Foam tape and preparation method thereof

Abstract

The invention provides a foam tape and a preparation method thereof, and relates to the technical field of adhesives, the foam tape comprises the following components by weight: 50-80 parts of a propylene pressure-sensitive adhesive, 10-20 parts of a foaming agent, 1-5 parts of a cross-linking agent, 0.5-2 parts of an antioxidant, 5-15 parts of a diluent, 1-10 parts of hydroxyapatite nanoparticles, 5-15 parts of bio-based polyamide, and 2-8 parts of flake alumina. According to the invention, due to the addition of the hydroxyapatite nanoparticles, the wear resistance, adhesive force and biocompatibility of the adhesive tape are improved, the adhesive tape is safer and more reliable in contact with a human body, and meanwhile, the strength and durability of the adhesive tape are also enhanced. And secondly, due to the introduction of bio-based polyamide, the toughness and heat resistance of the adhesive tape are improved, meanwhile, the dependence on a traditional petrochemical-based material is reduced, and the characteristics of environmental protection and sustainable development are embodied.

Description

Technical Field

[0001] The present invention relates to the technical field of adhesives, and particularly to a foam tape and a preparation method thereof. Background Art

[0002] The technical field of adhesives is a science and technology that studies and develops chemical materials and processes for connecting or bonding the surfaces of different materials. This field covers a wide range of application scenarios, from ordinary glues in daily life to high-performance structural adhesives used in industrial production. Adhesives usually include natural materials (such as starch, collagen) and synthetic materials (such as acrylic acid, epoxy resin, polyurethane, etc.), providing adhesion through physical or chemical means.

[0003] However, existing foam tapes have deficiencies in terms of abrasion resistance and adhesion. In a frequently friction environment, the bonding effect is likely to decline, affecting the stability of long-term use. At the same time, they lack thermal conductivity and cannot meet the applications of electronic devices or heat dissipation requirements, resulting in the foam tape being prone to failure or performance degradation under high-temperature conditions. In addition, the tear resistance of existing foam tapes is relatively poor, and fractures are likely to occur under high mechanical stress or extreme environments, thus affecting the bonding effect and overall durability. Summary of the Invention

[0004] The purpose of the present invention is to solve the drawbacks existing in the prior art, and a foam tape is proposed. The foam tape includes the following components by weight: 50 - 80 parts of acrylic pressure-sensitive adhesive, 10 - 20 parts of foaming agent, 1 - 5 parts of cross-linking agent, 0.5 - 2 parts of antioxidant, 5 - 15 parts of diluent, 1 - 10 parts of hydroxyapatite nanoparticles, 5 - 15 parts of bio-based polyamide, and 2 - 8 parts of flaky alumina.

[0005] Preferably, the foaming agent is azodicarbonamide or ammonium bicarbonate, the cross-linking agent is isocyanate, glyoxal or sodium hexametaphosphate, the antioxidant is 2,6 - di-tert-butyl-p-cresol or antioxidant 5057, and the diluent is toluene, ethyl acetate or n-propanol.

[0006] The present invention provides a preparation method of a foam tape, including the following steps: S1, component mixing; an inert gas protection is set in the reaction kettle, and the jacket temperature is controlled in the range of 45 - 60 °C. The adjustable-speed stirring device operates in the range of 230 - 500 RPM. The acrylic pressure-sensitive adhesive, foaming agent, cross-linking agent, antioxidant and diluent are put in, and constant stirring is maintained for 30 - 60 min. During the constant stirring period, hydroxyapatite nanoparticles are gradually added, the dispersion uniformity is monitored, and at the same time, bio-based polyamide and flaky alumina are added, and then the stirring duration is maintained for 30 - 50 min to obtain a mixture; S2, UV-assisted curing: Add a photoinitiator to the mixture and operate a magnetic stirrer at 100 - 200 RPM for 15 - 30 min to evenly distribute the photoinitiator. Then, place it in a curing chamber with UV-A, UV-B, and UV-C band output functions. Move it at a speed of 2 - 5 m / min using an automatic conveyor belt, control the irradiation time within the range of 60 - 120 s, observe the cross-linking state of the surface colloid, extend the UV-C section treatment time to 10 - 20 s in the middle section and monitor viscoelastic parameters. After the light irradiation ends, let the sample cool at ambient temperature to obtain a UV-cured product; S3, Microwave-assisted crosslinking: Apply microwave-assisted treatment to the UV-cured product and complete crosslinking in a microwave device. Select a frequency band of 2.45 GHz or 5.8 GHz as the radiation source, adjust the microwave power to the range of 800 - 1500 W, set the conveyor belt speed at 1 - 3 m / min, continuously process in the microwave cavity for 60 - 120 s, maintain the temperature monitoring point within the range of 60 - 90 °C, introduce an inert gas flow to avoid oxidation side reactions, and unload the material after stopping the microwave radiation to obtain a microwave-assisted crosslinked product.

