Acrylate copolymers containing ionic liquid monomers, methods of making and using the same

Abstract

The application relates to the field of high polymer materials, and particularly discloses an acrylic ester copolymer containing an ionic liquid monomer as well as a preparation method and application thereof. The ionic liquid monomer is capped with an acrylamide group or an acryloyloxy group, is connected to an acrylic ester chain segment main body through a copolymerization mode, and an acrylic ester copolymer solution is obtained. The acrylic ester copolymer solution is made into an electric debonding adhesive layer, the 180-degree peeling strength of which can be reduced by more than 90% under the condition that an applied voltage is less than or equal to 30V and an applied voltage time is less than or equal to 30s, and the performance of the adhesive layer almost does not attenuate after 100 cycles. The problem of high debonding voltage and long debonding time of the acrylic ester pressure-sensitive adhesive is solved. Through aging test, the adhesive layer has high tack, and has no problems of ionic liquid migration, precipitation and surface contamination.

Description

Technical Field

[0001] This application relates to the technical field of polymer materials, and more specifically, to acrylate copolymers containing ionic liquid monomers, their preparation methods, and applications. Background Technology

[0002] Acrylic copolymers are generally the main component of pressure-sensitive adhesives (PSAs), which are typically peeled off mechanically. However, acrylic PSAs can easily damage the substrate and leave adhesive residue. Currently, to impart controllable debonding capabilities to PSAs, research involves physically blending ionic liquids as conductive additives with acrylics. However, this strategy only disperses the ionic liquid within the polymer matrix. During long-term service, the ionic liquid is prone to migration and precipitation, leading to decreased conductivity, interfacial contamination, and deterioration of adhesion performance.

[0003] In related technologies, patent CN116574453B discloses a method for preparing a pressure-sensitive adhesive coating that can be peeled off on demand by applying electricity. It selects 1-vinyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide salt as an ionic liquid monomer and copolymerizes it with various acrylate monomers to obtain a pressure-sensitive adhesive coating. The 180° peel strength of this pressure-sensitive adhesive coating on stainless steel material only decreases by 59.0% after a continuous voltage of 60V for 3 minutes, indicating a slow detack reduction efficiency.

[0004] Based on the above, there is an urgent need in this field to develop a new type of acrylic pressure-sensitive adhesive that can achieve instantaneous and reversible debonding under low voltage. Summary of the Invention

[0005] To address the issues of high tack reduction voltage and long tack reduction time in acrylate pressure-sensitive adhesives, this application provides an acrylate copolymer containing ionic liquid monomers, its preparation method, and its application.

[0006] In a first aspect, this application provides an acrylate copolymer containing an ionic liquid monomer, employing the following technical solution: An acrylate copolymer containing an ionic liquid monomer comprises the following components in parts by weight: 2-5 parts acrylic monomer; 60-80 parts of acrylate hard monomer; 10-20 parts of acrylate soft monomer; 5-20 parts of ionic liquid monomer; Initiator 0.5-2 parts; Chain transfer agent 0-0.3 parts; The general structural formula of ionic liquid monomers is as follows: CH2=CR 1 -L-[N⊕(R 2 )-Z]X ; Among them, R 1 It is H or CH3; L stands for -(CH2) n -or-(CH2) n -COO- or -(CH2) n -CONH-, n=2-6; R 2 =C1-C 12 Straight-chain / branched alkyl, aryl, or functionalized alkyl groups Z is the linking segment that forms a quaternary ammonium or heterocyclic cation together with N⊕; X It can be any one of inorganic acid radicals, organic acid radicals, negatively charged anions formed after active nonmetallic elements gain electrons, and organic anions produced by the deprotonation of organic compounds.

[0007] Furthermore, the ionic liquid monomer is ILM-1, and the structural formula of ILM-1 is as follows:

[0008] Furthermore, the ionic liquid monomer is ILM-2, and the structural formula of ILM-2 is as follows:

[0009] Furthermore, the ionic liquid monomer is ILM-3, and the structural formula of ILM-3 is as follows:

[0010] Furthermore, the ionic liquid monomer is ILM-4, and the structural formula of ILM-4 is as follows:

[0011] Furthermore, X For Cl - ,Br - I - SCN - BF4 - BF6 - PF6 - FSI - TFSI - or NTf2 - .

