A self-supporting optical cable with a highly corrosion-resistant and rodent-proof non-metallic optical unit.

Abstract

This invention relates to the field of optical cable manufacturing technology, and discloses a self-supporting optical cable with a high corrosion resistance and rodent-proof non-metallic optical unit. The cable includes: establishing a controllable interface by surface activation of the non-metallic optical unit; and, under strict constraints of this interface, setting process parameter windows for subsequent functional interface coating, curing, high-modulus rodent-proof material application, and sheath co-extrusion. This invention places the application of the high-modulus rodent-proof material before the high-temperature extrusion process of the sheath, utilizing it as a thermally stable internal skeleton to regulate the flow of the molten sheath material. This promotes the formation of a physically deeply coupled composite protective system around the skeleton during cooling and solidification of the sheath material. This results in mutual enhancement of corrosion resistance and physical damage resistance during the manufacturing process, improving the inherent protective uniformity and long-term service reliability of the optical cable.

Description

Technical Field

[0001] This invention relates to a self-supporting optical cable with a highly corrosion-resistant and rodent-proof non-metallic optical unit, belonging to the field of optical cable manufacturing technology. Background Technology

[0002] Currently, in diverse laying environments such as overhead or direct burial of pipelines, it is necessary to have both chemical corrosion resistance and physical protection against rodent damage. To this end, the industry usually adopts a functional layer separation design, that is, to achieve corrosion resistance by configuring a sheath of specific materials, and to provide physical protection by filling it with rigid materials such as fiberglass yarn or setting non-metallic reinforcements. This modular approach is clear in the design.

[0003] However, when such optical cables are placed in an environment with temperature and humidity changes and external stress for a long time, their inherent design problems will be exposed. The existing manufacturing method is to physically composite the functional layers, but the layers do not form a stable integrated structure. During service, the difference in thermal expansion and contraction coefficients between different material interfaces and the stress generated by the bending of the optical cable will cause micro-peeling between the layers. This peeling not only reduces the overall mechanical performance of the optical cable, but also creates gaps that form channels for moisture and corrosive media to penetrate, allowing the outer sheath to bypass its barrier function, directly leading to a reduction in the long-term service reliability of the optical cable.

[0004] To address the aforementioned issues, some direct improvement approaches also face new technical constraints. Specifically, existing technologies suffer from the following shortcomings: 1. Enhancing protection by increasing sheath thickness or upgrading material grades increases the outer diameter, weight, and rigidity of the optical cable, thereby increasing construction difficulty and material costs, and reducing the engineering application value of the solution; 2. Increasing the amount of high-modulus rodent-proof material filling the cable core can apply uncontrollable lateral stress to the internal optical fibers during cable manufacturing, winding, and laying, posing a risk of long-term degradation of optical fiber transmission attenuation. Therefore, the technical problem to be solved by this invention is how to design an optical cable manufacturing method that integrates the originally independent corrosion-resistant and rodent-proof structures into a tightly coupled, synergistic overall protective system during molding, thereby avoiding reliability issues caused by later structural delamination. Summary of the Invention

[0005] This invention provides a self-supporting optical cable with a highly corrosion-resistant and rodent-proof non-metallic optical unit. Its main purpose is to solve the problems of insufficient long-term reliability caused by the fact that the corrosion-resistant and rodent-proof functional layers are only physically composited in the existing optical cable manufacturing process, as well as the new constraints such as cost or performance degradation caused by existing reinforcement measures.

[0006] To achieve the above objectives, the present invention provides a self-supporting optical cable with a highly corrosion-resistant and rodent-proof non-metallic optical unit. The preparation of the optical cable includes the following steps:

[0007] Step a: Surface activation treatment is performed on the non-metallic optical unit to form an interface condition, wherein the density of surface polar groups of the non-metallic optical unit is within a preset first range.

[0008] Step b: Under the constraint of the interface, a functional interface coating is continuously coated, and the coating linear speed and coating temperature are controlled so that the coating rheological kinetic parameters determined by the coating linear speed and coating temperature are in the preset second range. The functional interface coating and the non-metallic optical unit surface form chemical bonds at the active sites defined in the first range.

[0009] Step c: Under the combined conditions of a preset traction tension and a preset drying endpoint moisture content, the non-metallic optical unit coated with a functional interface coating is cured.

[0010] Step d: According to the preset combination rules of wrapping angle and surface density, high modulus non-metallic rodent-proof material is applied to the outer surface of the cured non-metallic optical unit.

[0011] Step e involves co-extruding inner and outer sheaths and controlling the thickness ratio of the inner and outer sheaths to be within a preset third range. Steps a to e are executed sequentially. The interface premise provides a unique process window for determining the rheological dynamics parameters of the coating. This process window constructs a composite protection system in which the corrosion-resistant layer and the physical protective layer are deeply coupled at the interface.

