Disposable cross-section watertight optical fiber for ocean exploration and preparation method of disposable cross-section watertight optical fiber

Abstract

The invention belongs to the technical field of optical fibers, and particularly relates to a disposable cross-section watertight optical fiber for ocean exploration and a preparation method, the disposable cross-section watertight optical fiber for ocean exploration comprises an optical fiber core, a filling rope insulating tape, a double-sided plastic-steel-coated belt and a polyethylene cable outer sheath, and the filling rope insulating tape, the double-sided plastic-steel-coated belt and the polyethylene cable outer sheath are sequentially arranged on the outer layer of the optical fiber core; the surface of the optical fiber core is coated with a transparent material cladding with low refractive index; composite modified vulcanized polyurethane grouting is filled between the optical fiber core and the filling rope insulating tape; the optical cable has the advantages that the polyethylene optical cable outer sheath made of the polyvinyl chloride outer layer material and the super-amphiphobic coating material is combined, and the filling rope insulating tape and the double-sided plastic-steel-covered tape are added in the optical cable, so that the bending resistance and the watertight performance of the optical cable are enhanced, and the optical signal communication transmission performance of the optical fiber with the damaged cross section is guaranteed; therefore, the cut optical cable can still be used as a sensing carrier for temperature rise, vibration, strain and the like underwater.

Description

Technical Field

[0001] The present application belongs to the field of optical fiber technology, and specifically relates to a disposable broken-section watertight optical fiber for ocean detection and a preparation method thereof. Background Art

[0002] Due to the extremely harsh deep-sea environment, factors such as huge water pressure, low temperature, and scarce light limit human direct observation of the deep sea. Therefore, deep-sea exploration often relies on technical means such as photoelectric sensors, underwater robots, seabed foundations, and optical cable communications. When conducting deep-sea exploration, optical fiber is the main carrier of long-distance real-time information transmission media, and the sealing and stability of optical cables are key. At present, the common method of watertight pressure resistance of optical cables is to use waterproof materials between the transparent material cladding of the optical fiber and the outer sheath of the optical cable, but the filling waterproof materials on the market are generally unable to withstand the high-pressure environment of the deep sea, which squeezes and destroys the waterproof materials, causing the seabed observation equipment connected to the underwater optical cable to be immersed in water and damaged. In some special application scenarios, such as equipment used on the seabed, it is necessary to use optical cables to connect underwater cameras to view the underwater deployment status of the seabed equipment in real time. After the seabed equipment is deployed, the optical cable cannot be recovered and needs to be cut by underwater robots or other submersibles, which will cause seawater to flow into the gap between the optical fiber and the protective layer of the abandoned optical cable. If the distance of seawater flowing into the optical cable is too long, it will damage the seabed instruments and equipment, causing serious economic losses. Summary of the invention

[0003] In view of the defects and shortcomings of the above-mentioned background technology, the present invention proposes a disposable cross-section watertight optical fiber for ocean detection and a preparation method thereof, and the technical solution thereof is as follows:

[0004] A disposable cross-section watertight optical fiber for ocean detection comprises an optical fiber core, a filling rope insulation tape, a double-sided plastic-coated steel tape and a polyethylene cable outer sheath. The outer layer of the optical fiber core is provided with the filling rope insulation tape, the double-sided plastic-coated steel tape and the polyethylene cable outer sheath in sequence, and the surface of the optical fiber core is coated with a transparent material cladding with a low refractive index; composite modified vulcanized polyurethane grouting is filled between the optical fiber core and the filling rope insulation tape.

[0005] Preferably, the composite modified vulcanized polyurethane grouting is nano-SiO 2 Modified vulcanized polyurethane grouting material.

[0006] Preferably, the outer sheath of the polyethylene cable is provided with a super-amphiphobic coating material having a thickness of 5-10 mm.

[0007] Preferably, the filling thickness of the composite modified vulcanized polyurethane grouting is 12-17 mm.

[0008] A method for preparing a disposable broken-section watertight optical fiber for ocean detection comprises the following steps: S1. Use coating to coat a layer of transparent material with low refractive index on the surface of the optical fiber; insert the coated optical fiber core into the polyethylene cable outer sheath covered with filling rope insulation tape and double-sided plastic-coated steel tape; S2. Fill the space between the optical fiber core and the filling rope insulation tape with composite modified vulcanized polyurethane grouting.

