High-wear-resistance and high-elasticity EPDM (ethylene-propylene-diene monomer) sheet and preparation method thereof

Abstract

The invention relates to the technical field of EPDM sheets, and discloses a high-wear-resistance and high-elasticity EPDM sheet and a preparation method thereof.The EPDM sheet comprises the EPDM sheet body, the EPDM sheet body is composed of a surface layer, an elastic enhancement layer, a buffer layer, an enhancement skeleton layer, a bonding transition layer and a bottom layer, the bottom layer is arranged on the bottommost layer of the EPDM sheet body, the top of the bottom layer is fixedly connected with the bonding transition layer, and the bottom layer is arranged on the bottom layer of the EPDM sheet body. The top of the bonding transition layer is fixedly connected with a reinforcing framework layer, the top of the reinforcing framework layer is fixedly connected with a buffer layer, the top of the buffer layer is fixedly connected with an elastic reinforcing layer, and the top of the elastic reinforcing layer is fixedly connected with a surface layer. According to the high-wear-resistance and high-elasticity EPDM sheet and the preparation method thereof, through the innovative six-layer structural design, the characteristics of all layers of materials are fully exerted, the utilization rate of EPDM rubber and other raw materials is increased, the surface layer is made of the high-wear-resistance EPDM rubber composite material, the surface layer is matched with the special wear-resistance filler, and the external friction and scraping resistance of the sheet is remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of EPDM sheets, in particular to a high-wear-resistant and high-elasticity EPDM sheet and a preparation method thereof. Background Art

[0002] Traditional rubber sheets have exposed obvious defects in many application scenarios. In the industrial field, rubber products such as conveyor belts and seals often have insufficient wear resistance. During long-term friction with materials and mechanical pressure, the surface wears out quickly, resulting in a significant reduction in service life. According to statistics, the average service life of ordinary rubber conveyor belts in high-intensity working environments is only 6-8 months. Frequent replacement not only consumes a lot of manpower and material resources, but also seriously affects production efficiency.

[0003] With the increasing awareness of environmental protection and the popularization of the concept of sustainable development, the rubber material industry is facing huge challenges. On the one hand, a large amount of environmentally harmful additives are often used in the traditional rubber production process, and waste rubber products are difficult to degrade, causing long-term pollution to soil and water sources. On the other hand, in order to achieve efficient utilization of resources, it is necessary to develop new rubber materials to improve the recyclability and reuse rate of materials while ensuring high performance. In this context, the development of an EPDM sheet and its preparation method that can effectively integrate high wear resistance and high elasticity and has a green and environmentally friendly preparation process has become a key issue that the industry needs to solve urgently. Summary of the invention

[0004] The object of the present invention is to provide a highly wear-resistant and highly elastic EPDM sheet and a preparation method thereof, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions: a highly wear-resistant and highly elastic EPDM sheet, comprising an EPDM sheet, wherein the EPDM sheet is composed of a surface layer, an elastic reinforcement layer, a buffer layer, a reinforcement skeleton layer, a bonding transition layer and a bottom layer;

[0006] The bottom layer is arranged at the bottom layer of the EPDM sheet, the top of the bottom layer is fixedly connected with a bonding transition layer, the top of the bonding transition layer is fixedly connected with a reinforcing skeleton layer, the top of the reinforcing skeleton layer is fixedly connected with a buffer layer, the top of the buffer layer is fixedly connected with an elastic reinforcing layer, and the top of the elastic reinforcing layer is fixedly connected with a surface layer.

[0007] Preferably, the surface layer is composed of a highly wear-resistant EPDM rubber composite material, the elastic reinforcement layer is composed of a highly elastic EPDM raw rubber material, the buffer layer is composed of a foamed EPDM material, the bonding transition layer is composed of an EPDM rubber adhesive material with special functional groups, and the bottom layer is composed of an EPDM rubber material with an anti-slip agent added.

[0008] A preparation method of a highly wear-resistant and highly elastic EPDM sheet, comprising the following steps:

[0009] S1. Raw material preparation

[0010] According to the unique performance requirements of each layer, select the appropriate grade of EPDM raw rubber precisely. For the surface layer that bears the heavy responsibility of wear resistance, preferably choose the raw rubber with a higher molecular weight and rich ethylene content. Such raw rubber has a long molecular chain and good regularity, and can effectively resist wear by virtue of the closely arranged molecular structure when rubbing with the outside world frequently, effectively ensuring the high wear resistance of the surface layer. While for the elastic enhancement layer, focus on selecting the raw rubber with a low Mooney viscosity and a high degree of unsaturation;

