Polymer tube capping method for fiber electronic devices and fiber electronic device

Abstract

The application discloses a polymer pipe end sealing method of a fiber electronic device and the fiber electronic device. The polymer pipe end sealing method of the fiber electronic device comprises the following steps: providing a metal cap with a closed end, the inner wall of the metal cap defining an end sealing cavity with a cross-sectional area larger than that of a port of a polymer pipe to be sealed; filling the end sealing cavity with polymer powder of the same material as the polymer pipe; externally heating the metal cap, and stopping heating after the polymer powder is completely melted to form a polymer melt; after stopping heating, inserting the port of the polymer pipe into the polymer melt to a preset depth and keeping relative fixation before the polymer melt is cooled and solidified, so that the polymer melt wraps the port of the polymer pipe; and allowing the polymer melt to be cooled and solidified to be integrated with the port of the polymer pipe, thereby forming a polymer end sealing structure. The application realizes long-term and reliable sealing of the port of the polymer pipe of the fiber electronic device without causing thermal damage to the internal functional medium of the fiber electronic device.

Description

Technical Field

[0001] This application relates to the field of polymer tubing processing technology for fiber electronic devices, and more specifically, to a method for sealing polymer tubing for fiber electronic devices and a fiber electronic device. Background Technology

[0002] With the rapid development of flexible electronics and smart wearable technology, fiber optic electronic devices, such as fiber batteries, fiber sensors, and fiber energy storage devices, have become an important research direction. These products generally use thermoplastic polymer materials as the substrate tube to encapsulate and protect the internal functional media. The sealing performance of the polymer tube ends is crucial in determining the product's waterproof, oxygen-barrier, and leak-proof capabilities, directly affecting the long-term stable operation of the fiber optic electronic device and representing a core aspect of the entire manufacturing process.

[0003] Currently, thermofusion connection technology is commonly used in the field of water supply and drainage pipelines to achieve the connection and sealing of polymer pipes. This technology aims to prevent leakage of macroscopic fluids inside the pipeline and is suitable for working conditions with large pipe diameters (usually tens to hundreds of millimeters) and relatively stable operating environments (buried or indoor).

[0004] However, the technical requirements for polymer tubing end-sealing in the field of fiber optic electronic devices differ fundamentally from those in the field of water supply and drainage pipes, specifically in the following three aspects: First, the diameter of the polymer tubing used in fiber optic electronic devices is in the sub-millimeter to several millimeter range, far smaller than the conventional dimensions of water supply and drainage pipes. Second, fiber optic electronic devices internally encapsulate functional media such as electrode materials, electrolytes, and sensing elements. These media are extremely sensitive to trace amounts of water vapor and oxygen. If the port sealing is insufficient, the infiltration of air and water vapor will lead to device failure, short circuits, and severely affect service life. Third, in practical applications, fiber optic electronic devices must withstand dynamic operating conditions such as flexible bending, sweat corrosion, and repeated changes in temperature and humidity, and are required to maintain long-term stable sealing performance under these conditions. This is significantly different from the operating conditions of water supply and drainage pipes in stable underground or indoor environments.

[0005] Due to significant differences in dimensions, varying sealing performance requirements, and different applicable environments, the thermofusion connection technology for water supply and drainage pipes cannot be applied to the end sealing of polymer pipes in the field of fiber electronic devices.

[0006] Given the aforementioned differences, various sealing processes have been developed for polymer tubing in the field of fiber optic electronic devices. However, these processes generally suffer from common defects such as insufficient sealing reliability, low compatibility with different materials, and easy failure of the connection interface. The mainstream technical solutions are mainly divided into two categories: thermal fusion sealing and colloidal bonding sealing, as follows: 1) Thermal fusion sealing technology: Represented by the copper strip-assisted thermal fusion sealing process commonly used in the field of fiber batteries. This technology achieves sealing by heating and melting the tubing end with a heat-conducting medium. However, microscopic gaps are easily generated at the lead exit point, leading to water and oxygen penetration, which seriously affects the product's service life and stability. 2) Colloidal bonding sealing technology: This technology is further divided into epoxy resin potting and special sealing agent bonding. Chinese patent application CN107641489A discloses an epoxy resin potting compound for water treatment column membrane modules and its preparation method. This method discloses an epoxy resin potting compound for sealing the ends of pipes. However, using this epoxy resin potting compound to seal the pipe ends suffers from poor adhesive toughness, easy cracking, and weak adhesion to some polymer materials, making it difficult to guarantee long-term sealing reliability. Chinese patent CN101787047B discloses a phosphatidylcholine end-capping agent containing fluorocarbon chains and / or hydrocarbon chains with hydroxyl or amino groups at the ends, and polyurethane materials end-capped with it. This method uses a dedicated end-capping agent to seal the end faces of polyurethane, fluorine-based, and other polymer pipes. However, because the surface of polymer materials is usually inert, the bonding interface strength is insufficient, leading to problems such as delamination and water seepage during long-term use.

