Low-temperature-resistant aluminum foil adhesive tape and preparation method thereof

Abstract

The application discloses a low-temperature-resistant aluminum foil adhesive tape and a preparation method thereof, and relates to the technical field of adhesives. The application adopts a soft and hard monomer staged polymerization process to prepare a pressure-sensitive adhesive layer. In the early stage, soft monomers such as isooctyl acrylate are put in to form a continuous phase with a low glass transition temperature. In the later stage, hard monomers such as methyl methacrylate and acrylonitrile are added to form side chain distribution on the main chain and separate into dispersed rigid regions after film formation. The flexible phase maintains the molecular chain movement ability at low temperature, ensuring the wetting and initial adhesion to the pasted surface. The rigid region limits the slip of the adhesive layer and prevents falling by acting as a physical connection node. The scheme can balance the low-temperature initial adhesion and cohesive strength by using only a tackifying resin with a low softening point and a trace amount of metal crosslinking agent, thereby avoiding low-temperature embrittlement. The initial adhesion, peeling and holding adhesion performance of the obtained product at low temperature all meet the sealing requirements, and the process adaptability is good, and the raw material cost is controllable.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, specifically to a low-temperature resistant aluminum foil tape and its preparation method. Background Technology

[0002] When used in low-temperature environments, the initial tack performance of existing aluminum foil tapes generally declines. The main reason for this is that the polymer molecular chains in conventional pressure-sensitive adhesives exhibit reduced thermal mobility at low temperatures, with chain segments in a frozen or semi-frozen state. This prevents them from responding to external pressure and deforming quickly enough, resulting in ineffective intermolecular contact between the adhesive layer and the surface of the substrate. Consequently, the tape is prone to peeling, displacement, or even complete detachment after application. This problem is particularly pronounced in winter outdoor construction, cold chain logistics, and building maintenance in northern regions, severely impacting the reliability and lifespan of the aluminum foil tape.

[0003] To address the issue of low-temperature tack loss, the industry typically employs the following approaches. The first approach is to increase the proportion of soft monomers such as isooctyl acrylate in the acrylate copolymer, thereby lowering the glass transition temperature of the adhesive layer to maintain the flexibility and mobility of the molecular chains at low temperatures. The drawback of this method is that an excessively high proportion of soft monomers significantly reduces the cohesive strength of the polymer, causing creep deformation of the adhesive layer under sustained shear stress, leading to tape slippage or detachment, and insufficient tack to meet long-term sealing or fixing requirements. The second approach is to add high-softening-point tackifying resins, attempting to improve peel strength through the adhesive contribution of the tackifying resin. However, high-softening-point tackifying resins are inherently brittle at low temperatures, with relatively rigid molecular chain segments. Introducing large quantities not only fails to improve low-temperature initial tack performance but also makes the adhesive layer harder and more brittle, further reducing the adhesion between the adhesive layer and the surface of the substrate, exacerbating the low-temperature tack loss problem. The third approach is to increase the amount of crosslinking agent, enhancing the cohesive strength by increasing the crosslinking density of the adhesive layer to compensate for insufficient tack caused by an excessively high proportion of soft monomers. However, excessively high crosslinking density restricts the free movement of polymer molecular chains, especially in low-temperature environments. This restriction is more pronounced, resulting in excessive stiffness and insufficient adhesion of the adhesive layer, making it difficult to form a tight bond with the surface of the object being bonded. Initial tack and peel strength both decrease simultaneously.

[0004] It can be seen that there is a clear interdependence among low-temperature resistance, peel strength, and holding power in existing technologies. Simply increasing the proportion of soft monomers improves initial tack at low temperatures but sacrifices holding power. Similarly, simply adding high-softening-point tackifying resins or increasing the amount of crosslinking agents improves peel strength or holding power but exacerbates low-temperature embrittlement. Conventional formulation adjustments are insufficient to simultaneously meet the performance requirements of all three aspects. Therefore, new technological pathways need to be explored in adhesive molecular structure design and polymerization processes to ensure that the adhesive layer maintains sufficient molecular chain mobility at low temperatures to achieve good initial tack while also possessing sufficient cohesive strength to resist peel and shear stresses, thereby addressing the problem of insufficient low-temperature resistance in existing aluminum foil tapes. Summary of the Invention