[0007] Preferably, it further includes: S4, Foaming and crosslinking reaction: Conduct the foaming and crosslinking reaction stage in the microwave-assisted crosslinked product and raise the internal temperature to the range of 100 - 150 °C. Use a closed stirrer with an inert gas environment, set the stirring speed in the range of 100 - 300 RPM, continuously observe the change of the bubble generation rate and viscosity over time, and avoid the collapse of the cell structure with the help of real-time temperature monitoring. Maintain the stirring state for 20 - 40 min to fully decompose the foaming agent and make it cooperate with the crosslinking agent. When the internal cell distribution is uniform and the material has a microporous appearance, cut off the heating source and cool it through a water-cooled coil to obtain a uniform foaming system; S5, Plasma surface modification: Place the uniform foaming system in a low-temperature oxygen plasma device with the aim of modifying the surface and deep structure of the foam tape. Control the radio frequency power in the range of 50 - 200 W, maintain the working pressure in the range of 10 - 50 Pa, supply oxygen with a flow rate of 5 - 15 sccm, rely on a rotating mechanism to flip the foam tape in the plasma region, and control the treatment time within 1 - 3 min. By adjusting the distance between the electrode plates to be between 10 - 20 mm, make the electric field distribution concentrated. After the treatment, place it in a vacuum drying oven and cool it to room temperature to obtain the foam tape.

[0008] Preferably, in step S2, the proportion of the photoinitiator is controlled between 1 - 3 wt%.

[0009] Preferably, in step S2, the total irradiation intensity of the curing chamber is between 50 - 120 mW / cm².

[0010] Preferably, in step S4, the temperature of the water-cooled coil for cooling is 70-90°C.

[0011] 1. Compared with the prior art, in the present invention, the addition of hydroxyapatite nanoparticles improves the wear resistance, adhesion and biocompatibility of the tape, making it safer and more reliable to come into contact with the human body. At the same time, it also enhances the strength and durability of the tape. Secondly, the introduction of bio-based polyamide improves the toughness and heat resistance of the tape, while reducing the dependence on traditional petrochemical-based materials, reflecting the characteristics of environmental protection and sustainable development. In addition, the addition of flaky alumina improves the thermal conductivity of the tape, enabling it to provide excellent thermal management effects in special application scenarios such as electronics and heat dissipation, and its flaky structure further improves the tear resistance of the material. The optimization of the overall formula not only improves the performance of the tape in terms of mechanical properties, thermal properties and durability, but also expands its application fields, especially having application advantages in scenarios with high added value and high environmental protection requirements.

[0012] 2. Compared with the prior art, the present invention realizes the improvement of the performance of the bonding material by controlling the reaction conditions and the combination of materials. Especially by introducing inert gas protection and precisely controlling the temperature and stirring speed in the component mixing stage, the stability of the reaction environment is effectively maintained, and the uniformity of the materials is optimized. This strictly controlled operating environment not only ensures the smooth progress of the chemical reaction, but also avoids possible side reactions, thus ensuring the high quality of the final product. The application of ultraviolet light-assisted curing and microwave-assisted crosslinking enhances the structural integrity of the material, and through this multi-stage curing process, the bonding strength and durability of the tape are improved. In addition, the adoption of plasma surface modification technology further optimizes the surface properties of the foam tape and improves its use effect in complex environments.

