity (cm) 180° peel strength (N / 15mm) Adhesion strength at room temperature (h) Temperature range (℃) Test Standards GB / T4852-2002 GB / T2792-2014 GB / T4851-2002 GB / T32368-2015 Example 1 ≤12 ≥20 ≥24 -40~125 Example 2 ≤10 ≥20 ≥24 -40~125 Example 3 ≤11 ≥20 ≥24 -40~125 Example 4 ≤11 ≥25 ≥36 -40~130 Example 5 ≤10 ≥24 ≥36 -40~135 Example 6 ≤10 ≥22 ≥36 -40~135 Example 7 ≤11 ≥25 ≥48 -40~140 Example 8 ≤10 ≥23 ≥48 -40~140 Example 9 ≤10 ≥24 ≥48 -40~150 Comparative Example 1 ≤10 ≥20 ≥24 -40~120 Comparative Example 2 ≤10 ≥20 ≥24 -40~120 Comparative Example 3 ≤10 ≥20 ≥24 -40~120 The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A high temperature resistant and high peel strength pressure sensitive adhesive, characterized in that: The invention comprises the following components in parts by weight: 200-220 parts of ethyl acetate, 120-140 parts of isooctyl acrylate, 150-160 parts of n-butyl acrylate, 10-15 parts of acrylic acid, 4-8 parts of beta-carboxyethyl acrylate, 0.5-1.5 parts of peroxide initiator, 4-8 parts of hydroxyethyl acrylate and 5-15 parts of isopropanol.

2. A method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive according to claim 1, characterized in that: The following steps are involved: Preparation of raw glue: accurately weigh the raw materials including 200-220 parts of ethyl acetate, 120-140 parts of isooctyl acrylate, 150-160 parts of n-butyl acrylate, 10-15 parts of acrylic acid, 4-8 parts of β-carboxyethyl acrylate, and 0.5-1.5 parts of peroxide initiator, put them into a reactor and stir them evenly, then gradually heat the reactor to reflux temperature, add 4-8 parts of hydroxyethyl acrylate and 5-15 parts of isopropanol within 2-3 hours after a small amount of steam is condensed and refluxed into the reactor, keep the polymerization reaction system warm, and after the reaction is completed, cool the reaction liquid to below 50° C. and discharge the material to obtain a solvent-based acrylic pressure-sensitive collagen glue; Preparation of finished pressure-sensitive adhesive: accurately weigh the raw materials including 90-110 parts of pressure-sensitive collagen glue, 30-50 parts of tackifying resin, 10-30 parts of ethyl acetate, and 0.5-1.0 parts of curing agent in a glue mixing kettle at room temperature and mix them evenly to obtain a finished pressure-sensitive adhesive.

3. The method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive according to claim 2, characterized in that: During the preparation of the raw rubber, the reflux temperature is 86-90° C.; the insulation temperature is 60-70° C.; and after adding hydroxyethyl acrylate and isopropanol, the reaction is continued for 3-4 hours.

4. The method for preparing a high temperature resistant and high peel strength pressure sensitive adhesive according to claim 2, characterized in that: During the preparation of the finished adhesive, the stirring time is 5 to 8 hours; the viscosity of the solvent-based acrylic pressure-sensitive adhesive finished adhesive is 4000 to 6000 CPS, and the solid content is 58±1%.

5. An aluminum foil tape made of the pressure-sensitive adhesive according to claim 2, characterized in that: The preparation method includes: coating the finished pressure-sensitive adhesive on an aluminum foil substrate through a coating machine, baking it in an oven, then compounding the baked aluminum foil substrate and the pressure-sensitive adhesive with a single-sided release paper to form a mother roll tape, and finally slitting the mother roll tape into small rolls of tape of various specifications.

6. The method for preparing the aluminum foil tape according to claim 5, characterized in that: The baking temperature is 130~160℃; the baking time is 2~5 min.

7. The method for preparing the aluminum foil tape according to claim 5, characterized in that: Before coating the pressure-sensitive adhesive finished adhesive on the aluminum foil substrate, the aluminum foil substrate is pretreated, and the pretreatment step includes: heating the aluminum foil substrate to 70-90° C. and heating the finished adhesive to 50-70° C.

8. The method for preparing the aluminum foil tape according to claim 5, characterized in that: Before coating the aluminum foil substrate with the finished pressure-sensitive adhesive, the aluminum foil substrate is pretreated, and the pretreatment step includes: placing the aluminum foil substrate in an alkaline etching solution to remove part of the aluminum oxide film attached to the surface thereof.

9. The method for preparing the aluminum foil tape according to claim 8, characterized in that: The alkaline etching solution has a concentration of 0.02-0.05 mol / L, and is sprayed onto the surface where the aluminum foil and the finished adhesive are bonded at room temperature.

10. The method for preparing the aluminum foil tape according to claim 8, characterized in that: The ratio of the spraying amount of the alkaline etching solution to the area of ​​the aluminum foil is 50-100 mL / ㎡.