[0009] Preferably, the outer sheath of the polyethylene cable is coated with a super amphiphobic coating, and the preparation method is as follows: dispersing silicon dioxide in a mixed solution containing ethanol and ammonia water; The suspension is ultrasonically treated, and then perfluorosilane and ethyl orthosilicate are rapidly injected into the suspension under vigorous stirring at 800 r / min; the suspension is reacted at room temperature to form a coating layer on the surface of the silica, thereby forming a uniform silica amphiphobic suspension; Use a spray gun to spray the suspension on the surface of the polyethylene outer layer material in a nitrogen atmosphere, and place it vertically on a heating plate during the spraying process to obtain a super amphiphobic coating.

[0010] Preferably, the composite modified vulcanized polyurethane grouting preparation method is as follows: S21. Nano-SiO 2 After mixing with hydrophilic polyether polyol, ultrasonic vibration is used; S22 is dehydrated and dried, and cooled to room temperature, toluene diisocyanate is added and stirred; S23. The reaction mixture is placed in a water bath and heated, during which the temperature is controlled by condensing water, and the isocyanate value is ensured to be 4%-8%; S24. The diphenylmethane diisocyanate is added to the reaction body, and after the reaction is complete, dimethyl methylphosphonate is added, stirred and cooled to room temperature to obtain a prepolymer of a polyurethane grouting material; S25. triethanolamine as a catalyst and retarder was dissolved in deionized water with citric acid and stirred under a magnetic stirrer; S26. Adding diisopropylbenzene peroxide, methyltrichlorosilane and nano-silicon dioxide organic solvent dispersion to the mixture, and rapidly stirring under vacuum to obtain a prepolymer of a modified vulcanized polyurethane grouting material; S27. Continue stirring at a uniform speed at room temperature, and add a catalyst and a retarder to the prepolymer prepared above to obtain a modified polyurethane grouting material.

[0011] Compared with the prior art, the present invention has the following beneficial effects: The optical cable of the composite modified vulcanized polyurethane grouting filling material proposed in the present invention has a rigorous and simple preparation method, is economical and efficient, and has excellent mechanical properties, environmental protection characteristics, and good watertightness and pressure resistance. Combined with the polyethylene optical cable outer sheath made of polyvinyl chloride outer layer material and super-amphiphobic coating material, and adding filling rope insulation tape inside the optical cable, double-sided plastic-coated steel tape, the bending resistance and watertightness of the optical cable are enhanced, and the optical signal communication transmission performance of the optical fiber with damaged cross section is guaranteed, so that the cut optical cable can still be used as a sensing carrier for temperature rise, vibration and strain underwater. After the 30Mpa high-pressure hydrostatic pressure sealing tank test, the continuous pressure holding time is 2h, and the water immersion depth of the broken section of the optical cable is less than 20mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a cross-sectional diagram of a watertight optical fiber; Figure 2 It is a process flow chart for preparing composite modified vulcanized polyurethane grouting filling watertight pressure-resistant material; Figure 3 It is a process flow chart for preparing super-amphiphobic coating materials; Figure 4 This is a schematic diagram of the application of disposable watertight optical fiber cable; 1. Optical fiber core; 2. Transparent material cladding; 3. Composite modified vulcanized polyurethane grouting layer; 4. Filling rope insulation tape; 5. Double-sided plastic-coated steel tape; 6. Polyethylene cable outer sheath. DETAILED DESCRIPTION

[0013] In order to facilitate the understanding of the present invention, the present invention is described in more detail below in conjunction with the accompanying drawings and specific embodiments. Preferred embodiments of the present invention are provided in the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0014] Figure 1 This is a cross-sectional view of a watertight optical cable. A disposable cross-sectional watertight optical fiber for ocean detection includes an optical fiber core, a filling rope insulation tape, a double-sided plastic-coated steel tape and a polyethylene cable outer sheath. The outer layer of the optical fiber core is provided with a filling rope insulation tape, a double-sided plastic-coated steel tape and a polyethylene cable outer sheath in sequence. The surface of the optical fiber core is coated with a low-refractive index transparent material cladding; the space between the optical fiber core and the filling rope insulation tape is filled with a composite modified vulcanized polyurethane grouting. The composite modified vulcanized polyurethane grouting is nano-SiO 2 Modified vulcanized polyurethane grouting material. The polyethylene cable outer sheath is provided with a super-amphiphobic coating material with a thickness of 5-10 mm. The filling thickness of the composite modified vulcanized polyurethane grouting is 12-17 mm.

