Preparation method of high-elasticity printing rubber blanket

Abstract

The invention relates to the field of rubber blanket production and processing, and particularly discloses a high-elasticity printing rubber blanket which comprises maleic anhydride grafted ethylene propylene diene monomer for a surface layer, core-shell nanoparticles, hydrogenated butadiene-acrylonitrile rubber for a compressible layer, a crystalline polyethylene glycol sacrificial template agent and a multifunctional acrylate cross-linking agent, the synergistic auxiliary agent system comprises the following components: a microcapsule self-repairing agent, a polymerization catalyst, a reactive block copolymer surfactant and flaky hexagonal boron nitride; the preparation method comprises the following steps: S1, preparing a composite sizing material; S2, integrally compounding; S3, carrying out radiation curing; and S4, carrying out post-treatment molding. A synergistic auxiliary aid system of a microcapsule self-repairing agent and a polymerization catalyst is compounded in the surface layer rubber, the healing agent can be subjected to in-situ polymerization under the action of the catalyst to repair damage, and the beneficial effects of actively inhibiting fatigue crack propagation and remarkably prolonging the overall service life of the rubber blanket are achieved.

Description

TECHNICAL FIELD

[0001] The application relates to the field of rubber blanket production and processing, in particular to a preparation method of high-elasticity printing rubber blanket. BACKGROUND

[0002] As a core consumable component in the offset printing technology, the printing rubber blanket mainly functions as an intermediate carrier for image transfer in the printing process, accurately transferring the graphic information on the printing plate to the surface of the printing material. It is usually composed of multiple layers such as a printing layer on the surface, a compression layer in the middle and a fabric base cloth at the bottom. The physical properties, chemical stability and surface characteristics of a printing rubber blanket with excellent performance directly determine the dot reproduction accuracy, color saturation and overall quality of the final printed product, and therefore play a crucial role in the modern high-speed and high-precision printing field.

[0003] In related technologies, the preparation of the printing rubber blanket generally involves mixing a rubber base including nitrile rubber with conventional fillers including carbon black or white carbon black to prepare a rubber compound for the printing layer and the compression layer. The porous structure of the compression layer is generally realized by adding a chemical foaming agent or prefabricated hollow glass microspheres to the rubber compound. Subsequently, the rubber compounds of the respective layers are sequentially compounded onto the fabric base cloth by coating or calendering, and finally, heat vulcanization is performed under high temperature and high pressure for a long time to cross-link and solidify the layers and bond them together, and finally, the finished product is formed after polishing and other processes. Some previous schemes select rubbers with better wear resistance or adjust the ratio of fillers in order to improve the durability of the printing rubber blanket to some extent. SUMMARY

[0004] In order to solve the problem in the related art that the surface layer of the printing rubber blanket lacks any active repair mechanism after being subjected to compression, mechanical friction and chemical corrosion of ink and cleaning agents, the micro defects become stress concentration points, continuously expand and converge in the subsequent printing cycle, and finally lead to surface fatigue, cracking and performance degradation, the application provides a preparation method of high-elasticity printing rubber blanket.

[0005] In a first aspect, the application provides a high-elasticity printing rubber blanket, which adopts the following technical scheme: A high-elasticity printing rubber blanket comprises: maleic anhydride grafted ethylene propylene diene rubber, core-shell nanoparticles for the surface layer, hydrogenated nitrile rubber for the compressible layer, crystalline polyethylene glycol sacrificial template agent and multifunctional acrylate crosslinking agent; and a synergistic auxiliary agent system comprising the following components: microcapsule self-repairing agent, polymerization catalyst, reactive block copolymer surfactant and flaky hexagonal boron nitride.

[0006] By adopting the above technical scheme, since the synergistic auxiliary additive system containing the microcapsule self-repairing agent, the reactive block copolymer surfactant and the flaky hexagonal boron nitride is adopted, the system gives the surface layer the ability of actively repairing micro-crack damage, the gradient pore structure in the compressible layer is chemically anchored by the reactive surfactant, and a high-efficiency internal heat conduction network is constructed in the compressible layer by the flaky hexagonal boron nitride, therefore, the comprehensive performance of integrating the active damage repair, the high resilience stability and the excellent heat management function is obtained, so that the blanket can significantly prolong the service life and continuously maintain the stable dot reproduction accuracy and the ink transfer efficiency under the printing working condition of high speed and long time, and the defects of short product life and poor high-speed printing stability in the related technologies are solved.