[0012] Furthermore, the amount of the ionic liquid monomer added accounts for 5-15 wt% of the total monomer amount; wherein, the total monomer amount consists of acrylic acid monomer, acrylate hard monomer, acrylate soft monomer and ionic liquid monomer.

[0013] Furthermore, the acrylate hard monomer is selected from one or more of 2-ethyl acrylate, methyl methacrylate, cyclohexyl acrylate and 2-hydroxy-3-phenoxypropyl acrylate.

[0014] Furthermore, the acrylate soft monomer is selected from one or more of butyl acrylate, isooctyl acrylate, lauryl acrylate, and 2-methoxyethyl acrylate.

[0015] Furthermore, the initiator is selected as either a free radical photoinitiator or a cationic photoinitiator. More specifically, the free radical photoinitiator selection includes α-hydroxy ketone initiators, benzoyl carbamate initiators, α-amino ketone initiators, acylphosphine oxide initiators, and acetophenone derivative initiators; more specifically, the following brands of free radical photoinitiators are selected: Irgacure 1173, Irgacure 1184, Irgacure 754, Irgacure 369, Irgacure 907, Irgacure TPO, Irgacure 819, and Darocur MBF. The cationic photoinitiator selection includes metallocene photoinitiators; more specifically, the following brand of metallocene photoinitiators is selected: Irgacure 261.

[0016] Furthermore, the chain transfer agent may be selected from one or more of dodecyl mercaptoethanol, mercaptopropionic acid, and pentaerythritol tetra-3-mercaptopropionate.

[0017] Secondly, this application provides a method for preparing an acrylate copolymer containing an ionic liquid monomer, using the following technical solution: A method for preparing an acrylate copolymer containing an ionic liquid monomer includes the following steps: Acrylic acid, hard acrylate monomers, soft acrylate monomers, ionic liquid monomers, initiators, and chain transfer agents are dissolved in an organic solvent under an inert atmosphere, with the solid content controlled at 30-70 wt%, and the acrylate copolymer solution is obtained by thermal reaction copolymerization or irradiation copolymerization.

[0018] Furthermore, the specific operation of the thermal reactive copolymerization is as follows: react at 20-80℃ for 2-8 hours.

[0019] Furthermore, the specific operation of the irradiation copolymerization is to use 365nm ultraviolet light to initiate the process, with an irradiation time of 2-6 minutes.

[0020] Furthermore, the weight-average molecular weight of the acrylate copolymer is controlled between 300,000 and 600,000.

[0021] Furthermore, the glass transition temperature of the acrylate copolymer is -55°C to -40°C.

[0022] Thirdly, this application provides an application of an acrylate copolymer containing an ionic liquid monomer, employing the following technical solution: Application of an acrylate copolymer containing an ionic liquid monomer, wherein the aforementioned acrylate copolymer containing an ionic liquid monomer is coated on a substrate and cured to form an electro-tack adhesive layer.

[0023] Furthermore, the surface resistivity of the electro-tack adhesive layer is controlled at 10. 4 -10 6 Ω / sq.

[0024] Furthermore, the electro-tack reducing adhesive layer exhibits a 180° peel strength reduction of over 90% when the applied voltage is ≤30V and the applied voltage time is ≤30s.

[0025] By adopting the above technical solution, this application has at least the following advantages: First, this application designs a novel ionic liquid monomer, which is end-capped with acrylamide or acryloyloxy groups, enabling it to copolymerize with acrylic acid, hard acrylate monomers, and soft acrylate monomers to obtain acrylate copolymer solutions. The ionic liquid monomer is covalently integrated into the acrylate backbone, avoiding the common problems of ionic liquid migration, precipitation, and surface contamination in simple physical blending systems.

[0026] This acrylate copolymer solution can be coated onto a substrate and cured to obtain an electro-tack reducing adhesive layer. This electro-tack reducing adhesive layer can achieve a 180° peel strength reduction of more than 90% under the conditions of an applied voltage ≤30V and an applied voltage time ≤30s, thus achieving an instantaneous and significant reduction in adhesion.

[0027] Furthermore, the adhesion of the electro-tack reducing adhesive layer can recover to more than 90% of the initial adhesion after 15 seconds of power failure, and the performance of the electro-tack reducing adhesive layer hardly declines after more than 100 cycles.

[0028] Second, this application further explores the effect of structural changes of ionic liquid monomers on the electro-tack reduction properties of electro-tack adhesive layers; according to the test data, the higher the rigidity of the end cap groups and the shorter the distance between the double bond and the cation, the more significant the improvement in tack reduction efficiency.