[0007] Therefore, the existing end-sealing solutions for polymer pipes are all difficult to ensure sealing reliability during long-term use and cannot be adapted to different polymer pipe materials. Summary of the Invention

[0008] The main objective of this application is to provide a method for sealing polymer tubing for fiber electronic devices and the fiber electronic device itself, in order to solve the technical problems of insufficient long-term sealing reliability, low adaptability to different polymer tubing materials, and easy failure of the connection interface in the prior art. This application achieves molecular-level sealing by melting and fusing polymer materials of the same material, and at the same time uses a metal cap as a heating container, molding die, and protective shell. Without causing thermal damage to the internal functional medium of the fiber electronic device, it achieves long-term reliable sealing of the port of any thermoplastic polymer tubing, and significantly improves the service life of the fiber electronic device.

[0009] To achieve the above objectives, this application provides the following technical solution: According to one aspect of this application, a method for sealing polymer tubing for fiber electronic devices is provided, comprising: Step S1: Provide a metal cap that is closed at one end, the inner wall of the metal cap defining a sealing cavity, the cross-sectional area of ​​the sealing cavity being larger than the cross-sectional area of ​​the polymer tube port to be sealed; Step S2: Fill the sealing cavity with polymer powder of the same material as the polymer tube; Step S3: Heat the metal cap from the outside until the polymer powder is completely melted in the sealing cavity to form a polymer melt, then stop heating; Step S4: After heating stops, before the polymer melt cools and solidifies, insert the polymer tube port into the polymer melt to a preset depth and keep it relatively fixed so that the polymer melt wraps around the outer wall and bottom of the polymer tube port; Step S5: Allow the polymer melt to cool and solidify, fusing it with the outer wall and bottom of the polymer tube port to form a polymer sealing structure; wherein, in the polymer sealing structure, the metal cap serves as an outer wrapping structure covering the outer periphery of the polymer sealing structure.

[0010] Preferably, the wall thickness of the metal cap is set to 0.1 mm to 0.3 mm.

[0011] Preferably, the gap between the inner wall of the metal cap and the outer wall of the polymer tube port is set to 1.4 mm to 1.6 mm.

[0012] Preferably, in step S2, the polymer powder is filled into the sealing cavity in multiple portions, and the metal cap is vibrated after each filling to expel the air between the polymer powder particles.

[0013] Preferably, in step S2, the end-sealing cavity is filled with the polymer powder so that the polymer melt formed after the polymer powder melts can completely encapsulate the polymer pipe end.

[0014] Preferably, in step S3, the temperature of heating the metal cap is set to be 30°C to 50°C higher than the melting temperature of the polymer powder.

[0015] Preferably, in step S4, the preset depth to which the polymer pipe port is inserted into the polymer melt is: a gap of 1 mm to 2 mm is left between the bottom of the polymer pipe port and the bottom of the sealing cavity.

[0016] Preferably, the depth of the sealing cavity is set to 2mm to 4mm.

[0017] Preferably, in step S4, the polymer tube end is coaxially aligned with the sealing cavity and inserted into the polymer melt at a uniform speed.

[0018] According to another aspect of this application, a fiber optic electronic device is provided, comprising a polymer tubing and a functional medium encapsulated within the polymer tubing; the port of the polymer tubing is sealed using the polymer tubing sealing method described above.