[0005] The purpose of this invention is to provide a low-temperature resistant aluminum foil tape and its preparation method to solve the problems existing in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a low-temperature resistant aluminum foil tape, wherein the pressure-sensitive adhesive is composed of an acrylic copolymer base adhesive, a tackifying resin and a crosslinking agent; Acrylic copolymer-based adhesives are prepared through a staged polymerization process, and the raw material composition, by mass percentage, includes: 35-40 parts of isooctyl acrylate 10-15 parts butyl acrylate 8-12 parts of methyl methacrylate 3-6 parts acrylonitrile 1-2 parts acrylic acid Hydroxyethyl acrylate 0.5-1.5 parts 15-20 parts of toluene 20-25 parts of ethyl acetate 0.3-0.6 parts of benzoyl peroxide.

[0007] Furthermore, the tackifying resin is selected from rosin-modified resin with a softening point of 90-95℃, and its addition amount is 12-18% relative to the solid content of the acrylate copolymer base.

[0008] Furthermore, the crosslinking agent is aluminum acetylacetonate, and the amount added is 0.1-0.3% relative to the solid content of the acrylate copolymer base.

[0009] Furthermore, a method for preparing a low-temperature resistant aluminum foil tape includes the following preparation steps: (1) Add 70% of the total amount of toluene and ethyl acetate to the reactor as the initial solvent, and then add 40% of the total amount of isooctyl acrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and benzoyl peroxide; purge the reactor with inert gas for 20 min, and stir under slight positive pressure; slowly raise the temperature and react under reflux for 2 h; (2) Mix methyl methacrylate, acrylonitrile, and the remaining 30% of toluene and ethyl acetate evenly, and then add 30% of the total amount of benzoyl peroxide to prepare a hard monomer mixture. Add the mixture dropwise to the reactor at a uniform flow rate over 2 hours, maintain the reaction temperature and continue reflux, and keep the stirring speed constant. After the dropwise addition is complete, add the remaining 30% of benzoyl peroxide and continue to keep the temperature for 3 hours. Then, cool the reactor and keep it at a constant temperature for 4 hours to ensure that the polymerization reaction is complete. Finally, cool to room temperature and discharge the material to obtain the acrylate copolymer base rubber. (3) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 12-18 parts of rosin-modified tackifying resin, add 0.1-0.3 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s, stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (4) Select aluminum foil substrate with no base coating treatment; apply pressure-sensitive adhesive evenly to the glossy surface of the aluminum foil using a scraper coating method, with a dry adhesive thickness of 40-50μm; after coating, the aluminum foil enters the drying oven, which is divided into three temperature zones: the first temperature zone is 3m long and the temperature is 85℃, the second temperature zone is 3m long and the temperature is 100℃, and the third temperature zone is 4m long and the temperature is 115℃, with a total drying time of 3min; after exiting the drying oven, the foil is wound up by a winding device with a winding tension set to 8N; (5) Place the rolled aluminum foil tape at 23°C for 48 hours to allow the cross-linking reaction in the adhesive layer to proceed fully before slitting and packaging.

[0010] Furthermore, the inert gas in step (1) is nitrogen.

[0011] Furthermore, the stirring speed in step (1) is 150 rpm.

[0012] Furthermore, in step (1), the temperature is raised to 95°C.

[0013] Furthermore, in step (2), the temperature is reduced to 85°C.

[0014] Furthermore, in step (4), the thickness of the aluminum foil substrate is 0.05 mm.

[0015] Furthermore, the coating speed in step (4) is 5-9 m / min.

[0016] Compared with the prior art, the beneficial effects achieved by the present invention are: This invention provides a low-temperature resistant aluminum foil tape, the pressure-sensitive adhesive layer of which is prepared by a staged polymerization process of soft and hard monomers.

[0017] This invention introduces soft monomers such as isooctyl acrylate in the early stage of polymerization to form a molecular backbone with a low glass transition temperature. In the later stage of polymerization, hard monomers such as methyl methacrylate and acrylonitrile are added, causing them to form side chains on the backbone. After the copolymer is dried and formed into a film, the hard monomer segments, due to their low compatibility with the soft monomer segments, spontaneously separate into dispersed rigid regions within the adhesive layer, while the soft monomer segments form a continuous flexible phase. Based on this structure, the flexible phase can maintain molecular chain mobility at low temperatures, effectively wetting the surface of the adhered object and providing stable initial adhesion. The rigid regions, acting as physical bonding nodes, limit the overall slippage of the adhesive layer under peel or shear stress, preventing premature detachment. Unlike conventional formulations that increase cohesive strength by adding large amounts of high softening-point tackifying resins or high crosslinking densities, this method only requires a low softening-point tackifying resin and a trace amount of metal crosslinking agent to achieve sufficient cohesive strength while maintaining low-temperature initial tack, avoiding low-temperature embrittlement of the adhesive layer caused by excessive tackifying resin or crosslinking agent. The aluminum foil tape prepared using the above technical solution can meet the sealing construction requirements in terms of initial tack and peel strength under low temperature conditions, and the holding time is also extended compared with existing products.

