A degradable electrolytic viscose, a preparation method thereof, an electrolytic viscose film and an electrolytic viscose tape

Abstract

The application discloses degradable electrolytic viscose, a preparation method thereof, electrolytic viscose film and electrolytic viscose tape. The electrolytic viscose comprises the following components: a full-aliphatic polyester block copolymer glue base, conductive fillers, polyether polymer additives and tackifying resins, wherein the mass ratio of the components is as follows: glue base: conductive fillers = 1-20:1, glue base: tackifying resins = 1-5:1, and glue base: polyether polymer additives = 5-10:1. The application constructs a composite material of the full-aliphatic polyester block copolymer glue base + conductive fillers + polyether polymer additives, and the three components are synergistic with each other, so that the electrolytic viscose has high peeling strength and high viscous force when not electrified, can be reversibly and efficiently debonded non-destructively under low-voltage electrification, and has no surface residue, thereby avoiding damage to the bonding surface during debonding. The glue base is easy to degrade and can be completely degraded into water-dispersible substances under mild conditions, and is green and pollution-free.

Description

Technical Field

[0001] This invention relates to an adhesive material and its preparation method, an electrolytic adhesive film and an electrolytic adhesive tape, and more particularly to a biodegradable electrolytic adhesive and its preparation method, an electrolytic adhesive film and an electrolytic adhesive tape. Background Technology

[0002] Adhesive materials are widely used in key areas such as high-performance tapes, protective films, medical patches, and electronic device assembly. Their core design goal is to achieve rapid and stable adhesion. Ideally, they should be able to quickly wet and adhere to various substrate surfaces (such as metals, plastics, glass, and skin) with only slight and brief pressure, forming initial adhesion; simultaneously, they should provide reliable holding power throughout their service life, ensuring that the adhered objects do not shift or detach. However, traditional adhesives face a key challenge in practical applications: there is a contradiction between their "easy removal" design goal and the actual performance requirement of "durable adhesion." After their service life, complete peeling is difficult—the adhesive layer may remain on the substrate surface (contamination), or the adhesive strength may be too strong, causing fragile substrates (such as foam and films) to tear and break during peeling. Therefore, developing a new generation of adhesives that combines high-strength, durable adhesion with easy peeling and residue-free properties after service life is one of the important directions for sustainable development in this field.

[0003] Electrolytic adhesive technology is a reversible bonding technology based on electrochemical interface regulation. It involves applying a low-voltage DC electric field to the interface between a polymer adhesive system containing an ion-conductive medium and a substrate, triggering interfacial ion migration, polarization, or localized electrolytic reactions to achieve controllable switching of adhesive strength. Examples include an electro-peelable adhesive composition and its application disclosed in CN117795031A; an electrolytic adhesive, electrolytic cotton tape, and its preparation method disclosed in CN121495492A; and an electrolytic adhesive, its preparation method, and electrolytic adhesive tape disclosed in CN120025765A. However, these electrolytic adhesives all primarily consist of a cross-linked polyacrylic acid adhesive layer. The carbon-carbon bonds in the adhesive molecular skeleton have high chemical bond energies, making them difficult to break under mild conditions. This hinders rapid degradation after the tape's service life, requiring further improvement in environmental friendliness. Furthermore, their limited adhesion limits their application to fixing critical components with stringent peel strength requirements. Summary of the Invention

[0004] Objectives of the Invention: The objective of this invention is to provide a biodegradable, reusable, low-response-voltage, residue-free electrolytic adhesive. The second objective of this invention is to provide a method for preparing the electrolytic adhesive. The third objective of this invention is to provide an electrolytic adhesive film containing the electrolytic adhesive. The fourth objective of this invention is to provide an electrolytic adhesive tape containing the electrolytic adhesive.

[0005] Technical solution: The biodegradable electrolytic adhesive of the present invention comprises the following components: aliphatic polyester block copolymer adhesive matrix, conductive filler, polyether polymer additive, and tackifying resin, wherein the mass ratio of each component is: adhesive matrix: conductive filler = 1-20:1, adhesive matrix: tackifying resin = 1-5:1, and adhesive matrix: polyether polymer additive = 5-10:1.

[0006] The aliphatic polyester block copolymer adhesive matrix is ​​composed of hard segments and soft segments, with the hard segments accounting for 10-30% of the mass of the soft segments. Soft segments refer to amorphous polymers, such as polycaprolactone with side chains; hard segments refer to semi-crystalline polymers, such as poly(L-lactic acid) and poly(D-lactic acid). The hard segments, through microphase separation and physical cross-linking, enhance the cohesive strength of the adhesive, maintaining its integrity during peeling, thereby improving the adhesion, tensile strength, and peel strength of the electrolytic adhesive. The soft segments improve the flow properties of the adhesive matrix, imparting excellent interfacial wettability to the adhesive, thus increasing the viscosity of the electrolytic adhesive and making it easy to coat, suitable for bonding surfaces with different morphologies. By chemically bonding the immiscible hard and soft segments to form a block copolymer structure and controlling the mass ratio of hard to soft segments in the adhesive matrix, the subsequently prepared electrolytic adhesive achieves a balance of strong adhesion, high peel strength, and good viscosity, resulting in long-lasting adhesion. When the content of hard segments is too high, although the cohesive force of the adhesive matrix is ​​enhanced, the interfacial wettability decreases, resulting in a decrease in peel strength. When the content of soft segments is too high, although the interfacial wettability of the adhesive matrix is ​​enhanced, the cohesive strength decreases, resulting in poor adhesion, tensile properties and peel strength.