[0019] The technical solution provided in this application may include the following beneficial effects: (1) This application uses a polymer material of the same material as the polymer tubing as the encapsulation body, thereby eliminating the compatibility barrier between heterogeneous materials and adapting to various thermoplastic polymer tubings for fiber electronic devices. This application achieves broad compatibility with all fiber electronic devices encapsulated with polymer tubing, such as fiber batteries, fiber sensors, and fiber energy storage devices, thus broadening the application boundaries of the end-capping method of this application. (2) This application adopts a one-step sealing process, which eliminates the cumbersome pre-treatment (such as hot melt pre-sealing) and secondary sealing process in the traditional process. This application not only significantly improves the processing efficiency, but also greatly reduces the dependence on complex mass production equipment and manual operation, thereby effectively controlling the production cost and highly meeting the needs of industrialization and large-scale production. (3) This application replaces the traditional sealing method of polymer and metal with the principle of polymer melting and fusion of the same material, thus blocking the penetration channels of external water and oxygen from the physical structure. This application effectively overcomes the pain point of weak interface bonding of heterogeneous materials, significantly improves the bonding strength of the port, and thus greatly extends the service life of fiber electronic devices and enhances their sealing reliability in complex environments. (4) This application uses a metal cap as the core carrier of the sealing process. The metal cap has the following functions: First, as a heating container, the metal cap can achieve rapid and uniform heat conduction, efficiently transfer external heat to the inside of the sealing cavity, and ensure that the polymer powder melts as a whole in a short time; Second, the metal cap maintains structural rigidity and dimensional stability at high temperature, and can be used as a molding mold to constrain the shape of the molten polymer material, ensuring that the thickness of the sealing layer is uniform; Third, the metal cap is not removed after the sealing is completed. It serves as a protective shell for the sealing structure, forming a dense metal barrier layer, which effectively prevents external water vapor and oxygen from penetrating into the inside of the pipe port. (5) This application adopts an indirect heating method from the outside of the metal cap, rather than direct contact heating, which can achieve efficient and uniform heat conduction, effectively avoid the problem of insufficient melting caused by uneven heating, and at the same time avoid the high temperature being directly conducted to the inside of the pipe and causing thermal damage to the sensitive functional medium. (6) This application adopts the process sequence of "melting first, then inserting", that is, the polymer powder is completely melted to form a melt and then the heating is stopped, and then the polymer tube end is inserted into the polymer melt. This process effectively avoids the thermal damage of the functional medium (such as electrodes and electrolyte) encapsulated inside the polymer tube by high temperature, and ensures the safety of the sensitive components inside the fiber electronic device. (7) The polymer melt of this application wraps the outer wall and bottom of the polymer pipe end, achieving complete closure of the end face of the polymer pipe end and forming an effective long-term airtight seal. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings: Figure 1 This is a schematic diagram of a preferred embodiment of the metal cap in this application. Figure 2 This is a schematic diagram of another preferred embodiment of the metal cap in this application. Figure 3 This is a schematic diagram of the polymer tubing after end-sealing in an embodiment of this application; Figure 4 This is a cross-sectional schematic diagram of the polymer pipe end after sealing in an embodiment of this application; Figure 5 This is a schematic diagram of a preferred embodiment of the plug-in platform in this application. Figure 6 This is a schematic diagram of a preferred embodiment of the metal cap and the plug-in platform in this application. Figure 7 This is a schematic diagram of a preferred embodiment of the present application in which the polymer pipe port is coaxially aligned with the end-sealing cavity via a pipe positioning frame; Figure 8 This is a schematic diagram of a preferred embodiment of the pipe positioning frame in this application.

[0021] Explanation of reference numerals in the attached drawings: 1-Metal cap; 11-End sealing cavity; 2-Polymer tubing; 21-Port; 3-Connecting platform; 31-Positioning slot; 32-Mounting hole; 4-Polymer melt; 5-Tube positioning bracket; 51-Positioning hole; 52-Mounting leg; 6-Electrode tab. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be used interchangeably where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0025] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0026] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linked," and "socketing" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0027] This application provides a method for sealing polymer tubing for fiber optic electronic devices, comprising: Step S1: Provide a metal cap that is closed at one end, the inner wall of the metal cap defining a sealing cavity, the cross-sectional area of ​​the sealing cavity being larger than the cross-sectional area of ​​the polymer tube port to be sealed; Step S2: Fill the sealing cavity with polymer powder of the same material as the polymer tube; Step S3: Heat the metal cap from the outside until the polymer powder is completely melted in the sealing cavity to form a polymer melt, then stop heating; Step S4: After heating is stopped and before the polymer melt cools and solidifies, insert the polymer tube end into the polymer melt to a preset depth and keep it relatively fixed so that the polymer melt covers the outer wall and bottom of the polymer tube end; Step S5: Cool and solidify the polymer melt to fuse it with the outer wall and bottom of the polymer tube end to form a polymer end-cap structure. In the polymer end-capping structure, the metal cap serves as an outer wrapping structure covering the outer periphery of the polymer end-capping structure.