[0018] The preparation process is well compatible with existing coating equipment, the raw material cost is controllable, and the content of volatile organic compounds is low, making it suitable for mass production. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] To more clearly illustrate the method provided by the present invention, the following embodiments are provided in detail. The testing methods for various indicators of a low-temperature resistant aluminum foil tape produced in the following embodiments are as follows: Adhesion performance test: Based on GB / T 2791 as the reference standard, the peel strength of the samples from the examples and comparative examples was determined using an electronic universal tensile testing machine at a test temperature of 25℃. Low temperature resistance test: Take the samples from the examples and comparative examples, place them at -10℃, and test their peel strength again; Mechanical property testing: The samples of the examples and comparative examples were placed in polytetrafluoroethylene molds and dried at room temperature for 7 days. The tensile properties of the samples were tested using an electronic universal tensile testing machine. The samples were dumbbell strips of 25 mm × 4 mm and the tensile rate was 500 mm / min. Example 1

[0021] The pressure-sensitive adhesive is composed of an acrylate copolymer base adhesive, a tackifying resin, and a crosslinking agent. The acrylate copolymer base adhesive is prepared through a staged polymerization process. The raw material composition, by mass percentage, includes: 35 parts isooctyl acrylate, 10 parts butyl acrylate, 8 parts methyl methacrylate, 3 parts acrylonitrile, 1 part acrylic acid, 0.5 parts hydroxyethyl acrylate, 15 parts toluene, 20 parts ethyl acetate, and 0.3 parts benzoyl peroxide. The tackifying resin is a rosin-modified resin with a softening point of 90℃, added at 12% of the acrylate copolymer base adhesive's solid content. The crosslinking agent is aluminum acetylacetonate, added at 0.1% of the acrylate copolymer base adhesive's solid content. (1) Synthesis of acrylate copolymer base adhesive; 70% of the total amount of toluene and ethyl acetate was added to the reaction vessel as the initial solvent, and then 40% of the total amount of isooctyl acrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and benzoyl peroxide was added; nitrogen was introduced to replace the air in the vessel for 20 min, maintaining a slight positive pressure, stirring was started and the stirring speed was set to 150 rpm; the temperature was slowly raised to 95℃ and reacted under reflux for 2 h; (2) Mix methyl methacrylate, acrylonitrile, and the remaining 30% of toluene and ethyl acetate evenly, and then add 30% of the total amount of benzoyl peroxide to prepare a hard monomer mixture. Add the mixture dropwise to the reactor at a uniform flow rate over 2 hours, maintain the reaction temperature at 95°C and continue reflux, and keep the stirring speed constant. After the dropwise addition is complete, add the remaining 30% of benzoyl peroxide and continue to keep the temperature for 3 hours. Then lower the temperature of the reactor to 85°C and keep it at a constant temperature for 4 hours to ensure that the polymerization reaction is complete. Finally, cool to room temperature and discharge the material to obtain the acrylate copolymer base rubber. (3) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 12 parts of rosin-modified tackifying resin, add 0.1 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s. Stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (4) Select aluminum foil substrate with a thickness of 0.05 mm, the surface of which has not been pre-coated; apply pressure-sensitive adhesive evenly to the bright surface of the aluminum foil by scraping, the dry adhesive thickness is 40 μm, the coating speed is 5 m / min; after coating, the aluminum foil enters the drying oven, which is divided into three temperature zones: the first temperature zone is 3 m long and the temperature is 85℃, the second temperature zone is 3 m long and the temperature is 100℃, and the third temperature zone is 4 m long and the temperature is 115℃, the total drying time is 3 min; after exiting the drying oven, it is wound up by a winding device, and the winding tension is set to 8 N; (5) Place the rolled aluminum foil tape at 23°C for 48 hours to allow the cross-linking reaction in the adhesive layer to proceed fully before slitting and packaging. Example 2

