High-temperature-resistant reusable protective adhesive tape

Abstract

The invention discloses a high-temperature-resistant reusable protective adhesive tape and a preparation method thereof. The adhesive tape takes polyisoprene rubber as a main body material, epoxy resin is modified through a polyimide prepolymer, and cohesion is increased through a silane coupling agent; the preparation method comprises the following steps: firstly synthesizing a polyimide prepolymer, then preparing the modified epoxy resin, mixing the modified epoxy resin with the rubber and a plurality of auxiliaries in an open mill, and curing under specific conditions. The protective adhesive tape prepared by the invention has no adverse change in appearance, can be applied to industrial high-temperature processing, can be reused, and solves the problems of high-temperature resistance and reuse of the adhesive tape such as scratch prevention and stripping prevention in product processing.

Description

Technical Field

[0001] The present invention relates to the technical field of adhesive adhesives, and particularly to a high-temperature resistant and reusable protective tape. Background Art

[0002] In the process of industrial production, some product processing links such as scratch prevention, pollution prevention, grinding fixation, and cutting fixation often require the assistance of protective tapes. At room temperature, the tapes all have good adhesive strength. During the processing, high-temperature operations are required. After completion, the tape is peeled off at high temperature. The adhesive force of the tape depends on the van der Waals force between the adhesive layer and the interface of the material to be protected. When the temperature rises, the movement of the pressure-sensitive adhesive molecules intensifies, and the corresponding adhesive strength will decrease.

[0003] CN114456729A synthesizes mica paper with benzoyl peroxide coated on both sides, coats the first and second adhesives after standing, and realizes semi-curing by heating and drying; then composites with mica paper coated with the second adhesive, and the release paper coated with fluorosilicone release agent is cured and then composites with mica paper coated with the first adhesive, and the obtained high-temperature resistant and reusable mica tape has excellent comprehensive performance, can withstand high temperature and be reused multiple times. Due to the excellent comprehensive performance of this invention, its process is complex and the cost is relatively high. The present invention emerges as the times require, with polyisoprene rubber as the core, combined with modified epoxy resin to increase the cohesion of the adhesive layer, prevent residual glue during high-temperature peeling, meet the high-efficiency and economic requirements of industrial production, and has broad application prospects. Summary of the Invention

[0004] In view of the above-mentioned defects of the prior art, the present invention takes polyisoprene rubber as the core, combines with polyimide prepolymer modified epoxy resin and other additives to invent a protective tape, providing a solution for the subsequent processing and protection of products.

[0005] A high-temperature resistant and reusable protective tape is composed of the following components in parts by mass: 30-80 parts of polyisoprene rubber, 5-10 parts of modified epoxy resin, 0.1-0.2 parts of zinc oxide, 1-3 parts of nano calcium carbonate, 0.1-0.2 parts of stearic acid, 1-3 parts of silane coupling agent, 0.3-0.8 parts of polypropylene, and 0.1-0.2 parts of naphthenic oil.

[0006] The preparation method of a high-temperature resistant and reusable protective tape comprises the following steps: adding 30-80 parts of polyisoprene rubber, 5-10 parts of modified epoxy resin, 0.1-0.2 parts of zinc oxide, 1-3 parts of nano calcium carbonate, 0.1-0.2 parts of stearic acid, and 1-3 parts of silane coupling agent into an open mill in sequence, mixing at 50-80 °C for 10-30 min; adding 0.1-0.2 parts of naphthenic oil and 0.3-0.8 parts of polypropylene melted at 180-190 °C respectively, and continuing to mix at 50-80 °C for 3-8 min; performing calendering and forming, and controlling the thickness of the adhesive layer to be 130±10 μm, thus obtaining the high-temperature resistant and reusable protective tape.

[0007] The silane coupling agent is any one of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-aminopropyltriethoxysilane, and 3-glycidyletheroxypropyltrimethoxysilane.

