Laminating composite equipment and cross composite film production process

Abstract

The invention relates to the field of building films, and discloses film spraying composite equipment and a crossed composite film production process, and the film spraying composite equipment comprises the following steps: S1, carrying out surface pretreatment on a main film base material; s2, preparing a dynamic reaction adhesion promoting layer coating solution; s3, the surface of the main film base material is coated with the dynamic reaction adhesion promoting layer; s4, performing multi-layer compounding on the main film base material, the dynamic reaction adhesion promoting layer and the secondary film base material through extrusion co-extrusion equipment; s5, carrying out hot-pressing curing treatment on the compounded film; and S6, rolling to obtain a finished product. The technical scheme that the primary film substrate and the secondary film substrate are both subjected to corona treatment is adopted, polar groups such as carboxyl and hydroxyl are introduced to the surfaces of the substrates, the interface adhesion performance is remarkably improved, the effect of high peel strength of the multi-layer composite film is achieved, and the problems that the interface bonding strength is insufficient and the multi-layer film is prone to layering in the high-humidity and high-temperature environment are solved.

Description

Technical Field

[0001] The invention relates to the technical field of building membranes, in particular to a laminating composite device and a cross composite membrane production process. Background Art

[0002] As a new functional film material widely used in packaging, construction and industrial fields, cross-laminated film has certain mechanical strength, adhesion performance and environmental adaptability due to its multi-layer composite structure. This film is usually made of substrates with different physical or chemical properties through a composite process. The typical production process includes substrate treatment, adhesive layer preparation and coating, extrusion composite and winding process. In order to meet the actual application needs, the production process of cross-laminated film needs to take into account the interface bonding force between different substrates, the thickness uniformity of the multi-layer film and the consistency of surface properties.

[0003] Although the production technology of cross-composite membranes has been developed, the existing technology still has obvious deficiencies in improving the interfacial bonding strength of multilayer membranes and controlling the uniformity of membrane structure. The surface pretreatment of the substrate is often disconnected from the composite process, resulting in unstable surface polarity enhancement effect and failure to form efficient interfacial chemical bonding. Secondly, the membrane is easily affected by tension fluctuations during high-speed production, resulting in reduced interfacial bonding strength and the appearance of surface defects. Especially when used in hot and humid or high-stress environments, these membranes are more likely to delaminate, warp or break, thus affecting their long-term performance. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a laminating composite equipment and a cross-composite film production process, which solve the problems in the prior art of insufficient interface bonding of multi-layer films, disconnection between substrate surface pretreatment and composite process, unstable performance caused by uneven distribution of adhesion layer, and surface defects and stratification of film materials caused by tension fluctuations in high-speed production.

[0005] To achieve the above objectives, the present invention is implemented by the following technical scheme: A cross composite membrane production process comprises the following steps: S1. Surface pretreatment of the main film substrate; the main film substrate is the base layer of the entire cross-composite film structure, and its main component is polyethylene (PE) or polypropylene (PP). Since PE and PP are non-polar materials, their surface energy is low and their adhesion performance is poor when directly composited. Therefore, surface pretreatment is required to increase the surface polarity and interfacial energy to enhance its bonding with the dynamic reaction adhesion promoting layer.

[0006] S2, preparing a dynamic reaction adhesion promoting layer coating liquid; the coating liquid comprises the following components: Polyurethane (PU) or polyvinyl alcohol (PVA): As the matrix material, it provides good adhesion and dynamic cross-linking ability.

[0007] γ-Aminopropyltriethoxysilane: As a self-assembling molecule, it forms silicon-oxygen bonds at the interface to enhance adhesion strength.

[0008] Dihydroxybenzene: As a dynamic cross-linker, it improves the interface strength through dynamic chemical bonds (hydrogen bonds and π-π interactions).

[0009] Nano-graphene oxide (fGO) and functionalized silica (fSiO2): Improve the mechanical strength and interfacial bonding of the coating through nano-enhancement.

[0010] Ethanol / water mixed solvent: ensures uniformity and dispersion of the coating liquid.

[0011] Dynamic cross-linking: Dihydroxybenzene and polyurethane matrix form chemical bonds at the composite interface through a reversible dynamic cross-linking reaction. This dynamic cross-linking can adapt to the heat pressure and mechanical stress during the composite process, thereby improving the adhesion performance.

[0012] Interface self-assembly: γ-Aminopropyltriethoxysilane reacts with the substrate surface through its triethoxy group to form a stable silicon-oxygen bond (Si-O-Si), while its amino part combines with the polar groups in the dynamic reactive adhesion promoting layer to form a cross-linked network.

[0013] S3, coating the dynamic reaction adhesion promoting layer on the surface of the main film substrate; the dynamic reaction adhesion promoting layer is evenly coated on the surface of the main film substrate that has been surface pretreated by scraping or casting process. The coating thickness is controlled at 0.5-1.5 μm to ensure that the substrate surface can be covered without increasing the thickness of the composite film.

[0014] The applied dynamic reaction layer forms a strong interfacial chemical bond (silicon-oxygen bond) between the self-assembled molecules (γ-aminopropyltriethoxysilane) and the substrate surface, further enhancing the adhesion. In addition, the uniform distribution of nanoparticles can fill the microporous structure on the substrate surface, thereby improving the coverage of the coating and enhancing the overall adhesion performance.

[0015] S4. The main film substrate, the dynamic reaction adhesion promoting layer and the secondary film substrate are multi-layered by extrusion co-extrusion equipment; the main film substrate, the dynamic reaction adhesion promoting layer and the secondary film substrate are synchronously compounded in the co-extrusion equipment. The co-extrusion equipment adopts a multi-layer co-extrusion die head to achieve fusion of the three layers of materials at the interface under high temperature and high pressure.

[0016] Interfacial chemical reaction: Under the high temperature conditions of extrusion co-extrusion (main substrate 190-250℃, secondary substrate 190-250℃, interlayer 150-200℃), the γ-aminopropyltriethoxysilane in the dynamic reaction adhesion promotion layer forms a chemical bond with the surface of the secondary membrane substrate, and at the same time, dihydroxybenzene undergoes a dynamic cross-linking reaction with the polyurethane matrix to generate a cross-linked network structure, ensuring that the composite membrane interface has high-strength bonding.

[0017] S5, subjecting the composite film to a hot press curing treatment; the composite film is cured by a hot press curing device, the hot press temperature is 120-150°C, the pressure is 10-20MPa, and the time is 5-10 minutes. Hot press curing further completes the cross-linking reaction of the dynamic reaction adhesion promoting layer and enhances the overall strength of the film.

[0018] Under hot pressing conditions, the dynamic cross-linking reaction between dihydroxybenzene in the dynamic reaction adhesion promoting layer and the polyurethane matrix is ​​fully carried out to form a stable three-dimensional cross-linked network structure.

[0019] γ-Aminopropyltriethoxysilane further reacts with the substrate surface to form more silicon-oxygen bonds, thereby increasing the interfacial adhesion strength.

[0020] Nanomaterials can be more evenly distributed in the coating under hot pressing conditions, optimizing the mechanical anchoring effect.

[0021] S6, winding to obtain the finished product; during the winding process, tension control ensures the flatness and thickness uniformity of the film, while avoiding interface separation or performance degradation caused by excessive stretching.

[0022] The main film substrate includes 80-95% by weight of polyethylene or polypropylene, 3-10% by weight of maleic anhydride grafted polymer, and 0.5-2% by weight of processing aid; The dynamic reaction adhesion promoting layer comprises 60-80 mass parts of polyurethane or polyvinyl alcohol, 3-8 mass parts of γ-aminopropyltriethoxysilane, 2-5 mass parts of dihydroxybenzene, 3-6 mass parts of nanographene oxide, 4-8 mass parts of functionalized silicon dioxide and 10-20 mass parts of ethanol / water mixed solvent; The secondary film substrate comprises 80-95 weight percent of polyethylene or polypropylene, 3-10 weight percent of maleic anhydride grafted polymer, and 0.5-2 weight percent of processing aid.

[0023] Surface energy enhancement and interface polarization (S1): Corona treatment enhances the surface polarity of the substrate, providing a chemical bonding basis for the subsequent adhesion-promoting layer.