[0022] The pressure-sensitive adhesive is composed of an acrylate copolymer base adhesive, a tackifying resin, and a crosslinking agent. The acrylate copolymer base adhesive is prepared through a staged polymerization process. The raw material composition, by mass percentage, includes: 36.25 parts isooctyl acrylate, 11.25 parts butyl acrylate, 9 parts methyl methacrylate, 3.75 parts acrylonitrile, 1.25 parts acrylic acid, 0.75 parts hydroxyethyl acrylate, 16.25 parts toluene, 21.25 parts ethyl acetate, and 0.38 parts benzoyl peroxide. The tackifying resin is a rosin-modified resin with a softening point of 91.25℃, added at 13.5% of the acrylate copolymer base adhesive's solid content. The crosslinking agent is aluminum acetylacetonate, added at 0.15% of the acrylate copolymer base adhesive's solid content. (1) Synthesis of acrylate copolymer base adhesive; 70% of the total amount of toluene and ethyl acetate was added to the reaction vessel as the initial solvent, and then 40% of the total amount of isooctyl acrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and benzoyl peroxide was added; nitrogen was introduced to replace the air in the vessel for 20 min, maintaining a slight positive pressure, stirring was started and the stirring speed was set to 150 rpm; the temperature was slowly raised to 95℃ and reacted under reflux for 2 h; (2) Mix methyl methacrylate, acrylonitrile, and the remaining 30% of toluene and ethyl acetate evenly, and then add 30% of the total amount of benzoyl peroxide to prepare a hard monomer mixture. Add the mixture dropwise to the reactor at a uniform flow rate over 2 hours, maintain the reaction temperature at 95°C and continue reflux, and keep the stirring speed constant. After the dropwise addition is complete, add the remaining 30% of benzoyl peroxide and continue to keep the temperature for 3 hours. Then lower the temperature of the reactor to 85°C and keep it at a constant temperature for 4 hours to ensure that the polymerization reaction is complete. Finally, cool to room temperature and discharge the material to obtain the acrylate copolymer base rubber. (3) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 13.5 parts of rosin-modified tackifying resin, add 0.15 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s. Stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (4) Select aluminum foil substrate with a thickness of 0.05 mm, the surface of which has not been pre-coated; apply pressure-sensitive adhesive evenly to the bright surface of the aluminum foil by scraping, the dry adhesive thickness is 42.5 μm, the coating speed is 6 m / min; after coating, the aluminum foil enters the drying oven, which is divided into three temperature zones: the first temperature zone is 3 m long and the temperature is 85℃, the second temperature zone is 3 m long and the temperature is 100℃, and the third temperature zone is 4 m long and the temperature is 115℃, the total drying time is 3 min; after exiting the drying oven, it is wound up by a winding device, the winding tension is set to 8 N; (5) Place the rolled aluminum foil tape at 23°C for 48 hours to allow the cross-linking reaction in the adhesive layer to proceed fully before slitting and packaging. Example 3