[0011] Prepare all kinds of compounding agents comprehensively, including fillers (such as nano-silica, calcium carbonate, etc.), plasticizers (such as dioctyl phthalate), vulcanizing agents (typified by dicumyl peroxide), accelerators (such as dibenzothiazole disulfide), anti-aging agents (such as N-phenyl-N'-isopropyl-p-phenylenediamine), blowing agents (such as azodicarbonamide), anti-slip aids (such as rubber anti-slip agents) and fiber fabrics and other raw materials;

[0012] S2. Mixing of each layer of the EPDM sheet

[0013] (1) Mixing of the surface layer: Put the EPDM raw rubber into a Banbury mixer, first carry out plasticization to make it have good processing performance, and then add nano-silica, part of the plasticizer, anti-aging agent, vulcanizing agent, accelerator, etc. in sequence, and mix evenly at an appropriate temperature (about 120 - 150 °C) and rotation speed to make a highly wear-resistant mixed rubber, and then thin-pass and sheet out on a two-roll mill for standby;

[0014] (2) Mixing of the elastic enhancement layer: After plasticizing the selected EPDM raw rubber in a Banbury mixer, add a large amount of plasticizer, softening agent, an appropriate amount of anti-aging agent, vulcanizing agent and accelerator, control the mixing temperature at 110 - 140 °C, and mix thoroughly to obtain a highly elastic mixed rubber, and then sheet out on a two-roll mill;

[0015] (3) Mixing of the buffer layer: After plasticizing the EPDM raw rubber, add a blowing agent, blowing aid, filler, vulcanizing agent, accelerator, etc., and mix evenly at 100 - 130 °C to make a foamed mixed rubber. After sheet out on a two-roll mill, carry out pre-foaming treatment at a certain temperature (such as 70 - 90 °C) to make the blowing agent decompose initially to generate bubbles;

[0016] (4) Treatment of the reinforced skeleton layer: Carry out surface treatment on the fiber fabric, such as dipping, coating, etc., so that a layer of adhesive with good compatibility with EPDM rubber adheres to its surface to enhance the adhesion with the rubber. The treated fiber fabric is cut into the designed size for standby;

[0017] (5) Preparation of the bonding transition layer: Mix EPDM rubber containing special functional groups, vulcanizing agent, accelerator and appropriate plasticizer evenly on an open mill to make the mixed rubber for the bonding transition layer, and take out the sheet for standby;

[0018] (6) Mixing of the bottom layer: After plasticizing the EPDM raw rubber, add anti-slip additives, fillers, vulcanizing agent, accelerator, etc., and mix evenly at 120 - 150 °C to make the anti-slip mixed rubber, and take out the sheet through an open mill;

[0019] S3. Molding and compounding

[0020] On a molding die or professional molding equipment, lay each layer of sheet or material in an orderly manner in strict accordance with the specific order of the bottom layer, bonding transition layer, reinforcing skeleton layer, buffer layer, elastic reinforcing layer, and surface layer. When laying the bottom layer sheet, ensure that it is placed flat on the die or equipment with accurate positioning. Immediately afterwards, gently cover the bonding transition layer sheet on the bottom layer. During the operation, be highly focused to make the two layers fit closely together, avoiding any wrinkles or offsets. Subsequently, place the reinforcing skeleton layer, and carefully adjust the position of the fiber fabric to ensure its uniform distribution within the entire sheet area and full contact with the lower layer material;

[0021] Transfer the stacked materials smoothly to a hot press. The hot press is set at a temperature of 160 - 180 °C and the pressure is maintained at 10 - 15 MPa. Under this high-temperature and high-pressure environment, a series of complex physical and chemical reactions occur inside the sheet. The unsaturated double bonds in the rubber molecules start to initiate cross-linking reactions under the action of the vulcanizing agent and accelerator, and the molecular chains are interconnected to form a three-dimensional network structure, significantly improving the physical properties of the rubber;

[0022] S4. Trimming

[0023] For the sheet after hot pressing and forming, its edges often show phenomena such as overflow of glue or irregularity due to process characteristics. To ensure that the sheet size precisely meets the standard requirements, it is necessary to carry out trimming operations with the help of professional trimming equipment. Common trimming equipment includes punching machines and cutting machines, etc. When using a punching machine, by presetting a die adapted to the sheet specifications and using the powerful punching power of the equipment, it is possible to accurately and efficiently punch and remove the excess rubber at the edges of the sheet, making the edges neat. The cutting machine, relying on high-precision cutting tools, can carefully cut the edges of the sheet along the set size line, effectively removing the overflow glue and uneven parts. After being processed by such trimming equipment, the edges of the sheet are smooth and flat, and the size strictly meets the established standards, creating favorable conditions for the subsequent quality inspection and packaging of the sheet;