[0012] Preferably, the surface activation treatment in step a is a high-energy physical surface modification treatment, the process parameters of which are set to open non-polar macromolecular chains and graft oxygen-containing polar groups on the inert surface of the non-metallic optical unit, thereby providing active sites for the chemical bonding of the functional interface coating in step b.

[0013] Preferably, the rheological kinetic parameters of the coating in step b are determined by the following relationship: ,in, For coating linear velocity, For coating temperature, The apparent rheological activation energy of functional interface coating materials. Let be the ideal gas constant. and These are empirical constants used to define the lower and upper limits of the second interval.

[0014] Preferably, the traction tension in step c is controlled within a preset tension range to orient the molecular chains within the functional interface coating during the curing process, while the moisture content at the drying endpoint is controlled below a preset threshold to maximize the density of the coating and eliminate internal micropores.

[0015] Preferably, in step d, the high-modulus non-metallic rodent-proof material is glass fiber yarn or aramid fiber yarn; the combination rules of the wrapping angle and the areal density are set to make the high-modulus non-metallic rodent-proof material form a mesh structure that can resist tangential biting force and buffer radial compressive stress.

[0016] Preferably, in step e, the inner and outer sheaths are co-extruded from different materials. The inner sheath material has high adhesion to high-modulus non-metallic rodent-proof materials, and the outer sheath material has high chemical corrosion resistance. The thickness ratio defined in the third interval is intended to achieve a functional gradient transition between the external chemical corrosion barrier and the internal physical stress skeleton.

[0017] Preferably, the functional interface coating in step b is a composite material containing epoxy resin or vinyl ester resin, and the composite material also contains a silane coupling agent for improving the interfacial bonding strength with the non-metallic optical unit.

[0018] Preferably, the high-modulus non-metallic rodent-proof material deployed in step d serves as a thermally stable internal skeleton during the high-temperature extrusion process of the sheath in step e, regulating the flow and cooling crystallization process of the molten sheath material, thereby inducing the formation of a dense sheath layer with consistent molecular orientation around the high-modulus non-metallic rodent-proof material.

[0019] Preferably, the method further includes: after completing steps a to e to obtain the formed non-metallic optical unit, the formed non-metallic optical unit is then used as an independent structural unit in the subsequent cable core stranding process, thereby separating the protective material laying process that affects the optical fiber performance from the cable forming process that introduces mechanical stress into the optical fiber.

[0020] Preferably, the method constructs an internally integrated coupling structure, so that the overall protective performance of the prepared optical cable is uniform along its length, and the protective performance is not degraded by the bending or twisting state of the optical cable during the laying process.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] 1. By placing the high-modulus non-metallic rodent-proof material in the high-temperature extrusion molding process of the optical cable sheath, the rodent-proof material serves as a thermally stable internal structural skeleton in subsequent processes. This regulates the flow of the molten sheath material, causing it to form a dense protective layer with highly consistent molecular orientation around the skeleton during cooling and solidification. This results in a composite protective system where the rodent-proof structure and corrosion-resistant sheath are physically deeply coupled. This preparation method changes the traditional process of simply physically superimposing protective functional layers, allowing corrosion resistance and resistance to physical damage to be mutually enhanced through the same manufacturing process. This avoids the technical limitations of compromising one property in pursuit of a single property.

[0023] 2. The molding of optical units containing optical fibers and integrated protective structures is set as an independent manufacturing stage. After this stage is completed, the molded optical units are then used as a whole in the subsequent core stranding process. This process path separates the protective material laying stage, which has a direct impact on optical fiber performance, from the cabling stage, which may introduce mechanical stress into the optical fiber. In this way, all mechanical stress in the core stranding and final sheath extrusion process is borne by the optical units that already have complete structure and protective capabilities, while the optical fiber itself is always in a stress-relieving environment. This approach avoids the potential risk of unpredictable micro-compression of the optical fiber by the protective filler during the molding process of complex structure optical cables from the source of the manufacturing process.

[0024] 3. The non-metallic optical cable produced by this method has corrosion resistance and rodent protection provided by the fixed structure built into the optical unit, rather than relying on the external armor layer. This makes the overall protective performance of the optical cable highly uniform along its length, and this performance does not change with the bending or twisting state of the optical cable. For application scenarios such as Integrated Access System (IMASS) optical cables that need to be laid in various complex and uncontrollable environments such as ducts, overhead, and direct burial, the inherent attitude-independent stability of this structure allows it to meet diverse deployment requirements with a single product specification. This simplifies the process of determining which type of optical cable is needed for different environments on-site, and reduces the overall cost of network construction and subsequent maintenance. Attached Figure Description

[0025] Figure 1 This is a process flow diagram of the fabrication process of the integrated protective optical unit of the present invention;

[0026] Figure 2 This is a graph showing the relationship between key surface activation parameters and performance in this invention.