[0015] Figure 2As shown, a method for preparing a disposable broken-section watertight optical fiber for ocean detection comprises the following steps:

[0016] The preparation of optical fiber core selects high-purity silica as the main material of the optical fiber core. After the material is melted, it is made into an optical fiber blank by drawing a preform rod. The optical fiber blank is placed in a high-temperature furnace, heated at a controlled temperature, and the optical fiber core is drawn using an optical fiber drawing machine or chemical vapor deposition technology. During the drawing process, the optical fiber blank is gradually drawn into a filament to form the structure of the optical fiber core.

[0017] The optical fiber filaments are coated for protection. A layer of transparent material is coated on the surface of the optical fiber by coating. The coating material is a low refractive index material. The coated optical fiber core is inserted into the polyethylene cable outer sheath with a filling rope insulation tape and a double-sided plastic-coated steel tape.

[0018] Furthermore, the polyethylene cable outer sheath is made of a polyvinyl chloride outer layer material and a super amphiphobic coating material.

[0019] The super-amphiphobic coating material is an impact-resistant super-amphiphobic coating prepared by the hydrolysis-condensation reaction of silicon dioxide nanoparticles and organic silane.

[0020] Taking the preparation of 100mL super-amphiphobic coating material as an example, the preparation process is as follows: Figure 3 shown.

[0021] Disperse 25 mg of silicon dioxide in a mixed solution containing ethanol and ammonia water; The suspension was sonicated for 30 min, and then 120 μL of perfluorosilane and 30 μL of ethyl orthosilicate were rapidly injected into the suspension under vigorous stirring at 800 r / min; After reacting for 2 h at room temperature, a coating layer is formed on the surface of silica, forming a uniform silica amphiphobic suspension; Use a spray gun to spray the suspension on the surface of the polyethylene outer layer material in a nitrogen atmosphere of 200 kPa. Place it vertically on a heating plate (30°C) during the spraying process to obtain an excellent super-amphiphobic coating.

[0022] The composite modified vulcanized polyurethane grouting material is injected between the outer protective layer and the coated optical fiber core. The nano-SiO2 modified vulcanized polyurethane grouting material is prepared by in-situ prepolymerization and dissolution kneading method by adding nano-SiO2. Figure 4 shown.

[0023] After mixing 6% nano-SiO2 with hydrophilic polyether polyol, ultrasonic vibration was used for 2 hours to ensure uniform mixing; Then dehydrate and dry, and wait for cooling to room temperature. Next, add toluene diisocyanate (TDI) and stir for 30 minutes to ensure uniform mixing; The reaction mixture was placed in a water bath at 60°C and heated for 4 hours. During this process, the temperature was controlled by condensing water and the isocyanate group (NCO) value was ensured to be 6%. Subsequently, 5 mg of diphenylmethane diisocyanate (MDI) was added to the reaction body, and the reaction was continued for 2.5 hours; After the reaction is completed, 10% by mass of dimethyl methylphosphonate (DMMP) is added, stirred for 30 minutes, and cooled to room temperature to obtain a prepolymer of the polyurethane grouting material.

[0024] Dissolve triethanolamine (TEOA) as a catalyst and retarder with citric acid in deionized water. Stir for 1 hour under a magnetic stirrer to ensure uniform mixing; Furthermore, dicumyl peroxide, methyltrichlorosilane and nano-silicon dioxide organic solvent dispersion are added to the mixed solution, and the mixture is rapidly stirred for 30 seconds under a vacuum environment to obtain a prepolymer of a modified vulcanized polyurethane grouting material.

[0025] Then, the mixture was stirred at a constant speed at room temperature, and 1% by mass of a catalyst and a retarder were added to the prepolymer prepared above, and stirred with a glass rod for 30 seconds to obtain a modified polyurethane grouting material.

[0026] Then, the filling layer of the watertight optical fiber cable is injected under pressure and cooled for 30 minutes at room temperature to complete the filling of the watertight and pressure-resistant material inside the optical cable.

[0027] After the preparation process of the above embodiment, a total of 5 watertight optical cables with a length of 1 m were potted, the optical cables were placed in a pressure tank, and hydrostatic pressure tests were carried out in 5 groups. The test data are shown in Table 1 below.