[0024] S5. Packaging

[0025] For the sheet after hot pressing and trimming, comprehensive and strict quality inspection work needs to be carried out. First, focus on the appearance of the sheet, carefully check its surface flatness to ensure there are no unevenness; at the same time, check for defects such as bubbles and impurities. Any minor surface defect may affect the overall performance of the sheet. Use a high-precision thickness gauge to measure the thickness of the sheet at multiple points to ensure its thickness is uniform and meets the design standards. In the hardness testing process, use a professional hardness tester and, according to the corresponding standard test method, accurately measure the hardness value of the sheet to evaluate the sheet's ability to resist local deformation. Use a tensile testing machine to conduct a tensile test on the sheet at a specified tensile rate to accurately obtain the tensile strength data of the sheet. This index directly reflects the sheet's ability to withstand tensile loads;

[0026] The qualified sheets after inspection are packaged according to customer requirements. Generally, plastic film or woven bags are used for packaging to prevent the sheets from being damaged, contaminated or aged during storage and transportation. The packaged sheets are stored in a dry, ventilated and cool warehouse, avoiding direct sunlight and high-temperature environments.

[0027] Preferably, in the above step S1, the low Mooney viscosity gives the raw rubber good fluidity, which is convenient for processing and forming. The high degree of unsaturation makes its molecular chain contain more active sites. In the subsequent vulcanization cross-linking process, it can form a more dense and elastic three-dimensional network structure, greatly promoting the improvement of elasticity and enabling the sheet to have excellent resilience.

[0028] Preferably, in the above step S1, strictly in accordance with the established formula, use high-precision weighing equipment to accurately weigh each raw material to ensure the accurate dosage of each raw material, laying a solid foundation for the full play of the synergistic effect of each component in the subsequent mixing process and preparing excellent performance layer materials.

[0029] Preferably, in the above step S2, the plasticizer improves the processing performance of the rubber and enhances the flexibility of the molecular chain; the anti-aging agent effectively resists the aging erosion of the rubber by external environmental factors; the vulcanizing agent and accelerator work together to lay the foundation for the subsequent vulcanization cross-linking reaction. After sufficient mixing, a high-abrasion-resistant mixed rubber is made. Subsequently, transfer this mixed rubber to an open mill, and through the thin-pass operation, further refine the internal structure of the rubber compound to make it more uniform. Finally, take out the sheet and store it properly for standby.

[0030] Preferably, in the above step S3, when placing the buffer layer, pay attention to maintaining the integrity of the foamed mixed rubber sheet, making it evenly cover the reinforced skeleton layer. The laying of the elastic enhancement layer and the surface layer also needs to be treated carefully to ensure that each layer fits tightly with the lower layer without any gaps. During the entire laying process, use professional tools (such as rollers) to moderately compact each layer to discharge the air between layers and prevent the generation of bubbles or gaps, laying a solid foundation for the subsequent hot pressing and forming process.

[0031] Preferably, in the above step S3, under the action of high temperature, the molecules between the layers of materials diffuse and penetrate each other, and the bonding transition layer plays a key role. Through chemical bonding and physical adsorption, etc., each layer is tightly fused into a whole. The hot pressing time is flexibly determined according to the thickness of the sheet and the vulcanization characteristics of the rubber, usually in the range of 10 - 30 minutes. For thinner sheets, the hot pressing time can be appropriately shortened; while for thicker sheets, the hot pressing time needs to be extended to ensure that the vulcanization reaction proceeds fully and the bonding between the layers is firm, and finally a high wear-resistant and high-elastic EPDM sheet with excellent performance and stable structure is obtained.

[0032] Preferably, in the above step S5, for the elasticity of the sheet, through a specific elasticity testing device, observe the ability of the sheet to return to its original state after being deformed by force, and quantitatively evaluate its elastic performance. The wear resistance detection relies on an abrasion testing machine to simulate the friction conditions of the sheet in actual use, and evaluate its wear resistance with parameters such as the abrasion amount. The anti-slip performance detection uses a friction coefficient tester to measure the friction coefficient between the sheet and a specific contact surface to judge whether its anti-slip effect meets the standard. For sheets that do not meet the quality standards after detection, organize professional personnel to deeply analyze the reasons. If the problem can be solved by secondary processing, adjusting process parameters, etc., then take corresponding improvement measures; if the defect is serious and cannot be repaired, then resolutely scrap it to prevent unqualified products from flowing into the market.

[0033] Compared with the prior art, the present invention provides a high wear-resistant and high-elastic EPDM sheet and its preparation method, having the following beneficial effects:

[0034] 1. The high wear-resistant and high-elastic EPDM sheet and its preparation method, through an innovative six-layer structure design, give full play to the characteristics of each layer of material, improve the utilization rate of EPDM rubber and other raw materials. The surface layer uses a high wear-resistant EPDM rubber composite material, combined with a special wear-resistant filler, significantly improving the ability of the sheet to resist external friction and scratching. When laying this EPDM sheet on the ground of an industrial production workshop, compared with ordinary rubber sheets, its wear-resistant life is extended by at least two times, effectively reducing the cost and time loss caused by frequent sheet replacement. The elastic enhancement layer, by selecting raw rubber with low Mooney viscosity and high unsaturation degree and optimizing the formula, endows the sheet with excellent elasticity. In the application scenario of the sports stadium floor, when athletes move on this sheet, they can obviously feel good resilience, effectively reducing sports fatigue and the risk of injury, providing a comfortable and safe experience for users.