[0007] Preferably, the weight parts combination comprises: 50-100 parts of maleic anhydride grafted EPDM for the surface layer, 15-25 parts of core-shell nanoparticles, 50-100 parts of hydrogenated nitrile rubber for the compressible layer, 60-80 parts of crystalline polyethylene glycol sacrificial template agent and 13-18 parts of multifunctional acrylate crosslinking agent; and a synergistic auxiliary additive system comprising the following components: 1-5 parts of microcapsule self-repairing agent, 0.05-0.2 parts of polymerization catalyst, 2-8 parts of reactive block copolymer surfactant and 3-10 parts of flaky hexagonal boron nitride; The microcapsule self-repairing agent is a microcapsule with polyurethane or polyurea as the wall material and coated with a liquid healing agent; the polymerization catalyst is a solid-phase catalyst dispersed in the rubber matrix.

[0008] Preferably, the liquid healing agent is dicyclopentadiene; and the polymerization catalyst is Grubbs catalyst.

[0009] Preferably, the reactive block copolymer surfactant is an acrylate group terminated polyethylene glycol-block-poly-caprolactone.

[0010] Preferably, the flaky hexagonal boron nitride has an average flake diameter of 1-5 μm and is distributed in the compressible layer.

[0011] Preferably, the core-shell nanoparticles are composite nanoparticles with spherical silica with a particle size of 30-50 nm as the core and perfluoropolyether as the shell.

[0012] Preferably, the crystalline polyethylene glycol sacrificial template agent is composed of a first crystalline polyethylene glycol with an average particle size of 30-50 μm and a second crystalline polyethylene glycol with an average particle size of 5-10 μm.

[0013] By adopting the above technical solution, due to the use of a synergistic auxiliary agent system and functionalized materials, the microcapsule self-healing system in the surface layer can actively perform in-situ polymerization repair when the material suffers microscopic damage; the gradient pore structure constructed by dual-size sacrificial template agents in the compressible layer optimizes the dynamic compression response, while the reactive block copolymer surfactant chemically anchors the pore walls, enhancing structural stability; at the same time, the lamellar hexagonal boron nitride distributed in the compressible layer forms an efficient internal thermal conductivity network. Therefore, a comprehensive beneficial effect is achieved, integrating active fatigue repair, high resilience stability, precise pressure transmission, and excellent thermal management functions, significantly extending the service life of the blanket under high-intensity working conditions, and ensuring the dot reproduction accuracy and quality consistency in high-speed printing processes.

[0014] Secondly, this application provides a method for preparing a highly elastic printing rubber blanket, employing the following technical solution: A method for preparing a highly elastic printing blanket includes the following steps: S1. Preparation of composite rubber compound: Maleic anhydride-grafted EPDM rubber, surface-functionalized core-shell nanoparticles, microcapsule self-healing agent, polymerization catalyst, and multifunctional acrylate crosslinking agent are mixed to obtain surface layer composite rubber compound; hydrogenated nitrile butadiene rubber, crystalline polyethylene glycol sacrificial template agent, reactive block copolymer surfactant, flake hexagonal boron nitride, and multifunctional acrylate crosslinking agent are mixed to obtain compressible layer composite rubber compound; S2, Integrated Composite: The surface layer composite material and the compressible layer composite material are composited onto the fabric base through multi-layer co-extrusion technology to form a multi-layer composite with a gradient structure; S3. Radiation curing: The multilayer composite is cured in an integrated manner by electron beam radiation to form chemical bonds between the layers, thereby obtaining a cured semi-finished product. S4. Post-processing molding: Solvent extraction is performed on the cured semi-finished product to remove the sacrificial template agent in the compressible layer, forming a gradient pore structure, and the surface layer is precisely ground to obtain the final product.