[0027] Figure 3 This is a flowchart illustrating the process execution and quality inspection of the surface activation step in this invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in further detail below. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0029] This invention provides a self-supporting optical cable with a highly corrosion-resistant and rodent-proof non-metallic optical unit. It constructs a composite protection system with a deeply coupled protective functional layer at the interface. The core manufacturing process sequentially includes surface activation treatment of the non-metallic optical unit, continuous coating and curing of a functional interface coating, application of a high-modulus non-metallic rodent-proof material, and co-extrusion to form inner and outer sheaths. Through these sequentially executed process steps, the corrosion-resistant layer and the physical protective layer are integrated into a structurally and performance-synergistic whole during the manufacturing process. In optical cable manufacturing, the matrix material of the non-metallic optical unit is usually a polymer, whose surface is chemically inert and non-polar, making it difficult for subsequent functional coatings to form a firm adhesion. To address this technical problem, step a of this manufacturing method is configured to perform surface activation treatment on the non-metallic optical unit. This surface activation treatment is a high-energy physical surface modification treatment. For example, plasma bombardment or ultraviolet irradiation can be used. The process parameters, such as processing power and reaction time, are set to open non-polar macromolecular chains and graft oxygen-containing polar groups on the inert surface of the non-metallic optical unit, thereby providing a preset density of active sites for the chemical bonding of the subsequent functional interface coating. The result of this treatment is the formation of an interface prerequisite, which is that the surface polar group density of the non-metallic optical unit is within a preset first range. The basis for determining the first range is that when the polar group density is lower than the lower limit of the range, there are insufficient sites for subsequent chemical bonding, affecting the interfacial bonding strength. When the density is higher than the upper limit of the range, the surface of the substrate material may be degraded due to over-treatment, affecting its long-term stability. Therefore, by controlling the surface polar group density within the first range, step a provides a controllable and stable chemical bonding basis for the subsequent coating.

[0030] After obtaining a chemically active interface, the liquid functional interface coating material needs to be uniformly, densely, and defect-free coated onto the surface of the optical unit, achieving effective bonding with the active sites. Therefore, step b of this preparation method is set as follows: under the constraint of the interface, the functional interface coating is continuously coated, and the coating linear velocity and coating temperature are controlled so that the coating rheological kinetic parameters, determined by the coating linear velocity and coating temperature, are within a preset second range. The functional interface coating is a composite material containing epoxy resin or vinyl ester resin, and also contains a silane coupling agent to enhance the interfacial bonding strength with the non-metallic optical unit. The coating rheological kinetic parameters are determined by the following relationship: in, For coating linear velocity, For coating temperature, The apparent rheological activation energy of functional interface coating materials. Let be the ideal gas constant. and To define the lower and upper limits of the second interval using empirical constants, this relationship quantifies the flow behavior of the coating material during the coating process, where the coating linear velocity... The term represents the mechanical driving force applied to the coating, while the exponential term... This reflects the coating viscosity as a function of temperature. The degree of change, and the product of the two factors, jointly determine the flow state of the coating at the mold exit. The calibration procedure for the second interval is as follows: First, the viscosity of the specific functional interface coating material is measured at different temperatures using a rotational viscometer, and its apparent rheological activation energy is calculated. Subsequently, on the experimental coating line, the linear speed was systematically changed. and temperature The combination of these factors was used to test the thickness uniformity, surface defects, and bonding strength with the substrate of the corresponding produced coatings, and to screen out all qualified samples. Numerical values, and determine the minimum and maximum values ​​of these values ​​as and By establishing this process window, step b ensures that the functional interface coating forms a reliable chemical bond with the active sites defined in the first interval on the surface of the non-metallic optical unit.

[0031] After coating, the liquid coating needs to be transformed into a solid, dense protective layer. The microstructure of this process plays a decisive role in the final corrosion resistance. Therefore, step c of this preparation method is set as follows: under a preset combination of traction tension and preset drying endpoint moisture content, the non-metallic optical unit coated with the functional interface coating is cured. The traction tension is controlled within a preset tension range to orient the molecular chains within the functional interface coating during curing. Simultaneously, the drying endpoint moisture content is controlled below a preset threshold, such as 0.05%, to maximize the coating's density and eliminate internal micropores that may form due to moisture evaporation. This is achieved through the dual control of traction tension and final moisture content. In step c, the integrity and density of the formed corrosion-resistant layer in terms of physical structure are ensured. After constructing the corrosion-resistant layer, physical protection capabilities need to be integrated. To avoid introducing uncontrollable stress into the optical fiber using traditional filling methods, step d of this preparation method is set as follows: according to a preset combination rule of wrapping angle and areal density, a high-modulus non-metallic rodent-proof material is laid on the outer surface of the cured non-metallic optical unit. The high-modulus non-metallic rodent-proof material is glass fiber yarn or aramid fiber yarn. The combination rule of its wrapping angle and areal density is set to make the high-modulus non-metallic rodent-proof material form a mesh structure that can resist tangential biting force and buffer radial compressive stress. For example, a bidirectional spiral wrapping is used, and the wrapping angle is set to... to And control the areal density at to Within this range, this parameter combination can provide sufficient physical protection strength while forming a mesh skeleton with a certain porosity, providing space for the penetration and coupling of subsequent sheath materials.