[0013] The technical solutions of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0015] Figure 1 It is a preparation step diagram of a preparation method of a foam tape proposed by the present invention. Detailed Embodiments

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0017] Embodiment 1: A foam tape, the foam tape comprises the following components in parts by weight: 50 parts of propylene pressure-sensitive adhesive, 20 parts of foaming agent, 5 parts of cross-linking agent, 0.5 part of antioxidant, 15 parts of diluent, 1 part of hydroxyapatite nanoparticles, 15 parts of bio-based polyamide, and 6 parts of flaky alumina; wherein the bio-based polyamide is PA66.

[0018] In this embodiment, the foaming agent is azodicarbonamide or ammonium bicarbonate, the cross-linking agent is isocyanate, the antioxidant is 2,6-di-tert-butyl-p-cresol, and the diluent is toluene.

[0019] The present invention provides a preparation method of a foam tape, comprising the following steps: S1, component mixing; an inert gas protection is provided in the reaction kettle, and the jacket temperature is controlled at 60°C, and it is operated in the range of 500 RPM by an adjustable-speed stirring device. The propylene pressure-sensitive adhesive, foaming agent, cross-linking agent, antioxidant and diluent are added, and constant stirring is maintained for 60 min. During the constant stirring period, the hydroxyapatite nanoparticles are gradually added, the dispersion uniformity is monitored, and the bio-based polyamide and flaky alumina are added at the same time, and then the stirring duration is maintained for 50 min to obtain a mixture; S2, ultraviolet light-assisted curing; a photoinitiator is added to the mixture, and it is operated in the range of 100 RPM by a magnetic stirrer for 15 min to make the photoinitiator evenly distributed. Then it enters a curing box with UV-A, UV-B and UV-C band output functions, and is moved at a speed of 2 m / min by an automatic conveyor belt. The irradiation time is controlled in the range of 60 s, the cross-linking state of the surface colloid is observed, the treatment time of the UV-C section is extended to 10 s in the middle section and the viscoelastic parameters are monitored. After the light irradiation is over, the sample is cooled at the ambient temperature to obtain an ultraviolet-cured product; S3, microwave-assisted cross-linking; microwave-assisted treatment is applied to the ultraviolet-cured product, and cross-linking is completed in a microwave device. The frequency range of 2.45 GHz or 5.8 GHz is selected as the radiation source, the microwave power is adjusted to the range of 800 W, the conveyor belt speed is set at 1 m / min, and continuous treatment is carried out in the microwave cavity for 60 s. The temperature monitoring point is maintained in the range of 60°C, and an inert gas flow is introduced to avoid oxidation side reactions. After the microwave radiation is stopped, the material is unloaded to obtain a microwave-assisted cross-linked product; S4, Foaming and crosslinking reaction; The foaming and crosslinking reaction stage is carried out within the microwave-assisted crosslinked product, and the internal temperature is raised to the range of 100 °C. With the aid of a closed stirring in an inert gas environment, the stirring speed is set within the range of 100 RPM. Continuously observe the change of the bubble generation rate and viscosity over time. With the help of real-time temperature monitoring, avoid the collapse of the cell structure, maintain the stirring state for 20 min, so that the blowing agent decomposes fully and reacts with the crosslinking agent. When the internal cell distribution is uniform and the material shows a microporous appearance, cut off the heating source and cool down through the water-cooled coil to obtain a uniform foaming system; S5, Plasma surface modification; Place the uniform foaming system in a low-temperature oxygen plasma equipment. The goal is to modify the surface and deep structures of the foam tape. The radio frequency power is controlled within the range of 50 W, the working pressure is maintained within the range of 10 Pa, and the oxygen is supplied at a flow rate of 5 sccm. Rely on the rotating mechanism to turn the foam tape within the plasma region, and control the treatment time to 1 min. By adjusting the distance between the electrode plates to be between 10 mm, make the electric field distribution concentrated. After the treatment, place it in a vacuum drying oven and cool it to room temperature to obtain the foam tape.

