Adhesive-free compound forming method

Abstract

The invention relates to the technical field of material forming, in particular to an adhesive-free compound forming method which comprises the following specific steps: S1, mold cleaning; s2, cutting is carried out; s3, laying a rubber layer and an adhesive layer: sequentially laying the adhesive layer and the rubber layer on the surface of the plastic film; s4, checking a rubber layer and a rubber layer; s5, preforming by a pressing machine; s6, curing pretreatment is carried out; s7, curing and forming; and S8, demolding is conducted. According to the elastic rubber supporting pad, emission of volatile organic compounds is reduced without using a traditional adhesive, the requirement of modern green manufacturing is met, meanwhile, the adhesive layer is adopted to replace the adhesive for coating, the adhesive performance of the elastic rubber supporting pad is improved, the production process is simplified, and the labor cost and the time cost are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of material molding, and in particular to an adhesive-free compound molding method. Background Art

[0002] For the bonding of rubber and plastic film, in order to achieve excellent bonding strength, hot adhesives are generally used for bonding. However, this type of bonding process is relatively complicated, has high requirements on the storage environment and uniformity of the adhesive, and causes great pollution to the environment, making it unsuitable for long-term use.

[0003] Publication No.: CN105643947A proposed an "adapter molding process method" that uses hard polyurethane foam as the base layer and sponge stirring as the buffer layer. Due to the long storage period, the sponge rubber sheet is prone to permanent deformation under long-term pressure, which makes the overall adaptation layer function ineffective and loses its buffering capacity. At the same time, the sponge rubber sheet and polyurethane are bonded with solvent-based rubber adhesives, which have poor adhesive bonding technology and are prone to high-temperature bulging on the surface of the adaptation layer, affecting the product's service life.

[0004] Publication No.: CN112729007A proposes "an adapter and its molding process method, and a launch device", which uses a rubber layer as a bearing base layer and a polytetrafluoroethylene film and a surface foam layer as a buffer layer. This molding method has a complex molding process. During the foam molding process of the polytetrafluoroethylene film surface, wrinkles or white spots are easily formed on the surface of the polytetrafluoroethylene film, which seriously affects the product quality. In addition, the polytetrafluoroethylene foam layer uses epoxy adhesive, which has poor high temperature resistance and high environmental pollution, and is not suitable for batch trial production of adapter products.

[0005] Publication No.: CN103602288A proposes "Rubber solid adhesive and its preparation method and application". The rubber solid adhesive is used to bond untreated polyester filaments and nylon in the production process of fire hoses. It has high bonding strength and is superior to other hot melt adhesives in terms of heat resistance and scalding resistance, and the bonding is stable. However, this adhesive is not suitable for bonding plastics and rubbers, and cannot solve the problem of poor bonding performance. Moreover, as a liquid adhesive, the production efficiency is low.

[0006] Therefore, the adhesive used for bonding rubber and plastic film in the prior art has the problems of poor bonding performance, long production time, high production cost, large environmental pollution caused by volatile organic compounds, and unsuitability for long-term use. It is urgent to propose a composite molding process with lower cost and simpler molding process to solve the problems of poor bonding performance of rubber and plastic film products, long production time, high production cost, and large environmental pollution caused by volatile organic compounds. Summary of the invention

[0007] In view of this, the present invention aims to propose an adhesive-free compounding molding method to solve the problems of poor bonding performance of the product after rubber and plastic film, long production time, high production cost, and greater environmental pollution caused by volatile organic compounds.

[0008] The adhesive-free composite molding process of the present invention comprises the following steps: surface treatment of the plastic film; surface treatment of the adhesive layer; surface treatment of the rubber layer; and adhesive-free composite molding between the rubber layer, the adhesive layer and the plastic film. The solution is proposed by the inventor through creative labor and a large number of experiments. The solid adhesive layer is used to replace the existing adhesive. The thickness of the adhesive layer is controlled in the range of 0.58 mm to 0.64 mm, which greatly improves the bonding ability between the rubber layer and the plastic film, breaks the mindset of those skilled in the art, and solves the problem of poor bonding performance of the product after the rubber and the plastic film in the prior art.

[0009] In addition, the present invention has the advantages of low environmental pollution, simple molding process, short processing time, low production cost, light weight, high compression resistance and shock absorption. The elastic rubber support pad has better low heat generation and bending resistance than the polyurethane support pad, which effectively improves the life of the elastic support pad.

[0010] The technical solution of the present invention is achieved in this way: The present invention discloses an adhesive-free compounding and molding method, comprising the following specific steps: S1: Mould cleaning; S2: Cutting: the plastic film is cut to a set size using tool A, and the rubber layer and glue layer are cut to a set size using tool B, wherein the thickness of the glue layer ranges from 0.58 to 0.64 mm; S3: Laying the rubber layer and the glue layer, laying the glue layer and the rubber layer in sequence on the surface of the plastic film, and the distance between the rubber layer and the glue layer and the edge of the plastic film is 2-8 mm; S4: inspecting the rubber layer and the glue layer, and cutting open the bulges or bubbles on the surface of the rubber layer and the glue layer to remove impurities; S5: Preforming by press, after the adhesive layer is laid, it is placed in the press for more than 20 minutes and then taken out; S6: before curing begins, the plastic film attached to the rubber layer and the glue layer is placed in the middle of the mold, and the distance between the plastic film and the edge of the mold cavity is 2-6 mm; S7: After the mold is installed, slowly close the mold, preheat for 1-6 minutes, close the mold and maintain pressure. During this period, observe whether the mold is abnormal, and then adjust the oven curing temperature to 100-200℃ and the curing time to 30-50 minutes; S8: Demolding. After curing is completed, the product is completely removed from the mold to obtain a high-quality elastomer support pad material.

[0011] Furthermore, in step S2, the plastic film is one of a polyester film, a polyethylene film, a polypropylene film and a polytetrafluoroethylene film, and the plastic film is stretched by pultrusion or curling.

