A rodent-proof optical cable with a rodent-proof coating and its manufacturing process

Abstract

This invention relates to the field of optical cable manufacturing technology, specifically to a rodent-proof optical cable with a rodent-proof coating structure and its manufacturing process. The process includes the following steps: preparing a temperature-sensitive outer shell material, preparing a cross-linked copolymer, preparing a temperature-sensitive capsaicin-releasing filler, and preparing a rodent-proof optical cable with a rodent-proof coating structure. This invention combines N-isopropylacrylamide with hydrogenated castor oil to construct a temperature-sensitive microsphere shell. In this combination, N-isopropylacrylamide, as the temperature-sensitive component, provides the basic temperature response characteristics of the system; hydrogenated castor oil, as a multifunctional cross-linking agent and reinforcing phase, synergistically forms hydrophobic microdomains with the collapsed N-isopropylacrylamide chains at temperatures above the minimum critical dissolution temperature, significantly releasing capsaicin. At low temperatures, the network absorbs water and swells, blocking capsaicin release and preventing further release, thus enabling the microspheres to achieve effective temperature-controlled release.

Description

Technical Field

[0001] This invention relates to the field of optical cable manufacturing technology, specifically to a rodent-proof optical cable with a rodent-proof coating structure and its manufacturing process. Background Technology

[0002] Optical cables are frequently threatened by rodents in power and telecommunications installations, leading to line damage, signal interruptions, and significant economic losses. Traditional rodent control measures are mainly divided into physical and chemical protection. Physical protection, such as using rigid plastic or metal armor layers, is effective to some extent, but suffers from drawbacks such as heavy weight, poor flexibility, and high cost. Chemical protection often involves adding irritating chemical repellents such as capsaicin to the cable sheath.

[0003] However, capsaicin, a small molecule, is easily volatilized and decomposed in the high-temperature environment of polymer processing, and it will naturally migrate and volatilize during long-term use, resulting in a rapid decline in rodent-repelling efficacy. Secondly, the blending method of directly adding capsaicin lacks release control, cannot provide a high concentration of rapid stimulation at the moment of rodent biting, has low utilization rate, mediocre rodent-repelling effect, and may cause waste due to continuous release.

[0004] To overcome the above shortcomings, microencapsulation technology has been introduced to improve the stability of capsaicin. However, conventional microcapsule wall materials are mostly static structures, and their release mechanism depends on the physical destruction of the wall material or a slow diffusion process. They cannot make targeted intelligent responses, which often results in the release of capsaicin not being concentrated in the period when mice are most active, thus leading to the waste of capsaicin and other insecticidal ingredients.

[0005] Therefore, the present invention provides a rodent-proof optical cable with a rodent-proof coating structure and a manufacturing process thereof, thereby solving the problems existing in the prior art. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a rodent-proof optical cable with a rodent-proof coating structure and its manufacturing process.

[0007] A rodent-proof optical cable with a rodent-proof coating structure includes the following structure:

[0008] From the inside out, it consists of a cable core, a sheath layer, a rodent-proof coating, and an outer protective layer;

[0009] The cable core is made of optical fiber;

[0010] The sheath layer is made of polyethylene, and the surface of the sheath layer is coated with a rodent-proof coating. The outer side is covered with a protective layer composed of polyethylene.

[0011] A manufacturing process for a rodent-proof optical cable with a rodent-proof coating structure specifically includes the following steps:

[0012] S1: Preparation of temperature-sensitive shell material

[0013] Hydrogenated castor oil was mixed with acryloyl chloride, and then pyridine was added as a catalyst for the reaction. The product was precipitated with ice-cold ether, centrifuged, and then vacuum dried to obtain acrylic hydrogenated castor oil. N-isopropylacrylamide was mixed with acrylic hydrogenated castor oil and dissolved in an ethanol aqueous solution. Azobisisobutyronitrile was then added, and the mixture was heated and stirred for the reaction. A crosslinking agent was then added for the reaction. The product was poured into ice-cold ether to precipitate, and the solid material was collected by centrifugation and vacuum dried to constant weight to obtain a temperature-sensitive shell material.

[0014] S2: Preparation of crosslinked copolymers

[0015] Gelatin was dissolved in deionized water to obtain a gelatin solution. Palmitic acid and N-hydroxysuccinimide were dissolved in anhydrous DMSO, and EDC was added. The mixture was stirred at room temperature to obtain an activated palmitic acid solution. The activated palmitic acid solution was added dropwise to the gelatin solution while stirring. The product was dialyzed to remove unreacted palmitic acid, and then freeze-dried to obtain a gelatin-palmitic acid complex. The gelatin-palmitic acid complex was dissolved in deionized water, and an equal volume of ethanol was added dropwise. The mixture was sonicated, and genipin was added to react and obtain a crosslinked copolymer.