[0020] In this embodiment, in step S2, the proportion of the photoinitiator is controlled at 1 wt%.

[0021] In this embodiment, in step S2, the total irradiation intensity of the curing box is 50 mW / cm².

[0022] In this embodiment, in step S1, the temperature of the water-cooled coil cooling is 70 °C.

[0023] Example 2, different from Example 1, the foam tape includes the following components by weight: 55 parts of acrylic pressure-sensitive adhesive, 20 parts of blowing agent, 5 parts of crosslinking agent, 2 parts of antioxidant, 15 parts of diluent, 10 parts of hydroxyapatite nanoparticles, 15 parts of bio-based polyamide, and 8 parts of flaky alumina.

[0024] Experimental method: Peeling Strength Test Method: This test is mainly based on standards such as GB / T 2792 or ASTM D3330, and is used to measure the bonding strength between the foam tape and the substrate at a certain peeling speed. First, take a foam tape specimen with a width of 25 mm and a length of 150 mm, and paste it on a clean and oil-free standard steel plate or a specified material plate. When attaching, use a standard roller (common mass 2 kg or 4.5 lb) to roll back and forth evenly at a speed of about 10 cm per second to expel the air behind the tape and ensure firm adhesion. Then, place the attached specimen at room temperature (23 ± 2 °C) and relative humidity 50 ± 5% for at least 24 hours to stabilize the adhesion state between the tape and the substrate. At the start of the test, fix one end of the specimen to the test fixture and leave a free end of about 50 mm for peeling operation on the tensile testing machine. Use a tensile testing machine or a special peeling strength tester, set the peeling rate generally at 300 mm / min or a specified rate (such as 100 mm / min, 150 mm / min, etc., which needs to be based on the applicable standard), and keep the peeling angle at 180°. After starting the test, record the instantaneous peeling force within a certain length range (such as a peeling distance of 50 mm to 100 mm), and calculate its average value or stable value through the data acquisition system. If large-scale fractures, uneven peeling of the adhesive layer, etc. occur during the peeling process of the material, they should be recorded and invalid data excluded or the test repeated. After the determination is completed, record the results in the form of N / cm or gf / 25 mm; if necessary, repeat the test 3 - 5 times on multiple batches of specimens, take the average value and calculate the standard deviation to evaluate the consistency between batches of the foam tape. If environmental adaptability needs to be considered, peeling strength comparative tests can also be carried out under different temperatures (such as high temperature 60 °C or low temperature -20 °C) and different humidity conditions to more comprehensively evaluate the bonding reliability of the foam tape under actual working conditions.

[0025] Initial adhesion test method: The initial adhesion is commonly measured by the "rolling ball method" or the "inclined plane method" to evaluate the instantaneous adhesion ability of the tape to the adherend after short-term contact. Here, the common rolling ball method is taken as an example: Before the test, prepare a piece of foam tape (about 300 mm in length) and fix it on a flat metal plate that can be tilted and adjusted, with the adhesive surface facing up. The adjustable angle of the inclined plate is generally 30° or other specified angles. Select a set of stainless steel balls or chrome-plated steel balls with different diameters (usually from 1 / 32 inch to 1 inch), and ensure that the surface of the balls is clean and free of oil. During the test, roll a steel ball of a certain specification along the surface of the inclined plate naturally and observe its stopping point or rolling distance on the tape. Evaluate the initial adhesion grade according to the ball number (diameter of the steel ball) and the staying state. The larger the ball number and the shorter the rolling distance it can stay within, the stronger the instantaneous adhesion performance of the tape. To ensure data accuracy, each specification of steel ball is generally tested more than 3 times and the results are recorded; if the initial adhesion of the tape is too high, the steel ball may not be able to roll or adhere instantaneously as soon as it comes into contact, and this must be noted in the test report. Similarly, if the inclined plane method is used, first stick the tape on the inclined plane substrate, and then let the test block slide down within a unit time, and measure the sliding distance or whether adhesion stops, etc. In addition, during the test process, the temperature and humidity conditions can be appropriately changed to observe the change of the initial adhesion under different environments; or the surface roughness of the substrate can be changed to simulate the real application scenario. Finally, by comparing the results of different ball numbers or different test methods, comprehensively measure the rapid adhesion ability of the foam tape under short-term contact conditions, and thus determine whether the initial adhesion meets the production and application requirements.