[0012] Furthermore, the plastic film is cut to a set size using A tooling, the surface of the plastic film needs to be treated with sodium naphthalene, and the thickness is between 0.4 mm and 0.6 mm.

[0013] Furthermore, the adhesive layer is a kind of chloroprene rubber or brominated butyl rubber, and the adhesive layer is processed by a precision calender, and bubbles, wrinkles and other defects are not allowed on the surface. After being manufactured, it is cut to a set size using a B tooling and rolled up for storage.

[0014] Furthermore, the steps for preparing the adhesive layer are as follows: ST1: The rubber type of the rubber layer is chloroprene rubber, and the fillers used include carbon black, white carbon black, tackifier, accelerator CZ and sulfur. The ratio is 50-100 parts of chloroprene rubber, 20-60 parts of carbon black, 10-30 parts of white carbon black, 0-30 parts of tackifier, 0-5 parts of accelerator CZ and 0-5 parts of sulfur; ST2: Use internal mixer and open mixer for mixing and molding, the speed is 35 / min, the mixing temperature is 70℃, and the debinding temperature does not exceed 120℃; ST3: After refining and molding, the mixed rubber is sent to a four-roll calender for compression molding. The speed ratio of AB and BC rollers is controlled at 0.9, the speed ratio of CD roller is controlled at 1, the distance between AB rollers is controlled at 0.7mm, the distance between BC rollers is controlled at 0.55mm, and the distance between CD rollers is controlled at 0.8mm. The total thickness of the film is controlled between 0.58 and 0.64mm and rolled into shape; ST4: The film produced in step ST3 is cut into a set size using tool B to obtain the adhesive layer.

[0015] Furthermore, in step S2, the rubber layer is one or more of natural rubber, styrene-butadiene rubber, EPDM rubber, and nitrile rubber, and is refined using an open mixing mill. The thickness is controlled at 3.8-4.2 mm, and bubbles, wrinkles, and other defects are not allowed on the surface. The rubber layer is cut to a set size using a B tool.

[0016] Furthermore, in step S2, the length and width dimensions of tooling A are 300 mm×200 mm, and the length and width dimensions of tooling B are 290 mm×190 mm.

[0017] Furthermore, in step S5, the press is a flat-plate vulcanizing press with a specification of 200t, 300t or 400t.

[0018] Furthermore, in step S7, the oven is 2.3 m high and 1.5 m wide, and the oven temperature ranges from 0 to 200°C.

[0019] Furthermore, the method further includes step S9, cutting the elastomeric support pad material in S8 into three samples each with a length of 200 mm, a width of 25 mm, and a thickness of 5 mm, placing the samples in a universal tensile testing machine, and testing the 180° peel strength of the samples.

[0020] The preparation steps of a conventional elastomer support pad are as follows: S1: mold cleaning; S2: cutting the plastic film into appropriate size according to tooling A, and cutting the rubber layer into appropriate size using tooling B; S3: using a 1.5-inch brush, dipped in a small amount of detergent, to clean the surface of the sodium naphthalene layer of the plastic film, ensuring that there are no other impurities on the surface of the plastic film; S4: using a 1.5-inch brush, dipped in a small amount of Chemlock, brushing one side of the sodium naphthalene treatment layer of the plastic film, ensuring that the adhesive is evenly applied; S5: laying the rubber layer; S6: preforming on a press; S7: curing and molding; S8: demolding.

[0021] Using Chemlok to bond plastic film and rubber layer is a common method in this field. Its bonding performance exceeds the bonding strength between rubber and plastic film. Therefore, rubber is not used to replace Chemlok to bond plastic film in conventional selection to achieve improved bonding performance.

[0022] At the same time, the process of brushing Chemlock is time-consuming and has high requirements. Taking a 500×500mm support pad as an example, the adhesive thickness range is required to be between ±0.02mm. Whether it is manual or operation, it is time-consuming and difficult to meet the requirements. In this process, the weight of Chemlock is required to be around 0.1kg, domestic Chemlock is 80 yuan / kg, imported Chemlock is 160 yuan / kg, and the most expensive Chemlock reaches 320 yuan / kg. The cost of the adhesive layer used in the present invention is only 15 yuan / kg, which is much lower than the cost of Chemlock, and the finished adhesive layer is used for molding, the production time is significantly shortened, and the occurrence of uneven coating that may occur when applying adhesive is avoided, which helps to improve product quality.

[0023] Compared with the prior art, the adhesive-free compounding molding method of the present invention has the following advantages: The present invention reduces the emission of volatile organic compounds by not using traditional adhesives through this molding method, meets the requirements of modern green manufacturing, has low environmental pollution, and saves the cost of purchasing and applying adhesives. At the same time, the plastic film and the rubber layer are bonded using an adhesive layer, thereby improving the bonding performance of the elastic rubber support pad.

[0024] The present invention simplifies the production process and reduces the manpower and time costs by using a glue layer instead of adhesive coating. Since no additional adhesive coating and drying time are required, the entire production cycle is shortened and the overall efficiency of the production line is improved.

[0025] The elastic rubber support pad of the present invention has the advantages of light weight, high compression resistance and shock absorption, and has better low heat generation and bending resistance than the polyurethane support pad, which can effectively increase the service life of the elastic support pad. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings: Figure 1 It is a schematic diagram of the structure of the elastomer support pad of the present invention.

[0027] Description of reference numerals: 1. Plastic film; 2. Adhesive layer; 3. Rubber layer. DETAILED DESCRIPTION

[0028] In order to make the technical means, objectives and effects of the present invention easy to understand, the embodiments of the present invention are described in detail below with reference to specific drawings.

[0029] It should be noted that all the terms used in the present invention to indicate directionality and position, such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "inside", "outside", "top", "lower", "lateral", "longitudinal", "center", etc., are only used to explain the relative positional relationship and connection status between the components in a certain state, and are only for the convenience of describing the present invention, rather than requiring the present invention to be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features.