[0008] Most preferably, the silane coupling agent involved in the present invention is 3-(2,3-epoxypropoxy)propyltrimethoxysilane. The preparation method of the modified epoxy resin is as follows: dissolving 300-800 g of polyimide prepolymer in 0.5-1 L of N,N-dimethylacetamide, adding 300-800 g of epoxy resin, stirring at 1000-3000 r / min for 1-2 h, dispersing by 800-1000 W ultrasonic wave for 1-3 h, then drying in vacuum at 100-110 °C for 2-4 h and cooling to room temperature.

[0009] The epoxy resin is any one of bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, and phenolic type epoxy resin.

[0010] Preferably, the epoxy resin involved in the present invention is bisphenol A type epoxy resin.

[0011] Preferably, the preparation method of the polyimide prepolymer is as follows: mixing 0.5-2 mol of aromatic diamine compounds, 0.5-2 mol of 4,4-biphenylether dianhydride, and 0.5-1 L of N,N-dimethylacetamide, stirring at 300-500 r / min for 1-5 h, adding 5-10 g of catalyst and 20-50 g of phenylacetylene phthalic anhydride, heating at 100-120 °C for 8-10 h, filtering while it is hot to obtain the precipitate, rinsing with ethanol, and drying to obtain the polyimide prepolymer.

[0012] The aromatic diamine compounds involved in the preparation method of the polyimide prepolymer include any one of 1,4-bis(2,4-diaminophenoxy)benzene, 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, and 4,4'-diaminodiphenylsulfone.

[0013] In the preparation method of the polyimide prepolymer, the catalysts involved are organic base catalysts and / or metal catalysts; the organic base catalyst is triethylamine, and the metal catalyst is one of zirconium acetylacetonate, nickel acetylacetonate, and iron tetroxide.

[0014] Advantages of the present invention: 1. Compared with the prior art, the polyimide prepolymer modifies the epoxy resin to construct a stable network structure, greatly improving the high-temperature resistance and cohesion performance of the tape, and ensuring good repeated use effect.

[0015] 2. The preferred catalyst for modifying the epoxy resin in the present invention is a metal catalyst, which accurately activates the active groups and optimizes the network structure. The introduction of iron tetroxide in the present invention is relatively scarce in the related fields of the prior art, effectively enhancing the high-temperature stability, adhesion and flexibility of the tape, and expanding the application boundary of high-temperature processing.

[0016] 3. The protective tape prepared in the present invention adds nano-calcium carbonate, which is uniformly dispersed in the adhesive layer to enhance the rigidity and cohesion of the system, stabilize the adhesive structure to prevent viscosity fluctuations, reduce the viscosity loss during repeated use, effectively ensure that the tape can stably play a protective effect under complex working conditions for a long time, maintain reliable adhesion and repeated use characteristics, reduce industrial costs, and improve production efficiency and product quality. Specific embodiments

[0017] A high-temperature resistant and reusable protective tape is composed of the following components in parts by mass: 30-80 parts of polyisoprene rubber, 5-10 parts of modified epoxy resin, 0.1-0.2 parts of zinc oxide, 1-3 parts of nano-calcium carbonate, 0.1-0.2 parts of stearic acid, 1-3 parts of silane coupling agent, 0.3-0.8 parts of polypropylene, and 0.1-0.2 parts of naphthenic oil. Its preparation method includes the following steps: sequentially add polyisoprene rubber, modified epoxy resin, zinc oxide, nano-calcium carbonate, stearic acid, and silane coupling agent into an open mill, and mix at 50-80 °C for 10-30 min; respectively add naphthenic oil and polypropylene melted at 180-190 °C, and continue to mix at 50-80 °C for 3-8 min; under the environment with a relative humidity of 40-60% and a temperature of 20-30 °C, calender and form, control the thickness of the adhesive layer to be 130 ± 10 μm, and place for 48 h to obtain.