[0007] The hard segment is polylactic acid, preferably polylactic acid synthesized from L-lactide; the soft segment is one of poly(4-methyl-ε-caprolactone), poly(ε-decanoic acid), and poly(β-methyl-δ-valerolactone). The carbon-oxygen ester bond energy in the fully aliphatic polyester block copolymer is low, allowing it to completely degrade into a water-dispersible substance under mild conditions, resulting in high environmental friendliness. Furthermore, it possesses high cohesive strength and good interfacial wettability, giving the adhesive matrix high peel strength.

[0008] The all-aliphatic polyester block copolymer adhesive matrix is ​​at least one of polylactic acid-poly(4-methyl-ε-caprolactone) block copolymer, polylactic acid-poly(ε-decanoic acid) block copolymer, and polylactic acid-poly(β-methyl-δ-valerolactone) block copolymer.

[0009] The conductive filler is at least one of 1-ethyl-3-methylimidazolium sulfate, 1-methylimidazolium, N-ethylpyridine bromide, gallium metal, 1-decyl-3-methylimidazolium chloride, and poly(3-hexylthiophene). The conductive filler is rich in electrons, requiring only a low response voltage to undergo electro-migration and phase separation. It accumulates and enriches on the electrolytic adhesive and bonding surface, forming a weak boundary layer with low adhesion energy. This reduces the interfacial energy and interfacial tension in the local area, thereby reducing interfacial adhesion and achieving residue-free, efficient peeling of the adhesive through electro-responsive bonding. Furthermore, the electro-migration process relies on physical migration and changes in interfacial properties, without involving irreversible electrochemical decomposition, thus avoiding damage to the bonding surface. After the applied voltage is stopped, the electrolytic adhesive can be reused, resulting in a long service life.

[0010] The polyether-based polymeric additive is at least one selected from polyethylene glycol, polypropylene glycol, polytetrahydrofuran, and polyethylene glycol-polyethylene block copolymer. This polyether-based polymeric additive has high polarity and a structure similar to the aforementioned adhesive matrix. It can increase the interfacial wettability of the electrolytic adhesive, ensure sufficient dispersion of conductive fillers in the adhesive matrix, promote ion migration, regulate the electroinduced migration rate of conductive fillers, accelerate the accumulation and enrichment of conductive fillers at the interface, and reduce the voltage and time required to trigger electrolytic bonding. There is no limitation on the molecular weight of the polyether-based polymeric additive; those skilled in the art can adjust it within a conventional range according to the specific type selected. Considering both the dispersibility of conductive fillers and the solubilization of the adhesive matrix, a molecular weight of 1000~9000 g / mol is preferred.

[0011] The tackifying resin is at least one of hydrogenated rosin resin, rosin resin, terpene resin, and C9 petroleum resin, and is used to further adjust the viscosity of the electrolytic adhesive.

[0012] The method for preparing the biodegradable electrolytic adhesive of the present invention includes the following steps: dispersing the all-aliphatic polyester block copolymer adhesive matrix with an organic solvent, and then adding tackifying resin, polyether polymer additives and conductive fillers according to the corresponding mass ratios. Each time a component is added, the mixture is stirred to ensure that it is fully dispersed, thereby obtaining a uniform adhesive solution.

[0013] Preferably, the organic solvent is ethyl acetate (EA), and the stirring is performed at 200 rpm for 15 minutes at room temperature.

[0014] The electrolytic adhesive film of the present invention is prepared from the aforementioned biodegradable electrolytic adhesive, the preparation of which includes coating the biodegradable electrolytic adhesive onto the surface of a substrate to form an adhesive film.

[0015] The electrolytic adhesive tape of the present invention includes the aforementioned biodegradable electrolytic adhesive or the aforementioned electrolytic adhesive film.

[0016] The electrolytic adhesive tape further includes a substrate layer and a release film layer. The substrate layer is one of aluminum foil, copper foil or polyimide film, and the release film layer is polyethylene terephthalate (PET).

[0017] The electrolytic adhesive tape is prepared by the following steps: applying electrolytic adhesive to the surface of a polished and cleaned substrate layer to form an adhesive film, covering the adhesive film with a release film layer, rolling it to make it bond tightly, and drying it to obtain the electrolytic adhesive tape.

[0018] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) It constructs a composite material of aliphatic polyester block copolymer glue matrix + conductive filler + polyether polymer additive. The three components work synergistically with each other. The conductive filler and polyether polymer additive can dilute the chain entanglement of molecular chains in the soft segments of the aliphatic polyester block copolymer, so that the glue can fully wet the substrate surface. It significantly improves the interfacial wettability without destroying the cohesive strength, so that it has high peel strength and high adhesion when no electricity is applied. When electricity is applied under low voltage, it can non-destructively and reversibly de-adhere efficiently, and there is no residue on the substrate surface, avoiding damage to the bonding surface during de-adhesion; (2) The aliphatic polyester block copolymer The adhesive matrix is ​​easy to degrade and can be completely degraded into water-dispersible substances under mild conditions without leaving any adhesive residue. Conductive fillers, polyether polymer additives and tackifying resins can be completely dissolved or dispersed in water, leaving no residue on the tape base film, significantly improving the environmentally friendly performance of electrolytic adhesives, making them green and pollution-free; (3) Electrolytic adhesive tapes can be reused, which is beneficial for the repair, recycling and reuse of the bonded parts, significantly expanding the application range and scenarios of adhesives; (4) The preparation method is simple and easy to implement, convenient to operate, and has little dependence on special equipment. It does not require complex synthesis steps or precise operations. It can be adapted to large-scale industrial production processes using conventional mixing and coating equipment, and has high promotion and application value. Attached Figure Description

[0019] Figure 1 The residual adhesive layer of the electrolytic adhesive prepared in Example 1 of this invention was tested on a stainless steel surface before and after energizing. Detailed Implementation

[0020] The technical solution of the present invention will be further described below with reference to the embodiments and comparative examples. Unless otherwise stated, all reagents used are commercially available and are used directly without purification.