[0032] Finally, the optical unit integrating the corrosion-resistant layer and rodent-proof skeleton needs to be encapsulated in the outer sheath to form a complete optical cable structure. To solve the problem of delamination caused by material thermal mismatch during long-term service due to the physical superposition of functional layers in traditional processes, step e of this preparation method is set as co-extruding to form inner and outer sheaths, and controlling the thickness ratio of the inner and outer sheaths to be within a preset third range. This step is carried out on the basis of step d, where the high-modulus non-metallic rodent-proof material is laid out and acts as a thermally stable internal skeleton during the high-temperature extrusion process of the sheath in step e. The flow and cooling crystallization process of the molten sheath material is regulated. Specifically, the inner and outer sheaths are co-extruded from different materials. The inner sheath material has high adhesion to the high-modulus non-metallic rodent-proof material, while the outer sheath material has high chemical corrosion resistance. During co-extrusion, the molten inner sheath material penetrates into the gaps in the mesh structure of the rodent-proof material and forms a physical anchor with the rodent-proof material upon cooling. The presence of a thermally stable internal skeleton induces the formation of a dense sheath layer with consistent molecular orientation around it. The third interval defines the inner and outer sheaths. The layer thickness ratio aims to achieve a functional gradient transition between the external chemical corrosion barrier and the internal physical stress framework. It should be noted that this preparation method also includes a process separation design. After completing steps a to e to obtain the shaped non-metallic optical unit, the shaped non-metallic optical unit is then used as an independent structural whole in the subsequent cable core stranding process. This process path separates the protective material laying stage, which affects the performance of the optical fiber, from the cabling stage, which may introduce mechanical stress into the optical fiber. In this way, all the mechanical stress in the cable core stranding and final optical cable sheath extrusion process is borne by the optical unit, which already has complete protective capabilities. The optical fiber itself is in a stress-relieving environment. This approach avoids the risk of unpredictable micro-compression of the optical fiber by the protective filler during the formation of complex optical cable structures. Finally, by constructing this inherent, integrated coupling structure, the overall protective performance of the optical cable prepared by this method is uniform along its length, and this performance does not deteriorate with the bending or twisting state of the optical cable during the laying process.

[0033] Meanwhile, self-supporting optical cable refers to a type of optical cable overall structure, specifically that the optical cable contains metal reinforcing components such as metal reinforcing cores or stranded wires. These metal components give the optical cable sufficient mechanical strength to withstand its own weight and additional loads such as wind and ice that may be encountered when laying it overhead. These are all extended implementation methods known to those skilled in the art.

[0034] Example 1: In a comprehensive access system network upgrade project in a coastal chemical industrial park, a fiber optic cable with both high corrosion resistance and rodent resistance needs to be laid. The environmental conditions in this area are characterized by high concentrations of salt spray in the air, soil containing various chemical residues, and frequent rodent activity. Previously deployed fiber optic cables with traditional multi-layer physical armor structures generally exhibited cracking of the outer sheath under the combined effects of temperature stress and chemical corrosion after 18 to 24 months of service, followed by armor corrosion. Moisture then seeped into the cable core through the gaps between the armor layer and the inner sheath, ultimately leading to increased fiber optic transmission attenuation exceeding the maintenance threshold. For this application scenario, the described preparation method was used to generate a highly corrosion-resistant and rodent-resistant non-metallic optical unit, which was then used to construct a new self-supporting fiber optic cable. The specific application process of this preparation method involves first performing surface activation treatment on the optical unit substrate to establish an interface prerequisite, providing a basis for the chemical bonding of the subsequent functional interface coating. This avoids the adhesion degradation that occurs in chemical atmospheres due to the reliance on physical adsorption in traditional coatings. Subsequently, when coating the functional interface coating, the coating rheological kinetic parameters are considered. The process is carried out within a defined window. The application of this parameter allows the coating to form chemical bonds with the active sites on the surface of the optical unit while its cured microstructure also achieves high density, forming an initial corrosion barrier without micropores.

[0035] Based on this, the method resolves the contradiction between enhanced protective performance and increased optical cable outer diameter and weight through the wrapping of high-modulus aramid fiber yarn in subsequent step d and the co-extrusion of inner and outer sheaths in step e. During the high-temperature extrusion process in step e, the pre-laid aramid fiber yarn mesh structure acts as a thermally stable internal skeleton, regulating the flow and cooling process of the molten inner high-adhesion sheath material. This promotes the sheath material to penetrate and form a physically deeply coupled composite system around the skeleton. This process transforms the problem of superimposing protective functional layers into the problem of forming an integrated protective structure. The aramid fiber yarn skeleton provides resistance to physical damage, while the tightly coupled inner and outer layers... The sheath provides a barrier against chemical corrosion, and there is no macroscopic physical interface between the two, thus eliminating the micro-peeling between layers caused by the difference in thermal expansion coefficients of different materials in traditional optical cables. The self-supporting optical cable prepared by this method was laid in pipelines and direct-buried routes in a chemical industrial park. After 36 months of continuous operation and monitoring, the optical fiber transmission attenuation on the optical cable line showed no observable change through periodic testing with an optical time domain reflectometer. Excavation and inspection of some sections revealed that the surface of the sheath of the extracted optical cable samples showed no cracks or swelling. Upon dissection, no delamination was observed between the internal aramid fiber yarn skeleton and the inner and outer sheaths. The optical unit structure was intact, and the internal optical fiber was in a stress-free state.