[0030] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0032] Compounding and Molding refers to the process of mixing and compounding multiple raw materials and processing them into a specific shape. This process is widely used in industries such as rubber, plastics, and composite materials in order to produce products with specific properties and uses.

[0033] Practical tests show that the tensile shear strength of natural rubber and polytetrafluoroethylene (PTFE) membranes bonded using high-performance adhesives such as Chemlok is usually between 1 and 3 MPa. For flexible materials, the peel strength may vary within the range of 0.5 to 2 N / mm.

[0034] The specific steps for preparing a conventional elastomer support pad are as follows: S1: Mold cleaning: Use a mold cleaning agent to clean the mold. After cleaning the mold surface, use a clean gauze to apply a release agent to the mold surface. S2: Cutting: Cut the plastic film into appropriate sizes according to tooling A, and cut the rubber layer into appropriate sizes using tooling B. S3: Cleaning. Use a 1.5-inch brush, dip a small amount of detergent, and clean the surface of the sodium naphthalene layer of the plastic film to ensure that there are no other impurities on the surface of the plastic film. After standing for 5 minutes, set aside. S4: Glue brushing: Use a 1.5-inch brush, dip a small amount of Chemlock, and brush one side of the sodium naphthalene treatment layer of the plastic film to ensure that the adhesive is evenly applied and no missing brushing is allowed. S5: Laying the rubber layer: Lay the rubber layer on the surface of the plastic film. The distance between the rubber layer and the four ends of the plastic film is 5 mm. S6: Press preforming: After the glue layer is laid, place it in the press and press for more than 20 minutes before taking it out. S7: Before curing, place the plastic film with the rubber layer in the middle of the mold, and the distance between the plastic film and the four ends of the mold cavity should be 2-4mm. S8: After the mold is installed, slowly close the mold, preheat for 2-3 minutes, close the mold and keep the pressure, observe whether the mold is abnormal, and then adjust the curing temperature to 150℃ and the curing pressure to 40 minutes. S9: Demolding, after curing, remove the product completely from the mold to obtain high-quality elastomer support pad material.

[0035] The present invention discloses an adhesive-free compounding and molding method, comprising the following specific steps: S1: Mould cleaning; S2: Cutting: the plastic film 1 is cut to a set size using tool A, and the rubber layer 3 and the rubber layer 2 are cut to a set size using tool B; S3: Laying rubber layer 3 and rubber layer 2, laying rubber layer 2 and rubber layer 3 on the surface of plastic film 1 in sequence, with the distance between rubber layer 3 and rubber layer 2 and the edge of plastic film 1 being 2-8 mm; S4: Check the rubber layer 3 and the rubber layer 2, and cut open the bulges or bubbles on the surface of the rubber layer 3 and the rubber layer 2 to remove impurities; S5: Pre-forming in a press, after the adhesive layer 2 is laid, it is placed in a press and pressed for more than 20 minutes before being taken out; S6: Before curing begins, the plastic film 1 attached to the rubber layer 3 and the adhesive layer 2 is placed in the middle of the mold, and the distance between the plastic film 1 and the edge of the mold cavity is 2-6 mm; S7: After the mold is installed, slowly close the mold, preheat for 1-6 minutes, close the mold and maintain pressure. During this period, observe whether the mold is abnormal, and then adjust the curing temperature to 100-200℃ and the curing time to 30-50 minutes; S8: Demolding. After curing is completed, the product is completely removed from the mold to obtain a high-quality elastomer support pad material.

[0036] By precisely controlling the laying and pressing process of each layer of material, the close bonding between the plastic film 1, the adhesive layer 2 and the rubber layer 3 is ensured, thereby improving the bonding strength of the overall structure. Then, after the rubber layer 3 and the adhesive layer 2 are laid, they are inspected, and bulges or bubbles are treated with a utility knife and surface impurities are removed to ensure that there are no defects inside the finished product, thereby improving the reliability and durability of the product. After that, the temperature, time and pressure parameters are strictly controlled during the preforming and curing process of the press to ensure the dimensional accuracy and surface finish of the elastomer support pad material.

[0037] This setting does not use traditional adhesives, reduces the emission of volatile organic compounds (VOCs), meets the requirements of modern green manufacturing, saves the cost of purchasing and applying adhesives, simplifies the production process, reduces labor and time costs, and because no additional adhesive coating and drying time are required, the entire production cycle is shortened, improving the overall efficiency of the production line.

[0038] Specifically, in step S1, the mold material may be metal, pad cloth or other fiber-reinforced composite materials.

[0039] Metal molds have good thermal conductivity and can transfer heat quickly and evenly, ensuring uniform temperature distribution during the curing process. They are also sturdy and durable and can withstand the pressing and curing process under high pressure and high temperature conditions. They are suitable for mass production. At the same time, they can achieve very high dimensional accuracy through precision machining, ensuring the consistency and high quality of the finished product.

[0040] The cost of cloth molds is usually lower than that of metal molds, which is especially economical for small batches or trial products. Molds of different shapes and sizes can be quickly customized according to specific needs, shortening the development cycle.

[0041] Fiber-reinforced composite materials combine the advantages of high strength and low density, making the mold both strong and light. By selecting the appropriate matrix resin and reinforcing fiber, excellent mechanical properties such as tensile strength and flexural modulus can be obtained to meet specific application requirements.

[0042] This setting can significantly improve the effect of the compound molding process by rationally selecting the mold material and combining it with appropriate cleaning and release agent treatment, ensuring high quality and efficient production of the final product.

[0043] Specifically, in step S2, the plastic film 1 is the friction-reducing material of the elastic support pad, and the plastic film 1 can be a polyester film, a polyethylene film, a polypropylene film, a polytetrafluoroethylene film, etc. The plastic film 1 is stretched by pultrusion, curling, etc.

[0044] Polyester film has good tensile strength and abrasion resistance, and is suitable for applications that require greater mechanical stress. It can maintain stable dimensions and is not easily deformed even in an environment with large temperature changes.