[0028] The following detailed description of a polymer tubing end-sealing method for a fiber electronic device according to this application is provided through specific embodiments.

[0029] like Figure 1 and Figure 2 As shown, in this embodiment, the metal cap 1 has a cylindrical structure that is closed at one end and open at the other. The inner wall of the metal cap 1 defines a sealing cavity 11, which is configured to accommodate polymer powder and allow the insertion of a polymer tube 2. The polymer powder is made of the same material as the polymer tube 2 to be sealed, so that after the polymer tube 2 is inserted into the sealing cavity 11, it can fuse and solidify with the molten polymer powder within the sealing cavity 11. Specifically, the opening of the metal cap 1 is connected to the sealing cavity 11, and the port 21 of the polymer tube 2 to be sealed extends into the sealing cavity 11 through the opening of the metal cap 1.

[0030] In practice, the shape of the metal cap 1 is adapted to the shape of the end of the polymer tube 2. In a preferred embodiment, such as... Figure 1 As shown, when the port 21 of the polymer tube 2 is cylindrical, the metal cap 1 adopts a corresponding cylindrical shape; in another embodiment, as... Figure 2 As shown, when the port of the polymer tube 2 is rectangular, the metal cap 1 adopts a matching rectangular cylindrical shape. It should be understood that the shape of the metal cap 1 is not limited to the above embodiment. Those skilled in the art can flexibly select or design a matching structural form of the metal cap 1 according to the actual shape of the port of the polymer tube 2.

[0031] In this embodiment, the material of the metal cap 1 includes, but is not limited to, metals such as copper, iron, or aluminum. Using a metal material to construct the sealing cavity 11 provides the following technical advantages: First, it achieves efficient and uniform heat conduction. Compared to polymer materials, metals have a higher thermal conductivity, enabling rapid and uniform transfer of external heat to the interior of the sealing cavity 11, ensuring that the polymer powder melts into a liquid state within a short time, effectively avoiding incomplete melting due to uneven heating. Second, it provides reliable high-temperature molding constraints. The metal cap 1 possesses excellent structural rigidity and dimensional stability at high temperatures. During the heating stage, it can act as a rigid mold to effectively constrain the molten polymer material, preventing it from flowing or collapsing. During the cooling stage, it precisely shapes the sealing layer, thereby ensuring the regularity and density of the sealing structure. Third, it forms a dense, protective barrier. The metal material itself has a dense and non-porous structure. After the end-sealing is formed, the metal cap 1 retains the outer wrapping structure as the end-sealing structure, which can effectively prevent external water vapor, oxygen and other substances from penetrating into the interior of the polymer pipe 2, and has the functions of heat insulation buffer and long-term sealing protection.

[0032] To achieve efficient and uniform heat conduction, ensuring that external heat can be quickly and evenly transferred to the interior of the sealing cavity 11, allowing the polymer powder to melt into a liquid state in a short time, in this embodiment, the wall thickness d1 of the metal cap 1 is preferably set to 0.1 mm to 0.3 mm. This wall thickness range has significant thermal advantages: the thinner the wall thickness of the metal cap 1, the lower its thermal resistance and the faster the heating response, thereby further promoting the rapid and uniform melting of the polymer powder.

[0033] In order to control the heat conduction distance and prevent high temperature from spreading outside the port and damaging sensitive structures such as electrodes and electrolyte inside the polymer pipe, in this embodiment, the effective depth of the sealing cavity 11 is preferably set to 2mm to 4mm.

[0034] In step S1, the cross-sectional area of ​​the sealing cavity is larger than the cross-sectional area of ​​the polymer tubing port to be sealed. This dimensional difference creates an annular gap between the inner wall of the metal cap 1 and the outer wall of the polymer tubing port 2. This gap is configured as a receiving space to hold the polymer melt and, upon cooling and solidification, provide a forming space for the resulting sealing layer.