[0021] Example 1

[0022] At room temperature, the adhesive matrix is ​​added to a reaction vessel, and ethyl acetate solvent is added at a mass ratio of 1:1 (adhesive matrix to ethyl acetate). The mixture is stirred at 200 rpm for 15 min to mix. Tackifying resin is added at a mass ratio of 3:1 (adhesive matrix to tackifying resin), and stirred for 15 min to mix. Polyether polymer is added at a mass ratio of 10:1 (adhesive matrix to polyether polymer), and stirred for 15 min to mix. Conductive filler is added at a mass ratio of 1:10 (conductive filler to adhesive matrix), and stirred for 15 min to mix, resulting in a homogeneous adhesive solution, which is a biodegradable electrolytic adhesive. The adhesive matrix is ​​polylactic acid-poly(4-methyl-ε-caprolactone) block copolymer, the tackifying resin is rosin resin, the polyether polymer is polyethylene glycol, and the conductive filler is 1-decyl-3-methylimidazolium chloride.

[0023] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an electrolytic adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in an electrolytic adhesive tape.

[0024] Ten 1cm × 1cm pieces of electrolytic adhesive tape were cut and their peel strength was tested under different applied voltages and energizing times. The test results are shown in Table 1. The specific test methods are as follows:

[0025] The electrolytic adhesive tape bonded to the stainless steel plate was energized (voltage 0~15V), and the peel strength of the electrolytic adhesive tape after energization was tested according to GB / T2792-2014 standard. The surface of the stainless steel plate was also observed for any residual adhesive, and the energizing time and voltage were recorded.

[0026] Table 1. Peel strength test results of electrolytic adhesive tape after energization 1 0 0 73 Completely Residual 2 5 0.5 7±2 More residue 3 5 1 5±1 Blocky residue 4 5 1.5 2±1 Small amount of spot-like residue 5 10 0.5 5±2 Blocky residue 6 10 1 4±1 Small amount of spot-like residue 7 10 1.5 1±0.5 No residue 8 15 0.5 3±2 Small amount of spot-like residue 9 15 1 2±1 No residue 10 15 1.5 1±0.5 No residue

[0027] Among them, photographs were taken to record the electrolytic adhesive tape prepared in Example 1 before it was energized (see attached image). Figure 1 (a) in the table corresponds to serial number 1 in Table 1 and the result after power-on (see appendix). Figure 1 (b) corresponds to item 10) in Table 1) the residual adhesive layer on the stainless steel surface after the peel test. The results are shown in the attached diagram of the instruction manual. Figure 1 As shown in (a), after peeling without applying electricity, the white adhesive film on the surface of the stainless steel plate remained completely; (attached) Figure 1 As shown in (b), after electrolytic peeling, there was no white adhesive residue on the surface of the stainless steel plate.

[0028] Depend on Figure 1As shown in Table 1, the electrolytic adhesive tape prepared in Example 1 exhibits high initial peel strength when no electricity is applied, forming a rapid and effective interface anchor to the substrate after bonding. However, under lower applied voltage (5V) and shorter energizing time (0.5min), the peel strength decreases significantly by 87.6% (item 2), and debonding begins. When the energizing time increases to 1.5min, the peel strength decreases by 95.7%, and most of the tape debonds, leaving only a few dotted residues on the substrate surface (item 4). At a response voltage of 10V, after 1.5min of energizing, the peel strength decreases by 98%, the tape completely debonds, and there is no residue on the substrate surface (item 7). At a response voltage of 1.5V, the tape completely debonds after only 1min of energizing, leaving no residue on the substrate surface; at this point, the peel strength decreases by 95.7% (item 9). Therefore, the electrolytic adhesive prepared by the present invention has high peel strength and high adhesion when no electricity is applied, and can quickly and efficiently de-adhere after being energized at low voltage, leaving no residue on the substrate surface and avoiding damage to the substrate surface caused by high voltage.

[0029] After repeated use, the electrolytic adhesive tape underwent a peel strength test after being energized. The test results are shown in Table 2. The specific test method is as follows:

[0030] After being electrolyzed and peeled off, the electrolytic adhesive tape (15 V voltage, 1 min energizing time) was reattached to the stainless steel plate. Energization was then applied (15 V voltage, 1 min energizing time), and the test was performed according to GB / T2792-2014 standard. This process was repeated 9 times, and the peel strength of the electrolytic adhesive tape after energization was measured within each of the 9 repeated tests. Any residual adhesive on the stainless steel plate surface was also observed. In the 10th re-attachment to the stainless steel plate, the peel strength of the tape without energization was measured according to GB / T2792-2014 standard, and any residual adhesive on the stainless steel plate surface was observed again.