[0023] The pressure-sensitive adhesive is composed of an acrylate copolymer base adhesive, a tackifying resin, and a crosslinking agent. The acrylate copolymer base adhesive is prepared through a staged polymerization process. The raw material composition, by mass percentage, includes: 37.5 parts isooctyl acrylate, 12.5 parts butyl acrylate, 10 parts methyl methacrylate, 4.5 parts acrylonitrile, 1.5 parts acrylic acid, 1.0 part hydroxyethyl acrylate, 17.5 parts toluene, 22.5 parts ethyl acetate, and 0.45 parts benzoyl peroxide. The tackifying resin is a rosin-modified resin with a softening point of 92.5℃, added at 15% of the solid content of the acrylate copolymer base adhesive. The crosslinking agent is aluminum acetylacetonate, added at 0.2% of the solid content of the acrylate copolymer base adhesive. (1) Synthesis of acrylate copolymer base adhesive; 70% of the total amount of toluene and ethyl acetate was added to the reaction vessel as the initial solvent, and then 40% of the total amount of isooctyl acrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and benzoyl peroxide was added; nitrogen was introduced to replace the air in the vessel for 20 min, maintaining a slight positive pressure, stirring was started and the stirring speed was set to 150 rpm; the temperature was slowly raised to 95℃ and reacted under reflux for 2 h; (2) Mix methyl methacrylate, acrylonitrile, and the remaining 30% of toluene and ethyl acetate evenly, and then add 30% of the total amount of benzoyl peroxide to prepare a hard monomer mixture. Add the mixture dropwise to the reactor at a uniform flow rate over 2 hours, maintain the reaction temperature at 95°C and continue reflux, and keep the stirring speed constant. After the dropwise addition is complete, add the remaining 30% of benzoyl peroxide and continue to keep the temperature for 3 hours. Then lower the temperature of the reactor to 85°C and keep it at a constant temperature for 4 hours to ensure that the polymerization reaction is complete. Finally, cool to room temperature and discharge the material to obtain the acrylate copolymer base rubber. (3) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 15 parts of rosin-modified tackifying resin, add 0.2 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s. Stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (4) Select aluminum foil substrate with a thickness of 0.05 mm, the surface of which has not been pre-coated; apply pressure-sensitive adhesive evenly to the bright surface of the aluminum foil by scraping, the dry adhesive thickness is 45 μm, the coating speed is 7 m / min; after coating, the aluminum foil enters the oven, which is divided into three temperature zones: the first temperature zone is 3 m long and the temperature is 85℃, the second temperature zone is 3 m long and the temperature is 100℃, and the third temperature zone is 4 m long and the temperature is 115℃, the total drying time is 3 min; after exiting the oven, it is wound up by a winding device, the winding tension is set to 8 N; (5) Place the rolled aluminum foil tape at 23°C for 48 hours to allow the cross-linking reaction in the adhesive layer to proceed fully before slitting and packaging. Example 4

[0024] The pressure-sensitive adhesive is composed of an acrylate copolymer base adhesive, a tackifying resin, and a crosslinking agent. The acrylate copolymer base adhesive is prepared through a staged polymerization process. The raw material composition, by mass percentage, includes: 38.75 parts isooctyl acrylate, 13.75 parts butyl acrylate, 11 parts methyl methacrylate, 5.25 parts acrylonitrile, 1.75 parts acrylic acid, 1.25 parts hydroxyethyl acrylate, 18.75 parts toluene, 23.75 parts ethyl acetate, and 0.525 parts benzoyl peroxide. The tackifying resin is a rosin-modified resin with a softening point of 93.75℃, added at 16.5% of the acrylate copolymer base adhesive's solid content. The crosslinking agent is aluminum acetylacetonate, added at 0.25% of the acrylate copolymer base adhesive's solid content. (1) Synthesis of acrylate copolymer base adhesive; 70% of the total amount of toluene and ethyl acetate was added to the reaction vessel as the initial solvent, and then 40% of the total amount of isooctyl acrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and benzoyl peroxide was added; nitrogen was introduced to replace the air in the vessel for 20 min, maintaining a slight positive pressure, stirring was started and the stirring speed was set to 150 rpm; the temperature was slowly raised to 95℃ and reacted under reflux for 2 h; (2) Mix methyl methacrylate, acrylonitrile, and the remaining 30% of toluene and ethyl acetate evenly, and then add 30% of the total amount of benzoyl peroxide to prepare a hard monomer mixture. Add the mixture dropwise to the reactor at a uniform flow rate over 2 hours, maintain the reaction temperature at 95°C and continue reflux, and keep the stirring speed constant. After the dropwise addition is complete, add the remaining 30% of benzoyl peroxide and continue to keep the temperature for 3 hours. Then lower the temperature of the reactor to 85°C and keep it at a constant temperature for 4 hours to ensure that the polymerization reaction is complete. Finally, cool to room temperature and discharge the material to obtain the acrylate copolymer base rubber. (3) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 16.5 parts of rosin-modified tackifying resin, add 0.25 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s. Stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (4) Select aluminum foil substrate with a thickness of 0.05 mm, the surface of which has not been pre-coated; apply pressure-sensitive adhesive evenly to the bright surface of the aluminum foil by scraping, the dry adhesive thickness is 47.5 μm, the coating speed is 8 m / min; after coating, the aluminum foil enters the drying oven, which is divided into three temperature zones: the first temperature zone is 3 m long and the temperature is 85℃, the second temperature zone is 3 m long and the temperature is 100℃, and the third temperature zone is 4 m long and the temperature is 115℃, the total drying time is 3 min; after exiting the drying oven, it is wound up by a winding device, the winding tension is set to 8 N; (5) Place the rolled aluminum foil tape at 23°C for 48 hours to allow the cross-linking reaction in the adhesive layer to proceed fully before slitting and packaging. Example 5