[0015] By adopting the above technical solution, an integrated manufacturing process combining the preparation of functionalized composite materials, dynamic co-extrusion molding of gradient structures, and overall electron beam radiation curing is employed. This process utilizes electron beam radiation to achieve integrated rapid curing at low temperatures, effectively avoiding the damage to heat-sensitive components such as microcapsule self-healing agents caused by traditional high-temperature vulcanization. Furthermore, it forms strong chemical bonds between the surface layer, compressible layer, and fabric base. Simultaneously, a gradient pore structure is precisely constructed through dynamic co-extrusion and subsequent solvent extraction. Therefore, it achieves a comprehensive benefit of high production efficiency, strong bonding of functional layers, and maximum preservation and utilization of advanced materials, including self-healing and thermal management preset properties, ensuring a high degree of unity between the structural integrity and functionality of the final product.

[0016] Preferably, in step S1, before preparing the surface layer composite adhesive, the core-shell nanoparticles are pretreated as follows: The surface of the material was chemically modified with γ-aminopropyltriethoxysilane to introduce active functional groups. In the preparation of compressible layer composite rubber, aluminum hydroxide or magnesium hydroxide is added as a flame retardant, and its dosage is 5 to 15 parts by weight of hydrogenated nitrile rubber. After completing the above steps, proceed to the following steps: In step S2, a multi-layer co-extrusion die head integrating a programmable dynamic proportioning mixing system is used to achieve the desired effect within a transition time of 0.5 to 1.5 seconds. The particle size distribution of the sacrificial template agent used in the compressible layer is smoothly transitioned from 30-50 μm to 5-10 μm, thereby forming a precursor with a gradient porosity structure in the composite.

[0017] Preferably, in step S3, the accelerator voltage of the electron beam radiation is 180–350 keV, and the total radiation dose is 50–100 kGy. In step S4, the precision grinding step controls the surface roughness of the final product to be within the range of 0.4 to 0.8 μm.

[0018] By adopting the above technical solution, the surface chemical modification of the core-shell nanoparticles is carried out in advance to enhance their interfacial bonding force with the rubber matrix; at the same time, through the multi-layer co-extrusion technology integrating a programmable dynamic proportioning system, a gradient pore structure precursor with continuously varying sizes from large to small is precisely constructed at the microscale; combined with optimized electron beam curing parameters and the final precision grinding process, a comprehensive beneficial effect is achieved, which ensures that the performance of each functional component is maximized while further improving and reliably guaranteeing the mechanical properties, printing accuracy, and durability of the final product.

[0019] In summary, this application has the following beneficial effects: 1. Because this application adopts a synergistic auxiliary agent system that combines microcapsule self-healing agent and polymerization catalyst in the surface layer rubber, when microcracks are generated on the surface of the rubber blanket due to fatigue, the microcapsules will rupture and release the healing agent. The healing agent can polymerize in situ under the action of the catalyst to repair the damage, thus achieving the beneficial effect of actively inhibiting the propagation of fatigue cracks and significantly extending the overall service life of the rubber blanket.

[0020] 2. Since this application uses electron beam radiation curing technology to achieve integral molding, and combines reactive block copolymer surfactants to modify the pore walls, the electron beam curing forms strong covalent bonds between layers and at the interface, achieving seamless integration. At the same time, the reactive surfactants chemically anchor the pore structure walls to the rubber matrix, resulting in excellent resilience, anti-delamination ability, and structural stability against compression set.

[0021] 3. Since this application uses surface-functionalized core-shell nanoparticles with silica as the core and perfluoropolyether as the shell to reinforce the surface layer, the perfluoropolyether shell gives the rubber blanket surface excellent chemical inertness and low surface energy. At the same time, the nanoparticles are firmly anchored in the rubber matrix through covalent bonds, thus obtaining excellent wear resistance, resistance to ink cleaning agent solvent erosion and good ink release performance, thereby ensuring the long-term stability of the printed surface. Attached Figure Description

[0022] Figure 1 This application provides a flowchart of a method for preparing a highly elastic printing rubber blanket. Detailed Implementation

[0023] The present application will be further described in detail below with reference to the accompanying drawings and embodiments.

[0024] Technical concept: After being subjected to compression, mechanical friction, and chemical erosion by inks and cleaning agents, the surface layer of the printing blanket passively bears the damage and lacks any active repair mechanism. These micro-defects become stress concentration points, which continue to expand and converge in subsequent printing cycles, eventually leading to surface fatigue, cracking, and performance degradation.