[0045] Polyethylene film has good flexibility and ductility, can adapt well to complex shapes and bending requirements, has natural waterproof properties, and is suitable for use in humid or underwater environments.

[0046] Polypropylene film combines high strength and rigidity, suitable for applications requiring certain structural support, and has excellent electrical insulation properties, suitable for electronic equipment and electrical products.

[0047] PTFE membrane is known for its extremely low coefficient of friction, making it very suitable for use as an anti-friction material to reduce wear between moving parts. It can be used for a long time at very high temperatures and is suitable for applications in extreme environments.

[0048] This setting can optimize the production process while ensuring product performance and meet the needs of different application scenarios by reasonably selecting the material of the plastic film 1 and combining it with appropriate processing methods such as pultrusion and curling.

[0049] Specifically, the plastic film 1 is cut into a suitable size according to tooling A, its surface needs to be treated with sodium naphthalene, and its thickness is between 0.4 mm and 0.6 mm.

[0050] The plastic film 1 is precisely cut according to the A tool to ensure that it fits perfectly with the rubber layer 3 and the rubber layer 2 laid subsequently, avoiding poor bonding or material waste caused by size mismatch. The standardized cutting size simplifies the production process, reduces the time of manual adjustment, and improves the overall production efficiency. Sodium naphthalene treatment is a chemical treatment method. By dissolving metallic sodium in a naphthalene solution and then applying it to the plastic surface, the polarity and surface energy of the plastic surface can be significantly improved. After sodium naphthalene treatment, the surface of the plastic film 1 is more likely to form a strong bond with other materials such as the rubber layer 3, and the bonding force between the interfaces is enhanced. The appropriate thickness range provides sufficient mechanical strength and flexibility, and is neither easy to break nor too soft to affect the molding effect. Within this thickness range, the plastic film 1 can effectively transfer heat during the curing process and evenly distribute internal stress to prevent local overheating or stress concentration. 0.4mm to 0.6mm is a relatively ideal thickness range, which can meet the performance requirements of most applications without increasing too much cost. The plastic film 1 within this thickness range has good processability and is convenient for drawing operations such as pultrusion and curling. At the same time, it will not cause processing difficulties due to being too thin. The moderate thickness helps to maintain shape stability and reduce the possibility of deformation during high-temperature curing.

[0051] Preferably, the surface dyne value of the plastic film 1 after being treated with a sodium naphthalene layer is above 50.

[0052] Specifically, in step S2, the adhesive layer 2 is a tackifying material of the elastic support pad, and the adhesive layer 2 may be chloroprene rubber, brominated butyl rubber, or the like.

[0053] Neoprene has a wide range of bonding capabilities and can form strong bonds with a variety of materials including metals, plastics, wood, etc. It has good resistance to UV rays, ozone and other environmental factors and is suitable for outdoor use.

[0054] Bromobutyl rubber forms high-strength bonds with various substrates such as metal, glass, plastic, etc., and is particularly suitable for applications requiring high sealing properties. It is known for its extremely low gas permeability and is particularly suitable for applications requiring sealing properties. It has excellent thermal stability and oxidation resistance, and can still maintain good physical properties after long-term use.

[0055] By selecting appropriate rubber materials, the plastic film 1 and the rubber layer 3 are firmly bonded to each other, thereby improving the stability of the entire structure.

[0056] Specifically, the adhesive layer 2 is rolled using a precision calender, and the thickness is controlled between 0.58 mm and 0.64 mm. No bubbles, wrinkles or other defects are allowed on the surface. The B tooling is used to cut the adhesive layer to an appropriate size, and the adhesive layer is rolled up for storage.

[0057] The precision calender can accurately control the thickness of the adhesive layer 2 between 0.58mm and 0.64mm, ensuring that the thickness of each adhesive layer 2 is consistent, avoiding differences in bonding strength caused by uneven thickness. Through precision calendering, bubbles, wrinkles and other surface defects can be effectively eliminated, providing a smooth and flat surface, which is very important for subsequent bonding operations. The thickness of the adhesive layer 2 is controlled between 0.58mm and 0.64mm. If the thickness is too thick, the entire bonding is equivalent to the bonding of the adhesive layer 2 and the plastic, the product forming quality is not good, the adhesive layer 2 is prone to bubbling, and the thickness is uneven; if the thickness is too thin, the bonding process is equivalent to the rubber directly bonding the plastic. After bonding, the product has insufficient bonding strength and it is difficult to meet the quality requirements of the product. A smooth and defect-free surface can better contact with the plastic film 1 or other materials to form a firm bonding interface, avoiding bonding failure caused by surface defects. The bubble-free and wrinkle-free surface makes the final product look neat and beautiful, improving the market competitiveness of the product. The adhesive layer 2 is precisely cut according to the B tooling to ensure that it fits perfectly with the plastic film 1 and the rubber layer 3, avoiding poor bonding or material waste due to size mismatch. The standardized cutting size simplifies the production process, reduces the time for manual adjustment, and improves the overall production efficiency. Rolling and storage can effectively protect the adhesive layer 2 and prevent it from being damaged or contaminated during storage and transportation. The rolled adhesive layer 2 is easy to manage and carry, saving storage space and improving logistics efficiency.

[0058] This setting ensures the uniformity and surface quality of the adhesive layer 2 through a precision calender and strict thickness control, enhances the bonding effect between the plastic film 1 and the rubber layer 3, and the standardized cutting size and winding storage simplify the production process and improve production efficiency and consistency of product quality.