[0029] Third, this application further investigates the effect of the amount of ionic liquid monomer added on the electro-tack reduction properties of the electro-tack reduction adhesive layer. According to the test data, as the amount of ILM increases from 5 wt% to 15 wt%, the tack reduction efficiency continuously improves, while the initial peel force and cycle performance slightly decrease. This indicates that the increased cation density shortens the electric field response distance, allowing sufficient interfacial charge shielding to be formed even at low voltages. It also reveals that excessive cation microdomains tend to connect, leading to increased rigidity and limited reversibility of the glassy network. Detailed Implementation

[0030] In this field, ionic liquids are typically used as conductive additives and physically blended with the main components of acrylic pressure-sensitive adhesives to impart the adhesive with the ability to peel off as needed when energized. However, this approach is prone to problems such as ionic liquid migration. To address this issue, patent CN116574453B uses a vinylimidazolium-based ionic liquid monomer (1-vinyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide salt) to modify the acrylic pressure-sensitive adhesive; however, after actual testing, the resulting pressure-sensitive adhesive coating agent was found to require continuous energization at a medium-high voltage of 60V for 3 minutes before the 180° peel strength decreased to 59.0%, indicating a long detack reduction time and high required voltage.

[0031] In response to this situation, the applicant further optimized the structure of the ionic liquid monomer by using acrylamide or acryloyloxy groups to cap the imidazole or bipyridine groups, and then covalently attaching the ionic liquid monomer to the acrylate backbone. The resulting acrylate copolymer can reduce the 180° peel strength by more than 90% when the applied voltage is ≤30V and the applied voltage time is ≤30s, thus achieving a significant reduction in adhesion force instantly.

[0032] This application uses acryloyloxy or acrylamide groups for direct end capping, and anchors the imidazole / bipyridine cation to the polymerizable double bond through 2-6 methylene short chains, thereby reducing the distance between the cation and the main chain and improving the orientation rigidity. The "proximal anchoring + rapid orientation" structure can achieve low-voltage, instantaneous, reversible, and highly efficient electro-induced viscosity reduction.

[0033] This application is further illustrated by the following preparation examples, embodiments, comparative examples, application examples, and detection data.

[0034] Unless otherwise specified, the raw materials used in the preparation examples and embodiments in this application are all commercially available and have a purity of 99.9%.

[0035] Preparation Example 1 An ionic liquid monomer, ILM-1, has the following structural formula:

[0036] Prepare according to the following steps: 32.84 g of 1-methylimidazole and 49.98 g of 2-bromoethanol were added to a three-necked flask equipped with a stirrer, a nitrogen inlet and a reflux condenser. The mixture was refluxed at 80 °C for 12 h with 200 mL of acetonitrile as solvent. The solvent was removed by rotary evaporation to obtain 1-(2-hydroxyethyl)-3-methylimidazole bromide. 41.41 g of the obtained 1-(2-hydroxyethyl)-3-methylimidazolium bromide was dissolved in 150 mL of CH2Cl2, and 19.91 g of acryloyl chloride and 22.26 g of triethylamine were added dropwise under ice bath. The reaction was carried out at room temperature for 4 h, and then transferred to a separatory funnel. The solution was washed with saturated NaHCO3, dried over anhydrous MgSO4, and evaporated to dryness to obtain acrylated bromide. The acrylated bromide salt was dissolved in deionized water and 57.42 g of LiNTf2 was added. The mixture was stirred overnight at room temperature, and a white solid precipitated. The solid was filtered and recrystallized to obtain the ionic liquid monomer ILM-1 with a yield of 78%.

[0037] Preparation Example 2 An ionic liquid monomer, ILM-2, has the following structural formula:

[0038] Prepare according to the following steps: 24.84 g of 1-butylimidazolium and 18.91 g of 3-chloro-1-propanol were added to a three-necked flask equipped with a stirrer, a nitrogen inlet, and a reflux condenser. 27.64 g of K2CO3 was added to 100 mL of toluene as solvent, and the mixture was heated to 100 °C and reacted for 6 h. After cooling, the mixture was filtered and rotary evaporated under reduced pressure to obtain 1-(3-hydroxypropyl)-3-butylimidazolium chloride. 1-(3-hydroxypropyl)-3-butylimidazolium chloride was dissolved in 150 mL of CH2Cl2, and 19.91 g of acryloyl chloride and 22.26 g of triethylamine were added dropwise under ice bath conditions. The reaction was carried out at room temperature for 5 h. The reaction solution was washed with saturated NaHCO3, dried over anhydrous MgSO4, and then rotary evaporated to obtain acrylated chloride. The acrylate chloride salt was dissolved in deionized water, and 24.16 g of NaBF4 was added. The mixture was stirred overnight at room temperature, and a white solid precipitated. The solid was filtered and recrystallized (acetonitrile / ethyl acetate) to give ILM-2 with a yield of 73%.