[0025] Based on this discovery, the applicant aims to break away from the traditional design approach of passively bearing damage with rubber blankets and instead seek a technological path that can actively manage and repair damage. The applicant has conducted in-depth research on the damage mechanism of rubber blankets and found that the key to their end-of-life lies in the initiation and uncontrollable propagation of microcracks. Based on this, the applicant envisions that if the concept of biomimetic "self-healing" can be introduced into the rubber blanket material system, enabling it to repair itself in situ when damage occurs, it is hoped that its service life can be fundamentally extended.

[0026] Please refer to the appendix. Figure 1 ; Example 1, S1, Preparation of composite rubber compound: By weight, 50 parts of maleic anhydride-grafted ethylene propylene diene monomer (EPDM) rubber Mg-EPDM, 15 parts of core-shell nanoparticles prepared in Preparation Example 1 (pre-modified with KH-550 surface), 1 part of microcapsule self-healing agent prepared in Preparation Example 2, 0.05 parts of Grubbs catalyst, and 13 parts of multifunctional acrylate crosslinking agent TMPTA were mixed in an internal mixer at 40°C for 15 minutes to obtain a surface layer composite rubber compound.

[0027] Compressible layer composite compound: By weight, 50 parts of hydrogenated nitrile butadiene rubber (HNBR), a total of 60 parts of first crystalline polyethylene glycol PEG-1 with an average particle size of 40 μm and second crystalline polyethylene glycol PEG-2 with an average particle size of 8 μm, 2 parts of the reactive block copolymer surfactant prepared in Preparation Example 3, 3 parts of flake hexagonal boron nitride (h-BN), 5 parts of aluminum hydroxide (ATH), and 13 parts of TMPTA crosslinking agent are mixed in an internal mixer at 40°C for 15 minutes to obtain a compressible layer composite compound; S2. Integrated Composite: The surface layer composite material and the compressible layer composite material are bonded to a high-strength polyester fabric base through a multi-layer co-extrusion die integrating a programmable dynamic proportioning mixing system. Within a 0.5-second transition time, the particle size distribution of the sacrificial template agent used in the compressible layer smoothly transitions from being predominantly PEG-1 to being predominantly PEG-2, forming a multi-layer composite with a gradient structure. S3. Radiation curing: The multilayer composite is fed into an electron beam radiation device and cured in an integrated manner under the conditions of accelerator voltage of 180keV and total radiation dose of 50kGy to obtain a cured semi-finished product. S4. Post-processing and molding: The cured semi-finished product is placed in anhydrous ethanol at 50°C for solvent extraction for 2 hours to remove the PEG sacrificial template agent and form a gradient pore structure. After drying, the surface layer is precision ground to control the surface roughness (Ra) of the final product to 0.8μm, thus obtaining the final product.

[0028] Example 2: The preparation method in this example is basically the same as that in Example 1, except that the amount of each component and the range of process parameters are as follows: In step S1, the surface layer composite adhesive composition consists of: 75 parts Mg-EPDM, 20 parts core-shell nanoparticles, 3 parts microcapsules, 0.12 parts catalyst, and 15.5 parts TMPTA. The compressible layer composite adhesive composition consists of: 75 parts HNBR, 70 parts PEG template agent, 5 parts reactive surfactant, 6.5 parts h-BN, 10 parts ATH, and 15.5 parts TMPTA. In step S2, the gradient transition time is 1.0 second; In step S3, the accelerator voltage for electron beam radiation is 265 keV, and the total radiation dose is 75 kGy. In step S4, the precision grinding controls the surface roughness (Ra) to be 0.6 μm. Example

[0029] The preparation method in this embodiment is basically the same as that in Example 1, except that the amount of each component and the range of process parameters are as follows: In step S1, the surface layer composite adhesive composition consists of: 100 parts Mg-EPDM, 25 parts core-shell nanoparticles, 5 parts microcapsules, 0.2 parts catalyst, and 18 parts TMPTA. The compressible layer composite adhesive composition consists of: 100 parts HNBR, 80 parts PEG template agent, 8 parts reactive surfactant, 10 parts h-BN, 15 parts ATH, and 18 parts TMPTA. In step S2, the gradient transition time is 1.5 seconds; In step S3, the accelerator voltage for electron beam radiation is 350 keV, and the total radiation dose is 100 kGy. In step S4, the precision grinding controls the surface roughness (Ra) to be 0.4 μm.