[0026] Adhesive Holding Power Test Method: The test for adhesive holding power (also known as shear retention or anti-slip performance) usually refers to standards such as GB / T4851 or PSTC-7, and is used to evaluate the length of time that a tape resists shear slip under a certain load, thereby reflecting the cohesion of the adhesive layer and the long-term adhesion stability. First, clean and dry the stainless steel plate or specified substrate for testing with a solvent such as isopropyl alcohol. Take a foam tape specimen with a width of 25 mm and a length of about 200 mm, and use a standard roller (2 kg or 4.5 lb) to roll back and forth once at a speed of about 10 cm per second to make the tape fully adhere to the substrate. Then, attach a reinforcing tape for hanging weights to the free end of the tape, generally with a length not exceeding 50 mm, and ensure that the adhesion is tight without bubbles. After the sample is left standing in a standard environment (temperature 23 ± 2 °C, relative humidity 50 ± 5%) for 20 - 24 hours, hang a weight of a set mass (such as 1 kg or 500 g, adjusted according to the tape thickness, viscosity, and standard requirements) at the free end. At this time, hang the sample vertically on a fixed bracket and start recording the time when the tape is pulled down by the weight and slips. If the tape shows obvious sliding or complete detachment during the test, record the moment immediately and stop timing. Usually, the data is characterized by the adhesive holding time (hours or minutes), or it can also be judged according to the time point corresponding to the sliding distance (such as 1 mm or 10 mm). To further explore the heat-resistant shear force, the same operation can be carried out at a higher temperature (such as 40 °C, 60 °C, etc.) or in a high-humidity environment. If the tape can still maintain long-term stability without slipping, it indicates that it has good thermal stability and adhesive holding ability. After the test, statistically analyze and compare the obtained time results to judge the comprehensive adhesive holding performance of foam tapes prepared with different formulations, different thicknesses, or different processes. If it is necessary to study the influence brought by the difference in crosslinking degree, this test can also be repeated on samples at different time periods to compare the correlation between the crosslinking degree and the adhesive holding power.

[0027] Compression Rebound Rate Test Method: The compression rebound rate is an important indicator to measure the ability of the foam tape to recover from deformation after being subjected to compressive stress, and is used to characterize the elasticity and support of the internal pore structure of the foam material. Before the test, several rectangular or circular foam tape specimens are cut, ensuring that their thickness and dimensions are consistent (for example, with a diameter of 25 mm and a thickness of the normal use thickness of the tape). The specimens are placed in a thermostatic and humidistatic chamber and equilibrated for at least 24 hours under standard environmental conditions (23 ± 2 °C, RH 50 ± 5%) to ensure that the effects of humidity and temperature are controllable. During the test, a special fixture equipped with a compression performance tester or a tensile machine is used to keep the specimen at a specified compression amount (such as 25%, 50%, or 75% of the initial thickness) for a certain period of time (such as 30 minutes or 1 hour), and then the load is released, and the thickness of the specimen after a specific recovery time (such as 30 seconds, 60 seconds, or 5 minutes) is recorded. The general calculation formula is: Compression Rebound Rate (%) = [(Thickness after recovery - Thickness measured immediately after compression) / (Original thickness - Thickness measured immediately after compression)] × 100%, or the definition of relevant industry standards is adopted. If international standards such as DIN 53572 are used, the detailed requirements may vary slightly, but the core idea is the same: by monitoring the rebound height of the material after being compressed, its elastic retention ability is evaluated. For foam tapes, the same compression-rebound test can also be carried out under different temperature conditions (such as -20 °C, 25 °C, 60 °C) to observe the changes in its mechanical properties in low-temperature or high-temperature environments. If permanent deformation or collapse of the internal cell structure occurs in the specimen during the recovery process, the compression rebound rate will decrease significantly. By comparing specimens with different formulations, different foaming processes, and different crosslinking degrees, their comprehensive compression and rebound characteristics can be obtained, providing a basis for the practical application of foam tapes (such as shock absorption, buffering, sealing, etc.).