[0018] The preparation method of the above-mentioned modified epoxy resin is as follows: dissolve 300-800 g of polyimide prepolymer in 0.5-1 L of N,N-dimethylacetamide, add 300-800 g of epoxy resin, stir at 1000-3000 r / min for 1-2 h, disperse the solvent with 800-1000 W ultrasonic waves for 1-3 h, then vacuum dry at 100-110 °C for 2-4 h and cool to room temperature.

[0019] The preparation method of the above polyimide prepolymer is as follows: Mix 0.5 - 2 mol of aromatic diamine compounds, 0.5 - 2 mol of 4,4'-biphenylether dianhydride, and 0.5 - 1 L of N,N-dimethylacetamide, stir at 300 - 500 r / min for 1 - 5 h, add 5 - 10 g of catalyst and 20 - 50 g of phenylacetylene phthalic anhydride, heat at 100 - 120 °C for 8 - 10 h, filter while it is hot to obtain the precipitate, wash with ethanol, and dry to obtain the polyimide prepolymer.

[0020] Aromatic diamine compounds are important monomers for polymerization reactions. Containing two amino groups, they undergo polycondensation reactions with the anhydride groups in dianhydride monomers. During the reaction, the lone pair electrons on the nitrogen atom of the amino group attack the carbonyl carbon of the anhydride, triggering a ring-opening reaction and forming amide bonds in the polyimide molecular chain.

[0021] The ether bond in the molecular structure of 4,4'-biphenylether dianhydride can increase the flexibility of the molecular chain. The presence of the biphenylether structure endows polyimide with some special properties, making polyimide have better processing performance.

[0022] For phenylacetylene phthalic anhydride, the phenylacetylene group in its molecular structure can introduce unsaturated bonds into the polyimide molecular chain, enhance the compatibility between the polyimide prepolymer and epoxy resin, and improve the comprehensive properties of the modified epoxy resin.

[0023] The parameters and sources of some raw materials in the examples are as follows: Bisphenol A epoxy resin: Model: EPIKOTE™ 6520-WH-53A; Hexion.

[0024] Phenylacetylene phthalic anhydride: Abbreviation: PEPA; CAS No.: 119389-05-8.

[0025] 3-(2,3-Epoxypropoxy)propyltrimethoxysilane: Silane coupling agent KH-560.

[0026] 1,4-Bis(2,4-diaminophenoxy)benzene: CAS No.: 1041928-17-9.

[0027] Polypropylene: Model: Flow PP3655E1; ExxonMobil.

[0028] Polyisoprene rubber, Model: IIR2200; Zeon Corporation.

[0029] Nano calcium carbonate, particle size 50 nm.

[0030] Example 1 A preparation method of a high-temperature resistant and reusable protective tape is as follows: Take 5 kg of polyisoprene rubber, 0.8 kg of modified epoxy resin, 0.1 kg of zinc oxide, 0.2 kg of nano calcium carbonate, 0.01 kg of stearic acid, and 0.2 kg of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and add them into an open mill in sequence. After kneading at 60 °C for 15 min; add 0.05 kg of polypropylene and 0.01 kg of naphthenic oil melted and plasticized at 190 °C, and continue kneading for 5 min; under the environment with a relative humidity of 40 - 60% and a temperature of 20 - 30 °C, calender and form, control the thickness of the rubber layer to be 130 ± 10 μm, and let it stand for 48 h to obtain the product.

[0031] The preparation method of the above-mentioned modified epoxy resin is as follows: Take 500 g of polyimide prepolymer and dissolve it in 1 L of N,N-dimethylacetamide, add 500 g of bisphenol A type epoxy resin, stir at 2000 r / min for 2 h, disperse with 1000 W ultrasonic wave for 2 h, then dry in vacuum at 110 °C for 4 h and cool to room temperature to obtain it.

[0032] The preparation method of the above-mentioned polyimide prepolymer is as follows: Mix 1 mol of 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, 1 mol of 4,4-biphenylene ether dianhydride and 1 L of N,N-dimethylacetamide, stir at 500 r / min for 3 h, add 2 g of triethylamine and 30 g of phenylethynyl phthalic anhydride, heat at 120 °C for 10 h, filter while it is hot to obtain the precipitate, wash it repeatedly with 1 L of ethanol, and dry it in an oven at 60 °C for 2 h to obtain the product.