[0036] Example 2: To objectively verify the technical effect of the method claimed in this invention in improving the long-term reliability of optical cables, especially to verify the performance of its constructed composite protection system in suppressing interlayer peeling, an accelerated aging comparative test was conducted. The purpose of the test was to quantitatively compare the differences in fiber transmission performance and protective structure integrity between samples using the method of this invention and samples using traditional processes after undergoing simulated damp heat, salt spray, and mechanical stress cycles. Two sample groups were set up: a control group and the sample group of this invention. The control group consisted of non-metallic optical cables produced using traditional manufacturing processes. The structure involved physically filling glass fiber yarn into untreated optical units, followed by extruding a single-material sheath. The sample group of this invention consisted of self-supporting optical cables prepared strictly according to steps a to e in the specific implementation method. These cables had optical units that had undergone surface activation treatment and were coated with a functional interface coating, and inner and outer co-extruded sheaths deeply coupled with high-modulus aramid fiber yarn. The geometric dimensions, fiber type, and quantity of the two sample groups were consistent. The test platform was a programmable constant temperature and humidity test chamber with a temperature control range of [missing information]. to The accuracy is The test chamber also includes a salt spray corrosion test chamber. The optical performance monitoring equipment during the test is an optical time domain reflectometer with a measurement resolution of 0.01 dB.

[0037] The test procedure was as follows: two groups of samples were placed in the test environment simultaneously for a 1000-hour accelerated aging cycle test, with each cycle lasting 24 hours, including 16 hours of accelerated aging. to High and low temperature cycling, 4 hours of neutral salt spraying with a 5% sodium chloride solution, and 4 hours of dynamic bending with a bending radius 20 times the outer diameter of the optical cable were conducted. At the start of the test and at every 200-hour time point, the transmission attenuation of each sample group of optical fibers was tested, and the increment of the fiber relative to the initial value was recorded. After the test, the samples were dissected to observe the interface bonding state of their protective layer. Table 1 shows the performance data comparison at key time points during the test.

[0038]

[0039] Referring to Table 1, the experimental data shows that the fiber transmission attenuation of the control group increased from 400 hours, reaching an increase of 0.25 dB / km by 1000 hours. In contrast, the fiber transmission attenuation increase of the present invention remained below 0.02 dB / km throughout the entire experimental period. Dissection analysis after the experiment revealed severe delamination between the physically filled glass fiber yarn and the sheath in the control group sample, creating channels for moisture intrusion. This structural degradation was the cause of additional losses due to micro-bending of the optical fiber. In contrast, no delamination was found between the aramid fiber yarn skeleton and the co-extruded sheath in the sample of the present invention; the two maintained a structurally integrated composite whole. The experimental data indicates that the optical cable protection system prepared through a series of process steps, including surface activation, chemical bonding of functional interface coatings, and co-extrusion coupling of rodent-proof materials and the sheath, exhibits higher structural stability. Under simulated long-term harsh service conditions, this structure can effectively suppress interlayer delamination caused by material aging and stress mismatch, thereby protecting the transmission performance of the internal optical fiber from degradation.

[0040] To further verify the decisive role and non-obviousness of the technical concept in the present invention of placing the high-modulus non-metallic rodent-proof material before the high-temperature extrusion process of the sheath and using it as a thermally stable internal skeleton to regulate the molten sheath material, the following comparative example 1 is provided.

[0041] Comparative Example 1: This comparative example aims to simulate a modified conventional technical path that a person skilled in the art might adopt when facing the same technical problem. Compared with the sample group of the present invention in Example 2, this path uses the exact same non-metallic optical unit substrate, functional interface coating, high-modulus aramid fiber yarn, and inner and outer sheath materials, geometric dimensions, fiber type, and quantity. The essential difference lies in the way the sheath and rodent-proof material are combined. This comparative example does not use the integrated co-extrusion coupling process combining steps d and e of the present invention, but instead uses a more conventional stepwise physical composite process, that is, first extruding an inner sheath, then wrapping it with high-modulus aramid fiber yarn after cooling and solidification, and finally extruding the outer sheath. The specific preparation process is as follows: Similar to the sample group of the present invention, steps a, b, and c were performed on the non-metallic optical unit to obtain an optical unit coated and cured with a functional interface coating. Outside the optical unit, an inner sheath material with a thickness of 50% of the total thickness of the inner and outer sheaths was first extruded and allowed to cool and cure naturally. On the outer surface of the cured inner sheath, high-modulus aramid fiber yarn was wrapped according to the same wrapping angle and areal density combination rules as the sample group of the present invention. Finally, another outer sheath material with a thickness of 50% of the total thickness was extruded outside the aramid fiber yarn to form the final sample, referred to as Comparative Example 1. Comparative Example 1 and the sample group of the present invention were placed in the same accelerated aging test environment for 1000 hours of cyclic testing, and key performance data were recorded. The results are shown in Table 2.