[0028] Aging resistance performance test method: Aging resistance test is used to evaluate the degree of performance attenuation of the foam tape under the long-term action of external environmental factors (such as light, temperature, humidity, oxidizing gas, etc.). The specific operation can refer to the accelerated aging test in standards such as GB / T 16422.2 or ASTM G154, or a comprehensive evaluation can be carried out relying on ultraviolet aging chambers, high and low temperature cycling chambers, and damp heat aging equipment. Taking ultraviolet aging as an example: Cut the prepared foam tape into appropriate sizes, stick it on a strong and corrosion-resistant test plate, and keep the surface clean and pollution-free. When placing it in the ultraviolet aging chamber, it should be ensured that the sample surface faces the ultraviolet lamp tube. The lamp tubes commonly use UVA or UVB bands (such as 340nm, 313nm), and at a certain irradiation intensity (for example, 0.76W / m² or refer to the corresponding standard). According to the set program, ultraviolet irradiation and condensation or spraying can be cycled alternately to simulate outdoor rain, sunlight, etc. The test cycle can be as long as hundreds of hours to thousands of hours (such as 500h, 1000h, 2000h), and samples are taken out at regular intervals (such as every 100h or 200h) to measure key indicators such as their appearance, color, adhesion performance, peel strength, etc., and record whether phenomena such as cracks, powdering, and cell collapse occur. For high and low temperature aging, the cycle conditions of -20°C to 80°C can be set, and each temperature section is maintained for several hours or several days, and repeated several times; damp heat aging is tested in a high temperature and high humidity environment such as 85°C, 85%RH for a certain period of time (such as 100h, 240h). Finally, by comparing the change rates of its mechanical properties, appearance morphology, and adhesion indicators, the service life of the foam tape in various extreme or harsh environments can be judged. This method can intuitively reflect the comprehensive influence of the foaming process, crosslinking degree, and surface modification on the durability of the material, and has important reference value for applications in outdoor, automotive parts, or electronic device environments.

[0029] The finished materials prepared in Examples 1-2 were experimented. Among them, Comparative Example 1 was a foam strong adhesive EVA foam double-sided tape of the Huanguan brand with the product number 0.0.8. The experimental results are as follows: Table 1 Performance test data Performance Index Comparative Example 1 Example 1 Example 2 Peeling Strength (N / cm) 10.2 13.5 14.6 Initial Adhesion (Ball Number) 8 12 13 Holding Adhesion (h) 24 48 50 Compression Rebound Rate (%) 60 75 78 Aging Resistance Performance (Excellent - Poor) Medium Excellent Excellent As can be seen from Table 1, the foam tapes prepared in Examples 1-2 generally perform better than the sample of Comparative Example 1 in all indicators. Especially in the long-term use environment, they can maintain stable adhesion performance and elastic recovery ability, and still show strong anti-attenuation characteristics under accelerated aging conditions. These advantages mean that the present invention can provide a more reliable bonding effect, better durability, and more comprehensive environmental adaptability in practical applications.

Claims

1. A foam tape, characterized in that, The foam tape comprises the following components in parts by weight: 50 - 80 parts of propylene pressure-sensitive adhesive, 10 - 20 parts of foaming agent, 1 - 5 parts of cross-linking agent, 0.5 - 2 parts of antioxidant, 5 - 15 parts of diluent, 1 - 10 parts of hydroxyapatite nanoparticles, 5 - 15 parts of bio-based polyamide, and 2 - 8 parts of flaky alumina.

2. The foam tape according to claim 1, wherein: The foaming agent is azodicarbonamide or ammonium bicarbonate, the cross-linking agent is isocyanate, glyoxal or sodium hexametaphosphate, the antioxidant is 2,6-di-tert-butyl-p-cresol or antioxidant 5057, and the diluent is toluene, ethyl acetate or n-propanol.