[0024] Synergistic effect of dynamic cross-linking and self-assembly (S2-S3): The dynamic reaction layer forms a dual chemical and physical bond at the interface, which improves the adhesion strength and interface stability.

[0025] Nano-enhancement and mechanical anchoring effect (S4): Nanomaterials provide microscopic embedding and reinforcement in the interface layer, further improving the mechanical properties of the film.

[0026] Full reactivity of hot press curing (S5): Under hot press curing conditions, chemical crosslinking and molecular diffusion are fully carried out, ensuring that the performance of the composite film is optimal.

[0027] Preferably, the method for surface pretreatment of the main film substrate in S1 includes low-temperature plasma treatment, and the treatment parameters are power 40-80W, treatment time 30-90 seconds, distance from electrode 5-10mm, and gas flow rate 20-50sccm.

[0028] Mechanism of surface polarity enhancement: The discharge phenomenon generated by the low-temperature plasma through the high-voltage electric field triggers physical and chemical changes on the surface of the main film substrate, including molecular chain breakage and free radical generation. These free radicals react with oxygen in the air or oxygen environment to generate polar groups such as hydroxyl (-OH) and carboxyl (-COOH). The introduction of these polar groups enables the non-polar PE or PP surface to have a stronger chemical and physical bond with the subsequent dynamic reaction adhesion promotion layer.

[0029] Surface roughening mechanism: Microscopic etching during corona discharge forms fine concave and convex structures on the substrate surface. This surface roughening not only increases the contact area between the coating and the substrate, but also further enhances the adhesion through the physical anchoring effect.

[0030] Preferably, the method for preparing the dynamic reaction adhesion promoting layer coating liquid in S2 comprises the following steps: Dissolving polyurethane or polyvinyl alcohol in an ethanol / water mixed solvent; Use a 1:1 mixture of ethanol and water to ensure that the solvent can fully dissolve the polyurethane or polyvinyl alcohol.

[0031] Polyurethane is a polymer material with extremely high adhesion, while polyvinyl alcohol is known for its excellent polarity and chemical compatibility. Both can be used as the base material of the dynamic reaction coating layer to provide a basis for interfacial adhesion.

[0032] Solubility mechanism: The mixed solvent of ethanol and water can dissolve both the non-polar part (polyether segment) and the polar part (amino group, hydroxyl group) of polyurethane, ensuring that the polyurethane can be completely dissolved and form a uniform solution. The strong polar group (hydroxyl group) of polyvinyl alcohol has good compatibility with water, making it dissolve quickly.

[0033] Contribution of matrix properties: Polyurethane provides high elasticity and dynamic cross-linking ability in the coating layer, while the strong polarity and water solubility of polyvinyl alcohol can enhance the surface adhesion performance of the coating layer.

[0034] adding γ-aminopropyltriethoxysilane, dihydroxybenzene, nanographene oxide and functionalized silica in sequence; γ-Aminopropyltriethoxysilane (3-8 parts by mass) is first added to the solution as a self-assembling molecule. Its triethoxy part is hydrolyzed to form a silanol group, which further forms a silicon-oxygen bond (Si-O-Si) with the polyurethane or polyvinyl alcohol and the surface of the substrate.

[0035] Subsequently, dihydroxybenzene (2 to 5 parts by weight) is added as a dynamic crosslinking agent, the hydroxyl groups of which can undergo a dynamic chemical reaction with the carbonyl groups in the polyurethane molecules to form a reversible crosslinking network.

[0036] The third step is to add nano graphene oxide (3 to 6 parts by mass), which has hydroxyl and carboxyl groups on its surface, and is physically or chemically bonded to the coating layer substrate, while enhancing adhesion properties through high specific surface area.

[0037] Finally, functionalized silica (4 to 8 parts by mass) is added. The surface of the silica modified by the silane coupling agent has polar groups (hydroxyl, amine), which can form chemical bonds with the coating layer matrix, fill interface defects, and provide mechanical reinforcement effects.

[0038] Self-assembly mechanism of γ-aminopropyltriethoxysilane: triethoxysilane is hydrolyzed in the solution to generate silanol groups, which combine with the hydroxyl groups on the surface of the substrate through condensation reaction to form a stable silicon-oxygen bond (Si-O-Si) to achieve chemical bonding. At the same time, its amino part can hydrogen bond with the polymer chain of the dynamic reaction layer to improve the interface bonding force.

[0039] Preferably, the method of coating the dynamic reaction adhesion promoting layer in S3 is a scraping or casting process, and the coating amount is 0.1 to 0.5 g / m 2 The coating thickness is 0.5-1.5 μm, the initial drying temperature is 70-100°C, and the drying time is 3-5 minutes.

[0040] Coating method: scraping or casting process; Scraping process: Scraping is a simple and efficient coating method that uses a scraper to precisely control the coating on the substrate surface. It is suitable for fine coating layer thickness control and is widely used in large-scale production. By adjusting the gap height of the scraper and the pressure applied, the coating liquid can be evenly distributed on the substrate surface.

[0041] Casting process: Cast coating is a process of evenly spreading the coating liquid on the surface of the substrate and achieving thin layer coating by precise control of the coating device. It is suitable for processes that require high coating uniformity.

[0042] Preliminary drying process: temperature 70-100°C, time 3-5 minutes; the coated substrate is dried at a preliminary drying temperature of 70-100°C for 3-5 minutes; this process is intended to remove the solvent (ethanol and water) in the coating liquid, while allowing the components in the adhesion promoting layer (dihydroxybenzene, γ-aminopropyltriethoxysilane) to complete partial chemical reactions.

[0043] Solvent evaporation mechanism: The mixed solvent of ethanol and water in the coating liquid evaporates rapidly at 70-100°C, leaving the solid components (polyurethane, nano-graphene oxide, etc.) evenly deposited on the surface of the substrate to form a preliminary cured adhesion layer.

[0044] Chemical pre-reaction mechanism: During the drying process, the γ-aminopropyltriethoxysilane in the coating layer is hydrolyzed to generate silanol (Si-OH) and further reacts with the substrate surface or polyurethane / polyvinyl alcohol matrix to generate silicon oxygen bonds (Si-O-Si). At the same time, the hydroxyl groups of dihydroxybenzene also form preliminary hydrogen bonds or dynamic chemical bonds with the polar groups in the coating matrix, thereby enhancing the adhesion performance of the coating layer.

[0045] Preferably, the parameters of the extrusion co-extrusion process in S4 are: the extrusion temperature of the main substrate layer is 190-250°C, the extrusion temperature of the interlayer is 150-200°C, the extrusion temperature of the secondary substrate layer is 190-250°C, the extrusion speed is 100-150m / min, and the pressure is 20-50MPa.

[0046] Temperature control: main substrate layer 190~250℃, interlayer 150~200℃, secondary substrate layer 190~250℃; In the extrusion co-extrusion process, the temperature setting of each layer of material is the core parameter, and the temperature range needs to be precisely adjusted according to the melting characteristics of different materials: Main substrate layer (PE or PP): The temperature range of 190-250°C can ensure that it is in a molten flow state, thereby achieving effective bonding with the adhesive layer during the extrusion process.

[0047] Dynamic reaction adhesion promoting interlayer: The temperature of 150-200℃ can not only maintain the fluidity of the coating layer and promote the interface reaction, but also avoid decomposition caused by excessively high temperature.

[0048] Secondary base material layer (PE or PP): The temperature range is consistent with the primary base material layer to ensure the final overall melt compounding effect.

[0049] Dynamic reaction and chemical bonding mechanism: The dynamic crosslinker (dihydroxybenzene) in the adhesion promotion layer reacts chemically with the substrate surface or adjacent substrates at a temperature of 150-200°C to form a dynamic crosslinking network. In addition, the silanol groups of γ-aminopropyltriethoxysilane react with the hydroxyl groups on the substrate surface or the groups of the dynamic reaction adhesion promotion layer to form silicon oxygen bonds (Si-O-Si), further enhancing the chemical bonding force.

[0050] Thermal diffusion mechanism: Under high temperature conditions, thermal diffusion occurs between interface molecules, increasing the interpenetration and intercalation of molecular chains, further improving the interface adhesion strength.

[0051] Extrusion speed: 100-150 m / min; The extrusion speed determines the synchronous fluidity and composite efficiency of the multi-layer materials during the co-extrusion process. The preferred range of 100-150 m / min can not only meet the efficiency requirements of industrial production, but also ensure that each layer of material has enough bonding time at the interface.