[0039] ¹H-NMR(400MHz, CDCl3)δ0.93 (t,3H), 1.31-1.91(m,6H), 4.17(t,2H), 4.34(t,2H), 5.83(dd,1H), 6.12(dd,1H), 6.40(dd,1H), 7.38(s,1H),7.42(s,1H),9.05(s,1H).

[0040] Preparation Example 3 An ionic liquid monomer, ILM-3, has the following structural formula:

[0041] Prepare according to the following steps: 15.62 g of 4,4'-bipyridine and 30.57 g of 3-bromopropanol were reacted in acetonitrile at 85 °C for 12 h to give N,N'-bis(3-hydroxypropyl)-4,4'-bipyridine onium dibromide. N,N'-bis(3-hydroxypropyl)-4,4'-bipyridinium dibromide was reacted with 25.09 g of methacryloyl chloride in a CH2Cl2 / triethylamine system at 0 °C for 6 h to give bis(methacrylate)bipyridinium dibromide; Dissolve bis(methacrylate) bipyridinium dibromide in deionized water, add 63.16 g of LiNTf2, stir overnight at room temperature, and a pale yellow solid precipitates. Filter and recrystallize to obtain ILM-3 with a yield of 68%.

[0042] Preparation Example 4 An ionic liquid monomer, ILM-4, has the following structural formula:

[0043] Prepare according to the following steps: 29.73 g of 3-chloropropylacrylamide and 24.84 g of 1-butylimidazolium were reacted in isopropanol at 80 °C for 6 h to give 1-(acrylamidopropyl)-3-butylimidazolium chloride. 1-(acrylamidopropyl)-3-butylimidazolium chloride was dissolved in deionized water and then KPF6 33.66 g was added. The mixture was stirred overnight at room temperature, and a white solid precipitated. After filtration and recrystallization, ILM-4 was obtained with a yield of 70%.

[0044] Example

[0045] Example 1

[0046] An acrylate copolymer containing an ionic liquid monomer is prepared according to the following steps: 70g of 2-ethyl acrylate (EHA), 15g of butyl acrylate (BA), 3g of acrylic acid (AA), 12g of ionic liquid monomer ILM-1, 1.0g of photoinitiator Irgacure 1173, 0.1g of n-dodecyl mercaptan, and 100g of ethyl acetate were added sequentially to a reaction vessel. After bubbling with nitrogen for 10 minutes, the mixture was irradiated under a 365nm LED ultraviolet lamp at 25℃ with an irradiation intensity of 10mW / cm². 2 Irradiation for 5 minutes yields an acrylate copolymer solution (M). w =3.8×10 5 (PDI=1.9). The amount of ionic liquid monomer ILM-1 added accounts for 12 wt% of the total monomer.

[0047] Examples 2-4 An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that the source of the ionic liquid monomer is different, as detailed below: In Example 2, the ionic liquid monomer was ILM-2; In Example 3, the ionic liquid monomer was ILM-3; In Example 4, the ionic liquid monomer was ILM-4.

[0048] Example 5

[0049] An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that the amount of ionic liquid monomer added is different, specifically, the amount of ionic liquid monomer ILM-1 added accounts for 5 wt% of the total monomer.

[0050] Example 6

[0051] An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that the amount of ionic liquid monomer added is different, specifically, the amount of ionic liquid monomer ILM-1 added accounts for 15 wt% of the total monomer.

[0052] Example 7

[0053] An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that its composition is different, specifically: In a reaction vessel, 65g of 2-ethyl acrylate (EHA), 20g of butyl acrylate (BA), 3g of acrylic acid (AA), 15g of ionic liquid monomer ILM-2, 1.2g of photoinitiator Irgacure 651, 0.15g of n-dodecyl mercaptan, and 110g of ethyl acetate were added sequentially. After bubbling with nitrogen for 10 minutes, the mixture was irradiated under a 365nm LED ultraviolet lamp at 25℃ with an irradiation intensity of 10mW / cm². 2 Irradiation for 5 minutes yields an acrylate copolymer solution (M). w =4.1×10 5 (PDI=1.9). The amount of ionic liquid monomer ILM-2 added accounts for 14.56 wt% of the total monomer.