[0016] S3: Preparation of temperature-sensitive capsaicin release filler

[0017] Capsaicin was mixed with cross-linked copolymer and dissolved in dichloromethane. The mixture was ultrasonically emulsified, and Span 80 was added to obtain an oil phase. The temperature-sensitive shell material was dispersed in water to obtain an aqueous phase. The aqueous phase was added dropwise to the oil phase at a volume ratio of 1:(4-6). The mixture was homogenized for 3-5 minutes to form a double emulsion. Calcium chloride solution was then added and stirred. Dichloromethane was removed by vacuum distillation. The mixture was centrifuged and dried, and the microspheres were collected to obtain the temperature-sensitive capsaicin release filler.

[0018] S4: Prepare a rodent-proof optical cable with a rodent-proof coating structure.

[0019] Epoxy resin and thermosensitive capsaicin filler were weighed and added to a planetary mixer. Wetting and dispersing agent and defoamer were added and stirred to obtain a slurry. The slurry was allowed to stand, and a curing agent was added dropwise. After the addition was complete, the mixture was continued, and the mixture was degassed under vacuum and filtered to obtain a rodent-proof coating liquid. Polyethylene was extruded through an extruder and coated with the rodent-proof coating liquid at the same time to obtain a sheath layer of optical cable composed of polyethylene and a rodent-proof coating on the surface of the sheath layer. Then, a polyethylene sheath was wrapped on the outside to obtain a protective layer, and finally a rodent-proof optical cable with a rodent-proof coating structure was obtained.

[0020] Furthermore, step S1 specifically includes the following steps:

[0021] Hydrogenated castor oil and acryloyl chloride were mixed in a molar ratio of 1:(2-3), and 5-7% of pyridine (by total mass of hydrogenated castor oil and acryloyl chloride) was added as a catalyst. The mixture was reacted in an oil bath at 60-70°C for 6-7 hours. The product was precipitated with ice-cold ether, centrifuged, and then vacuum dried to obtain acrylic hydrogenated castor oil.

[0022] N-Isopropylacrylamide and hydrogenated castor oil with acrylate were mixed at a mass ratio of (4-5):1 and dissolved in an ethanol aqueous solution with a concentration of 50-60wt%. The total concentration of N-isopropylacrylamide and hydrogenated castor oil with acrylate was adjusted to 20% w / v. Then, 0.5-0.7% of azobisisobutyronitrile (AIBN) was added to the above system. The temperature was increased to 70-72℃ at a rate of 2℃ / min and reacted for 4-5 hours under stirring at 300-400 r / min. The temperature was then reduced to 50-54℃, and 0.1-0.3% of a crosslinking agent was added to the total system. The reaction was carried out for 2-3 hours. The product was poured into ice-cold ether to precipitate. The solid material was collected by centrifugation and vacuum dried to constant weight to obtain the temperature-sensitive shell material.

[0023] Furthermore, step S2 specifically includes the following steps:

[0024] Dissolve gelatin in deionized water at 50-60℃ and adjust the concentration to 5-7% (w / v). Adjust the pH to 7.5 to obtain a gelatin solution.

[0025] Palmitic acid and N-hydroxysuccinimide were dissolved in anhydrous DMSO at a mass ratio of 1:(1-1.2), and 10-20% EDC (total mass of palmitic acid and N-hydroxysuccinimide) was added. The mixture was stirred at room temperature for 4-5 hours to obtain an activated palmitic acid solution.

[0026] The activated palmitic acid solution was added dropwise to the gelatin solution and stirred at a constant temperature of 45-55℃ for 12-13 hours. After stirring, the product was dialyzed for 72-74 hours to remove unreacted palmitic acid. After freeze-drying, the gelatin-palmitic acid complex was obtained.

[0027] The gelatin-palmitic acid complex was dissolved in deionized water at pH 6-6.4, and an equal volume of ethanol was added dropwise. The mixture was ultrasonically treated at 100W for 5-7 minutes to induce palmitic acid self-assembly and form core-shell micelles. 0.1% (w / v) genipin was added, and the mixture was reacted at 50-60℃ for 2-3 hours to obtain the cross-linked copolymer.

[0028] Furthermore, step S3 specifically includes the following steps:

[0029] Capsaicin and cross-linked copolymer were mixed at a mass ratio of 1:(5-7) and completely dissolved in dichloromethane, with the content controlled at 15% (w / v). The mixture was ultrasonically emulsified at 200W for 2-3 minutes, and then 2-4% of Span 80 by total mass was added to obtain the oil phase.