[0035] 2. The highly wear-resistant and highly elastic EPDM sheet and its preparation method, the foamed EPDM material of the buffer layer can absorb and disperse the impact force, such as in the electronic equipment transportation packaging, it can effectively protect the precision electronic components from vibration damage. The reinforced skeleton layer greatly improves the tensile strength, tear strength and dimensional stability of the sheet, making it less likely to deform or damage when subjected to large external forces. It is suitable for building waterproofing, sealing and other fields with high requirements for structural strength. The anti-slip design of the bottom layer increases the friction between the sheet and the contact surface. When laid on wet outdoor trails or around swimming pools, it can effectively prevent pedestrians from slipping and ensure personal safety. It is widely used in a variety of places with strict requirements for anti-slip. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative labor:

[0037] Figure 1 This is a schematic diagram of the cross-sectional structure of the EPDM sheet of the present invention;

[0038] Figure 2 It is a flow chart of the preparation method of the present invention.

[0039] In the figure: 1, EPDM sheet; 11, surface layer; 12, elastic reinforcement layer; 13, buffer layer; 14, reinforcement skeleton layer; 15, bonding transition layer; 16, bottom layer. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] The present invention provides the following technical solutions:

[0043] Example 1

[0044] Combined with Figures 1 to 2 , a highly wear-resistant and highly elastic EPDM sheet, including the EPDM sheet 1, which is composed of a surface layer 11, an elastic reinforcement layer 12, a buffer layer 13, a reinforcement framework layer 14, an adhesive transition layer 15, and a bottom layer 16;

[0045] The bottom layer 16 is arranged at the bottommost layer of the EPDM sheet 1. The top of the bottom layer 16 is fixedly connected with the adhesive transition layer 15. The top of the adhesive transition layer 15 is fixedly connected with the reinforcement framework layer 14. The top of the reinforcement framework layer 14 is fixedly connected with the buffer layer 13. The top of the buffer layer 13 is fixedly connected with the elastic reinforcement layer 12. The top of the elastic reinforcement layer 12 is fixedly connected with the surface layer 11;

[0046] The surface layer 11 is composed of a highly wear-resistant EPDM rubber composite material. The elastic reinforcement layer 12 is composed of a highly elastic EPDM raw rubber material. The buffer layer 13 is composed of a foamed EPDM material. The adhesive transition layer 15 is composed of an EPDM rubber adhesive material with special functional groups. The bottom layer 16 is composed of an EPDM rubber material added with an anti-slip additive.

[0047] Example 2

[0048] Refer to Figures 1-2 , and on the basis of Example 1, a preparation method of a highly wear-resistant and highly elastic EPDM sheet is further obtained, including the following steps:

[0049] S1. Raw material preparation

[0050] According to the unique performance requirements of each layer, EPDM raw rubber of a suitable grade is accurately selected. For the surface layer that shoulders the heavy responsibility of wear resistance, raw rubber with a higher molecular weight and rich ethylene content is preferably selected. Such raw rubber has a long molecular chain and good regularity, and can effectively resist wear by virtue of its closely arranged molecular structure when rubbing with the outside world frequently, and effectively guarantee the high wear resistance of the surface layer. The elastic reinforcement layer focuses on selecting raw rubber with a low Mooney viscosity and a high degree of unsaturation;

[0051] All kinds of compounding agents are comprehensively prepared, covering raw materials such as fillers (such as nano-silica, calcium carbonate, etc.), plasticizers (such as dioctyl phthalate), vulcanizing agents (typified by dicumyl peroxide), accelerators (such as dibenzothiazole disulfide), anti-aging agents (such as N-phenyl-N'-isopropyl-p-phenylenediamine), blowing agents (such as azodicarbonamide), anti-slip additives (such as rubber anti-slip agents), and fiber fabrics;

[0052] S2. Mixing of each layer of the EPDM sheet

[0053] (1) Surface mixing: Put the EPDM raw rubber into the internal mixer, first carry out plasticizing to make it have good processing performance, and then add nano-silica, part of the plasticizer, antioxidant, vulcanizing agent, accelerator, etc. Mix evenly at an appropriate temperature (about 120 - 150 °C) and rotation speed to make a highly wear-resistant mixed rubber, and then thin-pass and sheet it on the open mill for standby;