[0052] Extrusion pressure: 20~50MP; Extrusion pressure is a key parameter to ensure that the multi-layer materials are tightly combined in the die. Too low pressure will lead to insufficient bonding between materials and increased interface defects, while too high pressure will lead to insufficient material fluidity and delamination. The preferred range of 20-50MPa can ensure that each layer of material is evenly stressed in the die and achieve efficient bonding.

[0053] Compounding process in multi-layer co-extrusion die: The multi-layer co-extrusion die is the core device of this process. Its design enables the main substrate layer, dynamic reaction adhesion promotion layer and secondary substrate layer to complete synchronous flow and compounding in the die. By optimizing the flow channel design of the die, the flow rate of each layer of material in the die is consistent to avoid uneven flow distribution.

[0054] Mechanism of interface distribution uniformity: The design of the die flow channel ensures that each layer of material has the same flow rate and thickness distribution at the die outlet, thereby avoiding thickness differences or stratification at the interface caused by uneven flow.

[0055] Layered composite mechanism: The adhesion promoting layer forms a continuous intermediate layer at the interface through synchronous melt flow with the primary substrate and the secondary substrate in the die head, thereby enhancing the adhesion strength of the overall composite film.

[0056] Preferably, the parameters of the hot pressing curing in S5 are a hot pressing temperature of 120 to 150° C., a pressure of 10 to 20 MPa, and a time of 5 to 10 minutes.

[0057] Hot pressing temperature: 120~150℃ The setting of hot pressing temperature must meet the following requirements: Ensure that the chemical reaction (dynamic cross-linking reaction, silicon-oxygen bond formation) in the dynamic reaction adhesion promoting layer is fully completed within the optimal temperature range; At the same time, avoid high temperatures that may cause thermal decomposition of the substrate or degradation of the coating performance.

[0058] Dynamic cross-linking reaction mechanism: At a hot pressing temperature of 120-150°C, the cross-linking agent (dihydroxybenzene) in the dynamic reaction adhesion promotion layer undergoes a reversible cross-linking reaction with the carbonyl or hydroxyl groups in the polyurethane or polyvinyl alcohol matrix. This dynamic cross-linking can form a three-dimensional cross-linked network structure at the interface, greatly improving the adhesion strength and interface stability.

[0059] Mechanism of silicon-oxygen bond formation: Under hot-pressing temperature, the unreacted silanol groups (Si-OH) of γ-aminopropyltriethoxysilane in the coating liquid undergo further condensation reaction to form more silicon-oxygen bonds (Si-O-Si) with the substrate surface or dynamic reaction layer, thereby significantly enhancing the interfacial chemical bonding force.

[0060] Hot pressing pressure: 10-20MPa The main function of hot pressing pressure is to achieve full contact of interface molecules through mechanical compression and compact the composite layer into a continuous and uniform overall structure.

[0061] Hot pressing time: 5 to 10 minutes. The selection of hot pressing time needs to ensure that the interface reaction is fully completed, while avoiding thermal aging or performance degradation of the material due to too long a time.

[0062] Chemical reaction sufficiency mechanism: When the hot pressing time is 5 to 10 minutes, the dynamic cross-linking reaction and the formation of silicon-oxygen bonds can be fully carried out, so that the chemical bond formation in the dynamic reaction adhesion promotion layer is maximized, thereby providing the highest adhesion strength.

[0063] Preferably, the winding tension control range in S6 is 5 to 15N, and the winding speed is 100 to 150m / min.

[0064] Tension control range: 5~15N; Tension control is a key technical parameter in the winding process. The tension needs to be accurately maintained within the range of 5 to 15N to balance the mechanical properties of the film and the tightness of the winding.

[0065] Uniform tension distribution mechanism: Tension control can ensure the stretching consistency of the film in the entire width direction, and avoid film deflection or uneven winding caused by local tension differences.

[0066] Winding speed: 100~150m / min; The preferred range of winding speed is 100-150 m / min, which can match the production speed of the front-end extrusion co-extrusion and hot pressing curing, while avoiding process problems caused by too high or too low speed.

[0067] Mechanism matching production rhythm: After hot pressing and curing, the composite film is still in a certain thermoplastic state. A moderate winding speed allows the composite film to enter the winding process after completing curing and cooling, avoiding local thermal deformation of the film material caused by too fast speed.

[0068] Preferably, the nano-graphene oxide in the dynamic reaction adhesion promoting layer is treated with acid to introduce carboxyl groups or hydroxyl groups, and the functionalized silica is modified with a silane coupling agent to carry hydroxyl groups or amine groups.

[0069] Acid treatment of nanographene oxide (fGO) Nanographene oxide is oxidized with strong acid (nitric acid, sulfuric acid or a mixed acid) to generate a large number of carboxyl (-COOH) or hydroxyl (-OH) groups. The specific method is as follows: Disperse graphene oxide in concentrated nitric acid or sulfuric acid and stir to react for several hours; The residual acid is removed by multiple water washing and filtration to obtain graphene oxide modified with carboxyl or hydroxyl groups.

[0070] Surface polarization mechanism: Polar functional groups such as carboxyl (-COOH) and hydroxyl (-OH) are introduced on the carbon skeleton surface of graphene oxide through acidification. These polar groups can form hydrogen bonds or covalent bonds with polar groups (carbonyl, hydroxyl) on the molecular chains of polyurethane (PU) or polyvinyl alcohol (PVA) in the dynamic reactive adhesion promoting layer, thereby enhancing the interfacial chemical bonding force.

[0071] Enhanced dispersion: The introduction of carboxyl and hydroxyl groups improves the dispersibility of graphene oxide in the coating liquid, avoids its agglomeration in the coating layer, and ensures that the nanomaterials can be evenly distributed in the coating layer, thereby playing a reinforcing role.

[0072] Mechanical anchoring: The functionalized graphene oxide forms a microscopic embedded structure in the coating layer, which improves the coating layer's anti-peeling ability and interfacial adhesion strength through mechanical anchoring.

[0073] Silane coupling agent modification of functionalized silica (fSiO2) Functionalized silica is surface-modified by a silane coupling agent (γ-aminopropyltriethoxysilane or γ-aminopropyltrimethoxysilane) to have hydroxyl (-OH) or amine (-NH2) groups on its surface. The specific method is as follows: Adding nano-silica to an organic solvent (ethanol or methanol) containing a silane coupling agent; The reaction is heated and stirred under neutral or weak alkaline conditions for several hours, followed by filtering and drying to obtain surface-modified functionalized silica.

[0074] Chemical bonding enhancement mechanism: The alkoxy (ethoxy) part of the silane coupling agent undergoes a condensation reaction with the silanol (Si-OH) on the surface of silica to generate a stable Si-O-Si bond. At the same time, the other end (amine or hydroxyl) of the silane coupling agent is retained and can chemically bond (hydrogen bond or covalent bond) with the polyurethane or polyvinyl alcohol in the dynamic reaction adhesion promotion layer to further enhance the interfacial bonding force.

[0075] Interface bridging: The bifunctional characteristics of the silane coupling agent (one end is bonded to silica and the other end is bonded to the polymer) form a bridge structure between the nanoparticles and the polymer matrix, effectively improving the interfacial chemical bonding strength and mechanical properties.

[0076] Preferably, both the main film substrate and the secondary film substrate are corona treated, and the corona treatment parameters of the main film substrate are power 40-80W, treatment time 30-90 seconds, distance between electrode and substrate surface 5-10mm, and gas flow rate 20-50sccm; the corona treatment parameters of the secondary film substrate are consistent with those of the main film substrate.

[0077] Corona treatment of primary film substrate: The main film substrate is usually polyethylene (PE) or polypropylene (PP). Due to the low surface energy (usually 20-30 dyn / cm), it is difficult to achieve good interfacial adhesion when directly coated or compounded. Therefore, it is necessary to introduce polar groups on the surface through corona treatment to increase the surface energy and enhance its bonding with the dynamic reaction adhesion promoting layer.