[0030] The temperature-sensitive shell material was dispersed in water at a concentration of 10% (w / v) to obtain an aqueous phase.

[0031] The aqueous phase is added dropwise to the oil phase at a volume ratio of 1:(4-6). The mixture is homogenized at 8000-9000 r / min for 3-5 min to form a double emulsion. Then, 4-6% of the total system mass of calcium chloride solution is added and stirred at room temperature for 1-2 hours. Dichloromethane is removed by vacuum distillation at 40-50℃. The mixture is then centrifuged and dried, and the microspheres are collected to obtain the thermosensitive capsaicin release filler.

[0032] Furthermore, step S4 specifically includes the following steps:

[0033] Weigh 100-110 parts by weight of epoxy resin and 10-20 parts by weight of thermosensitive capsaicin filler and add them to a planetary mixer. Add 0.5-0.7 parts by weight of wetting and dispersing agent and 0.2-0.4 parts by weight of defoamer. Stir for 20-30 minutes to obtain a slurry. Let the slurry stand in a water bath at 25-35℃ for 10-20 minutes. Add 3-5 parts by weight of curing agent dropwise while stirring at 200-300 r / min. After the addition is complete, continue mixing at this speed for 10-20 minutes. Degas under vacuum for 5-7 minutes. Filter with a 500-mesh metal filter to obtain a rodent-proof coating liquid.

[0034] Polyethylene is extruded through an extruder and simultaneously coated with a rodent-proof coating liquid to obtain a sheath layer of the optical cable composed of polyethylene and a rodent-proof coating coated on the surface of the sheath layer. Then, a polyethylene sheath is wrapped on the outside to obtain a protective layer, and finally a rodent-proof optical cable with a rodent-proof coating structure is obtained.

[0035] Furthermore, the crosslinking agent is 4ARM-PEG-SH.

[0036] Furthermore, the concentration of the calcium chloride solution is 0.1-0.12M.

[0037] Furthermore, the mass ratio of the activated palmitic acid solution to the gelatin solution is 1:(4-6).

[0038] Furthermore, the MWCO during dialysis is 8-14 kDa.

[0039] The present invention has the following advantages:

[0040] 1. This invention constructs a temperature-sensitive microsphere shell by combining N-isopropylacrylamide with hydrogenated castor oil. In this combination, N-isopropylacrylamide serves as the temperature-sensitive component, and its polymer chains undergo a reversible hydrophilic-hydrophobic transition near the minimum critical dissolution temperature, providing the system with basic temperature response characteristics. Hydrogenated castor oil serves as a multifunctional crosslinking agent and reinforcing phase. Its rigid hydrophobic long chains can not only significantly improve the mechanical strength and toughness of the polymer network through covalent crosslinking, but also, when the temperature is higher than the minimum critical dissolution temperature, synergistically form hydrophobic microdomains with the collapsed N-isopropylacrylamide chains, significantly releasing capsaicin. At low temperatures, the network absorbs water and swells to block capsaicin, preventing its release, thus enabling the microspheres to achieve effective temperature-controlled release.

[0041] 2. This invention covalently grafts hydrophobic palmitic acid chains onto a hydrophilic gelatin backbone to form an amphiphilic gelatin-palmitic acid complex. This complex allows for ultrasonic-induced self-assembly in an aqueous phase to form a stable micelle structure with a hydrophobic palmitic acid chain core and a hydrophilic gelatin shell. Genipin is then used to crosslink and solidify the gelatin shell layer, ultimately constructing a structurally stable core-shell nanoparticle. This system combines the good biocompatibility of gelatin with the hydrophobic drug-carrying capacity provided by palmitic acid chains. Furthermore, crosslinking enhances the stability of the micelles, achieving efficient and high-volume loading of capsaicin.