[0054] Example 8

[0055] An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that its composition is different, specifically: 60g of 2-ethyl acrylate (EHA), 18g of butyl acrylate (BA), 4g of acrylic acid (AA), 10g of ionic liquid monomer ILM-3, 1.0g of photoinitiator TPO-L, and 100g of butyl acetate were added sequentially to a reaction vessel. After bubbling with nitrogen for 10 minutes, the mixture was irradiated under a 365nm LED ultraviolet lamp at 25℃ with an irradiation intensity of 10mW / cm². 2 Irradiation for 7 minutes yields an acrylate copolymer solution (M). w =3.9×10 5 (PDI=1.9). The amount of ionic liquid monomer ILM-3 added accounts for 10.9 wt% of the total monomer.

[0056] Example 9

[0057] An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that its composition is different, specifically: 68g of 2-ethyl acrylate (EHA), 15g of butyl acrylate (BA), 3g of acrylic acid (AA), 12g of ionic liquid monomer ILM-1, 0.3g of trimethylolpropane triacrylate (TMPTA), 1.0g of initiator Irgacure 1173, and 100g of ethyl acetate were added sequentially to the reaction vessel. After bubbling with nitrogen for 10 min, the mixture was irradiated under a 365nm LED ultraviolet lamp at 25℃ with an irradiation intensity of 10mW / cm². 2 Irradiation for 5 minutes yields an acrylate copolymer solution (M). w =4.0×10 5 (PDI=2.2). The amount of ionic liquid monomer ILM-4 added accounts for 12.2 wt% of the total monomer.

[0058] Example 10

[0059] An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that its composition is different, specifically: 62g of 2-ethyl acrylate (EHA), 20g of butyl acrylate (BA), 5g of acrylic acid (AA), 13g of ionic liquid monomer ILM-4, 1.2g of initiator Irgacure 2959, and 100g of an aqueous ethanol solution (volume ratio of ethanol:water = 7:3) were added sequentially to the reaction vessel. After bubbling with nitrogen for 10 minutes, the mixture was irradiated under a 365nm LED ultraviolet lamp at 25℃ with an irradiation intensity of 10mW / cm². 2 Irradiation for 5 minutes yields an acrylate copolymer solution (M). w =3.5×10 5 (PDI=2.1). The amount of ionic liquid monomer ILM-4 added accounts for 13 wt% of the total monomer.

[0060] Comparative Example

[0061] Comparative Example 1 An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that an equal part by weight of the ionic liquid monomer ILM-1 is replaced with 1-ethyl-3-methylimidazoline bis(trifluoromethanesulfonyl)imide.

[0062] Comparative Example 2 An acrylate copolymer containing an ionic liquid monomer differs from Example 1 in that an equal weight portion of the ionic liquid monomer ILM-1 is replaced with 1-vinyl-3-butylimidazolium bis(trifluoromethanesulfonyl)imide salt.

[0063] Application examples and comparisons

[0064] An electro-tack reducing adhesive layer is prepared according to the following steps: The acrylate copolymer solution containing ionic liquid monomers prepared in the examples or comparative examples is coated onto a 50µm PET substrate. The substrate is then baked and cured at 100°C for 3 minutes, resulting in a dry thickness of 25µm for the electro-tack adhesive layer. After cooling, a release film is applied to obtain the electro-tack pressure-sensitive tape.