[0042]

[0043] Post-experimental analysis revealed that although Comparative Example 1 appeared structurally compact initially, significant delamination occurred at the interface between the aramid fiber yarn layer and the inner and outer sheaths after hygrothermal and stress cycling. In the sample cross-section, the aramid fiber yarn could be easily separated from the inner and outer sheaths in its entirety using tweezers, indicating that the three layers only had simple physical contact and failed to form effective structural locking. This interface separation provided a channel for moisture intrusion, and during dynamic bending, the inability of each layer to cooperate in bearing force resulted in uneven micro-bending stress on the internal optical fiber, which was the direct cause of the significant increase in optical fiber transmission attenuation. The experimental results show that even using the exact same high-performance materials, simply replacing the integrated co-extrusion coupling process of this invention with a more conventional stepwise physical composite process in the art cannot solve the problem of interlayer delamination caused by thermal mismatch and mechanical stress between different materials, and cannot achieve long-term service reliability.

[0044] Example 3: This example combines Figures 1 to 3 This describes a self-supporting optical cable with a highly corrosion-resistant, rodent-proof, non-metallic optical unit, such as... Figure 1As shown, starting with a non-metallic optical unit, the process sequentially performs surface activation treatment in step a to form an interface, providing active sites for subsequent chemical bonding; functional interface coating in step b, where chemical bonding is formed at the active sites under interface constraints; curing treatment in step c to maximize coating density and eliminate internal micropores; laying high-modulus non-metallic rodent-proof material in step d to construct a mesh structure resistant to physical damage; and co-extrusion of inner and outer sheaths in step e, using the rodent-proof material as a skeleton to construct a deeply coupled composite protection system, thereby obtaining a formed non-metallic optical unit. This formed non-metallic optical unit participates as an independent whole in the subsequent cable core stranding process. This process separation design separates the protective material laying stage, which affects the performance of the optical fiber, from the cable forming stage, which introduces mechanical stress. The optical unit, which already has complete protection capabilities, bears the subsequent mechanical stress, thus avoiding the risk of unpredictable micro-squeezing of the optical fiber from the source.

[0045] like Figure 2 As shown, the horizontal axis represents the percentage of surface oxygen atoms (%), the left vertical axis represents the interfacial peel strength (MPa), and the right vertical axis represents the relative value of the matrix degradation degree. The solid curve in the figure shows that the interfacial peel strength increases with the increase of the percentage of surface oxygen atoms, reaching a peak of nearly 7.0 MPa at 12%, and then begins to decline. The dashed curve in the figure shows that the degree of matrix degradation begins to increase significantly after the percentage of surface oxygen atoms exceeds 10%. Considering both the interfacial peel strength and the stability of the matrix material, selecting a surface oxygen atom percentage range of 5% to 12% can ensure high interfacial bonding strength while avoiding significant matrix degradation.

[0046] like Figure 3 As shown, the operator first samples and checks the initial state of the non-metallic optical unit. After confirming that its surface wetting angle is greater than 90 degrees, the operator sets the processing parameters and confirms the power and duration. The optical unit is then sent into the processing chamber of the plasma equipment for radio frequency plasma bombardment. This process aims to open up the non-polar macromolecular chains and graft oxygen-containing polar groups. After the surface modification is completed, the surface is analyzed by an XPS detector to measure the percentage of oxygen atoms and obtain polar group density data. The quality control process uses this data to determine whether it falls within the first range of 5% to 12% of the target range. If the processing is qualified, the operator transfers the optical unit to the next process.