[0059] Preferably, the preparation steps of the adhesive layer 2 are: ST1: The rubber type of the rubber layer 2 is chloroprene rubber, and the fillers used include carbon black, white carbon black, tackifier, accelerator CZ and sulfur. The ratio is 50-100 parts of chloroprene rubber, 20-60 parts of carbon black, 10-30 parts of white carbon black, 0-30 parts of tackifier, 0-5 parts of accelerator CZ and 0-5 parts of sulfur; ST2: Use internal mixer and open mixer for mixing and molding, the speed is 35 / min, the mixing temperature is 70℃, and the debinding temperature does not exceed 120℃; ST3: After refining and molding, the mixed rubber is sent to a four-roll calender for compression molding. The speed ratio of AB and BC rollers is controlled at 0.9, the speed ratio of CD roller is controlled at 1, the distance between AB rollers is controlled at 0.7mm, the distance between BC rollers is controlled at 0.55mm, and the distance between CD rollers is controlled at 0.8mm. The total thickness of the film is controlled between 0.58 and 0.64mm and rolled into shape; ST4: The film produced in step ST3 is cut into a set size using tooling B to obtain adhesive layer 2.

[0060] Through precise proportioning, the rubber layer 2 is ensured to have good mechanical properties, bonding effect and weather resistance, and the various components are fully mixed to form a uniform composite material. By adjusting the roller spacing and speed ratio, the total thickness of the film is ensured to be between 0.58mm and 0.64mm, providing stable mechanical properties, ensuring better bonding performance of the rubber layer 2, and improving the bonding force between the rubber layer 3 and the plastic film 1. At the same time, standardized dimensions and precise position laying ensure close fit between the layers.

[0061] The selection of different additives in this setting can adjust the performance of the adhesive layer 2 according to specific needs. By strictly controlling the mixing conditions, the finished products produced each time can be kept highly consistent, ensuring the stable quality of each batch of adhesive layer 2. Standardized dimensions simplify the production process, improve production efficiency and consistency of product quality, and precise cutting reduces the generation of excess materials and reduces costs.

[0062] Specifically, in step S2, the rubber layer 3 is a reinforcing material of the elastic support pad, and the rubber layer 3 is made by mixing, open refining, etc., natural rubber, styrene-butadiene rubber, EPDM rubber, nitrile rubber, etc.

[0063] By selecting appropriate rubber materials, the elastic support pad is provided with the necessary structural strength and elasticity, and the overall stability and durability are enhanced. The high elasticity and softness of the rubber material provide the product with good shock absorption and cushioning effects, improving the user experience. Different types of rubber materials can provide specific functions according to specific application requirements, such as weather resistance, chemical resistance, oil resistance, etc., extending the service life of the product.

[0064] This setting can optimize the production process while ensuring high product performance and meet the needs of different application scenarios by rationally selecting rubber materials and combining appropriate mixing or open mixing treatments.

[0065] Specifically, the rubber layer 3 is refined by an open mill, the thickness is controlled to be 3.8-4.2 mm, bubbles, wrinkles and other defects are not allowed on the surface, and the rubber layer 3 is cut into appropriate sizes by using a B tool.

[0066] Use a high-precision mixing mill to refine and control the thickness of the rubber layer 3, accurately adjust the roller spacing to ensure that the thickness of the rubber layer 3 is strictly controlled between 3.8mm and 4.2mm, maintain an appropriate roller temperature of usually 50℃ to 70℃ to ensure that the rubber material has good fluidity and uniformity, adjust the roller speed according to the material properties, and ensure that there are no bubbles, wrinkles or other defects on the surface of the rubber layer 3.

[0067] This arrangement ensures the uniformity and bonding effect of the rubber layer 3 through an open mill and strict thickness and surface quality control. The standardized cutting size simplifies the production process and improves production efficiency and consistency of product quality.

[0068] Specifically, in step S2, the length and width dimensions of tooling A are 300 mm×200 mm, and the length and width dimensions of tooling B are 290 mm×190 mm.

[0069] The length and width of tool B are 10mm smaller than those of tool A. Tool A is used to cut plastic film 1, and tool B is used to cut rubber layer 3 and adhesive layer 2. Ensure that rubber layer 3 and adhesive layer 2 are slightly smaller than plastic film 1 so that an appropriate edge distance of 5mm can be left during assembly to prevent edge overflow from affecting the appearance and avoid poor bonding or material waste due to size mismatch.

[0070] The setting of tooling of different sizes ensures the precise fit between the layers of materials, avoiding poor bonding or material waste caused by size mismatch. The appropriate small size difference ensures that there is enough space between the layers for bonding, and the edges are neat and beautiful. The standardized size simplifies the production process, reduces the time of manual adjustment, and improves the overall production efficiency.

[0071] Specifically, in step S3, the distance between the rubber layer 3 and the adhesive layer 2 and the four ends of the plastic film 1 is 5 mm.

[0072] The 5mm edge distance can effectively prevent the adhesive layer 2 from overflowing to the edge of the plastic film 1 during the pressing process, keeping the product appearance neat. Even if there is a small amount of overflow, the 5mm reserved space makes subsequent cleaning easier and reduces the time and difficulty of trimming. The appropriate edge distance ensures a close fit between the layers of material, avoiding poor bonding or bubble formation caused by tight edges. Sufficient edge space helps to enhance the quality of the bonding interface and provide a stronger bond. The 5mm edge distance provides operators with a clear reference line for accurate laying of the rubber layer 3 and the adhesive layer 2, reduces the possibility of human error, simplifies the production process, improves production efficiency and consistency of product quality, enhances the overall appearance quality of the product, and increases market competitiveness.

[0073] Specifically, in step S5, the press is a flat-plate vulcanizing press, and the specifications and models may be 200t, 300t and 400t.

[0074] The flat vulcanizer can provide uniform pressure distribution throughout the pressing process, ensuring close fit and strong bonding between the layers of material. By applying appropriate pressing force, the air between the layers can be effectively removed, reducing the formation of bubbles and wrinkles and improving the surface quality.

[0075] Flat plate vulcanizers are usually equipped with advanced temperature control systems that can maintain a stable temperature during the curing process to ensure full vulcanization of rubber and other materials. Precise time control makes the curing process more controllable and ensures consistent curing effects for each batch of products. Modern flat plate vulcanizers mostly use automated control systems to reduce manual intervention and improve production efficiency.