[0065] Application Examples 1-10 and Comparative Examples 1-2 were prepared in the same manner as described above, with the only difference being the source of the acrylate copolymer solution containing the ionic liquid monomer, as detailed below: The acrylate copolymer solution containing ionic liquid monomers in Application Example 1 is derived from Example 1; The acrylate copolymer solution containing ionic liquid monomers in Application Example 2 is derived from Example 2; The acrylate copolymer solution containing ionic liquid monomers in Application Example 3 is derived from Example 3; The acrylate copolymer solution containing ionic liquid monomers in Application Example 4 is derived from Example 4; The acrylate copolymer solution containing ionic liquid monomers in Application Example 5 is derived from Example 5; The acrylate copolymer solution containing ionic liquid monomers in Application Example 6 is derived from Example 6; The acrylate copolymer solution containing ionic liquid monomers in Application Example 7 is derived from Example 7; The acrylate copolymer solution containing ionic liquid monomers in Application Example 8 is derived from Example 8; The acrylate copolymer solution containing ionic liquid monomers in Application Example 9 is derived from Example 9; The acrylate copolymer solution containing ionic liquid monomers in Application Example 10 is derived from Example 10; The acrylate copolymer solution containing ionic liquid monomers used in Comparative Example 1 was derived from Comparative Example 1; The acrylate copolymer solution containing ionic liquid monomers used in Comparative Example 2 was derived from Comparative Example 2.

[0066] Detection method 1. Electro-induced viscosity reduction properties 1.1.180° Peel Strength: Performed according to GB / T 2792-2014, with a sample width of 25 mm; after bonding to the stainless steel plate, use a 2 kg rubber roller to roll back and forth once; let stand for 20 min; tensile speed 300 mm / min; record the initial peel force F0.

[0067] 1.2. Anti-adhesion efficiency: Apply a set voltage V (5-30V) to the test sample in 1.1 for a duration of t (5-30s); immediately test the 180° peel strength according to the test method in 1.1 and record the electric field peel force F1; after power is turned off, let it stand for 60s, and measure the 180° peel strength again and record the recovery force F2; Anti-adhesion efficiency = (F0-F1) / F0×100%.

[0068] 1.3. Cyclic Retention Rate: Repeat step 1.2 100 times and record F2 after 100 cycles. ’ Cycle retention rate = F2 ’ / F0×100%.

[0069] 2. Thermal aging test The tape was placed in an 85℃ forced-air drying oven for 168 hours, then removed and allowed to equilibrate to room temperature for 2 hours before the following tests were performed: 2.1. Holding power: Test the 180° peel strength according to the method recorded in 1.1, record the peel strength F3, and calculate the holding power = F3 / F0 × 100%.

[0070] 2.2. Ion migration: A 50 µm aluminum foil was attached to the adhesive tape surface for 24 h. After removal, the Na content on the aluminum foil surface was measured by ICP-OES. + BF4 - PF6 - NTf2 - Quantity; any ion detection amount <0.1µg / cm 2 It was determined to be "no migration".

[0071] 3. Surface resistivity The four-probe method recorded in GB / T 3048.3-2007 was used, with a probe spacing of 1 mm, and 5 points were tested, with the average value taken.

[0072] Test results Table 1. Results of electro-viscosity reduction performance tests for Application Examples 1-10 and Comparative Examples 1-2.

[0073]

[0074] Note: Application Example 10 shows that the in vitro cytotoxicity test (ISO 10993-5) shows that the cell viability is >90%, which meets the medical requirements.

[0075] In Comparative Example 1, the retention rate was only 60% after 30 cycles, and after 100 cycles, the retention rate could not be detected.

[0076] Table 2. Results of thermal aging tests and surface resistance measurements for Application Examples 1-10 and Comparative Examples 1-2.

[0077]

[0078] in conclusion Based on the above test data, it can be seen that the application example of this application can reduce the 180° peel strength by more than 87% (up to 96%) within ≤30V and ≤30s, with a recovery rate of ≥88% after 15s of power failure, and the retention rate still remains at around 90% after 100 cycles; while the comparative application example requires 60V and 2min to reduce the peel strength by 59%, and drops to 60% after 30 cycles. After heat aging at 85℃ for 168h, the application example has a holding power retention rate of 93-95%, no ion migration was detected on the aluminum foil surface, and the surface resistance is stable at 1-3×10. 4 Ω / sq; In comparative applications, the viscosity retention is only 40-42%, with 8 at% oil accumulation and the resistance rising to 10 Ω / sq. 6 Ω / sq. As the ILM dosage increased from 5wt% to 15wt%, the detack reduction efficiency continued to improve, while the initial peel force and cycle performance decreased slightly. Mild crosslinking with 0.3wt% TMPTA effectively improved the initial peel force and electro-detack reduction efficiency. In summary, this application, through a novel ionic liquid monomer of "acryloyloxy / amide end-capping + short-chain anchoring," covalently bonded to the acrylate backbone, completely solves the industry problems of ion migration, precipitation, and interface contamination in physical blending systems. Simultaneously, it possesses low voltage transient response, high cycle stability, no residue and no contamination, and electronic-grade surface resistivity (10 Ω / sq). 4 -10 6 Ω·sq -1 It possesses outstanding creativity, practicality, and industrial application value.