[0033] Comparative Example 1 A preparation method of a high-temperature resistant and reusable protective tape is as follows: Take 5 kg of polyisoprene rubber, 0.8 kg of bisphenol A type epoxy resin, 0.01 kg of zinc oxide, 0.2 kg of nano calcium carbonate, 0.01 kg of stearic acid, and 0.2 kg of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and add them into an open mill in sequence. After kneading at 60 °C for 15 min; add 0.05 kg of polypropylene and 0.01 kg of naphthenic oil melted and plasticized at 190 °C, and continue kneading for 5 min; under the environment with a relative humidity of 40 - 60% and a temperature of 20 - 30 °C, calender and form, control the thickness of the rubber layer to be 130 ± 10 μm, and let it stand for 48 h to obtain the product.

[0034] Example 2 A preparation method of a high-temperature resistant and reusable protective tape is as follows: Take 5 kg of polyisoprene rubber, 0.8 kg of modified epoxy resin, 0.01 kg of zinc oxide, 0.2 kg of nano calcium carbonate, 0.01 kg of stearic acid, and 0.2 kg of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and add them to the open mill in sequence. After kneading at 60 °C for 15 min, add 0.05 kg of polypropylene and 0.01 kg of naphthenic oil that are melted and plasticized at 190 °C, and continue kneading for 5 min. Under the environment with a relative humidity of 40 - 60% and a temperature of 20 - 30 °C, calender and form, control the thickness of the rubber layer to be 130 ± 10 μm, and let it stand for 48 h to obtain the product.

[0035] The preparation method of the above-mentioned modified epoxy resin is as follows: Take 500 g of polyimide prepolymer and dissolve it in 1 L of N,N-dimethylacetamide, add 500 g of bisphenol A type epoxy resin, stir at 2000 r / min for 2 h, disperse the solvent with 1000 W ultrasonic waves for 2 h, then dry it in vacuum at 110 °C for 4 h and cool it to room temperature to obtain the product.

[0036] The preparation method of the above-mentioned polyimide prepolymer is as follows: Mix 1 mol of 4,4'-diaminodiphenyl sulfone, 1 mol of 4,4-biphenylene ether dianhydride and 1 L of N,N-dimethylacetamide, stir at 500 r / min for 3 h, add 2 g of triethylamine and 30 g of phenyl ethynyl phthalic anhydride, heat at 120 °C for 10 h, filter while it is hot to obtain the precipitate, repeatedly rinse it with 1 L of ethanol, and dry it in an oven at 60 °C for 2 h to obtain the product.

[0037] Example 3 A preparation method of a high-temperature resistant and reusable protective tape is as follows: Take 5 kg of polyisoprene rubber, 0.8 kg of modified epoxy resin, 0.01 kg of zinc oxide, 0.2 kg of nano calcium carbonate, 0.01 kg of stearic acid, and 0.2 kg of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and add them to the open mill in sequence. After kneading at 60 °C for 15 min, add 0.05 kg of polypropylene and 0.01 kg of naphthenic oil that are melted and plasticized at 190 °C, and continue kneading for 5 min. Under the environment with a relative humidity of 40 - 60% and a temperature of 20 - 30 °C, calender and form, control the thickness of the rubber layer to be 130 ± 10 μm, and let it stand for 48 h to obtain the product.

[0038] The preparation method of the above-mentioned modified epoxy resin is as follows: Take 500 g of polyimide prepolymer and dissolve it in 1 L of N,N-dimethylacetamide, add 500 g of bisphenol A type epoxy resin, stir at 2000 r / min for 2 h, disperse the solvent with 1000 W ultrasonic waves for 2 h, then dry it in vacuum at 110 °C for 4 h and cool it to room temperature to obtain the product.