[0030] Comparative Example 1: 100 parts of ordinary ethylene propylene diene monomer (EPDM) rubber and 40 parts of ordinary nano-silica were mixed to prepare a surface layer compound; 100 parts of nitrile butadiene rubber (NBR) and 10 parts of azodicarbonamide (AC foaming agent) were mixed to prepare a compressible layer compound. The two layers were laminated onto a fabric base by calendering, and then hot-pressed and vulcanized in a flat vulcanizing machine at 160°C and 15MPa for 20 minutes to form the final product.

[0031] Comparative Example 2: The preparation method of this comparative example is exactly the same as that of Example 2. The difference is that no microcapsule self-healing agent and Grubbs catalyst are added to the surface layer composite material in step S1. The missing weight is made up by Mg-EPDM rubber.

[0032] Comparative Example 3 was prepared in exactly the same way as in Example 2, except that no flake hexagonal boron nitride (h-BN) was added to the compressible composite rubber in step S1, and the missing weight was made up by HNBR rubber.

[0033] Comparative Example 4: The preparation method of this comparative example is exactly the same as that of Example 2. The difference is that in the compressible layer composite material of step S1, 5 parts of non-reactive conventional surfactant polyethylene glycol (400) monooleate are used to replace the reactive block copolymer surfactant in equal amounts.

[0034] Comparative Example 5: The preparation method of this comparative example is exactly the same as that of Example 2. The difference is that in the surface layer composite adhesive of step S1, 20 parts of ordinary nano-silica (particle size 40 nm) without surface functionalization are used to replace the core-shell nanoparticles prepared in Example 1 in equal amounts.

[0035] Comparative Example 6: The preparation method of this comparative example is basically the same as that of Example 2. The difference is that the curing method in step S3 is replaced by the traditional hot-press vulcanization process, that is, hot-press vulcanization for 20 minutes at 160°C and 15MPa, instead of electron beam radiation curing.

[0036] The rubber blanket samples prepared in Examples 1-3 and Comparative Examples 1-6 were subjected to performance testing according to the following methods.

[0037] Dynamic printing durability (10,000 cycles): On the IgtC1 printability tester, the printing pressure was set to 1.0 MPa and the speed to 300 m / min to simulate high-speed printing conditions. The cumulative number of printing cycles until visible macroscopic cracks appear on the surface or the dot gain exceeds 25% was used as the evaluation index.

[0038] Self-healing efficiency %: Using a Vickers hardness tester, a 2N load was applied to the sample surface to create a small indentation, introducing a microcrack. The sample was then left to stand at 40°C for 24 hours. The fracture toughness of the repaired area was tested using a nanoindenter and compared with the original fracture toughness of the undamaged area of ​​the same sample. Repair efficiency = (repaired toughness / original toughness) × 100%.

[0039] High-speed operation surface temperature rise (°C): A sinusoidal compressive strain of 10 Hz was applied to the sample on a Dynamic Mechanical Analyzer (DMA) and the operation was continued for 30 minutes. The highest temperature at the center of the rubber-fabric surface was measured using a high-precision infrared thermal imager, and the difference between this temperature and the ambient temperature of 25°C was recorded.

[0040] Compression set percentage: The test was conducted according to GB / T7759.1-2015 "Determination of compression set of vulcanized rubber or thermoplastic rubber under constant deformation", with test conditions of 70℃×22h.

[0041] Solvent resistance mass change rate %: According to GB / T1690-2010 "Test method for liquid resistance of vulcanized rubber or thermoplastic rubber", a 2cm×2cm sample is completely immersed in commercially available "Hyderborg" brand dampening solution, and after being immersed at a constant temperature of 40℃ for 72 hours, it is taken out, the surface liquid is wiped dry, its mass is weighed, and the mass change rate is calculated.

[0042] Pore ​​interface evaluation: The rubber sheet sample was fractured with liquid nitrogen, and the compressible layer section was taken. After gold sputtering, the interface between the pore wall and the rubber matrix was observed under a scanning electron microscope (SEM) to evaluate the degree of bonding.