[0031] Table 2. Peel strength test results of the adhesive tape after 9 repeated experiments with and without energization in the 10th experiment. 1 2±0.5 No residue 2 4±1 No residue 3 3±1 No residue 4 8±3 No residue 5 6±4 No residue 6 7±1 No residue 7 10±4 Small amount of spot-like residue 8 9±5 Small amount of spot-like residue 9 8±6 Small amount of spot-like residue 10 (No power) 58±9 Completely Residual

[0032] Table 2 shows that due to the excellent compatibility of polyether and conductive filler in the adhesive matrix, and the reversible enrichment-compatibility effect of conductive filler at the interface between the stainless steel surface and the tape after energization, no adhesive residue was found on the stainless steel plate surface within 6 repeated energized peel tests. However, after 7-9 repeated energized peel tests, some conductive filler remained, lost on the stainless steel plate surface, resulting in adhesive residue. Within the number of repeated tests, the peel strength after energization was significantly lower than the initial peel strength without energization and remained stable, demonstrating good repeatability. However, the variation in peel strength decreased after repeated energization, and a small amount of dotted residue remained on the stainless steel plate surface. This was mainly due to the increased peel strength caused by the increased cohesive strength of the electrolytic adhesive resulting from the loss of some conductive filler. In the 10th repeated experiment, the non-electrolytic adhesive tape retained a peel strength and residual adhesive condition similar to the initial state before the energization. Although the peel strength was somewhat reduced after the 10th non-electrolytic peel strength due to the aforementioned residual loss, its value remained at a high level. This indicates that the electrolytic adhesive process is reversible, the energization process has a limited impact on the adhesive properties of the electrolytic adhesive tape, the tape peel composition is stable, the peel strength is well maintained, and it can be reused.

[0033] The adhesive properties of the electrolytic adhesive tape were tested, and the test results are shown in Table 3. The specific test method is as follows:

[0034] The assembly was fixed on a test platform with an inclination angle of 0° (horizontal state). After applying a voltage of 10V to the adhesive material, a standard weight (mass of 500±0.5g) was suspended at the free end of the test tape, and the time (t / s) required for the tape to be completely peeled off from the adhesive film surface was recorded.

[0035] Table 3 Adhesive Strength Properties of Electrolytic Adhesive Tape 1 0 3000+ 2 0.5 705 3 1.0 180 4 1.5 114 5 2.0 70 6 2.5 25 7 3.0 10

[0036] As shown in Table 3, the electrolytic adhesive tape prepared in Example 1 can adhere for a long time when no electricity is applied, and has excellent adhesion performance; however, it can de-adhere quickly under low voltage, which further confirms the results in Table 1.

[0037] The biodegradability of the electrolytic adhesive tape was tested, and the test results are shown in Table 4. The specific test method is as follows:

[0038] Cut 10 pieces of adhesive film, each 1 cm × 1 cm in size, and place them in separate 20 mL sample vials. Add 1 mol / L NaOH solution to each vial. At regular intervals, remove the insoluble material from the sample vials, remove any surface moisture, weigh the samples, and record the time and corresponding mass.

[0039] Table 4. Test results of the biodegradability of electrolytic adhesive tape 2 0.0326 0.0258 0.0068 0.0064 95.3 4 0.0342 0.0258 0.0084 0.008 95.2 6 0.0324 0.0258 0.0066 0.0059 89.4 10 0.0331 0.0258 0.0073 0.0065 89.0 15 0.0346 0.0258 0.0088 0.0075 80.1 20 0.0337 0.0258 0.0079 0.0055 71.4 25 0.0340 0.0258 0.0082 0.0045 54.9 30 0.0345 0.0258 0.0087 0.0036 41.4 40 0.0333 0.0258 0.0075 0.0018 24.0 55 0.0328 0.0258 0.007 0.0000 0.0

[0040] As shown in Table 4, the electrolytic adhesive tape prepared in Example 1 can be completely degraded under mild conditions without any residue. This is because the carbon-oxygen bonds in the all-aliphatic polyester block copolymer, which serves as the adhesive matrix, can be broken under mild conditions, causing it to degrade into water-dispersible substances. Furthermore, the conductive filler, polyether polymer additives, and tackifying resin used in Example 1 can be completely dissolved or dispersed in water, leaving no residue on the tape base film. This significantly improves the environmentally friendly performance of the electrolytic adhesive, making it green and pollution-free.

[0041] Example 2

[0042] At room temperature, the adhesive matrix is ​​added to a reaction vessel, and ethyl acetate solvent is added at a mass ratio of 1:1 (adhesive matrix to ethyl acetate). The mixture is stirred at 200 rpm for 15 min to mix. Tackifying resin is added at a mass ratio of 5:1 (adhesive matrix to tackifying resin), and stirred for 15 min to mix. Polyether polymer is added at a mass ratio of 10:1 (adhesive matrix to polyether polymer), and stirred for 15 min to mix. Conductive filler is added at a mass ratio of 1:10 (conductive filler to adhesive matrix), and stirred for 15 min to mix, resulting in a homogeneous adhesive solution, which is a biodegradable electrolytic adhesive. The adhesive matrix is ​​polylactic acid-poly(β-methyl-δ-valerolactone) block copolymer, the tackifying resin is C9 petroleum resin, the polyether polymer is polypropylene glycol, and the conductive filler is a mixture of gallium metal and poly(3-hexylthiophene) in equal mass ratios.

[0043] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an electrolytic adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in an electrolytic adhesive tape.

[0044] The electrolytic adhesive tape was subjected to the same peel strength test after being energized as in Example 1, and the test results are shown in Table 5.

[0045] Table 5. Peel strength test results of electrolytic adhesive tape after energization 1 0 0 84 Completely Residual 2 5 0.5 16±2 More residue 3 5 1 10±1 Blocky residue 4 5 1.5 6±1 Small amount of spot-like residue 5 10 0.5 12±2 Blocky residue 6 10 1 7±1 Small amount of spot-like residue 7 10 1.5 2±0.5 No residue 8 15 0.5 10±2 Small amount of spot-like residue 9 15 1 4±1 No residue 10 15 1.5 1±0.5 No residue

[0046] The biodegradability of the electrolytic adhesive tape was tested, and the results are shown in Table 6. The specific test method is as follows:

[0047] Cut 10 pieces of adhesive film, each 1 cm × 1 cm in size, and place them in separate 20 mL sample vials. Add 1 mol / L NaOH solution to each vial. At regular intervals, remove the insoluble material from the sample vials, remove any surface moisture, weigh the samples, and record the time and corresponding mass.