[0039] The preparation method of the above polyimide prepolymer is as follows: Mix 1 mol of 1,4-bis(2,4-diaminophenoxy)benzene, 1 mol of 4,4'-biphenylether dianhydride and 1 L of N,N-dimethylacetamide, stir at 500 r / min for 3 h, add 2 g of triethylamine and 30 g of phenylacetylenephthalic anhydride, heat at 120 °C for 10 h, filter while it is hot to obtain the precipitate, repeatedly rinse with 1 L of ethanol, and dry in an oven at 60 °C for 2 h to obtain the product.

[0040] Example 4 The preparation method of a high-temperature resistant and reusable protective tape is as follows: Add 5 kg of polyisoprene rubber, 0.8 kg of modified epoxy resin, 0.01 kg of zinc oxide, 0.2 kg of nano calcium carbonate, 0.01 kg of stearic acid, and 0.2 kg of 3-(2,3-epoxypropoxy)propyltrimethoxysilane into an open mill in sequence. After mixing at 60 °C for 15 min, add 0.05 kg of polypropylene and 0.01 kg of naphthenic oil melted and plasticized at 190 °C, and continue to mix for 5 min. Under the environment with a relative humidity of 40 - 60% and a temperature of 20 - 30 °C, carry out calendering and molding, control the thickness of the adhesive layer to be 130 ± 10 μm, and let it stand for 48 h to obtain the product.

[0041] The preparation method of the above modified epoxy resin is as follows: Dissolve 500 g of polyimide prepolymer in 1 L of N,N-dimethylacetamide, add 500 g of bisphenol A type epoxy resin, stir at 2000 r / min for 2 h and disperse the solvent with 1000 W ultrasonic waves for 2 h, then dry in vacuum at 110 °C for 4 h and cool to room temperature to obtain the product.

[0042] The preparation method of the above polyimide prepolymer is as follows: Mix 1 mol of 1,4-bis(2,4-diaminophenoxy)benzene, 1 mol of 4,4'-biphenylether dianhydride and 1 L of N,N-dimethylacetamide, stir at 500 r / min for 3 h, add 2 g of zirconium acetylacetonate and 30 g of phenylacetylenephthalic anhydride, heat at 120 °C for 10 h, filter while it is hot to obtain the precipitate, repeatedly rinse with 1 L of ethanol, and dry in an oven at 60 °C for 2 h to obtain the product.

[0043] Example 5 The preparation method of a high-temperature resistant and reusable protective tape is as follows: Take 5 kg of polyisoprene rubber, 0.8 kg of modified epoxy resin, 0.01 kg of zinc oxide, 0.2 kg of nano calcium carbonate, 0.01 kg of stearic acid, and 0.2 kg of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and add them to the open mill in sequence. After kneading at 60 °C for 15 min, add 0.05 kg of polypropylene and 0.01 kg of naphthenic oil that are melt-plasticized at 190 °C, and continue kneading for 5 min. Under the environment with a relative humidity of 40 - 60% and a temperature of 20 - 30 °C, calender and form, control the thickness of the rubber layer to be 130 ± 10 μm, and let it stand for 48 h to obtain the product.

[0044] The preparation method of the above-mentioned modified epoxy resin is as follows: Take 500 g of polyimide prepolymer and dissolve it in 1 L of N,N-dimethylacetamide, add 500 g of bisphenol A epoxy resin, stir at 2000 r / min for 2 h, disperse the solvent with 1000 W ultrasonic waves for 2 h, then dry in vacuum at 110 °C for 4 h and cool to room temperature to obtain the product.

[0045] The preparation method of the above-mentioned polyimide prepolymer is as follows: Mix 1 mol of 1,4-bis(2,4-diaminophenoxy)benzene, 1 mol of 4,4-biphenylene ether dianhydride and 1 L of N,N-dimethylacetamide, stir at 500 r / min for 3 h, add 2 g of nickel acetylacetonate and 30 g of phenylethynyl phthalic anhydride, heat at 120 °C for 10 h, filter while it is hot to obtain the precipitate, wash it repeatedly with 1 L of ethanol, and dry it in an oven at 60 °C for 2 h to obtain the product.