[0054] (2) Elastic enhancement layer mixing: After plasticizing the selected EPDM raw rubber in the internal mixer, add a large amount of plasticizer, softening agent, appropriate antioxidant, vulcanizing agent and accelerator, control the mixing temperature at 110 - 140 °C, and mix thoroughly to obtain a highly elastic mixed rubber, and then sheet it on the open mill;

[0055] (3) Buffer layer mixing: After plasticizing the EPDM raw rubber, add a foaming agent, foaming aid, filler, vulcanizing agent, accelerator, etc., mix evenly at 100 - 130 °C to make a foamed mixed rubber, and after sheeting on the open mill, carry out pre-foaming treatment at a certain temperature (such as 70 - 90 °C) to make the foaming agent decompose initially to generate bubbles;

[0056] (4) Reinforced skeleton layer treatment: Carry out surface treatment on the fiber fabric, such as dipping, coating, etc., so that a layer of adhesive with good compatibility with EPDM rubber adheres to its surface to enhance the adhesion with the rubber. The treated fiber fabric is cut according to the designed size for standby;

[0057] (5) Bonding transition layer preparation: Mix the EPDM rubber containing special functional groups, vulcanizing agent, accelerator and appropriate plasticizer evenly on the open mill to make a mixed rubber for the bonding transition layer, and sheet it for standby;

[0058] (6) Bottom layer mixing: After plasticizing the EPDM raw rubber, add an anti-slip aid, filler, vulcanizing agent, accelerator, etc., mix evenly at 120 - 150 °C to make an anti-slip mixed rubber, and sheet it on the open mill;

[0059] S3. Molding and compounding

[0060] On the molding die or professional molding equipment, lay each layer of sheet or material in an orderly manner strictly according to the specific order of the bottom layer, bonding transition layer, reinforced skeleton layer, buffer layer, elastic enhancement layer, and surface layer. When laying the bottom layer sheet, ensure that it is placed flat on the die or equipment with accurate position. Immediately afterwards, gently cover the bonding transition layer sheet on the bottom layer. During the operation, be highly focused to make the two layers fit closely, avoiding any wrinkles or offsets. Then, place the reinforced skeleton layer, carefully adjust the position of the fiber fabric to ensure its uniform distribution within the entire sheet area and full contact with the lower layer material;

[0061] Transfer the material with completed lamination to a hot press steadily. The set temperature of the hot press is 160 - 180 °C, and the pressure is maintained at 10 - 15 MPa. In this high-temperature and high-pressure environment, a series of complex physical and chemical reactions occur inside the sheet. Under the action of vulcanizing agents and accelerators, the unsaturated double bonds in the rubber molecules start to initiate cross-linking reactions, and the molecular chains are interconnected to form a three-dimensional network structure, significantly improving the physical properties of the rubber;

[0062] S4. Trimming

[0063] For the sheet after hot pressing, its edges often show phenomena such as rubber overflow or an irregular state due to process characteristics. To ensure that the sheet size precisely meets the standard requirements, professional trimming equipment is needed to carry out the trimming operation. Common trimming equipment includes punching machines and cutting machines, etc. When using a punching machine, by presetting a mold adapted to the sheet specifications and using the powerful punching force of the equipment, the excess rubber at the edges of the sheet can be accurately and efficiently punched off, making the edges neat and uniform. The cutting machine, relying on high-precision cutting tools, can carefully cut the edges of the sheet along the set size line, effectively removing the rubber overflow and uneven parts. After being processed by such trimming equipment, the edges of the sheet are smooth and flat, and the size strictly meets the established standards, creating favorable conditions for the subsequent quality inspection and packaging of the sheet;

[0064] S5. Packaging treatment

[0065] For the sheet after hot pressing and trimming, a comprehensive and strict quality inspection work needs to be carried out. First, focus on the appearance of the sheet, carefully check its surface flatness to ensure there are no unevenness; at the same time, check for defects such as bubbles and impurities. Any minor surface defect may affect the overall performance of the sheet. Use a high-precision thickness gauge to measure the thickness of the sheet at multiple points to ensure that its thickness is uniform and meets the design standard. In the hardness testing link, with the help of a professional hardness tester and according to the corresponding standard test method, accurately measure the hardness value of the sheet to evaluate the ability of the sheet to resist local deformation. Use a tensile testing machine to conduct a tensile test on the sheet at a specified tensile rate to accurately obtain the tensile strength data of the sheet. This index directly reflects the ability of the sheet to withstand tensile loads;

[0066] The sheets that pass the inspection are packaged according to customer requirements. Generally, plastic films or woven bags are used for packaging to prevent the sheets from being damaged, contaminated or aged during storage and transportation. The packaged sheets are stored in a dry, ventilated and cool warehouse, avoiding direct sunlight and high-temperature environments.