[0043] Table 1: Overall Performance Test Results of Examples and Comparative Examples Test item Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Dynamic printing endurance (10,000 times) >800 >1000 >1200 <150 450 950 680 820 180 Self-repairing efficiency (%) 72 85 91 0 0 86 84 85 15 Surface temperature rise at high speed (°C) 12.5 9.8 7.5 28.6 9.9 25.1 9.7 9.8 10.1 Compression set (%) 8.5 6.2 4.8 21.3 6.5 6.1 15.5 6.4 6.3 Solvent resistance (mass change rate %) 2.5 1.8 1.2 9.5 1.9 1.8 1.9 8.1 2.0 Pore interface Good Excellent Excellent N / A Excellent Excellent Gaps exist Excellent Excellent As can be seen from Table 1: Examples 1-3 and Comparative Example 1: The high-elasticity printing blankets prepared in Examples 1, 2, and 3 of this application exhibit significantly better performance indicators than the product of Comparative Example 1, which uses related technologies, in terms of dynamic printing resistance, self-healing efficiency, thermal stability, and resistance to permanent deformation. This demonstrates the significant advancement of the overall technical solution of this application. As the content of each component and process parameters change from the lowest value in Example 1 to the highest value in Example 3 within the set range, the various performance characteristics of the cable show a steady upward trend.

[0044] As can be seen from Example 2 and Comparative Example 2, and Table 1, in the absence of microcapsule self-healing agent and catalyst, the self-healing efficiency of the sample is 0, and the dynamic printing durability drops sharply from more than 10 million cycles to 4.5 million cycles. This fully demonstrates that the self-healing system introduced in this application is the core technical means to actively inhibit fatigue crack propagation and fundamentally extend the service life of the rubber blanket.

[0045] As can be seen from Example 2 and Comparative Example 3, and in conjunction with Table 1, the surface temperature rise of the sample during high-speed operation increased sharply from 9.8℃ to 25.1℃ after the absence of plate-like hexagonal boron nitride. This is because plate-like hexagonal boron nitride constructs an efficient heat conduction path in the compressible layer, and its absence prevents the effective dissipation of hysteresis heat generated by the rubber blanket during high-speed operation, thus affecting performance stability. This demonstrates that plate-like hexagonal boron nitride is crucial for achieving excellent thermal management functions of the rubber blanket.

[0046] As can be seen from Example 2 and Comparative Example 4, and in conjunction with Table 1, when a non-reactive surfactant was used to replace the reactive block copolymer surfactant of this application, the compression set of the sample deteriorated from 6.2% to 15.5%, and SEM images showed obvious gaps at the interface between the pore walls and the matrix. This is because the acrylate end groups of the reactive surfactant can chemically bond with the rubber matrix during curing, firmly anchoring the pore structure, thereby greatly improving the structural stability and resilience of the compressible layer.

[0047] As can be seen from Example 2 and Comparative Example 6, and in conjunction with Table 1, when conventional high-temperature curing was used instead of electron beam radiation curing, the self-healing efficiency of the samples plummeted from 85% to 15%, and the dynamic printing durability also decreased sharply. This is because the high-temperature curing process can damage the heat-sensitive microcapsule wall material or cause premature leakage and failure of the core material. This proves that the low-temperature electron beam curing process used in this application is a key and necessary process guarantee for fully preserving the activity of each functional component and ensuring the realization of the synergistic effect of this invention.

[0048] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A highly elastic printing blanket, characterized in that, include: Maleic anhydride-grafted EPDM rubber for surface layers, core-shell nanoparticles, hydrogenated nitrile butadiene rubber for compressible layers, crystalline polyethylene glycol sacrificial template agents, and multifunctional acrylate crosslinking agents. And synergistic adjuvant systems containing the following components: Microcapsule self-healing agent, polymerization catalyst, reactive block copolymer surfactant, and plate-like hexagonal boron nitride.