[0046] Example 6 A preparation method of a high-temperature resistant and reusable protective tape is as follows: Take 5 kg of polyisoprene rubber, 0.8 kg of modified epoxy resin, 0.01 kg of zinc oxide, 0.2 kg of nano calcium carbonate, 0.01 kg of stearic acid, and 0.2 kg of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and add them to the open mill in sequence. After kneading at 60 °C for 15 min, add 0.05 kg of polypropylene and 0.01 kg of naphthenic oil that are melt-plasticized at 190 °C, and continue kneading for 5 min. Under the environment with a relative humidity of 40 - 60% and a temperature of 20 - 30 °C, calender and form, control the thickness of the rubber layer to be 130 ± 10 μm, and let it stand for 48 h to obtain the product.

[0047] The preparation method of the above-mentioned modified epoxy resin is as follows: Take 500 g of polyimide prepolymer and dissolve it in 1 L of N,N-dimethylacetamide, add 500 g of bisphenol A epoxy resin, stir at 2000 r / min for 2 h, disperse the solvent with 1000 W ultrasonic waves for 2 h, then dry in vacuum at 110 °C for 4 h and cool to room temperature to obtain the product.

[0048] The preparation method of the above polyimide prepolymer is as follows: Mix 1 mol of 1,4-bis(2,4-diaminophenoxy)benzene, 1 mol of 4,4'-biphenylene ether dianhydride and 1 L of N,N-dimethylacetamide, stir at 500 r / min for 3 h, add 2 g of iron oxide and 30 g of phenylethynyl phthalic anhydride, heat at 120 °C for 10 h, filter while it is hot to obtain the precipitate, wash it repeatedly with 1 L of ethanol, and dry it in an oven at 60 °C for 2 h to obtain the product.

[0049] Test Example 1 Adhesion test The initial adhesion was tested according to GB / T 4852-2002 Test method for initial tack of pressure-sensitive adhesive tapes (rolling ball method). Requirements: The rolling ball of the initial adhesion > 9#; The holding adhesion was tested according to the test method of GB / T 4851-2014 Adhesive tapes - Determination of holding power, and the temperature was set at (80 ± 5) °C. The results are shown in Table 1.

[0050] Table 1 Adhesion test results

[0051] In Comparative Example 1, only bisphenol A epoxy resin was used, while in Examples 1-6, an epoxy resin modified with a polyimide prepolymer was used. The polyimide itself has excellent thermal stability and mechanical properties. During the modification of the epoxy resin, the polyimide prepolymer interacted with the epoxy resin, and an interpenetrating network structure might have been formed, enabling the adhesive layer to better disperse stress when subjected to external forces, thus improving the cohesive strength of the tape. At the same time, the addition of the polyimide might also have improved the flexibility of the epoxy resin, enabling the tape to better conform when contacting the surface of the adherend, thereby increasing the initial adhesion. In a high-temperature environment, the polyimide can maintain its structural stability, prevent the tape from softening, and thus improve the holding adhesion.

[0052] Among the comparison of the adhesion results of Examples 1-3, it might be that the positions and numbers of amino groups and phenoxy groups in the molecular structure of 1,4-bis(2,4-diaminophenoxy)benzene added in Example 3 have an important influence on the synthesis and properties of the polyimide. The amino group is the active site for reacting with the acid anhydride to form the polyimide, and the presence of the phenoxy group might have changed the flexibility and polarity of the polyimide molecular chain.