[0048] Table 6. Test results of the biodegradability of electrolytic adhesive tape 2 0.0355 0.0258 0.0097 0.0091 93.8 4 0.0394 0.0258 0.0136 0.0089 65.4 6 0.0370 0.0258 0.0112 0.0055 49.1 10 0.0338 0.0258 0.0080 0.0031 38.8 15 0.0376 0.0258 0.0118 0.0025 21.2 20 0.0359 0.0258 0.0101 0.0013 12.9 25 0.0368 0.0258 0.0110 0.0004 3.6 30 0.0392 0.0258 0.0134 0.0005 3.7 40 0.0363 0.0258 0.0105 0.0000 0.0 55 0.0352 0.0258 0.0094 0.0000 0.0

[0049] As can be seen from Table 6, although metallic gallium and poly(3-hexylthiophene) used as conductive fillers are insoluble in water, they are fully dispersed in the electrolytic adhesive in the form of small particles during the preparation process. Therefore, after the adhesive matrix is ​​completely degraded, the conductive fillers can be dispersed in water without leaving any residue.

[0050] After repeated use, the electrolytic adhesive tape underwent a peel strength test after being energized. The test results are shown in Table 7. The specific test method is as follows:

[0051] The electrolytic adhesive tape, after being peeled off under electrical current (15 V, 1 min), was reattached to the stainless steel plate and then electrified again (15 V, 1 min). The test was performed according to GB / T2792-2014 standard, repeated 9 times. The peel strength of the electrolytic adhesive tape after electrification was measured within each of the 9 repeated tests, and any residual adhesive on the stainless steel plate surface was observed. In the 10th re-attachment to the stainless steel plate, the peel strength of the tape without electrification was measured according to GB / T2792-2014 standard, and any residual adhesive on the stainless steel plate surface was observed.

[0052] Table 7. Peel strength test results of the electrolytic adhesive tape after 9 repeated experiments with and without 10 repeated experiments. 1 5±0.5 No residue 2 4±0.5 No residue 3 3.5±2 No residue 4 4±1 No residue 5 3±2 No residue 6 4±1 No residue 7 6±2 No residue 8 11±7 Small amount of spot-like residue 9 14±3 Small amount of spot-like residue 10 (No power) 69±4 Completely Residual

[0053] Example 3

[0054] At room temperature, the adhesive matrix is ​​added to a reaction vessel, and ethyl acetate solvent is added at a mass ratio of 1:1 (adhesive matrix to ethyl acetate). The mixture is stirred at 200 rpm for 15 min to mix. Tackifying resin is added at a mass ratio of 2:1 (adhesive matrix to tackifying resin), and stirred for 15 min to mix. Polyether polymer is added at a mass ratio of 10:1 (adhesive matrix to polyether polymer), and stirred for 15 min to mix. Conductive filler is added at a mass ratio of 1:20 (conductive filler to adhesive matrix), and stirred for 15 min to mix, resulting in a homogeneous adhesive solution, which is a biodegradable electrolytic adhesive. The adhesive matrix is ​​polylactic acid-poly(ε-decyl lactone) block copolymer, the tackifying resin is hydrogenated rosin resin, the polyether polymer is polyethylene glycol-polyethylene block copolymer, and the conductive filler is a mixture of ethyl 1-ethyl-3-methylimidazolium sulfate and 1-methylimidazolium in equal mass ratios.

[0055] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an electrolytic adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in an electrolytic adhesive tape.

[0056] The electrolytic adhesive tape underwent the same peel strength test after energization as in Example 1, and the results are shown in Table 8. Table 8 shows that in this example, applying a 10V voltage for 1.5 minutes resulted in easy detachment of the electrolytic adhesive, with a peel strength reduction of approximately 98%, and no adhesive residue on the stainless steel plate surface. However, due to the increased tackifying resin content in this example, the adhesive matrix was diluted, increasing the wettability of the electrolytic adhesive interface, which in turn led to a decrease in the cohesive strength of the electrolytic adhesive tape and consequently a decrease in the initial peel strength. Therefore, the tackifying resin content should not be excessive.

[0057] Table 8 Peel strength test of electrolytic adhesive tape after energization 1 0 0 48 Completely Residual 2 5 0.5 19±7 More residue 3 5 1 11±4 Blocky residue 4 5 1.5 2±1 Small amount of spot-like residue 5 10 0.5 6±2 Blocky residue 6 10 1 2±1 Small amount of spot-like residue 7 10 1.5 1±1 No residue 8 15 0.5 3±2 Small amount of spot-like residue 9 15 1 2±1 No residue 10 15 1.5 1±1 No residue

[0058] After repeated use, the electrolytic adhesive tape underwent a peel strength test after being energized. The test results are shown in Table 9. The specific test method is as follows:

[0059] The electrolytic adhesive tape, after being peeled off under electric current (15 V, 1 min), was re-attached to a stainless steel plate and electrified (15 V, 1 min). The peel strength was tested according to GB / T2792-2014 standard, repeated 9 times. The peel strength of the electrolytic adhesive tape after electrification was tested in each of the 9 repeated experiments, and any residual adhesive on the stainless steel plate surface was observed. In the 10th re-attachment, the peel strength of the tape without electrification was tested according to GB / T2792-2014 standard, and any residual adhesive on the stainless steel plate surface was observed. Notably, after the 10th re-attachment, due to the partial loss of conductive filler, the cohesive strength of the adhesive increased, resulting in improved peel strength.