[0078] Surface polarity enhancement: Corona treatment breaks the molecular chains on the surface of the substrate through high-voltage electric field discharge to generate free radicals. These free radicals are further oxidized in oxygen or air environment to form polar groups (hydroxyl-OH, carboxyl-COOH, peroxy-CO-OH). These polar groups form hydrogen bonds or chemical bonds with the polar components (polyurethane, polyvinyl alcohol) in the dynamic reaction adhesion promotion layer, thereby improving adhesion.

[0079] Surface roughening: During the corona discharge process, the substrate surface is bombarded by high-energy ions, forming a microscopic concave-convex structure. This surface roughening not only increases the physical contact area between the dynamic reaction adhesion promoting layer and the substrate, but also further enhances the interface bonding strength through mechanical interlocking.

[0080] Corona treatment of secondary film substrate: The secondary film substrate is also made of polyethylene (PE) or polypropylene (PP), and its surface treatment process and parameters are the same as those of the primary film substrate. After the secondary film substrate is treated with corona, the interfacial adhesion with the dynamic reaction adhesion promotion layer is enhanced, and at the same time, the delamination or peeling problem of the multi-layer composite film is avoided during subsequent use.

[0081] A laminating and laminating device based on the above cross-composite film production process comprises a first reverse unwinding mechanism and a laminating mechanism, wherein a feeding mechanism is installed on the right side of the first reverse unwinding mechanism, a first corona machine is installed on the top of the feeding mechanism, a printing and drying device is connected to the top of the first corona machine, a single extruder is installed on the top of the laminating mechanism, a second reverse unwinding mechanism is connected to the right side of the laminating mechanism, a second corona machine is installed between the laminating mechanism and the second reverse unwinding mechanism, a film cutting and powder spraying mechanism is connected to the right side of the second reverse unwinding mechanism, and a third reverse winding mechanism is connected to the right side of the film cutting and powder spraying mechanism. The first reverse unwinding mechanism of the device is used to release the main film substrate, and the reverse unwinding design ensures the tension stability of the film material during the unwinding process to avoid loosening or uneven tension of the coil. The feeding mechanism on the right cooperates with it to realize the smooth transmission of the film material and provide a stable input substrate for subsequent processing. The tension control during the unwinding and feeding process is completed by a precision sensor and a tension adjustment device. The first corona machine is installed on the top of the feeding mechanism, and is mainly used to perform surface pretreatment on the main film substrate to increase its surface polarity and surface energy. After the corona treatment, the printing and drying device prints functional patterns on the surface of the substrate and dries it quickly. The power, gas flow rate and treatment time of the corona treatment are precisely adjusted by the automatic control system to meet the treatment requirements of different substrates. The compounding mechanism is the core device of the equipment and is used in conjunction with the single extruder. The single extruder melts the dynamic reaction adhesion promotion layer at high temperature and evenly coats it on the surface of the main film substrate, while completing the extrusion co-extrusion compounding with the secondary film substrate. The compounding mechanism is equipped with a precise temperature, pressure and thickness control system to ensure the thickness uniformity and interface bonding force of the multi-layer composite film. A second reverse unwinding mechanism is installed on the right side of the compounding mechanism to release the secondary film substrate. The secondary film substrate is surface pre-treated by the second corona machine and then enters the compounding area to complete the co-extrusion compounding with the main film substrate. The design of the second corona machine is similar to that of the first corona machine, but the treatment parameters are optimized for the secondary film substrate to meet the surface treatment requirements of different materials. The composite film enters the film cutting and powder spraying mechanism, which is used to spray specific functional powders, anti-sticking powder or surface enhancer on the surface of the film material, and at the same time cut off the excess edge of the film material to ensure the consistency of the final film width. The powder spraying mechanism uses a precision nozzle to ensure uniform coverage of the powder. A third reverse winding mechanism is installed at the end of the equipment to roll the composite film into a coil. The winding mechanism has a precise tension control system, and the winding tension and speed can be adjusted to ensure the flatness and uniformity of the film during the winding process.

[0082] The present invention provides a laminating composite device and a cross-composite film production process, which have the following beneficial effects: 1. The present invention adopts the technical solution of corona treatment of both the primary film substrate and the secondary film substrate, introduces polar groups such as carboxyl and hydroxyl groups on the substrate surface, significantly improves the interfacial adhesion performance, and achieves the effect of high peel strength of the multilayer composite film. Compared with the solution of treating the substrate on one side in the prior art, it overcomes the problem of insufficient interfacial bonding strength and easy delamination of the multilayer film in high humidity and high temperature environment.

[0083] 2. The present invention adds acid-treated nano-graphene oxide and functionalized silicon dioxide modified with a silane coupling agent to the dynamic reaction adhesion promoting layer, so that the adhesion promoting layer has stronger chemical bonding ability and mechanical anchoring effect, thereby achieving the effect of improving adhesion and overall mechanical properties. Compared with the solution of directly using untreated nanomaterials in the prior art, the problem of uneven coating performance caused by nanomaterial agglomeration is solved.

[0084] 3. The present invention adopts dynamic cross-linking chemical technology and utilizes dihydroxybenzene and silane coupling agent in the dynamic reaction adhesion promotion layer to form a stable three-dimensional cross-linking network during the hot pressing curing process, thereby enhancing the interfacial bonding stability of the composite film. Compared with the traditional static adhesion layer, it solves the problem of decreased interfacial adhesion of the composite film under stress, and significantly improves the durability of the composite film under high-load use scenarios.

[0085] 4. The present invention optimizes the extrusion co-extrusion and winding process parameters to ensure that the primary substrate, the dynamic reaction adhesion promotion layer and the secondary substrate have good uniformity and stability during the interface bonding process. In particular, through the precise control of tension and speed, the composite film thickness is uniform and the interface is defect-free. Compared with the problem of uneven winding caused by tension fluctuations in the prior art, the applicability of the composite film in subsequent processing is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] Figure 1 It is a schematic diagram of the structure of the laminating composite equipment of the present invention; Figure 2 It is a schematic diagram of the production process of the cross composite membrane of the present invention.

[0087] Among them, 1. single extruder; 2. first reverse unwinding mechanism; 3. feeding mechanism; 4. printing and drying device; 5. compounding mechanism; 6. second reverse unwinding mechanism; 7. film cutting and powder spraying mechanism; 8. third reverse winding mechanism; 9. first corona machine; 10. second corona machine. DETAILED DESCRIPTION

[0088] The following will be combined with the drawings in the specification 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.

[0089] Embodiment 1: Corona treatment of main film substrate: Take a piece of polypropylene film (thickness 50μm) and place it in the corona treatment equipment. Adjust the equipment power to 50W, the gas flow rate to 30sccm, the distance between the electrode and the film surface to 7mm, and the treatment time to 60 seconds. After treatment, the surface energy of the film is increased from the original 28dyn / cm to 46dyn / cm.

[0090] Corona treatment of secondary film substrate: A polyethylene film (thickness 40μm) was also corona treated. The power was set to 60W, the gas flow rate was 45sccm, the electrode distance was 8mm, and the treatment time was 90 seconds. After treatment, the surface energy was increased to 48dyn / cm, and the surface microstructure was observed to form a uniform concave-convex distribution.

[0091] Dynamic Reactive Adhesion Promoter Coating: Prepare the coating solution: Dissolve 65 parts of polyurethane (PU) in a mixed solvent of ethanol / water (1:1) and stir until completely dissolved. Add 5 parts of γ-aminopropyltriethoxysilane, 3 parts of dihydroxybenzene, 4 parts of nanographene oxide (treated with nitric acid), and 6 parts of functionalized silica (modified with silane coupling agent). Continue stirring at 800rpm for 40 minutes to obtain a uniform dispersion. Use a knife coating process to apply the coating solution to the surface of the main film substrate with a coating amount of 0.3g / m 2 , coating thickness 1.2 μm. Subsequently, drying was performed at 80°C for 4 minutes.

[0092] Extrusion Coextrusion: In the extrusion equipment, the temperature of the main substrate was set at 200°C, the dynamic reaction adhesion promoting layer was 170°C, and the secondary substrate was 200°C. The extrusion speed was controlled at 120m / min and the pressure was adjusted to 25MPa. The compounding was completed through a multi-layer co-extrusion die.

[0093] Heat Press Curing: The composite film was sent to a hot press, the temperature was set to 140°C, the pressure was adjusted to 15 MPa, and the duration was 6 minutes. After completion, it was cooled to room temperature.