[0079] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An acrylate copolymer containing an ionic liquid monomer, characterized in that: The components include the following parts by weight: 2-5 parts acrylic monomer; 60-80 parts of acrylate hard monomer; 10-20 parts of acrylate soft monomer; 5-20 parts of ionic liquid monomer; Initiator 0.5-2 parts; Chain transfer agent 0-0.3 parts; The general structural formula of ionic liquid monomers is as follows: CH2=CR 1 -L-[N⊕(R 2 )-Z]X ; Among them, R 1 It is H or CH3; L stands for -(CH2) n -or-(CH2) n -COO- or -(CH2) n -CONH-, n=2-6; R 2 =C1-C 12 Straight-chain / branched alkyl, aryl, or functionalized alkyl groups Z is the linking segment that forms a quaternary ammonium or heterocyclic cation together with N⊕; X It can be any one of inorganic acid radicals, organic acid radicals, negatively charged anions formed after active nonmetallic elements gain electrons, and organic anions produced by the deprotonation of organic compounds.

2. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that, The ionic liquid monomer is ILM-1, and the structural formula of ILM-1 is as follows: .

3. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that, The ionic liquid monomer is ILM-2, and the structural formula of ILM-2 is as follows: .

4. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that, The ionic liquid monomer is ILM-3, and the structural formula of ILM-3 is as follows: .

5. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that, The ionic liquid monomer is ILM-4, and the structural formula of ILM-4 is as follows: .

6. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that: The amount of ionic liquid monomer added accounts for 5-15 wt% of the total monomer amount; wherein the total monomer amount consists of acrylic acid monomer, acrylate hard monomer, acrylate soft monomer and ionic liquid monomer.

7. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that: The acrylate hard monomer is selected from one or more of 2-ethyl ethyl acrylate, methyl methacrylate, cyclohexyl acrylate and 2-hydroxy-3-phenoxypropyl acrylate.

8. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that: The acrylate soft monomer is selected from one or more of butyl acrylate, isooctyl acrylate, lauryl acrylate, and 2-methoxyethyl acrylate.

9. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that: The initiator is selected as a free radical photoinitiator.

10. The acrylate copolymer containing an ionic liquid monomer as described in claim 1, characterized in that: The chain transfer agent is selected from one or more of dodecyl mercaptoethanol, mercaptopropionic acid, and pentaerythritol tetra-3-mercaptopropionate.

11. The method for preparing the acrylate copolymer containing an ionic liquid monomer according to any one of claims 1-10, characterized in that, Includes the following steps: Acrylic acid, hard acrylate monomers, soft acrylate monomers, ionic liquid monomers, initiators, and chain transfer agents are dissolved in an organic solvent under an inert atmosphere, with the solid content controlled at 30-70 wt%, and the acrylate copolymer solution is obtained by thermal reaction copolymerization or irradiation copolymerization.

12. The method for preparing the acrylate copolymer containing an ionic liquid monomer as described in claim 11, characterized in that: The specific operation of the irradiation copolymerization is to use 365nm ultraviolet light to initiate the process, with an irradiation time of 2-6 minutes.

13. The method for preparing the acrylate copolymer containing an ionic liquid monomer as described in claim 11, characterized in that: The weight-average molecular weight of the acrylate copolymer is controlled between 300,000 and 600,000.

14. The method for preparing the acrylate copolymer containing an ionic liquid monomer as described in claim 11, characterized in that: The glass transition temperature of the acrylate copolymer is -55°C to -40°C.

15. The application of an acrylate copolymer containing an ionic liquid monomer, characterized in that: The acrylate copolymer containing ionic liquid monomers as described in any one of claims 1-10 is coated on a substrate and cured to form an electro-tack adhesive layer.

16. The application of the acrylate copolymer containing an ionic liquid monomer as described in claim 15, characterized in that: The surface resistance of the electro-tack adhesive layer is controlled at 10. 4 -10 6 Ω / sq.

17. The application of the acrylate copolymer containing an ionic liquid monomer as described in claim 15, characterized in that: The electro-tack reducing adhesive layer exhibits a 180° peel strength reduction of over 90% when the applied voltage is ≤30V and the applied voltage time is ≤30s.

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