[0060] Table 9. Peel strength test results of the adhesive tape after 9 repeated experiments with and without energization in the 10th experiment. 1 1±0.5 No residue 2 2±0.5 No residue 3 1±2 No residue 4 1.5±1 No residue 5 1±1 No residue 6 1.5±1 No residue 7 2±1 No residue 8 1±3 No residue 9 4±3 Small amount of spot-like residue 10 (No power) 39±14 Completely Residual

[0061] Example 4

[0062] At room temperature, the adhesive matrix is ​​added to a reaction vessel, and ethyl acetate solvent is added at a mass ratio of 1:1 (adhesive matrix to ethyl acetate). The mixture is stirred at 200 rpm for 15 min to mix. Tackifying resin is added at a mass ratio of 2:1 (adhesive matrix to tackifying resin), and stirred for 15 min to mix. Polyether polymer is added at a mass ratio of 10:1 (adhesive matrix to polyether polymer), and stirred for 15 min to mix. Conductive filler is added at a mass ratio of 1:20 (conductive filler to adhesive matrix), and stirred for 15 min to mix, resulting in a homogeneous adhesive solution, which is a biodegradable electrolytic adhesive. The adhesive matrix is ​​polylactic acid-poly(4-methyl-ε-caprolactone), the tackifying resin is a terpene resin, the polyether polymer is polytetrahydrofuran, and the conductive filler is N-ethylpyridine bromide.

[0063] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an electrolytic adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in an electrolytic adhesive tape.

[0064] The electrolytic adhesive tape was subjected to the same peel strength test after being energized as in Example 1, and the test results are shown in Table 10. As can be seen from Table 10, in this example, due to the small amount of conductive filler added, the electrolytic adhesive's electrical response behavior is weakened. After applying a 15V voltage for 1.5 minutes, the peel force decreased by about 88%, which is lower than the ideal debonding effect (95%), indicating a low debonding efficiency.

[0065] Table 10. Peel strength test results of electrolytic adhesive tape after energization 1 0 0 51 Completely Residual 2 5 0.5 41±6 More residue 3 5 1 35±4 Blocky residue 4 5 1.5 10±2 Blocky residue 5 10 0.5 34±5 Blocky residue 6 10 1 10±3 Blocky residue 7 10 1.5 4±1 dotted residue 8 15 0.5 14±2 dotted residue 9 15 1 11±1 No residue 10 15 1.5 6±0.5 No residue

[0066] Example 5

[0067] At room temperature, the adhesive matrix is ​​added to a reaction vessel, and ethyl acetate solvent is added at a mass ratio of 1:1 (adhesive matrix to ethyl acetate). The mixture is stirred at 200 rpm for 15 min to mix. Tackifying resin is added at a mass ratio of 1:1 (adhesive matrix to tackifying resin), and stirred for 15 min to mix. Polyether polymer is added at a mass ratio of 5:1 (adhesive matrix to polyether polymer), and stirred for 15 min to mix. Conductive filler is added at a mass ratio of 1:1 (conductive filler to adhesive matrix), and stirred for 15 min to mix, resulting in a homogeneous adhesive solution, which is a biodegradable electrolytic adhesive. The adhesive matrix is ​​polylactic acid-poly(ε-decyl lactone) block copolymer, the tackifying resin is hydrogenated rosin resin, the polyether polymer is polyethylene glycol, and the conductive filler is a mixture of 1-ethyl-3-methylimidazolium sulfate and poly(3-hexylthiophene) in equal mass ratios.

[0068] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an electrolytic adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in an electrolytic adhesive tape.

[0069] The electrolytic adhesive tape underwent the same peel strength test after energization as in Example 1, and the test results are shown in Table 11. As can be seen from Table 11, in this example, due to the excessive addition of conductive filler, some of the conductive filler underwent macroscopic phase separation from the adhesive matrix. After applying a 15V voltage for 1.5 minutes, the peel strength decreased by approximately 91%, which is lower than the ideal debonding effect (95%). The debonding efficiency of the electrolytic adhesive is low; therefore, the content of conductive filler should not be excessive.

[0070] Table 11. Peel strength test results of electrolytic adhesive tape after energization 1 0 0 34 Completely Residual 2 5 0.5 21±6 Blocky residue 3 5 1 15±4 Blocky residue 4 5 1.5 10±2 Blocky residue 5 10 0.5 14±5 Blocky residue 6 10 1 8±3 Blocky residue 7 10 1.5 4±1 dotted residue 8 15 0.5 12±2 dotted residue 9 15 1 5±1 No residue 10 15 1.5 3±0.5 No residue

[0071] Comparative Example 1: No polyether polymers or conductive fillers added

[0072] At room temperature, the glue matrix is ​​added to the reaction vessel, and ethyl acetate solvent is added at a mass ratio of 1:1 between the glue matrix and ethyl acetate. The mixture is stirred at 200 rpm for 15 min to obtain a uniform glue solution. The glue matrix is ​​a polylactic acid-poly(4-methyl-ε-caprolactone) block copolymer.

[0073] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in the tape.

[0074] The tape was subjected to the same peel strength test after being energized as in Example 1, and the test results are shown in Table 12. As can be seen from Table 12, since no conductive filler was added in this comparative example, the resulting tape exhibited no electrical response behavior, and the peel strength range remained essentially unchanged without fluctuation.