[0035] The gap between the inner wall of the metal cap 1 and the outer wall of the port of the polymer pipe 2 directly determines the thickness of the sealing layer formed after the polymer melt solidifies and the integrity of the fusion interface, thus having a decisive impact on the overall sealing performance. If the gap is too small, not only will it not be able to accommodate enough polymer melt, but the melt flow will also be obstructed, making it difficult to fill the gap independently and evenly and completely wrap the outer wall of the pipe port, which will greatly increase the risk of sealing failure. Conversely, if the gap is too large, it will result in an excessive amount of polymer melt being accommodated, which is easily affected by gravity during the cooling and solidification process and flows downward and collapses, causing the upper half of the sealing layer of the polymer pipe port to be thin and the lower half to be severely accumulated, resulting in an uneven distribution of the sealing layer thickness.

[0036] In this embodiment, as Figure 4 As shown, the gap d2 between the inner wall of the metal cap 1 and the outer wall of the port of the polymer tube 2 is set to 1.4 mm to 1.6 mm, more preferably 1.5 mm. This size range allows for sufficient polymer melt to solidify and form a sealing layer that completely covers the outer wall of the polymer tube port 21 and the microscopic gaps at the junction of the metal tab 6 and the tube wall. At the same time, it provides free flow space to ensure that the polymer melt can autonomously and uniformly fill all gaps, guaranteeing uniform sealing layer thickness and the integrity of the fusion interface, ultimately achieving excellent sealing performance.

[0037] In step S2, when filling the sealing cavity with polymer powder of the same material as the polymer pipe, it is done in multiple stages, with the metal cap vibrated after each filling to expel air between the polymer powder particles. This "multiple filling with vibration" process effectively promotes the rearrangement of polymer powder particles and reduces particle gaps, fully filling the sealing cavity while facilitating gas expulsion. This process suppresses the generation of air bubbles inside the sealing layer from the source, thereby ensuring the compactness of the sealing structure and the overall sealing performance.

[0038] In this embodiment, the polymer tubing is made of materials including, but not limited to, FEP, PP, PE, or PTFE. The polymer powder of the same material as the polymer tubing means that the material of the filling polymer powder is consistent with the material of the polymer tubing to be sealed (for example, when the polymer tubing is FEP, the filling polymer powder is also FEP). The core advantage of using polymer powder of the same material is that it enables molecular-level fusion between the polymer tubing and the sealing layer, effectively avoiding delamination of the fusion interface due to material incompatibility during long-term use, thus fundamentally eliminating the risk of seal failure.

[0039] In step S2, when filling the end-sealing cavity with the polymer powder, the polymer powder is filled completely so that the polymer melt formed after the polymer powder melts can completely wrap the end of the polymer pipe.

[0040] In a preferred embodiment, the filling volume of the polymer powder is equal to the volume of the sealing cavity, meaning the sealing cavity is completely filled with polymer powder. Considering the characteristics of different polymer powder materials exhibiting volume shrinkage (e.g., FEP material) or volume expansion (e.g., PP material) after melting, this embodiment ensures a sufficient amount of molten polymer by filling the cavity with polymer powder before heating, thereby guaranteeing the successful formation of the sealing layer. Furthermore, even if a small amount of molten polymer overflows the sealing cavity due to molten expansion, it will not adversely affect the final sealing performance; the excess molten polymer can be removed through subsequent cleaning processes.

[0041] In step S3, the heating temperature of the metal cap is set to be 30°C to 50°C higher than the melting temperature of the polymer powder. The underlying principle is that when the polymer melt just reaches its melting temperature, its viscosity is high and its fluidity is poor, making it difficult to penetrate tiny gaps. However, when the heating temperature exceeds the melting temperature by 30°C to 50°C, the viscosity of the polymer melt decreases significantly, and its fluidity increases dramatically, enabling it to automatically fill the tiny gaps around the tab, thereby achieving molecular-level fusion between the polymer tube and the polymer melt.

[0042] Specifically, when the polymer pipe is FEP, its melting temperature is about 270°C, and the corresponding heating temperature is preferably 300°C to 320°C; when the polymer pipe is PP, its melting temperature is about 170°C, and the corresponding heating temperature is preferably 200°C to 220°C.