[0094] Rolling: The composite film passes through the tension control device, the tension is set to 10N, the winding speed is 130m / min, and the winding is completed.

[0095] Embodiment 2: Corona treatment of main film substrate: A polyethylene film (thickness 45μm) was selected, the power was set to 40W, the gas flow rate was 20sccm, the electrode distance was 6mm, and the treatment time was 40 seconds. After treatment, fine oxidation products appeared on the surface.

[0096] Corona treatment of secondary film substrate: A piece of polypropylene film (35 μm thick) was used, the power was adjusted to 70 W, the gas flow rate was 40 sccm, the electrode distance was 9 mm, and the treatment time was 70 seconds. The surface roughening effect was significant.

[0097] Dynamic Reactive Adhesion Promoter Coating: Prepare coating liquid: Dissolve 70 parts of polyvinyl alcohol (PVA) in 70°C water and stir until a transparent solution is obtained. Add 4 parts of γ-aminopropyltriethoxysilane, 3 parts of dihydroxybenzene, 5 parts of nanographene oxide (treated with nitric acid), and 7 parts of functionalized silica (modified with γ-aminopropyltriethoxysilane). Continue stirring at 700rpm for 50 minutes. Use a casting process to evenly spread the coating liquid onto the surface of the main film substrate, with a coating amount of 0.4g / m 2 , coating thickness 1.0 μm. Drying temperature was set at 90°C and time was 5 minutes.

[0098] Extrusion Coextrusion: The main film substrate, dynamic reaction adhesion promoting layer and secondary film substrate simultaneously enter the co-extrusion die head, the temperature of the main substrate is 195°C, the dynamic reaction layer is 180°C, and the secondary substrate is 190°C. The extrusion speed is 150m / min and the pressure is set to 30MPa.

[0099] Heat Press Curing: The temperature of the hot press was set to 130°C, the pressure was adjusted to 12 MPa, and the curing time was 8 minutes. Subsequently, the film was slowly cooled to room temperature.

[0100] Rolling: The winding tension was set to 8N and the speed was controlled at 140m / min. After winding, the inspection was completed and there was no warping or wrinkling.

[0101] Embodiment 3: Corona treatment of main film substrate: Take a polypropylene film (thickness 60μm), corona treatment power 50W, gas flow 35sccm, electrode and substrate distance 7mm, treatment time 60 seconds. The test surface energy is increased from 30dyn / cm to 45dyn / cm.

[0102] Corona treatment of secondary film substrate: The polyethylene film (thickness 55μm) was treated under the conditions of power 60W, gas flow 50sccm, distance 8mm, and treatment time 90 seconds. The surface roughening effect was significant after treatment.

[0103] Dynamic Reactive Adhesion Promoter Coating: Dissolve 60 parts of polyurethane in ethanol / water (1:1), add 6 parts of γ-aminopropyltriethoxysilane, 4 parts of dihydroxybenzene, 5 parts of acidified nanographene oxide, and 6 parts of functionalized silica modified with silane coupling agent. Stir at 800 rpm for 40 minutes to prepare a uniform coating liquid. Apply by knife coating, with a coating amount of 0.35 g / m 2 , thickness 1.2μm, drying conditions 80℃, 4 minutes.

[0104] Extrusion Coextrusion: The extrusion temperature was 205°C for the main substrate, 175°C for the dynamic reaction adhesion promoting layer, 200°C for the secondary substrate, 125m / min for the speed, and 25MPa for the pressure.

[0105] Heat Press Curing: The hot pressing temperature is 140°C, the pressure is 16 MPa, and the curing time is 5 minutes. After cooling, the treatment is completed.

[0106] Rolling: The tension is 12N, the speed is 130m / min, and there are no obvious defects on the film roll after winding.

[0107] Comparative Example 1: The main film substrate was not subjected to corona treatment: Based on the preparation process of Example 1, the corona treatment step of the main film substrate is not treated, and the other steps remain the same: The main film substrate was a polypropylene film (thickness 50 μm) without corona treatment, which was directly coated with a dynamic reactive adhesion promoting layer.

[0108] The process parameters such as the formulation of the dynamic reaction adhesion promoting layer, coating, extrusion co-extrusion, hot pressing curing, and winding are consistent with those in Example 1.

[0109] Comparative Example 2: The secondary film substrate was not subjected to corona treatment: Based on the preparation process of Example 1, the corona treatment step of the secondary film substrate is not performed, and the other steps remain the same: The main film substrate is still subjected to corona treatment, and the parameters are power 50W, gas flow rate 30sccm, electrode distance 7mm, and treatment time 60 seconds.

[0110] The secondary film substrate was a polyethylene film (thickness 40 μm) without corona treatment.

[0111] The preparation of the dynamic reaction adhesion promoting layer and the subsequent process flow remain the same as in Example 1.

[0112] Comparative Example 3: No functionalized nano-graphene oxide and functionalized silicon dioxide are used in the dynamic reaction adhesion promoting layer: Based on the preparation process of Example 1, nano graphene oxide and functionalized silicon dioxide were removed from the dynamic reaction adhesion promoting layer formula, and the remaining components and processes remained the same: The formula of the dynamic reaction adhesion promoting layer was changed to: 65 parts of polyurethane (PU), 5 parts of γ-aminopropyltriethoxysilane, 3 parts of dihydroxybenzene, and ethanol / water mixed solvent (1:1).

[0113] The process parameters of coating, extrusion co-extrusion, hot pressing curing and winding are consistent with those in Example 1.

[0114] Comparative Example 4: No functionalization of nanomaterials in the dynamic reaction adhesion promotion layer: Based on the preparation process of Example 1, unfunctionalized nano-graphene oxide and silicon dioxide are used in the dynamic reaction adhesion promoting layer, and the other steps remain the same: The formula of the dynamic reaction adhesion promoting layer was changed to: 65 parts of polyurethane (PU), 5 parts of γ-aminopropyltriethoxysilane, 3 parts of dihydroxybenzene, 4 parts of non-acidified nano-graphene oxide, and 6 parts of silicon dioxide not modified by a silane coupling agent.

[0115] The process parameters of coating, extrusion co-extrusion, hot pressing curing and winding are consistent with those in Example 1.

[0116] Comparative Example 5: Adjustment of the key component ratio in the dynamic reaction adhesion promoting layer: Based on the preparation process of Example 1, the component ratio of the dynamic reaction adhesion promoting layer was adjusted, and other processes remained the same: Reduce the amount of γ-aminopropyltriethoxysilane to 2 parts and the amount of dihydroxybenzene to 1 part.

[0117] The amount of nano-graphene oxide was increased to 8 parts, and the amount of functionalized silica was reduced to 3 parts.

[0118] The process parameters of coating, extrusion co-extrusion, hot pressing curing and winding are consistent with those in Example 1.

[0119] Comparative Example 6: Changes in hot pressing curing parameters: Based on the preparation process of Example 1, the parameters of hot pressing curing were adjusted, and the rest of the process remained the same: The hot pressing temperature was adjusted to 110°C, the pressure to 8 MPa, and the time to 3 minutes.

[0120] The remaining processes, including the corona treatment of the primary film substrate and the secondary film substrate, the coating of the dynamic reaction adhesion promoting layer and the extrusion co-extrusion process are consistent with those in Example 1.

[0121] Comparative Example 7: Winding tension and speed are not within the preferred range: Based on the preparation process of Example 1, the tension and speed of the winding process were adjusted, and the rest of the process remained the same: The winding tension was adjusted to 3N and the winding speed was adjusted to 180m / min.

[0122] The corona treatment of the primary film substrate and the secondary film substrate, the coating of the dynamic reaction adhesion promoting layer, the extrusion co-extrusion, and the hot pressing curing process are the same as those in Example 1.

[0123] Comparative Example 8: No corona treatment and no functionalized nanomaterial in the dynamic reaction adhesion promoting layer: Based on the preparation process of Example 1, combined with the adjustments of Comparative Examples 1 and 3: Neither the primary film substrate nor the secondary film substrate was corona treated.

[0124] Dynamic reactive adhesion promoting layer formulation for removal of nanographene oxide and functionalized silica.

[0125] The remaining coating, extrusion co-extrusion, hot pressing curing and winding processes are consistent with those in Example 1.