[0053] In Examples 4 - 6, a further selected metal catalyst activates the reaction of the active groups participating in the polyimide prepolymer with the epoxy groups in the epoxy resin to form an interpenetrating network structure. This structure better maintains viscosity at high temperatures, that is, it improves the holding tack, and at the same time may also improve the initial tack. Compared with the triethylamine used in Examples 1 - 3 which is an organic base catalyst, it mainly promotes the reaction equilibrium to shift towards the direction of polymer formation by neutralizing the generated acid, and reacts with the anhydride as a nucleophile to generate an active intermediate. Therefore, at the moment of contact with the adherend, its molecular chains may not be able to quickly form effective contact and adsorption, resulting in relatively low adhesiveness of the subsequently prepared protective tape. In the preparation process of Example 6, the catalyst selected is iron tetroxide which has variable valence states and can form an electron transfer complex or coordination compound with amino and anhydride groups, enabling the polymerization reaction to be directional and the molecular chain structure of the generated polyimide prepolymer to be more regular, effectively resisting factors unfavorable to performance.

[0054] Test Example 2 Stability test With reference to the peel strength test method of adhesive tapes GB / T 2792 - 2014, the tapes prepared in Examples 1 - 6 and Comparative Example 1 were placed in an accelerated aging test chamber, with the aging temperature set at (120 ± 5) °C and the relative humidity at (85 ± 5) %. After taking them out after 72 h, the 180° peel strength of the test samples was tested; at the same time, whether there were adverse phenomena such as bubbles, delamination, glue overflow, and yellowing after the adhesive liquids prepared in Examples 1 - 6 and Comparative Example 1 were treated was observed to evaluate the high-temperature oxidation resistance of the tapes.

[0055] The high-temperature shrinkage rate refers to the method for measuring the dimensional change of polyethylene terephthalate film for optical functional films after heating in GB / T 27584 - 2011. The tapes prepared in Examples 1 - 6 and Comparative Example 1 were cut out, and the conditions were set at 150 °C and 60 min.

[0056] Table 2 Results of aging resistance test

[0057] Examples 1-6 further enhanced the system stability through the introduction of polyimide. The strong intermolecular interaction of its molecular chains can restrict the movement of epoxy resin molecules at high temperatures, reduce the change in internal stress caused by heat, and inhibit the destruction of the internal structure. Further, compared with the organic base catalysts used in the synthesis of polyimide prepolymers in Examples 1-3, triethylamine added may decompose or volatilize at high temperatures, which may lead to incomplete reactions or an increase in structural defects of the generated polyimide prepolymers, affecting the high-temperature resistance performance of the subsequent protective tape. The protective tapes prepared in Examples 4-6 have better stability in high-temperature environments. This may be because metal catalysts may make the molecular chain structure of the generated polyimide prepolymers more regular, which is beneficial to improving the performance of the tape. Among them, the catalyst used in Example 6 is iron oxide. In a high-temperature oxidation environment, by forming specific reactive intermediates with the electrons of the reactants, it promotes the formation of prepolymers, and this interaction mode may be more suitable for this reaction system than zirconium acetylacetonate, nickel acetylacetonate, or triethylamine, helping to protect the structural integrity of the polyimide prepolymers. Therefore, after the generated polyimide prepolymers are combined with other components such as epoxy resin, they can better play a synergistic role.

[0058] In the subsequent formulation for preparing the protective tape, naphthenic oil is used as a plasticizer and lubricant. During use, it can reduce the frictional loss between the tape and the adherend, relieve the decrease in adhesion caused by stress concentration, moderately migrate between the molecules of the adhesive layer, repair the microscopic structural damage caused by paste peeling, and restore part of the adhesion. It synergistically optimizes the balance of the elastic modulus and toughness of the composite system with polyisoprene rubber and modified epoxy resin components, ensuring that the tape adheres firmly and is not easily detached from the surface of the adherend. Furthermore, it ensures that the tape adheres firmly during industrial high-temperature processing or long-term use, preventing product damage or processing deviation caused by the detachment of the protective tape. Zinc oxide and nano-calcium carbonate are used as fillers to enhance the cohesion of the adhesive layer and slow down the loss of adhesion, avoiding the failure of the adhesion force caused by local stress concentration. The subsequent tape can withstand high-temperature stress and external forces for a long time. Stearic acid improves the processability and compatibility with the adherend, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane coupling enhances the interaction between components and chemical bonding with the adherend. Each component is evenly distributed, interacts with each other, and plays a synergistic role to form a stable three-dimensional network structure, improving the heat resistance of the adhesive layer and the stability between the adhesive layer and the adherend, reducing shrinkage deformation due to heat, enhancing the structural integrity and stability of the adhesive layer, reducing the shrinkage rate, ensuring the stability of the protective tape at high temperatures, and improving the stable performance of the high-temperature resistant and reusable protective tape.