[0043] In step S3, the specific heating operation is as follows: the temperature of the heating platform is set to 30°C to 50°C above the melting temperature of the polymer powder, and then a metal cap filled with polymer powder and in an open state is placed on the heating platform. During the heating process, the melting state of the polymer powder is observed in real time, and the heating process is considered complete when it is completely melted and transformed into a polymer melt.

[0044] To determine whether a polymer powder has reached a fully molten state, it can be visually inspected to see if it exhibits a fluid or viscous state. It's important to note that fluid and viscous states are simply different physical forms exhibited by polymer powders of different materials after melting, influenced by the polymer chain structure. Both indicate that the gaps between the polymer powder particles have been completely eliminated, and a continuous, dense sealing layer can be formed after cooling. This is not directly related to whether the heating was sufficient. If it has not reached the above state and remains in a dry powder state, it indicates the presence of numerous pores and gaps between the particles. After sealing, these easily form channels for water vapor and oxygen to permeate, leading to seal failure.

[0045] Specifically, if any of the following situations are observed during the heating process, it is determined that the polymer powder has not completely melted and heating needs to continue: First, the polymer powder still maintains a distinct particle state, with clear boundaries and is loose and non-adhesive, and the powder inside can still flow freely when the metal cap is shaken; Second, a bright melt film has not formed on the surface of the powder, with only a small number of local particles being slightly sticky, and the whole does not show any clumping or flattening phenomenon; Third, when the polymer tube is inserted, the polymer powder cannot evenly cover the outer wall of the tube, or is even directly pushed away by the tube, resulting in obvious gaps between the two.

[0046] In this embodiment, a digital display constant temperature heating platform can be selected, with a temperature control range typically from room temperature to 350℃, which can meet the heating requirements of this embodiment. This heating platform usually employs PID intelligent temperature control technology, achieving a temperature control accuracy of ±1℃ or even higher. This high-precision constant temperature control helps ensure uniform heating of the polymer powder, avoiding abnormal viscosity of the polymer melt or localized overheating due to temperature fluctuations. Furthermore, the heating platform panel is mostly made of aluminum alloy with internal stainless steel heating tubes, featuring high thermal conductivity, rapid heating, and uniform heating, ensuring consistent heating of the metal cap placed on it, thereby promoting the rapid and complete melting of the polymer powder. It should be noted that the above heating platform is only an exemplary selection; those skilled in the art can also select other heating equipment that can meet the heating requirements of this embodiment according to actual process needs.

[0047] Once the polymer powder has completely melted to form a polymer melt, heating of the metal cap is stopped, and it is transferred from the heating platform to the insertion platform, where the polymer pipe end and the polymer melt are fused at the molecular level.

[0048] In step S4, when inserting the polymer tube end into the polymer melt, it is necessary to ensure that the polymer tube end and the sealing cavity are coaxially aligned. This coaxial alignment ensures that the gap between the inner wall of the metal cap 1 and the outer wall of the polymer tube end 2 is evenly distributed, thereby ensuring that the sealing layer formed after the polymer melt cools and solidifies is of uniform thickness and completely covers the polymer tube end.

[0049] In a preferred embodiment, such as Figure 5 and Figure 6 As shown, the insertion platform 3 has multiple positioning slots 31 for supporting and positioning the metal cap 1. When the metal cap 1 is cylindrical, the positioning slots 31 are circular slots that fit it, and the outer diameter of the metal cap 1 matches the inner diameter of the positioning slots 31, thereby achieving axial positioning of the metal cap 1. In another embodiment, as long as the shape and size of the positioning slots 31 are adapted to the metal cap 1, axial positioning of the metal cap can be achieved. In addition, the depth of the positioning slots 31 is less than the height of the metal cap 1, so that the operator can easily pick up and put down the metal cap 1 during the insertion process.