[0047] Example 4: On a newly built production line for manufacturing non-metallic optical units of specific specifications, to convert each preset process interval into an accurately executable production regulation, a standardized engineering calibration process needs to be carried out. The goal of this process is to systematically determine the specific numerical windows of all key process parameters in steps a to e for a given combination of non-metallic optical unit matrix materials, functional interface coating composite materials, high-modulus non-metallic anti-rat materials, and inner and outer sheath materials. This calibration process starts with the quantification of the surface activation treatment in step a. The initial state is an untreated non-metallic optical unit with a surface wetting angle greater than 90 degrees, showing hydrophobicity. The calibration equipment includes a radio frequency plasma processor and an X-ray photoelectron spectrometer. The process is to prepare multiple groups of optical unit samples. While keeping other parameters unchanged, only change the plasma treatment power and duration to form a parameter matrix. Subsequently, use the X-ray photoelectron spectrometer to analyze the percentage of oxygen atoms on the surface of each group of samples, and use this value as a quantification index for the density of surface polar groups. At the same time, conduct a coating adhesion peeling test on the samples after surface activation and subsequent coating curing, and record the interfacial peeling strength. The range of the percentage of oxygen atoms on the surface corresponding to the samples with a peeling strength greater than or equal to the preset reliability threshold is determined as the first interval. When the calibration result shows that the percentage of oxygen atoms on the surface is in the range of 5% to 12%, the interfacial peeling strength meets the requirements and there is no sign of matrix degradation. This 5% to 12% range is then solidified as the production control target for this material system.

[0048] Next, calibrate the coating rheodynamic parameters in step b, which aims to determine the upper and lower limit constants for this relational expression and the specific values of and the coating temperature . The calibration process is carried out on a pilot coating unit that allows independent and continuous adjustment of the coating line speed . First, measure the apparent rheological activation energy of this batch of functional interface coating materials using a laboratory rotational viscometer. Then, on the pilot coating unit, set a series of and combinations that cover the engineering application range. For each combination point, produce a section of optical unit samples, and use a laser diameter gauge and a surface defect vision detection system to evaluate the coating thickness uniformity and surface quality. Samples with a thickness fluctuation less than ±5% and no visible bubbles or shrink holes are judged as qualified. Record all the corresponding to the qualified samples, and calculate their values. The minimum and maximum values of the calculated values of all qualified samples are respectively determined as and This provides an operating window constrained by both linear velocity and temperature for mass production. For the curing process in step c and the wrapping process in step d, orthogonal experimental design is used to determine the parameter combination of traction tension, moisture content at the drying endpoint, wrapping angle, and areal density. In the experiment, these four parameters are used as factors, with three levels set for each factor, to prepare corresponding orthogonal experimental sample groups. For each sample group, after completing all preparation steps, radial extrusion tests and tangential shear tests are performed to quantify its physical protective performance. At the same time, the microscopic cross-section of its functional interface coating is observed using scanning electron microscopy to evaluate its density. Finally, through the analysis of the experimental results, the parameter combination that comprehensively affects various performance indicators to meet the design requirements is determined, and this set of parameters is set as the standard value in the production procedure. Finally, for step c... The thickness ratio of the inner and outer sheaths in step e, i.e., the third interval, was calibrated by preparing a series of samples. The total thickness of the inner high-adhesion sheath and the outer high chemical corrosion resistance sheath remained constant, but the thickness ratio of the two varied in 10% increments. These samples were immersed in a corrosive solution simulating a chemical environment and subjected to periodic bending stress. After the specified test cycle, the tensile strength retention rate of the samples was measured, and the bonding interface between the inner sheath and the aramid fiber yarn skeleton was observed. The thickness ratio range corresponding to the samples with a tensile strength retention rate of not less than 85% and no interface debonding was determined as the third interval. Through this series of systematic calibration procedures, the original process parameters were transformed into a set of data-supported and traceable engineering specifications, ensuring the performance uniformity and long-term service reliability of the final product.

[0049] Example 5: In the mass production process of optical cable manufacturing, in order to address the apparent rheological activation energy that may exist between different batches of functional interface coating composite materials. To address the differences, a standardized material introduction and process window validation procedure is implemented before the new batch of materials is officially used. This procedure aims to maintain the stability of the production process and the consistency of the final product performance without requiring a complete recalibration of the entire production line.

[0050] When a new batch of functional interface coating composite materials enters the production process, samples are first taken from this batch and tested using a temperature control system with an accuracy of [insert accuracy here]. A rotational viscometer was used to measure the viscosity of the material at multiple preset temperature points, and the apparent rheological activation energy of the batch was recalculated based on the measurement data. Then, this newly calculated Substitute the values ​​into the previously calibrated process window relationship. In the middle, a verification trial production was carried out. During the trial production, the coating linear speed was... With coating temperature The combination points are set at the lower limit, center, and upper limit of the original process window. Samples produced at these three combination points are tested for coating thickness, surface quality, and interfacial adhesion. If all test indicators fall within the acceptable range defined in the quality control specifications, the original process window parameters are confirmed. and This applies to new batches of materials that have been approved for production. If any indicator is detected to deviate from the specification boundary, adjustments will be made based on the deviation amount. or Fine-tuning is performed until all indicators of the verification sample return to the control center. This procedure is used to control the impact of raw material fluctuations on the performance of the final product in order to maintain the stability of the preparation method in an industrial production environment.

[0051] Example 6: Another specific application of the method of the present invention is to address the problem that batch-to-batch differences in the geometric dimensional tolerances or surface conditions of non-metallic optical unit substrate materials may affect the uniformity of subsequent functional interface coatings. To this end, when the production process is switched to a new batch of non-metallic optical unit substrate materials, a preliminary process adaptability verification procedure is performed in advance.