2. The high-elasticity printing blanket according to claim 1, characterized in that, Includes the following weight combinations: For the surface layer, there are 50-100 parts of maleic anhydride-grafted EPDM rubber, 15-25 parts of core-shell nanoparticles, 50-100 parts of hydrogenated nitrile butadiene rubber for the compressible layer, 60-80 parts of crystalline polyethylene glycol sacrificial template agent, and 13-18 parts of multifunctional acrylate crosslinking agent. And synergistic adjuvant systems containing the following components: The microcapsule self-healing agent consists of 1-5 parts, the polymerization catalyst consists of 0.05-0.2 parts, the reactive block copolymer surfactant consists of 2-8 parts, and the flake-shaped hexagonal boron nitride consists of 3-10 parts. The microcapsule self-healing agent is a microcapsule with polyurethane or polyurea as the wall material and coated with a liquid healing agent; the polymerization catalyst is a solid-phase catalyst dispersed in a rubber matrix.

3. The high-elasticity printing blanket according to claim 2, characterized in that, The liquid healing agent is dicyclopentadiene; the polymerization catalyst is a Grubbs catalyst.

4. The high-elasticity printing blanket according to claim 1, characterized in that, The reactive block copolymer surfactant is an acrylate-terminated polyethylene glycol-block-polycaprolactone.

5. The high-elasticity printing blanket according to claim 1, characterized in that, The average diameter of the sheet-like hexagonal boron nitride is 1-5 μm, and it is distributed in the compressible layer.

6. The high-elasticity printing blanket according to claim 1, characterized in that, The core-shell nanoparticles are composite nanoparticles with spherical silica with a particle size of 30-50 nm as the core and perfluoropolyether as the shell.

7. The high-elasticity printing blanket according to claim 1, characterized in that, The crystalline polyethylene glycol sacrificial template agent is composed of a first crystalline polyethylene glycol with an average particle size of 30-50 μm and a second crystalline polyethylene glycol with an average particle size of 5-10 μm.

8. A method for preparing a high-elasticity printing blanket, applied to the high-elasticity printing blanket according to any one of claims 1-7, characterized in that, Includes the following steps: S1. Preparation of composite rubber compound: Maleic anhydride-grafted EPDM rubber, surface-functionalized core-shell nanoparticles, microcapsule self-healing agent, polymerization catalyst, and multifunctional acrylate crosslinking agent are mixed to obtain surface layer composite rubber compound; hydrogenated nitrile butadiene rubber, crystalline polyethylene glycol sacrificial template agent, reactive block copolymer surfactant, flake hexagonal boron nitride, and multifunctional acrylate crosslinking agent are mixed to obtain compressible layer composite rubber compound; S2, Integrated Composite: The surface layer composite material and the compressible layer composite material are composited onto the fabric base through multi-layer co-extrusion technology to form a multi-layer composite with a gradient structure; S3. Radiation curing: The multilayer composite is cured in an integrated manner by electron beam radiation to form chemical bonds between the layers, thereby obtaining a cured semi-finished product. S4. Post-processing molding: Solvent extraction is performed on the cured semi-finished product to remove the sacrificial template agent in the compressible layer, forming a gradient pore structure, and the surface layer is precisely ground to obtain the final product.

9. The method for preparing a high-elasticity printing blanket according to claim 8, characterized in that, In step S1, before preparing the surface layer composite adhesive, the core-shell nanoparticles are pretreated as follows: The surface of the material was chemically modified with γ-aminopropyltriethoxysilane to introduce active functional groups. In the preparation of compressible layer composite rubber, aluminum hydroxide or magnesium hydroxide is added as a flame retardant, and its dosage is 5 to 15 parts by weight of hydrogenated nitrile rubber. After completing the above steps, proceed to the following steps: In step S2, a multi-layer co-extrusion die head integrating a programmable dynamic proportioning mixing system is used to achieve the desired effect within a transition time of 0.5 to 1.5 seconds. The particle size distribution of the sacrificial template agent used in the compressible layer is smoothly transitioned from 30-50 μm to 5-10 μm, thereby forming a precursor with a gradient porosity structure in the composite.

10. The method for preparing a high-elasticity printing blanket according to claim 8, characterized in that, In step S3, the accelerator voltage of the electron beam radiation is 180–350 keV, and the total radiation dose is 50–100 kGy. In step S4, the precision grinding step controls the surface roughness of the final product to be within the range of 0.4 to 0.8 μm.

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