[0075] Table 12 Results of peel strength test of tape after energization 1 0 0 105 Completely Residual 2 5 0.5 112 Completely Residual 3 5 1 109 Completely Residual 4 5 1.5 103 Completely Residual 5 10 0.5 104 Completely Residual 6 10 1 105 Completely Residual 7 10 1.5 109 Completely Residual 8 15 0.5 108 Completely Residual 9 15 1 100 Completely Residual 10 15 1.5 101 Completely Residual

[0076] Comparative Example 2: No polyether polymer added

[0077] At room temperature, the adhesive matrix was added to a reaction vessel, and ethyl acetate solvent was added at a mass ratio of 1:1 (adhesive matrix to ethyl acetate). The mixture was stirred at 200 rpm for 15 min to mix. Tackifying resin was added at a mass ratio of 3:1 (adhesive matrix to tackifying resin), and stirred for 15 min to mix. Conductive filler was added at a mass ratio of 1:10 (conductive filler to adhesive matrix), and stirred for 15 min to mix, resulting in a homogeneous adhesive solution. The adhesive matrix was polylactic acid-poly(4-methyl-ε-caprolactone) block copolymer, the tackifying resin was rosin resin, and the conductive filler was 1-decyl-3-methylimidazolium chloride.

[0078] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in the tape.

[0079] The tape was subjected to the same peel strength test after being energized as in Example 1, and the test results are shown in Table 13.

[0080] Table 13. Peel strength test results of tape after energization 1 0 0 55 Completely Residual 2 5 0.5 43±10 Completely Residual 3 5 1 36±15 Completely Residual 4 5 1.5 31±12 Completely Residual 5 10 0.5 39±9 Completely Residual 6 10 1 28±16 Completely Residual 7 10 1.5 25±9 Completely Residual 8 15 0.5 34±4 Completely Residual 9 15 1 29±11 Completely Residual 10 15 1.5 18±6 Completely Residual

[0081] Comparative Example 3: No conductive filler added

[0082] At room temperature, the adhesive matrix was added to the reactor, and ethyl acetate solvent was added at a mass ratio of 1:1 (adhesive matrix to ethyl acetate). The mixture was stirred at 200 rpm for 15 min to mix. Tackifying resin was added at a mass ratio of 3:1 (adhesive matrix to tackifying resin), and stirred for 15 min to mix. Polyether polymer was added at a mass ratio of 10:1 (adhesive matrix to polyether polymer), and stirred for 15 min to mix, resulting in a homogeneous adhesive solution. The adhesive matrix was polylactic acid-poly(4-methyl-ε-caprolactone) block copolymer, the tackifying resin was rosin resin, and the polyether polymer was polyethylene glycol.

[0083] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in the tape.

[0084] The tape was subjected to the same peel strength test after being energized as in Example 1, and the test results are shown in Table 14.

[0085] Table 14. Peel strength test results of tape after energization 1 0 0 87 Completely Residual 2 5 0.5 83 Completely Residual 3 5 1 85 Completely Residual 4 5 1.5 81 Completely Residual 5 10 0.5 89 Completely Residual 6 10 1 92 Completely Residual 7 10 1.5 86 Completely Residual 8 15 0.5 87 Completely Residual 9 15 1 91 Completely Residual 10 15 1.5 95 Completely Residual

[0086] Comparative Example 4: Using polyacrylic acid resin as the adhesive matrix

[0087] At room temperature, the adhesive matrix was added to a reaction vessel, and ethyl acetate solvent was added at a mass ratio of 1:1 (adhesive matrix to ethyl acetate). The mixture was stirred at 200 rpm for 15 min to mix. Tackifying resin was added at a mass ratio of 3:1 (adhesive matrix to tackifying resin), and stirred for 15 min to mix. Polyether polymer was added at a mass ratio of 10:1 (adhesive matrix to polyether polymer), and stirred for 15 min to mix. Conductive filler was added at a mass ratio of 1:10 (conductive filler to adhesive matrix), and stirred for 15 min to mix, resulting in a homogeneous adhesive solution. The adhesive matrix was polyacrylic acid resin, the tackifying resin was rosin resin, the polyether polymer was polyethylene glycol, and the conductive filler was 1-decyl-3-methylimidazolium chloride.

[0088] The surface of the aluminum foil was sanded for 30 seconds to remove the organic layer. The aforementioned adhesive solution was then applied to the surface of the aluminum foil using a film scraper to obtain an adhesive film with a thickness of 200 μm. A clean PET release film was then adhered to the adhesive film, and a roller was used to ensure a tight bond. The film was then placed in an oven and dried at 90°C for 30 minutes to remove the ethyl acetate, resulting in the tape.

[0089] The adhesive tape was subjected to the same peel strength and degradability tests after being energized as in Example 1, and the test results are shown in Tables 15-16.

[0090] Table 15. Peel strength test results of tape after energization 1 0 0 26 Completely Residual 2 5 0.5 21±4 Completely Residual 3 5 1 18±2 Completely Residual 4 5 1.5 11±4 Completely Residual 5 10 0.5 7±2 Blocky residue 6 10 1 5±4 Blocky residue 7 10 1.5 2±1 dotted residue 8 15 0.5 4±1 dotted residue 9 15 1 2±1 Small amount of spot-like residue 10 15 1.5 2±1 Small amount of spot-like residue

[0091] Table 16 Test Results of Adhesive Tape Degradability 2 0.0317 0.0258 0.0059 0.0054 91.5 4 0.0322 0.0258 0.0064 0.0060 93.8 6 0.0319 0.0258 0.0061 0.0059 96.7 10 0.0336 0.0258 0.0078 0.0078 100 15 0.0326 0.0258 0.0068 0.0062 91.2 20 0.0319 0.0258 0.0061 0.0056 91.8 25 0.0328 0.0258 0.0070 0.0064 91.4 30 0.0322 0.0258 0.0064 0.0059 92.2 40 0.0342 0.0258 0.0084 0.0084 100 55 0.0351 0.0258 0.0093 0.0091 97.8

[0092] After the tape was reused, a peel strength test was performed after applying an electric current. The test results are shown in Table 17. The specific test method is as follows:

[0093] The peeling tape (15 V, 1 min) was then reattached to the stainless steel plate and electrified (15 V, 1 min). The peel strength was tested according to GB / T2792-2014 standard, and the surface of the stainless steel plate was observed for any residual adhesive. The experiment was stopped once all adhesive tape remained.