Claims

1. A high-temperature resistant and reusable protective tape, characterized in that, It consists of the following components by mass ratio: 30 - 80 parts of polyisoprene rubber, 5 - 10 parts of modified epoxy resin, 0.1 - 0.2 parts of zinc oxide, 1 - 3 parts of nano calcium carbonate, 0.1 - 0.2 parts of stearic acid, 1 - 3 parts of silane coupling agent, 0.3 - 0.8 parts of polypropylene, and 0.1 - 0.2 parts of naphthenic oil.

2. The high-temperature resistant and reusable protective tape according to claim 1, wherein The preparation method of the modified epoxy resin is as follows: Dissolve 300 - 800 g of polyimide prepolymer in 0.5 - 1 L of N,N - dimethylacetamide, add 300 - 800 g of epoxy resin, stir at 1000 - 3000 r / min for 1 - 2 h, disperse with 800 - 1000 W ultrasonic waves for 1 - 3 h, then conduct vacuum drying at 100 - 110 °C for 2 - 4 h and cool to room temperature to obtain the modified epoxy resin.

3. The high-temperature resistant and reusable protective tape according to claim 2, wherein: The epoxy resin is any one of bisphenol A epoxy resin, brominated bisphenol A epoxy resin, or phenolic epoxy resin.

4. The heat-resistant reusable protective tape according to claim 2, wherein, The preparation method of the polyimide prepolymer is as follows: Mix 0.5 - 2 mol of aromatic diamine compound, 0.5 - 2 mol of 4,4 - biphenyl ether dianhydride, and 0.5 - 1 L of N,N - dimethylacetamide, stir at 300 - 500 r / min for 1 - 5 h, add 5 - 10 g of catalyst and 20 - 50 g of phenylethynyl phthalic anhydride, heat at 100 - 120 °C for 8 - 10 h, filter the precipitate while it is hot, wash with ethanol, and dry to obtain the polyimide prepolymer.

5. The heat-resistant reusable protective tape according to claim 4, characterized in that: The aromatic diamine compound is any one of 1,4 - bis(2,4 - diamino phenoxy)benzene, 1,4 - bis(4 - amino - 2 - trifluoromethyl phenoxy)benzene, and 4,4' - diaminodiphenyl sulfone.

6. The heat-resistant reusable protective tape according to claim 4, characterized in that, The catalyst is any one of zirconium acetylacetonate, nickel acetylacetonate, and iron tetroxide.

7. The heat-resistant reusable protective tape according to claim 1, characterized in that: The silane coupling agent is any one of 3 - (2,3 - epoxypropoxy)propyltrimethoxysilane, 3 - aminopropyltriethoxysilane, and 3 - glycidyletheroxypropyltrimethoxysilane.

8. The preparation method of the high-temperature resistant and reusable protective tape according to any one of claims 1-7, characterized in that, It includes the following steps: Take polyisoprene rubber, modified epoxy resin, zinc oxide, nano calcium carbonate, stearic acid, and silane coupling agent and add them to an open mill in sequence, mix at 50 - 80 °C for 10 - 30 min; add naphthenic oil and 0.3 - 0.8 g of polypropylene melted at 180 - 190 °C respectively, continue to mix at 50 - 80 °C for 3 - 8 min; perform calendering to control the thickness of the rubber layer at 130 ± 10 μm to obtain the high - temperature resistant and reusable protective tape.

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