3. A method for preparing the foam tape according to claim 1 or 2, characterized in that, It includes the following steps: S1, Component mixing; An inert gas protection is set inside the reaction kettle, and the jacket temperature is controlled in the range of 45 - 60 °C. The adjustable-speed stirring device operates in the range of 230 - 500 RPM. The propylene pressure-sensitive adhesive, foaming agent, cross-linking agent, antioxidant and diluent are added, and constant stirring is maintained for 30 - 60 min. During the constant stirring, hydroxyapatite nanoparticles are gradually added, the dispersion uniformity is monitored, and at the same time, bio-based polyamide and flaky alumina are added, and then the stirring duration is maintained for 30 - 50 min to obtain a mixture. S2, UV-assisted curing; A photoinitiator is added to the mixture, and the magnetic stirrer operates in the range of 100 - 200 RPM for 15 - 30 min to make the photoinitiator evenly distributed. Then it enters a curing box with UV-A, UV-B and UV-C band output functions. The automatic conveyor belt moves at a speed of 2 - 5 m / min, the irradiation time is controlled in the range of 60 - 120 s, the cross-linking state of the surface colloid is observed, the treatment time of the UV-C section is extended to 10 - 20 s in the middle section and the viscoelastic parameters are monitored. After the light irradiation ends, the sample is cooled at the ambient temperature to obtain a UV-cured product. S3, Microwave-assisted cross-linking; The UV-cured product is subjected to microwave-assisted treatment and cross-linking is completed in a microwave device. The frequency section of 2.45 GHz or 5.8 GHz is selected as the radiation source, the microwave power is adjusted to the range of 800 - 1500 W, the conveyor belt speed is set at 1 - 3 m / min, the continuous treatment in the microwave cavity is 60 - 120 s, the temperature monitoring point is maintained in the range of 60 - 90 °C, and an inert gas flow is connected to avoid oxidation side reactions. After stopping the microwave radiation, the material is unloaded to obtain a microwave-assisted cross-linked product.

4. The preparation method of the foam tape according to claim 3, characterized in that, It also includes: S4, Foaming and cross-linking reaction; A foaming and cross-linking reaction stage is carried out in the microwave-assisted cross-linked product, and the internal temperature is raised to the range of 100 - 150 °C. Using a closed stirring with an inert gas environment, the stirring speed is set in the range of 100 - 300 RPM. The generation rate of bubbles and the change of viscosity with time are continuously observed. With the help of real-time temperature monitoring, the collapse of the cell structure is avoided, and the stirring state is maintained for 20 - 40 min to make the foaming agent fully decompose and cooperate with the cross-linking agent. When the internal cell distribution is uniform and the material has a microporous appearance, the heating source is cut off and cooled through a water-cooled coil to obtain a uniform foaming system. S5. Plasma surface modification: Place the uniform foaming system in a low-temperature oxygen plasma equipment with the aim of modifying the surface and deep structures of the foam tape. The radio frequency power is controlled in the range of 50 - 200 W, the working pressure is maintained in the interval of 10 - 50 Pa, and oxygen is supplied at a flow rate of 5 - 15 sccm. Rely on the rotating mechanism to flip the foam tape within the plasma region, and control the treatment time within 1 - 3 min. By adjusting the distance between the electrode plates to be between 10 - 20 mm, make the electric field distribution concentrated. After the treatment, place it in a vacuum drying oven and cool it to room temperature to obtain the foam tape.

5. The preparation method of the foam tape according to claim 3, characterized in that: In step S2, the proportion of the photoinitiator is controlled between 1 - 3 wt%.

6. The preparation method of the foam tape according to claim 3, wherein: In step S2, the total irradiation intensity of the curing box is between 50 - 120 mW / cm².

7. The preparation method of the foam tape according to claim 4, characterized in that: In step S4, the temperature for cooling by the water-cooled coil is 70 - 90 °C.

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