[0126] Experiment 1: Verify the effect of corona treatment on interfacial adhesion; Experimental purpose: By comparing the primary film substrate and the secondary film substrate with or without corona treatment, verify the role of corona treatment in improving interfacial adhesion performance.

[0127] Experimental materials and equipment: Materials: polypropylene film (primary film substrate, thickness 50 μm); polyethylene film (secondary film substrate, thickness 40 μm); dynamic reaction adhesion promoting coating liquid (formula of Example 1).

[0128] Equipment: corona treatment equipment, doctor blade equipment, multi-layer co-extrusion equipment, hot press, tensile testing machine.

[0129] Experimental process: Substrate treatment: Example 1: Both the primary film substrate and the secondary film substrate were subjected to corona treatment. The primary film corona parameters were power 50W, gas flow rate 30sccm, electrode distance 7mm, and treatment time 60 seconds; the secondary film corona parameters were power 60W, gas flow rate 45sccm, electrode distance 8mm, and treatment time 90 seconds.

[0130] Comparative Example 1: The main film was not subjected to corona treatment, and the remaining operations were consistent with those of Example 1.

[0131] Comparative Example 2: The secondary film was not subjected to corona treatment, and the remaining operations were consistent with those of Example 1.

[0132] Dynamic Reactive Adhesion Promoter Coating: The coating liquid was prepared according to the formula of Example 1. The coating liquid was evenly coated on the surface of the main film substrate by a knife coating process, and the coating amount was 0.3 g / m 2 , coating thickness 1.2μm.

[0133] After coating, the coating was dried at 80°C for 4 minutes.

[0134] Extrusion Coextrusion: The extrusion parameters of Example 1 were as follows: the temperature of the primary film substrate was 200° C., the temperature of the dynamic reaction adhesion promoting layer was 170° C., the temperature of the secondary film substrate was 200° C., the extrusion speed was 120 m / min, and the pressure was 25 MPa.

[0135] Heat Press Curing: The hot press temperature was 140°C, the pressure was 15 MPa, and the time was 6 minutes. After completion, it was cooled to room temperature.

[0136] Peel strength test: According to ASTM D1876, a composite film strip with a width of 15 mm was prepared. The maximum force required for peeling (N / 15 mm) was tested using a tensile testing machine at a speed of 100 mm / min.

[0137] Data Records: Each group of samples was tested 5 times and the average peel strength was calculated.

[0138] Experimental data: Table 1: Effects of different treatment methods on the peel strength of composite films: Sample No. Processing Peel strength (N / 15mm) Example 1-1 Both the primary film substrate and the secondary film substrate are corona treated 8.5 Example 1-2 Both the primary film substrate and the secondary film substrate are corona treated 8.2 Examples 1-3 Both the primary film substrate and the secondary film substrate are corona treated 8.4 Examples 1-4 Both the primary film substrate and the secondary film substrate are corona treated 8.7 Examples 1-5 Both the primary film substrate and the secondary film substrate are corona treated 8.6 Comparative Example 1-1 The primary film substrate is not corona treated, and the secondary film substrate is corona treated 4.1 Comparative Example 1-2 The primary film substrate is not corona treated, and the secondary film substrate is corona treated 3.9 Comparative Examples 1-3 The primary film substrate is not corona treated, and the secondary film substrate is corona treated 4.3 Comparative Examples 1-4 The primary film substrate is not corona treated, and the secondary film substrate is corona treated 4 Comparative Examples 1-5 The primary film substrate is not corona treated, and the secondary film substrate is corona treated 4.2 Comparative Example 2-1 The primary film substrate is corona treated, and the secondary film substrate is not corona treated 5.1 Comparative Example 2-2 The primary film substrate is corona treated, and the secondary film substrate is not corona treated 5.4 Comparative Examples 2-3 The primary film substrate is corona treated, and the secondary film substrate is not corona treated 5.3 Comparative Examples 2-4 The primary film substrate is corona treated, and the secondary film substrate is not corona treated 5.2 Comparative Examples 2-5 The primary film substrate is corona treated, and the secondary film substrate is not corona treated 5.5 The corona treatment significantly improved the surface polarity and roughness of the primary and secondary film substrates, and promoted the chemical and physical bonding of the dynamic reaction adhesion promoting layer with the substrate. The double-sided corona treatment (Example 1) showed higher interfacial bonding strength, while the untreated substrates (Comparative Examples 1 and 2) resulted in a significant decrease in peel strength. This demonstrates the key role of corona treatment in improving interfacial adhesion performance.

[0139] Experiment 2: Verify the effect of functionalized nanomaterials on coating performance: Purpose: The effect of functional treatment of nano-graphene oxide and functionalized silica in the dynamic reaction adhesion promoting layer on the dispersion of the coating layer and the interfacial adhesion properties of the composite film was investigated.

[0140] Experimental materials and equipment: Material: Nano-graphene oxide (acid-treated and untreated); functionalized silica (silane-modified and unmodified); polyurethane (PU); γ-aminopropyltriethoxysilane; dihydroxybenzene; ethanol / water mixed solvent (1:1).

[0141] Polypropylene film (thickness 50μm, primary film substrate); polyethylene film (thickness 40μm, secondary film substrate).

[0142] Equipment: Scanning electron microscope (SEM), doctor blade equipment, hot press, tensile testing machine.

[0143] Experimental process: Coating liquid preparation: Example

[0144] When preparing the coating solution, take 65 parts of polyurethane (PU) and dissolve it in ethanol / water (1:1), add 5 parts of γ-aminopropyltriethoxysilane, 3 parts of dihydroxybenzene, 4 parts of acid-treated nano-graphene oxide, and 6 parts of silane-modified functionalized silica, stir at 800 rpm for 40 minutes until evenly dispersed.

[0145] Comparative Example 3: Nano-graphene oxide and functionalized silica were not added to the formula, and the other components and stirring conditions remained the same.

[0146] Comparative Example 4: Unfunctionalized nano-graphene oxide and unsilane-modified silica were used in the formulation, and other formulations and stirring conditions remained the same.

[0147] Coating and drying: Use the scraper coating process to apply the coating liquid on the surface of the main film substrate with a coating amount of 0.3g / m 2 , coating thickness 1.2 μm, followed by drying at 80°C for 4 minutes.

[0148] Composite membrane preparation: The same extrusion co-extrusion and hot pressing curing process as in Example 1 was adopted (extrusion temperature: main film 200°C, secondary film 200°C, dynamic reaction adhesion layer 170°C, extrusion speed 120m / min, pressure 25MPa; hot pressing temperature 140°C, pressure 15MPa, time 6 minutes).

[0149] Testing and Characterization: Scanning electron microscopy (SEM) was used to observe the distribution of nanoparticles in the coating layer, focusing on whether they were evenly distributed and whether there was agglomeration.

[0150] The interfacial adhesion performance was evaluated using the ASTM D1876 standard peel strength test (same as the method in Experiment 1).

[0151] Experimental data: Table 2: Effect of functional nanomaterials on coating distribution and peel strength: Sample No. Functionalization state of nanomaterials SEM observation (distribution characteristics) Peel strength (N / 15mm) Example 1-1 Functionalization (acidification, silane modification) Evenly distributed, no obvious agglomeration 8.4 Example 1-2 Functionalization (acidification, silane modification) Basically uniform, with occasional small agglomerations 8.5 Comparative Example 3-1 No nanomaterials No nanoparticle distribution 4.2 Comparative Example 3-2 No nanomaterials No nanoparticle distribution 4.1 Comparative Example 4-1 Non-functional processing Severe agglomeration and uneven distribution 5.6 Comparative Example 4-2 Non-functional processing Large area reunion 5.4 Functionalized nano-graphene oxide and functionalized silicon dioxide significantly improve the dispersibility and interfacial bonding strength of the coating layer. The nanomaterials in the sample of Example 1 are evenly distributed and have the highest peel strength; in Comparative Examples 3 and 4, the unadded or unfunctionalized nanomaterials have a significant decrease in peel strength and coating performance due to particle agglomeration or lack of reinforcement. Functionalization is the core technology for improving the performance of the dynamic reaction adhesion layer.

[0152] Experiment 3: Verify the effect of coating liquid component ratio on adhesion performance: Purpose: Investigate the effect of the ratio of key components in the dynamic reaction adhesion promoting layer on the interfacial adhesion performance and mechanical properties of the coating layer.