[0025] The pressure-sensitive adhesive is composed of an acrylate copolymer base adhesive, a tackifying resin, and a crosslinking agent. The acrylate copolymer base adhesive is prepared through a staged polymerization process. The raw material composition, by mass percentage, includes: 40 parts isooctyl acrylate, 15 parts butyl acrylate, 12 parts methyl methacrylate, 6 parts acrylonitrile, 2 parts acrylic acid, 1.5 parts hydroxyethyl acrylate, 20 parts toluene, 25 parts ethyl acetate, and 0.6 parts benzoyl peroxide. The tackifying resin is a rosin-modified resin with a softening point of 95℃, added at 18% of the acrylate copolymer base adhesive's solid content. The crosslinking agent is aluminum acetylacetonate, added at 0.3% of the acrylate copolymer base adhesive's solid content. (1) Synthesis of acrylate copolymer base adhesive; 70% of the total amount of toluene and ethyl acetate was added to the reaction vessel as the initial solvent, and then 40% of the total amount of isooctyl acrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and benzoyl peroxide was added; nitrogen was introduced to replace the air in the vessel for 20 min, maintaining a slight positive pressure, stirring was started and the stirring speed was set to 150 rpm; the temperature was slowly raised to 95℃ and reacted under reflux for 2 h; (2) Mix methyl methacrylate, acrylonitrile, and the remaining 30% of toluene and ethyl acetate evenly, and then add 30% of the total amount of benzoyl peroxide to prepare a hard monomer mixture. Add the mixture dropwise to the reactor at a uniform flow rate over 2 hours, maintain the reaction temperature at 95°C and continue reflux, and keep the stirring speed constant. After the dropwise addition is complete, add the remaining 30% of benzoyl peroxide and continue to keep the temperature for 3 hours. Then lower the temperature of the reactor to 85°C and keep it at a constant temperature for 4 hours to ensure that the polymerization reaction is complete. Finally, cool to room temperature and discharge the material to obtain the acrylate copolymer base rubber. (3) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 18 parts of rosin-modified tackifying resin, add 0.3 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s. Stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (4) Select aluminum foil substrate with a thickness of 0.05 mm, the surface of which has not been pre-coated; apply pressure-sensitive adhesive evenly to the bright surface of the aluminum foil by scraping, the dry adhesive thickness is 50 μm, the coating speed is 9 m / min; after coating, the aluminum foil enters the oven, which is divided into three temperature zones: the first temperature zone is 3 m long and the temperature is 85℃, the second temperature zone is 3 m long and the temperature is 100℃, and the third temperature zone is 4 m long and the temperature is 115℃, the total drying time is 3 min; after exiting the oven, it is wound up by a winding device, the winding tension is set to 8 N; (5) Place the rolled aluminum foil tape at 23°C for 48 hours to allow the cross-linking reaction in the adhesive layer to proceed fully before slitting and packaging.

[0026] Comparative Example 1 The pressure-sensitive adhesive is composed of an acrylate copolymer base adhesive, a tackifying resin, and a crosslinking agent. The acrylate copolymer base adhesive is produced through a one-step feeding polymerization process. The raw material composition, by mass percentage, includes: 37.5 parts isooctyl acrylate, 12.5 parts butyl acrylate, 10 parts methyl methacrylate, 4.5 parts acrylonitrile, 1.5 parts acrylic acid, 1.0 part hydroxyethyl acrylate, 17.5 parts toluene, 22.5 parts ethyl acetate, and 0.45 parts benzoyl peroxide. The tackifying resin is a rosin-modified resin with a softening point of 92.5℃, added at 15% of the solid content of the acrylate copolymer base adhesive. The crosslinking agent is aluminum acetylacetonate, added at 0.2% of the solid content of the acrylate copolymer base adhesive. (1) Synthesis of acrylate copolymer-based adhesive: All toluene and ethyl acetate were added to the reactor as solvents, followed by all isooctyl acrylate, butyl acrylate, methyl methacrylate, acrylonitrile, acrylic acid, hydroxyethyl acrylate and all benzoyl peroxide; nitrogen was introduced to replace the air in the reactor for 20 min, maintaining a slight positive pressure, stirring was started and the stirring speed was set to 150 rpm; the temperature was slowly raised to 95℃ and reacted under reflux for 5 h; then the temperature of the reactor was lowered to 85℃ and kept at a constant temperature for 4 h to ensure complete polymerization; finally, the mixture was cooled to room temperature and discharged to obtain acrylate copolymer-based adhesive; (2) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 15 parts of rosin-modified tackifying resin, add 0.2 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s. Stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (3) Select aluminum foil substrate with a thickness of 0.05 mm, the surface of which has not been pre-coated; apply pressure-sensitive adhesive evenly to the bright surface of the aluminum foil by scraping, the dry adhesive thickness is 45 μm, the coating speed is 7 m / min; after coating, the aluminum foil enters the oven, which is divided into three temperature zones: the first temperature zone is 3 m long and the temperature is 85℃, the second temperature zone is 3 m long and the temperature is 100℃, and the third temperature zone is 4 m long and the temperature is 115℃, the total drying time is 3 min; after exiting the oven, it is wound up by a winding device, the winding tension is set to 8 N; (4) Place the rolled aluminum foil tape at 23°C for 48 hours to allow the cross-linking reaction in the adhesive layer to proceed fully before slitting and packaging.