[0067] In step S1, the low Mooney viscosity endows the raw rubber with good fluidity, facilitating processing and shaping. The high degree of unsaturation makes its molecular chains contain more active sites. During the subsequent vulcanization and cross-linking process, a denser and more elastic three-dimensional network structure can be formed, greatly promoting the improvement of elasticity and enabling the sheet to have excellent resilience.

[0068] In step S1, in strict accordance with the established formula, high-precision weighing equipment is used to accurately weigh each raw material to ensure the accurate dosage of each raw material, laying a solid foundation for the full play of the synergistic effect of each component in the subsequent mixing process and preparing high-performance materials for each layer.

[0069] In step S2, the plasticizer improves the processability of the rubber and enhances the flexibility of the molecular chains; the anti-aging agent effectively resists the aging erosion of the rubber by external environmental factors; the vulcanizing agent and the accelerator act synergistically to lay the foundation for the subsequent vulcanization and cross-linking reaction. After sufficient mixing, a high-abrasion-resistant mixed rubber is prepared. Subsequently, the mixed rubber is transferred to a two-roll mill, and through the thin-pass operation, the internal structure of the rubber compound is further refined to make it more uniform. Finally, the sheet is taken out and properly stored for later use.

[0070] In step S3, when placing the buffer layer, attention should be paid to maintaining the integrity of the foamed mixed rubber sheet, making it evenly cover the reinforcing skeleton layer. The laying of the elastic enhancement layer and the surface layer also needs to be treated carefully to ensure that each layer fits tightly against the lower layer without any gaps. During the entire laying process, professional tools (such as rollers) are needed to moderately compact each layer to expel the air between the layers and prevent the generation of bubbles or gaps, laying a solid foundation for the subsequent hot pressing and forming process.

[0071] In step S3, at high temperatures, the molecules between the interfaces of each layer of material diffuse and penetrate each other. The bonding transition layer plays a key role and tightly integrates each layer into a whole through chemical bonding and physical adsorption. The hot pressing time is flexibly determined according to the thickness of the sheet and the vulcanization characteristics of the rubber, usually within the range of 10 - 30 minutes. For thinner sheets, the hot pressing time can be appropriately shortened; while for thicker sheets, the hot pressing time needs to be extended to ensure sufficient vulcanization reaction and firm bonding between each layer, and finally a high-abrasion-resistant and high-elastic EPDM sheet with excellent performance and stable structure is prepared.

[0072] In step S5, regarding the elasticity of the sheet, through a specific elasticity testing device, observe the ability of the sheet to return to its original state after being deformed by force, and quantitatively evaluate its elastic properties. The wear resistance test relies on an abrasion testing machine to simulate the friction conditions of the sheet in actual use, and evaluates its wear resistance performance with parameters such as the amount of wear. The anti-slip performance test uses a friction coefficient tester to measure the friction coefficient between the sheet and a specific contact surface to determine whether its anti-slip effect meets the standard. For sheets that do not meet the quality standards after testing, organize professional personnel to deeply analyze the reasons. If the problem can be solved by secondary processing, adjusting process parameters, etc., then take corresponding improvement measures; if the defect is serious and cannot be repaired, then resolutely scrap it to prevent unqualified products from entering the market.

[0073] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of another identical element in the process, method, article or device including the said element.

Claims

1. A highly wear-resistant and highly elastic EPDM sheet, comprising an EPDM sheet (1), characterized in that: The EPDM sheet (1) is composed of a surface layer (11), an elastic reinforcement layer (12), a buffer layer (13), a reinforcement skeleton layer (14), a bonding transition layer (15) and a bottom layer (16); The bottom layer (16) is arranged at the bottom layer of the EPDM sheet (1), the top of the bottom layer (16) is fixedly connected to a bonding transition layer (15), the top of the bonding transition layer (15) is fixedly connected to a reinforcing skeleton layer (14), the top of the reinforcing skeleton layer (14) is fixedly connected to a buffer layer (13), the top of the buffer layer (13) is fixedly connected to an elastic reinforcing layer (12), and the top of the elastic reinforcing layer (12) is fixedly connected to a surface layer (11).

2. The highly wear-resistant and highly elastic EPDM sheet according to claim 1, characterized in that: The surface layer (11) is composed of a highly wear-resistant EPDM rubber composite material, the elastic reinforcement layer (12) is composed of a highly elastic EPDM raw rubber material, the buffer layer (13) is composed of a foamed EPDM material, the bonding transition layer (15) is composed of an EPDM rubber adhesive material with special functional groups, and the bottom layer (16) is composed of an EPDM rubber material to which an anti-slip agent is added.