[0076] This setting can optimize the production process while ensuring product high performance and meet the needs of different application scenarios by reasonably selecting and using 200t, 300t or 400t flat vulcanizers.

[0077] Specifically, in step S6, the distance between the plastic film 1 and the four ends of the mold cavity is required to be 2-4 mm.

[0078] The edge distance of 2-4mm can effectively prevent the plastic film 1 from exceeding the range of the mold cavity during the pressing process, avoid overflow, and keep the product appearance neat. The appropriate edge distance ensures the close fit between the plastic film 1 and the mold cavity, avoids poor bonding or bubble formation caused by tight edges, helps to enhance the quality of the bonding interface, and provides a stronger bonding force.

[0079] Specifically, in step S7, after preheating for 2-3 minutes, the mold is closed and the pressure is maintained. During this period, the mold is observed to see if there is any abnormality. Then, the equipment curing temperature is adjusted to 150° C. and the curing pressure is adjusted to 40 minutes.

[0080] 2-3 minutes of preheating ensures uniform temperature rise of the mold and the material, reduces stress and thermal shock caused by temperature difference, and improves the bonding effect. Mold closing and pressure holding ensures the close fit of each layer of material, monitors the mold status in real time, promptly detects and handles abnormal situations, and ensures production safety and quality. The curing temperature of 150°C ensures full vulcanization or cross-linking of the material, and does not cause material degradation due to excessive temperature, providing efficient curing effect. The 40-minute curing time ensures uniform heating of the entire product, enhances the mechanical properties and durability of the product, and reduces the possibility of rework.

[0081] Specifically, in step S7, the oven is 2.3 m high and 1.5 m wide, and the oven temperature ranges from 0 to 200°C.

[0082] The larger size can accommodate larger or more complex shaped products, suitable for batch production and large product processing, and the large enough space is convenient for operators to enter and exit and place molds, which improves the convenience and safety of operation. The temperature range from room temperature to 200℃ can meet the needs of different materials and processes, and is suitable for a variety of curing and heat treatment processes. The oven is usually equipped with an advanced temperature control system, which can achieve precise control over the entire temperature range to ensure the consistency of each batch of products. Example 1

[0083] Preparation of plastic film 1: Cut the plastic film 1 into the same size as tooling A and place it at the lower end of the mold. The plastic film 1 is 1200 mm wide and has 3 mm wide grooves at both ends to ensure that the plastic film 1 does not slip during laying.

[0084] Preparation of the adhesive layer 2: The adhesive layer 2 is mixed and formed according to the ratio of 100 parts of chloroprene rubber, 30 parts of carbon black, 15 parts of white carbon black, 5 parts of tackifier, 1.5 parts of accelerator CZ and 1 part of sulfur, and a precision calender is used to control the thickness between 0.58mm-0.64mm, and it is pressed into a roll, cut into the same size using B tooling, and laid flat in the middle of the plastic film 1.

[0085] Preparation of rubber layer 3. The rubber type can be natural rubber or nitrile rubber. Fillers are added and mixed through internal mixing and open mixing. The thickness is controlled between 3.8mm-4.2mm. It is cut into the same size using B tooling and laid on top of rubber layer 2. It is required that rubber layer 2 and rubber layer 3 completely overlap.

[0086] Pre-pressing and molding: after laying the rubber layer 3, place it in a 200t press, set the temperature at 23±5℃, close the mold and pre-press for 20 minutes.

[0087] Curing and bonding: After pre-pressing for 20 minutes, heat up and cure. The required curing temperature is 150°C, the curing time is 40 minutes, and the curing pressure is 12MPa. Example 2

[0088] Preparation of plastic film 1: Cut the plastic film 1 into the same size as tooling A and place it at the lower end of the mold. The plastic film 1 is 1200 mm wide and has 3 mm wide grooves at both ends to ensure that the plastic film 1 does not slip during laying.

[0089] Preparation of adhesive layer 2: Adhesive layer 2 is mixed and formed according to the ratio of 100 parts of chloroprene rubber, 30 parts of carbon black, 15 parts of white carbon black, 10 parts of tackifier, 1.5 parts of accelerator CZ and 1 part of sulfur, and a precision calender is used to control the thickness between 0.58mm-0.64mm, and it is pressed into a roll, cut into the same size using B tooling, and laid flat in the middle of plastic film 1.

[0090] The rubber layer 3 is prepared by an open mill, and the thickness is controlled to be 3.8-4.2mm. No bubbles, wrinkles or other defects are allowed on the surface. The rubber is cut into the same size by using the B tooling and laid on the rubber layer 2. The rubber can be natural rubber or nitrile rubber. The filler is added and mixed by mixing and forming by the method of internal mixing and open mixing. The thickness is controlled to be between 3.8mm and 4.2mm. The rubber is cut into the same size by using the B tooling and laid on the rubber layer 2. The rubber layer 2 and the rubber layer 3 are required to overlap completely.

[0091] Pre-pressing and molding: after laying the rubber layer 3, place it in a 200t press, set the temperature at 23±5℃, close the mold and pre-press for 20 minutes.

[0092] Curing and bonding: After pre-pressing for 20 minutes, heat up and cure. The required curing temperature is 150°C, the curing time is 40 minutes, and the curing pressure is 12MPa. Example 3

[0093] Preparation of plastic film 1: Cut the plastic film 1 into the same size as tooling A and place it at the lower end of the mold. The plastic film 1 is 1200 mm wide and has 3 mm wide grooves at both ends to ensure that the plastic film 1 does not slip during laying.

[0094] Preparation of the adhesive layer 2: The adhesive layer 2 is mixed and formed according to the ratio of 100 parts of chloroprene rubber, 30 parts of carbon black, 15 parts of white carbon black, 15 parts of tackifier, 1.5 parts of accelerator CZ and 1 part of sulfur, and a precision calender is used to control the thickness between 0.58mm-0.64mm, and it is pressed into a roll, cut into the same size using B tooling, and laid flat in the middle of the plastic film 1.