[0050] like Figure 5 and Figure 8 As shown, the connector 3 has mounting holes 32, and the pipe positioning bracket 5 has mounting legs 52 that are adapted to the mounting holes 32. Figure 6 and Figure 7 As shown, after transferring the metal cap 1 containing the polymer melt 4 to the insertion platform 3, the mounting leg 52 is inserted into the mounting hole 32, thus securely installing the pipe positioning bracket 5 onto the insertion platform 3. Figure 8 As shown, the pipe positioning frame 5 has a positioning hole 51. When the pipe positioning frame 5 is installed in place, the positioning hole 51 coincides with the central axis of the positioning slot hole 31 on the insertion platform 3. At this time, the inner diameter of the positioning hole 51 matches the outer diameter of the polymer pipe 2, and the polymer pipe 2 is accurately inserted into the polymer melt 4 through the positioning hole 51, thereby achieving coaxial alignment between the end of the polymer pipe 2 and the sealing cavity.

[0051] In another embodiment, the pipe positioning bracket 5 can be omitted, and the polymer pipe 2 can be inserted into the polymer melt 4 by hand. As long as basic coaxial alignment can be achieved, ensuring that the polymer melt completely covers the port of the polymer pipe, and thus guaranteeing the final sealing performance, this is acceptable.

[0052] In step S4, when inserting the polymer tube end into the polymer melt, it must be done vertically and at a uniform speed. Specifically, maintaining a vertical and uniform insertion speed effectively prevents the polymer tube from tilting or being inserted too quickly, which could trap air into the polymer melt and form bubbles. Simultaneously, the insertion speed should be controlled within a reasonable range: if the speed is too slow, the polymer melt may cool and solidify prematurely before the polymer tube is fully inserted; if the speed is too fast, a large amount of polymer melt will overflow, preventing the polymer tube end from being fully enveloped by the polymer melt. All of the above procedures aim to ensure that the sealing layer completely encapsulates the polymer tube end without air bubbles, thereby ensuring the final sealing performance.

[0053] Regarding the above-mentioned operation method, in a preferred embodiment, the verticality of the insertion process can be ensured by the pipe positioning frame 5, and the downward pressing speed of the pipe can be precisely controlled by a linear drive mechanism (such as a motor-driven lead screw assembly) to achieve uniform insertion. In another embodiment, the pipe positioning frame 5 and the linear drive mechanism can be omitted, and the insertion action can be completed manually; as long as the manual operation can ensure basic verticality and uniformity, and effectively avoid air bubble entrapment and polymer melt overflow, the sealing performance requirements can be met.

[0054] In step S4, the polymer tube end needs to be inserted into the polymer melt before it naturally cools and solidifies. In this embodiment, natural cooling refers to cooling in a static environment without the aid of cooling equipment. The natural cooling and solidification time of polymer materials is affected by their own material properties. For example, the solidification start time of FEP material is about 10 to 15 seconds, while that of PP material is about 20 to 25 seconds. In actual operation, it is necessary to ensure that the insertion of the polymer tube is completed before the above-mentioned solidification start time to ensure that the polymer melt is in a good flow state, thereby achieving full encapsulation and molecular-level fusion of the polymer melt with the polymer tube end.

[0055] In step S4, the polymer pipe end is inserted into the polymer melt to a predetermined depth, such that a gap d3 is formed between the bottom of the pipe end and the bottom of the sealing cavity (e.g., ...). Figure 4 As shown in the figure, the gap d3 is preferably 1 mm to 2 mm. The gap d3 is designed to provide space for the polymer melt to accommodate and flow: on the one hand, it ensures that a sufficient amount of polymer melt solidifies to form a complete bottom sealing layer; on the other hand, it ensures that the polymer melt can fill the gap autonomously and uniformly, thereby ensuring the consistent thickness of the sealing layer and the integrity of the fusion interface, and ultimately achieving excellent sealing performance.

[0056] If the gap between the bottom of the polymer pipe port and the bottom of the sealing cavity is too small or nonexistent, the following two defects will occur: First, the polymer melt in the gap will be excessively compressed, which will easily cause the polymer melt to flow to the periphery of the port or fail to fill effectively. After cooling, it will form material-deficient bubbles or hollow gaps inside the bottom sealing layer, which will then become water and oxygen permeation channels, destroying the integrity of the seal. Second, the lack of polymer melt buffer space at the bottom will easily lead to excessive heat concentration, thereby causing thermal damage to the functional medium inside the polymer pipe.