[0028] Table 1 is the hydrostatic pressure test data

[0029] The watertight pressure test results in the above table show that, for example, in the fifth test, under the condition of a pressure of 30Mpa, the prepared optical cable was kept under pressure in a hydrostatic pressure tank for 3 hours. After the optical cable was taken out, the water depth of the filling rope insulation tape inside was checked. The results showed that the water depths of the two ends of the optical cable were 20mm and 18mm respectively, and the polyethylene cable outer sheath of the 1m optical cable had no cracks or damage. This test result shows that the watertight optical fiber prepared in this embodiment can effectively prevent the external seawater from penetrating into deep-sea equipment and instruments through the inner layer of the broken cross section of the optical cable under deep-sea high-pressure conditions.

[0030] Figure 4It is a schematic diagram describing an application scenario in which an underwater optical fiber cable connecting a ship-borne or shore-based control unit and underwater oceanographic detection equipment is cut by a mobile submersible such as an underwater robot.

[0031] The method for preparing watertight and pressure-resistant materials for optical cables of this embodiment can also be widely used in the research of underwater optical fiber communication and sensing systems of general marine instruments and equipment, providing real-time and stable communication media and sensing carriers for related research work.

[0032] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A disposable cross-section watertight optical fiber for ocean detection, characterized in that: It includes an optical fiber core, a filling rope insulating tape, a double-sided plastic-coated steel tape and a polyethylene cable outer sheath. The outer layer of the optical fiber core is provided with a filling rope insulating tape, a double-sided plastic-coated steel tape and a polyethylene cable outer sheath in sequence. The surface of the optical fiber core is coated with a low-refractive index transparent material cladding; the space between the optical fiber core and the filling rope insulating tape is filled with composite modified vulcanized polyurethane grouting.

2. The disposable cross-section watertight optical fiber for ocean detection according to claim 1, characterized in that: The composite modified vulcanized polyurethane grouting material is nano-SiO2 modified vulcanized polyurethane grouting material.

3. The disposable cross-section watertight optical fiber for ocean detection according to claim 1, characterized in that: The outer sheath of the polyethylene cable is provided with a super-amphiphobic coating material with a thickness of 5-10 mm.

4. The disposable cross-section watertight optical fiber for ocean detection according to claim 1, characterized in that: The filling thickness of the composite modified vulcanized polyurethane grouting is 12-17 mm.

5. A method for preparing a disposable cross-section watertight optical fiber for ocean detection, characterized in that: The following steps are involved: S1. Use coating to coat a layer of transparent material with low refractive index on the surface of the optical fiber; insert the coated optical fiber core into the polyethylene cable outer sheath covered with filling rope insulation tape and double-sided plastic-coated steel tape; S2. Fill the space between the optical fiber core and the filling rope insulation tape with composite modified vulcanized polyurethane grouting.

6. The method for preparing a disposable watertight optical fiber for ocean detection according to claim 5, characterized in that: The outer sheath of the polyethylene cable is coated with a super-amphiphobic coating, and the preparation method is as follows: dispersing silicon dioxide in a mixed solution containing ethanol and ammonia water; The suspension was ultrasonically treated, and then perfluorosilane and ethyl orthosilicate were rapidly injected into the suspension under vigorous stirring at 800 r / min; The reaction takes place at room temperature to form a coating layer on the surface of the silica, forming a uniform silica amphiphobic suspension; Use a spray gun to spray the suspension on the surface of the polyethylene outer layer material in a nitrogen atmosphere, and place it vertically on a heating plate during the spraying process to obtain a super amphiphobic coating.

7. The method for preparing a disposable watertight optical fiber with a broken cross section for ocean detection according to claim 5, characterized in that: The preparation method of composite modified vulcanized polyurethane grouting is as follows: S21. After mixing the nano-SiO2 with the hydrophilic polyether polyol, ultrasonic vibration is used; S22 is dehydrated and dried, and cooled to room temperature, toluene diisocyanate is added and stirred; S23. The reaction mixture is placed in a water bath and heated, during which the temperature is controlled by condensing water, and the isocyanate value is ensured to be 4%-8%; S24. The diphenylmethane diisocyanate is added to the reaction body, and after the reaction is complete, dimethyl methylphosphonate is added, stirred and cooled to room temperature to obtain a prepolymer of a polyurethane grouting material; S25. triethanolamine as a catalyst and retarder was dissolved in deionized water with citric acid and stirred under a magnetic stirrer; S26. Adding diisopropylbenzene peroxide, methyltrichlorosilane and nano-silicon dioxide organic solvent dispersion to the mixture, and rapidly stirring under vacuum to obtain a prepolymer of a modified vulcanized polyurethane grouting material; S27. Continue stirring at a uniform speed at room temperature, and add a catalyst and a retarder to the prepolymer prepared above to obtain a modified polyurethane grouting material.

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