[0027] Comparative Example 2 The pressure-sensitive adhesive is composed of an acrylate copolymer base adhesive, a tackifying resin, and a crosslinking agent. The acrylate copolymer base adhesive is prepared through a staged polymerization process. The raw material composition, by mass percentage, includes: 47.5 parts isooctyl acrylate, 17.5 parts butyl acrylate, 1.5 parts acrylic acid, 1.0 part hydroxyethyl acrylate, 17.5 parts toluene, 22.5 parts ethyl acetate, and 0.45 parts benzoyl peroxide. The tackifying resin is a rosin-modified resin with a softening point of 92.5℃, added at 15% of the solid content of the acrylate copolymer base adhesive. The crosslinking agent is aluminum acetylacetonate, added at 0.2% of the solid content of the acrylate copolymer base adhesive. (1) Synthesis of acrylate copolymer base adhesive; 70% of the total amount of toluene and ethyl acetate was added to the reaction vessel as the initial solvent, and then 40% of the total amount of isooctyl acrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and benzoyl peroxide was added; nitrogen was introduced to replace the air in the vessel for 20 min, maintaining a slight positive pressure, stirring was started and the stirring speed was set to 150 rpm; the temperature was slowly raised to 95℃ and reacted under reflux for 2 h; (2) The remaining 30% of toluene and ethyl acetate were mixed with 30% of the total amount of benzoyl peroxide and added dropwise to the reactor over 2 hours at a uniform flow rate. The reaction temperature was maintained at 95°C and refluxed continuously, while the stirring speed remained constant. After the addition was completed, the remaining 30% of benzoyl peroxide was added and the reaction was continued at the temperature for 3 hours. Then the temperature of the reactor was lowered to 85°C and kept at the temperature for 4 hours to ensure the polymerization reaction was complete. Finally, the mixture was cooled to room temperature and discharged to obtain the acrylate copolymer base rubber. (3) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 15 parts of rosin-modified tackifying resin, add 0.2 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s. Stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (4) The coating and curing steps are the same as in Example 3.

[0028] Comparative Example 3 The pressure-sensitive adhesive is composed of an acrylic copolymer base adhesive and a tackifying resin, and does not contain a metal crosslinking agent. The acrylic copolymer base adhesive is prepared by a staged polymerization process, and the raw material composition is the same as in Example 3; the tackifying resin is a rosin-modified resin with a softening point of 110°C, and its addition amount is 25% relative to the solid content of the acrylic copolymer base adhesive. (1) The synthesis of the acrylate copolymer-based adhesive is the same as in Example 3; (2) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 25 parts of rosin-modified tackifying resin with a softening point of 110℃, without adding crosslinking agent, and add an appropriate amount of ethyl acetate to adjust the viscosity, control the viscosity at 3000 mPa·s at 25℃, stir at 100 rpm for 1 h until the resin is completely dissolved and evenly dispersed to obtain pressure-sensitive adhesive; (3) The coating and curing steps are the same as in Example 3.

[0029] Example of effect Table 1 below shows the performance analysis results of a low-temperature resistant aluminum foil tape using Examples 1 to 5 and Comparative Examples 1 to 3 of the present invention.