[0153] Experimental materials and equipment: Material: Polyurethane (PU); γ-aminopropyltriethoxysilane; dihydroxybenzene; nanographene oxide (acid treated); functionalized silica (silane modified).

[0154] Polypropylene film (thickness 50μm, primary film substrate); polyethylene film (thickness 40μm, secondary film substrate).

[0155] Equipment: Dynamic Mechanical Analyzer (DMA), Tensile Testing Machine.

[0156] Experimental process: Coating liquid preparation: Example

[0157] The formula is 65 parts of polyurethane (PU), 5 parts of γ-aminopropyltriethoxysilane, 3 parts of dihydroxybenzene, 4 parts of acid-treated nanographene oxide, and 6 parts of functionalized silica. Each component is added to an ethanol / water mixed solvent (1:1) and stirred at 800 rpm for 40 minutes until it is completely dispersed.

[0158] Comparative Example 5: The formula ratio was adjusted to 65 parts of PU, 2 parts of γ-aminopropyltriethoxysilane, 1 part of dihydroxybenzene, 8 parts of nano-graphene oxide, and 3 parts of functionalized silicon dioxide. The remaining steps were the same as those in Example 1.

[0159] Coating and drying: Use the scraper coating process to evenly apply the coating liquid on the surface of the main film substrate, with a coating amount of 0.3g / m 2 , coating thickness 1.2μm. Drying temperature 80℃, time 4 minutes.

[0160] Composite membrane preparation: The main film substrate, coating layer, and secondary film substrate simultaneously enter the extrusion co-extrusion equipment, the main film substrate temperature is 200°C, the secondary film substrate temperature is 200°C, the dynamic reaction adhesion promotion layer temperature is 170°C, the extrusion speed is 120m / min, and the pressure is 25MPa. The composite film is prepared by hot pressing curing (temperature 140°C, pressure 15MPa, time 6 minutes).

[0161] Performance Test: Peel strength test (ASTM D1876): Same as the method in Experiment 1, test the peel strength of the composite film and record the maximum force value.

[0162] Dynamic Mechanical Analysis (DMA): The storage modulus (E') of the coating is tested on a DMA device to evaluate the elasticity and mechanical stability of the coating.

[0163] Experimental data: Table 3: Effect of the component ratio of the dynamic reaction adhesion promoting layer on adhesion performance and storage modulus: Sample No. Component ratio (key component adjustment) Peel strength (N / 15mm) Storage modulus E' (MPa) Example 1-1 γ-Silane 5 parts, dihydroxybenzene 3 parts, GO 4 parts, SiO2 6 parts 8.4 152 Example 1-2 γ-Silane 5 parts, dihydroxybenzene 3 parts, GO 4 parts, SiO2 6 parts 8.6 154 Comparative Example 5-1 γ-Silane 2 parts, dihydroxybenzene 1 part, GO 8 parts, SiO2 3 parts 6.1 96 Comparative Example 5-2 γ-Silane 2 parts, dihydroxybenzene 1 part, GO 8 parts, SiO2 3 parts 5.8 101 Optimizing the ratio of key components (γ-silane and dihydroxybenzene) is the key to improving the interfacial adhesion strength. The formula in Example 1 provides the best chemical bonding and dynamic crosslinking performance, while the reduction in the ratio of key components in Comparative Example 5 leads to a significant decrease in peel strength and storage modulus. Reasonable adjustment of the component ratio is the basis for optimizing adhesion performance.

[0164] Experiment 4: Verify the influence of hot pressing curing parameters on interfacial chemical reaction: Purpose: The effects of temperature, pressure and time of hot pressing curing on the sufficiency of interfacial chemical reaction and adhesion performance of composite membranes were studied, and the key role of hot pressing process on the dynamic reaction adhesion promoting layer was explored.

[0165] Experimental materials and equipment: Material: Primary film substrate (polypropylene, thickness 50 μm) and secondary film substrate (polyethylene, thickness 40 μm) after coating with dynamic reactive adhesion promoting layer.

[0166] Equipment: hot press, Fourier transform infrared spectrometer (FTIR), tensile testing machine.

[0167] Experimental process: Composite membrane preparation: Example 1: After the primary film substrate and the secondary film substrate were corona treated, a composite film was prepared according to the process of Example 1 (including coating liquid preparation, coating and drying).

[0168] Comparative Example 6: The preparation process is consistent with that of Example 1, except that the hot pressing process parameters are adjusted as follows: temperature 110°C, pressure 8 MPa, and time 3 minutes.

[0169] Heat Press Curing: Example 1: The hot pressing temperature was set to 140°C, the pressure was 15 MPa, and the time was 6 minutes.

[0170] Comparative Example 6: The hot pressing temperature was reduced to 110°C, the pressure was 8 MPa, and the time was 3 minutes. The other conditions remained the same.

[0171] Interface reaction test (FTIR): FTIR was used to detect the interfacial chemical reactions of the composite films, focusing on the characteristic absorption peaks of silicon-oxygen bonds (Si-O-Si) and dynamic cross-linked networks (the absorption peak of C=C bonds weakened and the peak of Si-O bond generation enhanced).

[0172] Peel strength test: The peel strength of the composite film was tested using the ASTM D1876 standard, and the maximum force value (N / 15 mm) was recorded.

[0173] Experimental data: Table 4: Effect of hot pressing parameters on interfacial chemical reaction and peel strength of composite films: Sample No. Hot pressing parameters FTIR characteristic peak changes Peel strength (N / 15mm) Example 1-1 140℃,15MPa,6min Si-O-Si peak is prominent, and C=C peak is weak 8.5 Example 1-2 140℃,15MPa,6min The interface reaction is sufficient and the cross-linking peak is enhanced 8.7 Comparative Example 6-1 110℃,8MPa,3min Si-O-Si peak is weak, and C=C peak remains obvious 4.6 Comparative Example 6-2 110℃,8MPa,3min The interfacial reaction is incomplete and the dynamic cross-linking peak is not significant. 4.8 The hot pressing temperature and pressure directly affect the sufficiency of the interfacial chemical reaction. In Example 1, under the optimized hot pressing parameters, the silicon-oxygen bonds and the dynamic cross-linking network are fully formed, and the peel strength is the highest; while in Comparative Example 6, the reaction is incomplete, resulting in a decrease in the interfacial bonding force. Appropriate hot pressing conditions are crucial for activating the interfacial chemical reaction and improving the adhesion of the composite film.

[0174] Experiment 5: Verify the influence of winding parameters on the uniformity and mechanical properties of composite films: Purpose: The effects of different winding tensions and speeds on the surface uniformity and overall mechanical properties of the composite film were analyzed, and the role of tension and speed matching on the final quality of the multilayer composite film was explored.

[0175] Experimental materials and equipment: Materials: The composite membrane prepared in Example 1.

[0176] Equipment: Winder, optical microscope (OM), tensile testing machine.

[0177] Experimental process: Winding parameter settings: Example 1: The winding tension is set to 10N and the speed is 130m / min.

[0178] Comparative Example 7: The winding tension was adjusted to 3N, the winding speed was increased to 180m / min, and the remaining steps were consistent with Example 1.

[0179] Sample preparation: After coating, extrusion co-extrusion and hot pressing curing are completed according to Example 1, the composite film is divided into two groups and subjected to different winding process treatments respectively.

[0180] Surface uniformity test: Use an optical microscope to observe the surface of the rolled composite film sample and record the wrinkles, wrinkles or local uneven areas on the film surface. Collect photos of random positions of the three samples for comparative analysis.

[0181] Mechanical properties test: The tensile strength of the composite film was tested according to ASTM D882: Prepare a test specimen with a width of 10 mm and a length of 100 mm and clamp it on a tensile testing machine; The specimen was stretched at a speed of 50 mm / min until it broke, and the maximum breaking strength was recorded.