[0095] The rubber layer 3 is prepared by an open mill, and the thickness is controlled to be 3.8-4.2mm. No bubbles, wrinkles or other defects are allowed on the surface. It is cut into the same size by using the B tooling and laid on the rubber layer 2. The rubber type can be natural rubber or nitrile rubber. The filler is added and mixed by the method of internal mixing and open mixing. The thickness of the rubber layer 3 is controlled between 3.8mm-4.2mm, and it is cut into the same size by using the B tooling and laid on the rubber layer 2. It is required that the rubber layer 2 and the rubber layer 3 are completely overlapped.

[0096] Pre-pressing and molding: after laying the rubber layer 3, place it in a 200t press, set the temperature at 23±5℃, close the mold and pre-press for 20 minutes.

[0097] Curing and bonding: After pre-pressing for 20 minutes, heat up and cure. The required curing temperature is 150°C, the curing time is 40 minutes, and the curing pressure is 12MPa.

[0098] Comparative Example 1 Mould cleaning: Use a mould cleaning agent to clean the mould. After cleaning the mould surface, apply a release agent to the mould surface with a clean gauze.

[0099] Preparation of plastic film 1: cut the plastic film 1 into appropriate size according to tooling A, cut the rubber layer 3 into appropriate size using tooling B, use a 1.5-inch brush, dip a small amount of detergent, clean the surface of the sodium naphthalene layer of the plastic film 1, ensure that there are no other impurities on the surface of the plastic film 1, let it stand for 5 minutes, set aside, use a 1.5-inch brush, dip a small amount of Chemlock, brush on one side of the sodium naphthalene treatment layer of the plastic film 1, ensure that the adhesive is evenly applied, and no missing is allowed.

[0100] The rubber layer 3 is prepared by using an open mill, and the thickness is controlled to be 3.8-4.2mm. No bubbles, wrinkles or other defects are allowed on the surface. The rubber layer 3 is cut into the same size using the B tooling and laid on the rubber layer 2. The rubber type of the rubber layer 3 can be natural rubber or nitrile rubber. The rubber layer 3 is mixed and formed by adding fillers through internal mixing and open mixing. The thickness is controlled between 3.8mm-4.2mm, and the rubber layer 2 is cut into the same size using the B tooling and laid on the rubber layer 2. The rubber layer 2 and the rubber layer 3 are required to overlap completely.

[0101] Pre-pressing and molding: after laying the rubber layer 3, place it in a 200t press, set the temperature at 23±5℃, close the mold and pre-press for 20 minutes.

[0102] Curing and bonding: After pre-pressing for 20 minutes, heat up and cure. The required curing temperature is 150°C, the curing time is 40 minutes, and the curing pressure is 12MPa.

[0103] Comparative Example 2 Mould cleaning: Use a mould cleaning agent to clean the mould. After cleaning the mould surface, apply a release agent to the mould surface with a clean gauze.

[0104] Preparation of plastic film 1: cut the plastic film 1 into appropriate size according to tooling A, cut the rubber layer 3 into appropriate size using tooling B, use a 1.5-inch brush, dip a small amount of detergent, clean the surface of the sodium naphthalene layer of the plastic film 1, ensure that there are no other impurities on the surface of the plastic film 1, let it stand for 5 minutes, set aside, use a 1.5-inch brush, dip a small amount of roller glue, and brush one side of the sodium naphthalene treatment layer of the plastic film 1 to ensure that the adhesive is evenly applied, and no missing parts are allowed.

[0105] The rubber layer 3 is prepared by using an open mill, and the thickness is controlled to be 3.8-4.2mm. No bubbles, wrinkles or other defects are allowed on the surface. The rubber layer 3 is cut into the same size using the B tooling and laid on the rubber layer 2. The rubber type of the rubber layer 3 can be natural rubber or nitrile rubber. The rubber layer 3 is mixed and formed by adding fillers through internal mixing and open mixing. The thickness is controlled between 3.8mm-4.2mm, and the rubber layer 2 is cut into the same size using the B tooling and laid on the rubber layer 2. The rubber layer 2 and the rubber layer 3 are required to overlap completely.

[0106] Pre-pressing and molding: after laying the rubber layer 3, place it in a 200t press, set the temperature at 23±5℃, close the mold and pre-press for 20 minutes.

[0107] Curing and bonding: After pre-pressing for 20 minutes, heat up and cure. The required curing temperature is 150°C, the curing time is 40 minutes, and the curing pressure is 12MPa.

[0108] Comparative Example 3 Mould cleaning: Use a mould cleaning agent to clean the mould. After cleaning the mould surface, apply a release agent to the mould surface with a clean gauze.

[0109] Preparation of plastic film 1: Cut the plastic film 1 into appropriate size according to tooling A. Use a 1.5-inch brush with a small amount of detergent to clean the surface of the sodium naphthalene layer of the plastic film 1. Ensure that there are no other impurities on the surface of the plastic film 1. Let it stand for 5 minutes and then set aside.

[0110] The rubber layer 3 is prepared by an open mill, and the thickness is controlled to be 3.8-4.2mm. No bubbles, wrinkles or other defects are allowed on the surface. The rubber is cut into the same size by using the B tooling and laid on the rubber layer 2. The rubber type of the rubber layer 3 can be natural rubber or nitrile rubber. The filler is added and mixed by the method of internal mixing and open mixing. The thickness is controlled between 3.8mm-4.2mm, and the rubber is cut into the same size by using the B tooling and laid on the rubber layer 2. The rubber layer 2 and the rubber layer 3 are required to overlap completely.

[0111] Pre-pressing and molding: after laying the rubber layer 3, place it in a 200t press, set the temperature at 23±5℃, close the mold and pre-press for 20 minutes.

[0112] Curing and bonding: After pre-pressing for 20 minutes, heat up and cure. The required curing temperature is 150°C, the curing time is 40 minutes, and the curing pressure is 12MPa.