[0030] Table 1

[0031] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A low-temperature resistant aluminum foil tape, characterized in that, The pressure-sensitive adhesive is composed of an acrylic copolymer-based adhesive, a tackifying resin, and a crosslinking agent; Acrylic copolymer-based adhesives are prepared through a staged polymerization process, and the raw material composition, by mass percentage, includes: 35-40 parts of isooctyl acrylate 10-15 parts butyl acrylate 8-12 parts of methyl methacrylate 3-6 parts acrylonitrile 1-2 parts acrylic acid Hydroxyethyl acrylate 0.5-1.5 parts 15-20 parts of toluene 20-25 parts of ethyl acetate 0.3-0.6 parts of benzoyl peroxide.

2. The low-temperature resistant aluminum foil tape according to claim 1, characterized in that, The tackifying resin is selected from rosin-modified resin with a softening point of 90-95℃, and its addition amount is 12-18% relative to the solid content of acrylate copolymer-based adhesive.

3. The low-temperature resistant aluminum foil tape according to claim 1, characterized in that, The crosslinking agent is aluminum acetylacetonate, and the amount added is 0.1-0.3% relative to the solid content of the acrylate copolymer base.

4. A method for preparing a low-temperature resistant aluminum foil tape, characterized in that, The preparation steps include the following: (1) Add 70% of the total amount of toluene and ethyl acetate to the reactor as the initial solvent, and then add 40% of the total amount of isooctyl acrylate, butyl acrylate, acrylic acid, hydroxyethyl acrylate and benzoyl peroxide; purge the reactor with inert gas for 20 min, and stir under slight positive pressure; slowly raise the temperature and react under reflux for 2 h; (2) Mix methyl methacrylate, acrylonitrile, and the remaining 30% of toluene and ethyl acetate evenly, and then add 30% of the total amount of benzoyl peroxide to prepare a hard monomer mixture. Add the mixture dropwise to the reactor at a uniform flow rate over 2 hours, maintain the reaction temperature and continue reflux, and keep the stirring speed constant. After the dropwise addition is complete, add the remaining 30% of benzoyl peroxide and continue to keep the temperature for 3 hours. Then, cool the reactor and keep it at a constant temperature for 4 hours to ensure that the polymerization reaction is complete. Finally, cool to room temperature and discharge the material to obtain the acrylate copolymer base rubber. (3) Take 100 parts of the above acrylate copolymer base adhesive by solid content, add 12-18 parts of rosin-modified tackifying resin, add 0.1-0.3 parts of aluminum acetylacetonate, and add an appropriate amount of ethyl acetate to adjust the viscosity. Control the viscosity at 25°C to 3000 mPa·s, stir at 100 rpm for 1 hour until the resin is completely dissolved and all components are evenly dispersed to obtain pressure-sensitive adhesive. (4) Select aluminum foil substrate with no base coating treatment; apply pressure-sensitive adhesive evenly to the glossy surface of the aluminum foil using a scraper coating method, with a dry adhesive thickness of 40-50μm; after coating, the aluminum foil enters the drying oven, which is divided into three temperature zones: the first temperature zone is 3m long and the temperature is 85℃, the second temperature zone is 3m long and the temperature is 100℃, and the third temperature zone is 4m long and the temperature is 115℃, with a total drying time of 3min; after exiting the drying oven, the foil is wound up by a winding device with a winding tension set to 8N; (5) Place the rolled aluminum foil tape at 23°C for 48 hours to allow the cross-linking reaction in the adhesive layer to proceed fully before slitting and packaging.

5. The method for preparing a low-temperature resistant aluminum foil tape according to claim 4, characterized in that, The inert gas in step (1) is nitrogen.

6. The method for preparing a low-temperature resistant aluminum foil tape according to claim 4, characterized in that, The stirring speed in step (1) is 150 rpm.

7. The method for preparing a low-temperature resistant aluminum foil tape according to claim 4, characterized in that, In step (1), the temperature is raised to 95°C.

8. The method for preparing a low-temperature resistant aluminum foil tape according to claim 4, characterized in that, In step (2), the temperature drops to 85°C.

9. The method for preparing a low-temperature resistant aluminum foil tape according to claim 4, characterized in that, The thickness of the aluminum foil substrate in step (4) is 0.05 mm.

10. The method for preparing a low-temperature resistant aluminum foil tape according to claim 4, characterized in that, The coating speed in step (4) is 5-9 m / min.

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