[0182] Experimental data: Table 5: Effects of different winding parameters on the surface uniformity and mechanical properties of composite films: Sample No. Winding parameters Surface observation (wrinkles / unevenness) Tensile strength (MPa) Example 1-1 Tension 10N, speed 130m / min Smooth surface, few minor scratches 89 Example 1-2 Tension 10N, speed 130m / min Smooth without obvious defects 92 Comparative Example 7-1 Tension 3N, speed 180m / min Obvious wrinkles and many uneven areas 61 Comparative Example 7-2 Tension 3N, speed 180m / min Local wrinkles and broken edges 64 The reasonable tension and speed matching in Example 1 ensured the flatness and high tensile strength of the composite film surface; while in Comparative Example 7, due to insufficient tension and excessive speed, the film material was wrinkled and the mechanical properties decreased. The optimization of the winding process is of great significance for maintaining the overall quality and interface bonding strength of the composite film.

[0183] Experiment 6: Verification of the synergistic effect of dynamic reactive adhesion promoting layer and corona treatment: Purpose: By comparing different combinations of corona treatment and dynamic reaction adhesion promoting layer, the synergistic effect of the two on the interfacial adhesion properties and stability in wet and hot environments of the composite films was studied.

[0184] Experimental materials and equipment: Material: Dynamic reactive adhesion promoting layer (formulation of Example 1 and formulation with nanomaterial removed).

[0185] Primary film substrate (polypropylene, thickness 50 μm); secondary film substrate (polyethylene, thickness 40 μm).

[0186] Equipment: tensile testing machine, heat and humidity testing chamber.

[0187] Experimental process: Sample preparation: Example 1: Both the primary film substrate and the secondary film substrate are corona treated, and the dynamic reaction adhesion promoting layer formula contains functionalized nanomaterials.

[0188] Comparative Example 8: Both the primary film substrate and the secondary film substrate were not subjected to corona treatment, and the dynamic reaction adhesion promoting layer did not contain nanomaterials.

[0189] Coating and compounding: The dynamic reaction adhesion promoting layer is coated on the surface of the main film substrate with a coating amount of 0.3g / m 2 , coating thickness 1.2μm.

[0190] The main film substrate, coating layer and secondary film substrate simultaneously enter the extrusion co-extrusion equipment, the temperature of the main film substrate is 200°C, the dynamic reaction layer is 170°C, the secondary film substrate is 200°C, the extrusion speed is 120m / min, and the pressure is 25MPa.

[0191] Hot pressing curing conditions: temperature 140°C, pressure 15MPa, time 6 minutes.

[0192] Peel strength test (ASTM D1876): A composite film strip with a width of 15 mm was prepared, and the peel strength was tested using a tensile testing machine at a speed of 100 mm / min.

[0193] Damp heat aging test: Place the sample in a heat and humidity test chamber at 60°C and 95% relative humidity for 72 hours. Retest the peel strength after aging to evaluate the performance retention rate.

[0194] Experimental data: Table 6: Effect of the synergistic effect of corona treatment and dynamic reactive adhesion promoting layer on the properties of composite films: Sample No. Processing Initial peel strength (N / 15mm) Peel strength after wet heat (N / 15mm) Performance retention rate (%) Example 1-1 Corona + dynamic reaction layer (including functionalized nanomaterials) 8.5 7.9 92 Example 1-2 Corona + dynamic reaction layer (including functionalized nanomaterials) 8.7 8.1 93 Comparative Example 8-1 No corona + no functionalized nanomaterials 3.5 1.8 51 Comparative Example 8-2 No corona + no functionalized nanomaterials 3.6 1.9 53 The synergistic effect of corona treatment and dynamic reaction adhesion promotion layer significantly improved the interfacial adhesion performance and wet heat environment stability. The performance retention rate of the sample in Example 1 after wet heat was as high as 92%, while the lack of corona treatment and functionalized nanomaterials in Comparative Example 8 led to a significant decrease in interfacial bonding strength and durability. Synergistic optimization is the key to achieving high adhesion performance and environmental stability.

[0195] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cross composite membrane production process, characterized in that: The following steps are involved: S1. Surface pretreatment of the main film substrate; S2, preparing a dynamic reaction adhesion promoting layer coating liquid; S3, coating the dynamic reaction adhesion promoting layer onto the surface of the main film substrate; S4, multi-layering the primary film substrate, the dynamic reaction adhesion promoting layer and the secondary film substrate by an extrusion co-extrusion device; S5, subjecting the composite film to a heat-pressing curing treatment; S6, rolling up to obtain the finished product; The main film substrate includes 80-95% by weight of polyethylene or polypropylene, 3-10% by weight of maleic anhydride grafted polymer, and 0.5-2% by weight of processing aid; The dynamic reaction adhesion promoting layer comprises 60-80 mass parts of polyurethane or polyvinyl alcohol, 3-8 mass parts of γ-aminopropyltriethoxysilane, 2-5 mass parts of dihydroxybenzene, 3-6 mass parts of nanographene oxide, 4-8 mass parts of functionalized silicon dioxide and 10-20 mass parts of ethanol / water mixed solvent; The secondary film substrate comprises 80-95 weight percent of polyethylene or polypropylene, 3-10 weight percent of maleic anhydride grafted polymer, and 0.5-2 weight percent of processing aid.

2. A cross composite membrane production process according to claim 1, characterized in that: The method for surface pretreatment of the main film substrate in S1 includes low-temperature plasma treatment, and the treatment parameters are power 40-80W, treatment time 30-90 seconds, distance from the electrode 5-10mm, and gas flow rate 20-50sccm.

3. A cross composite membrane production process according to claim 1, characterized in that: The method for preparing the dynamic reaction adhesion promoting layer coating liquid in S2 comprises the following steps: Dissolving polyurethane or polyvinyl alcohol in an ethanol / water mixed solvent; adding γ-aminopropyltriethoxysilane, dihydroxybenzene, nanographene oxide and functionalized silica in sequence; The mixture is stirred at a stirring speed of 500 to 1000 rpm for 30 to 60 minutes to obtain a uniform dispersion.

4. A cross composite membrane production process according to claim 1, characterized in that: The method of coating the dynamic reaction adhesion promoting layer in S3 is a scraping or casting process, and the coating amount is 0.1-0.5 g / m 2 The coating thickness is 0.5-1.5 μm, the initial drying temperature is 70-100°C, and the drying time is 3-5 minutes.

5. A cross composite membrane production process according to claim 1, characterized in that: The parameters of the extrusion co-extrusion process in S4 are: the extrusion temperature of the main substrate layer is 190-250°C, the extrusion temperature of the interlayer is 150-200°C, the extrusion temperature of the secondary substrate layer is 190-250°C, the extrusion speed is 100-150m / min, and the pressure is 20-50MPa.

6. A cross composite membrane production process according to claim 1, characterized in that: The parameters of the hot pressing curing in S5 are as follows: the hot pressing temperature is 120-150° C., the pressure is 10-20 MPa, and the time is 5-10 minutes.

7. A cross composite membrane production process according to claim 1, characterized in that: The control range of the winding tension in S6 is 5-15N, and the winding speed is 100-150m / min.

8. A cross composite membrane production process according to claim 1, characterized in that: The nano graphene oxide in the dynamic reaction adhesion promotion layer is treated with acid to introduce carboxyl groups or hydroxyl groups, and the functionalized silicon dioxide is modified with a silane coupling agent to carry hydroxyl groups or amine groups.

9. A cross composite membrane production process according to claim 1, characterized in that: The main film substrate and the secondary film substrate are both corona treated. The corona treatment parameters of the main film substrate are power 40-80W, treatment time 30-90 seconds, distance between electrode and substrate surface 5-10mm, and gas flow rate 20-50sccm; the corona treatment parameters of the secondary film substrate are consistent with those of the main film substrate.

10. A laminating composite device based on the cross composite film production process according to claim 1, characterized in that: The invention comprises a first reverse unwinding mechanism (2) and a compounding mechanism (5), wherein a feeding mechanism (3) is installed on the right side of the first reverse unwinding mechanism (2), a first corona machine (9) is installed on the top of the feeding mechanism (3), a printing and drying device (4) is connected to the top of the first corona machine (9), a single extruder (1) is installed on the top of the compounding mechanism (5), a second reverse unwinding mechanism (6) is connected to the right side of the compounding mechanism (5), a second corona machine (10) is installed between the compounding mechanism (5) and the second reverse unwinding mechanism (6), a film cutting and powder spraying mechanism (7) is connected to the right side of the second reverse unwinding mechanism (6), and a third reverse winding mechanism (8) is connected to the right side of the film cutting and powder spraying mechanism (7).

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