[0052] The procedure first randomly selects samples from the new batch of optical units and uses a laser diameter gauge with micron-level resolution to continuously measure the outer diameter and ellipticity at no fewer than 100 points to obtain the statistical distribution characteristics of the geometric dimensions of the batch of materials. Simultaneously, the initial surface energy is evaluated using a contact angle meter. If the measured mean geometric dimensions or surface energy values ​​show a systematic deviation exceeding a preset threshold (±0.5%) compared to the previous batch, a fine-tuning procedure for the process parameters is initiated. This fine-tuning procedure does not recalibrate the entire process window but, based on the established process model, only adjusts the coating linear velocity. or coating temperature Compensatory adjustments are made to offset the impact of substrate material variations on the coating's rheological behavior. The adjustment amount is determined based on a lookup table established in advance through experiments. This table links the offset of a specific geometric dimension or surface energy with the corresponding compensation value of the required process parameters. In this way, adaptation to raw material fluctuations is achieved without interrupting large-scale production, ensuring the consistency of protective performance between different batches of products.

[0053] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A self-supporting optical cable of a non-metallic optical unit against corrosion and rodents, characterized in that, The preparation of the optical cable comprises the following steps: Step a: surface activation treatment is performed on the non-metallic light unit to form an interface prerequisite, wherein the interface prerequisite is that the surface polarity group density of the non-metallic light unit is in a preset first interval; Step b: under the constraint of the interface prerequisite, a functional interface coating is continuously coated, and the coating line speed and the coating temperature are controlled so that the coating rheological kinetics parameter determined by the coating line speed and the coating temperature is in a preset second interval, and the functional interface coating and the non-metallic light unit surface form chemical bonding on the active sites defined in the first interval; Step c: curing treatment is performed on the non-metallic light unit coated with the functional interface coating under the combined condition of a preset traction tension and a preset drying end-point moisture content; Step d: high-modulus non-metallic rat-proof material is arranged on the outer surface of the cured non-metallic light unit according to a preset combination rule of wrapping angle and area density; Step e: inner and outer layer sheaths are formed by co-extrusion, and the thickness ratio of the inner and outer layer sheaths is controlled to be in a preset third interval; wherein steps a to e are sequentially performed, the interface prerequisite provides a unique process window for determination of the coating rheological kinetics parameter, and the process window is used to construct a composite protection system in which the corrosion-resistant layer and the physical protection layer are deeply coupled at the interface; The coating rheology kinetic parameters in step b are defined by the relationship: wherein, is the coating line speed, is the coating temperature, is the apparent rheological activation energy of the functional interface coating material, is the ideal gas constant, and are the lower and upper limit empirical constants defining the second interval; Step The pulling tension in the step is controlled within a preset tension interval to orient the molecular chains within the functional interface coating during the curing process, while the dry end point moisture content is controlled below a preset threshold to maximize the coating's density and eliminate internal micropores.

2. The self-supporting optical cable of claim 1, wherein, The surface activation treatment in step a is a high-energy physical surface modification treatment, and the process parameters are set to be able to open non-polar macromolecular chains on the inert surface of the non-metallic light unit and graft oxygen-containing polar groups, thereby providing active sites for chemical bonding of the functional interface coating in step b.

3. The self-supporting optical cable of claim 1, wherein the cable is a non-metallic optical cable that is resistant to corrosion and rodent damage, and is a high corrosion resistant rodent resistant non-metallic optical unit cable, characterized in that, The high-modulus non-metallic rat-proof material in step d is glass fiber yarn or aramid fiber yarn; the combination rule of wrapping angle and area density is set to form a network structure that can resist tangential biting force and buffer radial extrusion stress.

4. The self-supporting optical cable of claim 1, wherein, The inner and outer layer sheaths in step e are formed by co-extrusion of different materials, the inner layer sheath material has high adhesion to the high-modulus non-metallic rat-proof material, the outer layer sheath material has high chemical corrosion resistance, and the thickness ratio defined in the third interval aims to realize functional gradient transition between the external chemical corrosion barrier and the internal physical stress skeleton.

5. The self-supporting optical cable of claim 1, wherein the cable is a non-metallic optical cable that is resistant to corrosion and rodent damage, and is a high corrosion resistant rodent resistant non-metallic optical unit cable, characterized in that, The functional interface coating in step b is a composite material containing epoxy resin or vinyl ester resin, and the composite material further contains a silane coupling agent for improving the interfacial bonding strength of the non-metallic light unit.

6. The self-supporting optical cable of claim 1, wherein the cable is a high corrosion resistant rodent resistant non-metallic optical unit cable, characterized in that, The high-modulus non-metallic rat-proof material arranged in step d serves as a heat-stable internal skeleton during the sheath high-temperature extrusion process in step e, and regulates the flow and cooling crystallization process of the molten sheath material.

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