[0057] To ensure a 1mm to 2mm gap between the bottom of the polymer pipe port and the bottom of the end cap cavity, a marking and limiting method can be used: First, measure the actual depth of the metal cap end cap cavity, subtract 1mm to 2mm from it to obtain the target insertion depth, and mark the limiting line at the insertion end of the polymer pipe; during insertion, stop pushing when the limiting line reaches the opening end of the metal cap, thereby accurately ensuring the size of the reserved space at the bottom.

[0058] Furthermore, this application also provides a fiber optic electronic device. This fiber optic electronic device includes a polymer tubing and a functional medium encapsulated within the polymer tubing. The ends of the polymer tubing are sealed using the aforementioned polymer tubing end-sealing method, which will not be elaborated further here.

[0059] In a preferred embodiment, the fiber electronic device is a fiber lithium-ion battery. The fiber lithium-ion battery includes a polymer tubing and a functional medium encapsulated within the polymer tubing. Specifically, both ends of the polymer tubing of the fiber lithium-ion battery have ports, and both ports are sealed using the aforementioned polymer tubing end-sealing method. This sealing structure effectively prevents the intrusion of water and oxygen from the external environment, thereby significantly improving the battery's lifespan.

[0060] In another embodiment, the fiber optic electronic device can also be a fiber sensor or a fiber energy storage device. Such fiber optic electronic devices also use polymer tubing to encapsulate the internal functional medium, and the ports of the polymer tubing can be sealed using the aforementioned polymer tubing end-sealing method.

[0061] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for sealing polymer tubing for fiber optic electronic devices, characterized in that, include: Step S1: Provide a metal cap that is closed at one end, the inner wall of the metal cap defining a sealing cavity, the cross-sectional area of ​​the sealing cavity being larger than the cross-sectional area of ​​the polymer tube end to be sealed; Step S2: Fill the sealing cavity with polymer powder of the same material as the polymer tube; Step S3: Heat the metal cap from the outside until the polymer powder is completely melted in the sealing cavity to form a polymer melt, then stop heating; Step S4: After heating is stopped and before the polymer melt cools and solidifies, insert the polymer tube end into the polymer melt to a preset depth and keep it relatively fixed so that the polymer melt covers the outer wall and bottom of the polymer tube end; Step S5: Cool and solidify the polymer melt, and fuse it with the outer wall and bottom of the polymer pipe end to form a polymer end-cap structure. In the polymer end-capping structure, the metal cap serves as an outer wrapping structure covering the outer periphery of the polymer end-capping structure.

2. The method for sealing polymer tubing for fiber electronic devices according to claim 1, characterized in that, The wall thickness of the metal cap is set to be between 0.1 mm and 0.3 mm.

3. The method for sealing polymer tubing for fiber electronic devices according to claim 1, characterized in that, The gap between the inner wall of the metal cap and the outer wall of the polymer pipe port is set to 1.4 mm to 1.6 mm.

4. The method for sealing polymer tubing for fiber electronic devices according to claim 1, characterized in that, In step S2, the polymer powder is filled into the sealing cavity in multiple portions, and the metal cap is vibrated after each filling to expel the air between the polymer powder particles.

5. The method for sealing polymer tubing for fiber electronic devices according to claim 1, characterized in that, In step S2, the end-sealing cavity is filled with the polymer powder so that the polymer melt formed after the polymer powder melts can completely cover the polymer pipe end.

6. The method for sealing polymer tubing for fiber electronic devices according to claim 1, characterized in that, In step S3, the temperature of heating the metal cap is set to be 30°C to 50°C higher than the melting temperature of the polymer powder.

7. The method for sealing polymer tubing for fiber electronic devices according to claim 1, characterized in that, In step S4, the preset depth to which the polymer pipe port is inserted into the polymer melt is: a gap of 1 mm to 2 mm is left between the bottom of the polymer pipe port and the bottom of the sealing cavity.

8. The method for sealing polymer tubing for fiber electronic devices according to claim 1, characterized in that, In step S4, the port of the polymer tube is coaxially aligned with the sealing cavity and inserted into the polymer melt at a uniform speed.

9. The method for sealing polymer tubing for fiber electronic devices according to claim 1, characterized in that, The depth of the sealing cavity is set to 2mm to 4mm.

10. A fiber optic electronic device, characterized in that, It includes a polymer tubing and a functional medium encapsulated inside the polymer tubing; the port of the polymer tubing is sealed using the polymer tubing sealing method as described in any one of claims 1 to 9.

Images