3. A method for preparing a highly wear-resistant and highly elastic EPDM sheet according to claim 1, comprising the following steps: S1. Raw material preparation According to the unique performance requirements of each layer, the appropriate brand of EPDM raw rubber is accurately selected. For the surface layer that shoulders the heavy responsibility of wear resistance, raw rubber with high molecular weight and rich ethylene content is preferred. This type of raw rubber has a long molecular chain and good regularity. When it is frequently rubbed with the outside world, it can effectively resist wear with its tightly arranged molecular structure, effectively ensuring the high wear resistance of the surface layer. For the elastic reinforcement layer, raw rubber with low Mooney viscosity and high unsaturation degree is selected; Comprehensive preparation of various compounding agents, including fillers (such as nano-silica, calcium carbonate, etc.), plasticizers (such as dioctyl phthalate), vulcanizers (typically diisopropyl peroxide), accelerators (such as dibenzothiazole disulfide), antioxidants (such as N-phenyl-N'-isopropyl-p-phenylenediamine), foaming agents (such as azodicarbonamide), anti-slip agents (such as rubber anti-slip agents) and fiber fabrics and other raw materials; S2, EPDM sheet material mixing (1) Surface mixing: Put the EPDM raw rubber into the internal mixer, first plasticize it to make it have good processing properties, then add nano-silica, part of the plasticizer, antioxidant, vulcanizer, accelerator, etc., mix them evenly at an appropriate temperature (about 120-150°C) and speed to make a highly wear-resistant mixed rubber, then thin it on the open mixer and make sheets for use; (2) Mixing of elastic reinforcement layer: After plasticizing the selected EPDM raw rubber in an internal mixer, add a large amount of plasticizer, softener, appropriate amount of antioxidant, vulcanizer and accelerator, control the mixing temperature at 110-140°C, mix thoroughly to obtain a high elastic mixed rubber, and then produce sheets through an open mixer; (3) Buffer layer mixing: After plasticizing the EPDM raw rubber, add the foaming agent, foaming aid, filler, vulcanizer, accelerator, etc., mix them evenly at 100-130°C to make a foaming rubber mix. After the sheet is produced by the open mixer, it is pre-foamed at a certain temperature (such as 70-90°C) to make the foaming agent initially decompose and generate bubbles; (4) Strengthening skeleton layer treatment: Surface treatment of the fiber fabric is performed, such as by dipping, coating, etc., so that a layer of adhesive with good compatibility with EPDM rubber is attached to its surface to enhance the bonding force with the rubber. The treated fiber fabric is cut according to the designed size for use; (5) Preparation of bonding transition layer: EPDM rubber containing special functional groups, vulcanizing agent, accelerator and appropriate amount of plasticizer are mixed evenly on an open mill to prepare a mixed rubber for bonding transition layer, and the mixed rubber is produced for standby use; (6) Base mixing: After plasticizing the EPDM raw rubber, add anti-skid additives, fillers, vulcanizers, accelerators, etc., mix evenly at 120-150°C to make an anti-skid mixed rubber, and produce sheets through an open mixer; S3, Molding and Compounding On the forming mold or professional forming equipment, strictly follow the specific order of bottom layer, bonding transition layer, reinforcement skeleton layer, buffer layer, elastic reinforcement layer, and surface layer, and lay each layer of sheet or material in an orderly manner. When laying the bottom sheet, ensure that it is placed flat on the mold or equipment and the position is accurate. Then, gently cover the bonding transition layer sheet on the bottom layer. During the operation, you must be highly focused to make the two layers fit tightly and avoid any wrinkles or offsets. Then, place the reinforcement skeleton layer and carefully adjust the position of the fiber fabric to ensure that it is evenly distributed in the entire sheet area and fully in contact with the underlying material; The stacked materials are smoothly transferred to the hot press. The temperature of the hot press is set at 160-180℃ and the pressure is maintained at 10-15MPa. Under this high temperature and high pressure environment, a series of complex physical and chemical reactions occur inside the sheet. Under the action of the vulcanizer and accelerator, the unsaturated double bonds in the rubber molecules begin to initiate cross-linking reactions. The molecular chains are interconnected to form a three-dimensional network structure, which significantly improves the physical properties of the rubber. S4, trimming After hot pressing, the edges of the sheets often overflow with glue or appear irregular due to the process characteristics. In order to ensure that the size of the sheets accurately meets the standard requirements, professional trimming equipment is required to carry out trimming operations. Common trimming equipment includes punching machines and cutting machines. When using punching machines, by presetting molds that are compatible with the sheet specifications and using the powerful stamping power of the equipment, the excess rubber on the edge of the sheet can be accurately and efficiently punched out to make the edges neat and uniform. The cutting machine can use high-precision cutting tools to carefully cut the edge of the sheet along the set size line, effectively removing the overflow of glue and irregular parts. After being processed by such trimming equipment, the edge of the sheet can be flat and smooth, and the size strictly meets the established standards, creating favorable conditions for subsequent sheet quality inspection and packaging. S5. Packaging For the sheets after hot pressing and trimming, comprehensive and strict quality inspection is required. First of all, pay attention to the appearance of the sheets, carefully check the surface flatness to ensure that there are no bumps and unevenness; at the same time, check whether there are defects such as bubbles and impurities. Any tiny surface defects may affect the overall performance of the sheets. Use a high-precision thickness gauge to measure the thickness of the sheets at multiple points to ensure that the thickness is uniform and meets the design standards. In the hardness testing stage, with the help of a professional hardness tester, according to the corresponding standard test method, the hardness value of the sheet is accurately measured to evaluate the ability of the sheet to resist local deformation. Use a tensile testing machine to perform a tensile test on the sheet at the specified tensile rate to accurately obtain the tensile strength data of the sheet. This indicator directly reflects the ability of the sheet to withstand tensile loads; The qualified sheets are packaged according to customer needs, generally in plastic film or woven bags to prevent the sheets from being damaged, contaminated or aged during storage and transportation. The packaged sheets are stored in a dry, ventilated and cool warehouse to avoid direct sunlight and high temperature environment.