[0113] In step S8, the bonding strength between the plastic film 1 and the rubber in the elastomeric support pad material is compared with the bonding strength between the plastic film 1 and the rubber using the traditional adhesive. The obtained samples are cut into three samples of 200 mm in length, 25 mm in width and 5 mm in thickness using a utility knife, and the samples are placed in a universal tensile testing machine to test the 180° peel strength. The performance is shown in the following table.

[0114] Table 1. Performance comparison between examples and comparative examples

[0115] As can be seen from Table 1, in Comparative Examples 1-2, the conventional adhesive was used to bond the rubber layer 3 and the plastic film 1, and the bonding strengths after molding were 0.9 MPa and 2.5 MPa, respectively. In Examples 1-3, the bonding strengths of the rubber layer 3 and the plastic film 1 without the conventional adhesive in the technical solution of the present invention were significantly higher than those of the conventional processing solution, and the bonding strengths reached 4.5 MPa, 5.3 MPa and 6.4 MPa, respectively.

[0116] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An adhesive-free compounding molding method, characterized in that: The specific steps include: S1: Mould cleaning; S2: cutting, cutting the plastic film (1) to a set size using tool A, and cutting the rubber layer (3) and the adhesive layer (2) to a set size using tool B, wherein the thickness of the adhesive layer (2) is in the range of 0.58 to 0.64 mm; S3: Laying the rubber layer (3) and the adhesive layer (2), the adhesive layer (2) and the rubber layer (3) are laid in sequence on the surface of the plastic film (1), and the distance between the rubber layer (3) and the adhesive layer (2) and the edge of the plastic film (1) is 2-8 mm; S4: inspecting the rubber layer (3) and the adhesive layer (2), and cutting open any bulges or bubbles on the surface of the rubber layer (3) and the adhesive layer (2), and removing any impurities; S5: Pre-forming in a press, after the adhesive layer (2) is laid, it is placed in a press and pressed for more than 20 minutes before being taken out; S6: before curing begins, the plastic film (1) attached to the rubber layer (3) and the adhesive layer (2) is placed in the middle of the mold, with the plastic film (1) being 2-6 mm away from the edge of the mold cavity; S7: After the mold is installed, slowly close the mold, preheat for 1-6 minutes, close the mold and maintain pressure. During this period, observe whether the mold is abnormal, and then adjust the oven curing temperature to 100-200℃ and the curing time to 30-50 minutes; S8: Demolding. After curing is completed, the product is completely removed from the mold to obtain a high-quality elastomer support pad material.

2. The adhesive-free compounding molding method according to claim 1, characterized in that: In step S2, the plastic film (1) is one of a polyester film, a polyethylene film, a polypropylene film and a polytetrafluoroethylene film, and the plastic film (1) is drawn by pultrusion or curling.

3. The adhesive-free compounding molding method according to claim 1, characterized in that: The plastic film (1) is cut to a set size using tooling A, the surface of the plastic film (1) needs to be treated with sodium naphthalene, and the thickness is between 0.4 mm and 0.6 mm.

4. The adhesive-free compounding molding method according to claim 1, characterized in that: In step S2, the adhesive layer (2) is a kind of chloroprene rubber or brominated butyl rubber. The adhesive layer (2) is processed by a precision calender, and bubbles, wrinkles and other defects are not allowed on the surface. After being produced, it is cut to a set size by using a B tooling, and rolled up for storage.

5. The adhesive-free compounding molding method according to claim 4, characterized in that: The steps for preparing the adhesive layer (2) are as follows: ST1: The rubber type of the rubber layer (2) is chloroprene rubber, and the fillers used include carbon black, white carbon black, tackifier, accelerator CZ and sulfur, with a ratio of 50-100 parts of chloroprene rubber, 20-60 parts of carbon black, 10-30 parts of white carbon black, 0-30 parts of tackifier, 0-5 parts of accelerator CZ and 0-5 parts of sulfur; ST2: Use internal mixer and open mixer for mixing and molding, the speed is 35 / min, the mixing temperature is 70℃, and the debinding temperature does not exceed 120℃; ST3: After refining and molding, the mixed rubber is sent to a four-roll calender for compression molding. The speed ratio of AB and BC rollers is controlled at 0.9, the speed ratio of CD roller is controlled at 1, the distance between AB rollers is controlled at 0.7mm, the distance between BC rollers is controlled at 0.55mm, and the distance between CD rollers is controlled at 0.8mm. The total thickness of the film is controlled between 0.58 and 0.64mm and rolled into shape; ST4: The film produced in step ST3 is cut into a set size using tool B to obtain the adhesive layer (2).

6. The adhesive-free compounding molding method according to claim 1, characterized in that: In step S2, the rubber layer (3) is one or more of natural rubber, styrene-butadiene rubber, EPDM rubber, and nitrile rubber, and is refined using an open mill, with a thickness controlled at 3.8 to 4.2 mm. No bubbles, wrinkles, or other defects are allowed on the surface, and the rubber layer (3) is cut to a set size using a B tool.

7. The adhesive-free compounding molding method according to claim 1, characterized in that: In step S2, the length and width dimensions of tool A are 300 mm×200 mm, and the length and width dimensions of tool B are 290 mm×190 mm.

8. The adhesive-free compounding molding method according to claim 1, characterized in that: In step S5, the press is a flat vulcanizing press with a specification of 200t, 300t or 400t.

9. The adhesive-free compounding molding method according to claim 1, characterized in that: In step S7, the oven is 2.3 m high and 1.5 m wide, and the oven temperature ranges from 0 to 200°C.

10. The adhesive-free compounding molding method according to claim 1, characterized in that: The step also includes step S9, cutting the elastomeric support pad material in S8 into three samples each with a length of 200 mm, a width of 25 mm, and a thickness of 5 mm, placing the samples in a universal tensile testing machine, and testing the 180° peel strength of the samples.

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