[0094] Table 17. Peel strength test results of the tape after being energized in repeated experiments. 1 3±2 Small amount of spot-like residue 2 7±8 Blocky residue 3 11±14 Completely Residual

[0095] Compared to Example 1, Comparative Example 1 did not add polyether polymers and conductive fillers. Although the adhesive matrix was not diluted by conductive fillers and polyethers, the adhesive had good cohesive strength and high initial peel strength. However, its peel strength remained basically the same before and after energization. This indicates that without the addition of conductive fillers and polyether polymers, the resulting tape did not exhibit any electrical response debonding behavior and remained completely on the stainless steel surface, making it unusable.

[0096] Compared to Example 1 without the addition of polyether polymers, Comparative Example 2 showed a significantly lower decrease in peel strength under the same energizing time and voltage, leaving complete residue on the stainless steel surface and rendering it unusable. This result indicates that the adhesive tape without polyether polymers exhibits significantly reduced electro-responsive debonding performance, but it is not completely ineffective. Polyether polymers can promote ion migration in the adhesive, accelerate the electroinduced migration rate of conductive fillers, and increase their accumulation at the interface, thereby reducing the electrolytic voltage and shortening the energizing time. Simultaneously, they can dilute the adhesive matrix, soften the adhesive, and improve the interfacial wettability of the adhesive without affecting cohesive strength, thus increasing the peel strength of the electrolytic adhesive when no energization is applied.

[0097] Compared to Example 1, which did not add conductive filler, Comparative Example 3 showed that its peel strength remained basically the same before and after energization, and it remained completely on the stainless steel surface. This indicates that the tape without conductive filler did not exhibit any electrical response debonding behavior and could not be reused.

[0098] Compared to Example 1, Comparative Example 4 changed the adhesive matrix from a fully aliphatic polyester block copolymer to polyacrylic acid resin. Before and after energizing, the peel strength of the tape decreased to some extent, and the peel strength was negatively correlated with the energizing voltage and energizing time. Some residue remained on the stainless steel plate, and the residue level was negatively correlated with the energizing voltage and energizing time. However, in the biodegradability test, the tape quality of Comparative Example 4 did not change significantly within 55 days. The decrease in adhesive quality after degradation may be due to the precipitation and dissolution of a small amount of water-soluble polyether polymers, with adhesive residue rates all exceeding 90%. However, in repeated experiments, due to the limited compatibility between polyether polymers, conductive fillers, and polyacrylic acid resin, the conductive fillers, after interfacial enrichment, were difficult to completely dissolve back into the adhesive matrix. After three repeated experiments, due to the residual conductive fillers, the peel strength of the tape after energizing significantly increased, the electrolytic adhesion effect weakened, and a large amount of residue remained on the stainless steel substrate surface. These experimental results indicate that the non-degradable polyacrylic acid resin adhesive matrix significantly reduces the biodegradability and reusability of the tape, and the peel strength is low when not energized. Compared with common polyacrylic resin adhesives, this application has an adhesive matrix that is biodegradable, does not require curing, and also has improved adhesion.

Claims

1. A degradable electrolytic viscose, characterized in that, The adhesive comprises the following components: a fully aliphatic polyester block copolymer adhesive matrix, conductive filler, polyether polymer additive, and tackifying resin, wherein the mass ratio of each component is: adhesive matrix: conductive filler = 1-20:1, adhesive matrix: tackifying resin = 1-5:1, and adhesive matrix: polyether polymer additive = 5-10:1; the fully aliphatic polyester block copolymer adhesive matrix is ​​composed of hard segments and soft segments, wherein the hard segments are polylactic acid and the soft segments are poly(4-methyl)phenolic resin. The conductive filler is one of 1-ethyl-3-methylimidazolium sulfate, 1-methylimidazolium, N-ethylpyridine bromide, gallium metal, 1-decyl-3-methylimidazolium chloride, and poly(3-hexylthiophene); the polyether polymer additive is at least one of polyethylene glycol, polypropylene glycol, polytetrahydrofuran, and polyethylene glycol-polyethylene block copolymer.

2. Degradable electrolytic viscose according to claim 1, characterized in that, The all-aliphatic polyester block copolymer adhesive matrix is ​​at least one of polylactic acid-poly(4-methyl-ε-caprolactone) block copolymer, polylactic acid-poly(ε-decanoic acid) block copolymer, and polylactic acid-poly(β-methyl-δ-valerolactone) block copolymer.

3. The biodegradable electrolytic adhesive according to claim 1, characterized in that, The tackifying resin is at least one of hydrogenated rosin resin, rosin resin, terpene resin, and C9 petroleum resin.

4. A method for preparing the biodegradable electrolytic adhesive as described in claim 1, characterized in that, Includes the following steps: After dispersing the aliphatic polyester block copolymer adhesive matrix with an organic solvent, tackifying resin, polyether polymer additives, and conductive fillers are added according to the corresponding mass ratios. Each component is stirred and dispersed after addition to obtain a uniform adhesive solution.

5. An electrolytic adhesive film, characterized in that, The preparation is made from the biodegradable electrolytic adhesive according to any one of claims 1-3, wherein the preparation includes coating the electrolytic adhesive onto the surface of a substrate to form an adhesive film.

6. An electrolytic adhesive tape, characterized in that, Includes the biodegradable electrolytic adhesive according to any one of claims 1-3, or the electrolytic adhesive film according to claim 5.

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