4. The method for preparing a highly wear-resistant and highly elastic EPDM sheet according to claim 1, characterized in that: In the above step S1, the low Mooney viscosity gives the raw rubber good fluidity, which is easy to process and shape. The high degree of unsaturation makes its molecular chain contain more active sites. In the subsequent vulcanization and cross-linking process, it can form a more dense and elastic three-dimensional network structure, which greatly promotes the improvement of elasticity and makes the sheet have excellent resilience.

5. The method for preparing a highly wear-resistant and highly elastic EPDM sheet according to claim 1, characterized in that: In the above step S1, each raw material is accurately weighed using high-precision weighing equipment in strict accordance with the established formula to ensure the precise amount of each raw material, so as to lay a solid foundation for the synergistic effect of each component in the subsequent mixing process and prepare each layer of material with excellent performance.

6. The method for preparing a highly wear-resistant and highly elastic EPDM sheet according to claim 5, characterized in that: In the above step S2, the plasticizer improves the processing properties of the rubber and enhances the flexibility of the molecular chain; the antioxidant effectively resists the aging erosion of the rubber by external environmental factors; the vulcanizer and the accelerator work synergistically to lay the foundation for the subsequent vulcanization and cross-linking reaction. After sufficient mixing, a highly wear-resistant mixed rubber is prepared. Subsequently, the mixed rubber is transferred to an open mixing mill, and through a thin-pass operation, the internal structure of the rubber is further refined to make it more uniform, and finally the sheets are produced and properly stored for later use.

7. The method for preparing a highly wear-resistant and highly elastic EPDM sheet according to claim 5, characterized in that: In the above step S3, when placing the buffer layer, care should be taken to maintain the integrity of the foamed mixed rubber sheet so that it is evenly covered on the reinforced skeleton layer. The laying of the elastic reinforcement layer and the surface layer also needs to be treated with caution to ensure that each layer fits tightly to the lower layer without leaving any gaps. During the entire laying process, professional tools (such as rollers) are required to appropriately compact each layer to expel the air between the layers and prevent the generation of bubbles or gaps, thereby laying a solid foundation for the subsequent hot pressing molding process.

8. The method for preparing a highly wear-resistant and highly elastic EPDM sheet according to claim 1, characterized in that: In the above step S3, under the action of high temperature, the interfaces between the layers of materials diffuse and penetrate each other, and the bonding transition layer plays a key role. Through chemical bonding and physical adsorption, the layers are tightly integrated into a whole. The hot pressing time is flexibly determined according to the thickness of the sheet and the vulcanization characteristics of the rubber, usually in the range of 10-30 minutes. For thinner sheets, the hot pressing time can be appropriately shortened; while for thicker sheets, the hot pressing time needs to be extended to ensure that the vulcanization reaction is fully carried out and the layers are firmly bonded, so as to finally obtain a high-wear-resistant and high-elastic EPDM sheet with excellent performance and stable structure.

9. The method for preparing a highly wear-resistant and highly elastic EPDM sheet according to claim 5, characterized in that: In the above step S5, for the elasticity of the sheet, a specific elasticity testing device is used to observe the ability of the sheet to recover to its original shape after being deformed by force, and its elastic performance is quantitatively evaluated. The wear resistance test relies on a wear testing machine to simulate the friction conditions of the sheet in actual use, and its wear resistance is evaluated by parameters such as wear amount. The anti-slip performance test uses a friction coefficient tester to measure the friction coefficient between the sheet and a specific contact surface to determine whether its anti-slip effect meets the standard. For sheets that do not meet the quality standards after testing, professional personnel are organized to conduct in-depth analysis of the reasons. If the problem can be solved by secondary processing, adjusting process parameters, etc., corresponding improvement measures will be taken; if the defect is serious and cannot be repaired, it will be decisively scrapped to prevent unqualified products from entering the market.

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