[0042] 3. This invention uses a temperature-sensitive outer shell material as the aqueous phase and a mixture of capsaicin and cross-linked copolymers as the oil phase to prepare a temperature-sensitive capsaicin-releasing filler, which is then added to an epoxy coating for protecting optical cables. By employing a unique triple protection and controlled-release mechanism of "core-shell structure - temperature-sensitive microspheres - epoxy coating," a high-performance rodent-repellent coating system integrating passive protection and active repellency is constructed. In the innermost layer of the system, gelatin-palmitic acid cross-linked core-shell micelles act as nanocontainers. Their hydrophobic core effectively encapsulates capsaicin molecules, while the hydrophilic cross-linked shell provides a diffusion barrier, significantly improving the stability of capsaicin during processing and storage, preventing its oxidation and volatilization. The middle layer, a temperature-sensitive polymer shell, maintains its hydrophilicity at room temperature. In a water-swelled state, capsaicin is tightly sealed. When a mouse gnaws on the optical cable, generating frictional heat that causes the local temperature to exceed the minimum critical dissolution temperature, the polymer chain undergoes a violent hydrophilic-hydrophobic transition, and the chain segments collapse rapidly, thereby efficiently releasing the encapsulated capsaicin. This mouse-bite-based triggering mechanism greatly improves the utilization efficiency and response speed of capsaicin. At the moment of biting, the mechanical rupture of microspheres caused by physical damage to the coating also works synergistically with the thermal triggering effect, achieving targeted, high-concentration release in the mouse's mouth, thus producing an immediate and strong repellent effect. The bitten area will then begin to release capsaicin, protecting the bitten area from secondary biting and thus achieving long-term protection of the optical cable. Attached Figure Description

[0043] Figure 1 This is a process flow diagram of the preparation process of the rodent-proof optical cable with a rodent-proof coating structure according to the present invention. Detailed Implementation

[0044] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this invention.

[0045] Example 1

[0046] A manufacturing process for a rodent-proof optical cable with a rodent-proof coating structure, such as... Figure 1 As shown, it includes the following steps:

[0047] S1: Preparation of temperature-sensitive shell material

[0048] Hydrogenated castor oil and acryloyl chloride were mixed in a molar ratio of 1:2. Then, pyridine (5% by mass of the total hydrogenated castor oil and acryloyl chloride) was added as a catalyst. The mixture was reacted in an oil bath at 60°C for 6 hours. The product was precipitated with ice-cold ether, centrifuged, and then vacuum dried to obtain acrylic hydrogenated castor oil.

[0049] N-Isopropylacrylamide and hydrogenated castor oil with acrylate were mixed at a mass ratio of 4:1 and dissolved in a 50wt% ethanol aqueous solution. The total concentration of N-isopropylacrylamide and hydrogenated castor oil with acrylate was adjusted to 20% w / v. Then, 0.5% of azobisisobutyronitrile (AIBN) was added to the above system. The mixture was heated to 70℃ at a rate of 2℃ / min and reacted for 4 hours with stirring at 300 r / min. The temperature was then lowered to 50℃, and 0.1% of the total system mass of crosslinking agent 4ARM-PEG-SH was added. The mixture was reacted for 2 hours, and the product was poured into ice-cold ether to precipitate. The solid material was collected by centrifugation and vacuum dried to constant weight to obtain the temperature-sensitive shell material.

[0050] S2: Preparation of crosslinked copolymers

[0051] Dissolve gelatin in deionized water at 50℃ and adjust the concentration to 5% (w / v). Adjust the pH to 7.5 to obtain a gelatin solution.

[0052] Palmitic acid and N-hydroxysuccinimide were dissolved in anhydrous DMSO at a mass ratio of 1:1. EDC of 10% of the total mass of palmitic acid and N-hydroxysuccinimide was added and stirred at room temperature for 4 hours to obtain an activated palmitic acid solution.

[0053] The activated palmitic acid solution was added dropwise to the gelatin solution at a mass ratio of 1:4. The mixture was stirred at 45°C for 12 hours. After stirring, the product was dialyzed for 72 hours to remove unreacted palmitic acid. The MWCO during dialyzed was 8 kDa. The gelatin-palmitic acid complex was obtained after freeze-drying.

[0054] The gelatin-palmitic acid complex was dissolved in deionized water at pH 6, and an equal volume of ethanol was added dropwise. The mixture was sonicated at 100W for 5 minutes to induce palmitic acid self-assembly and form core-shell micelles. 0.1% (w / v) genipin was added, and the mixture was reacted at 50°C for 2 hours to obtain a cross-linked copolymer.

[0055] S3: Preparation of temperature-sensitive capsaicin release filler

[0056] Capsaicin and cross-linked copolymer were mixed at a mass ratio of 1:5 and completely dissolved in dichloromethane, with the content controlled at 15% (w / v). The mixture was ultrasonically emulsified at 200W for 2 minutes, and then 2% of Span 80 by total mass was added to obtain the oil phase.

[0057] The temperature-sensitive shell material was dispersed in water at a concentration of 10% (w / v) to obtain an aqueous phase.

[0058] The aqueous phase was added dropwise to the oil phase at a volume ratio of 1:4. The mixture was homogenized at 8000 r / min for 3 min to form a double emulsion. Then, 4% (by mass) of calcium chloride solution (0.1 M) was added and stirred at room temperature for 1 hour. Dichloromethane was removed by vacuum distillation at 40 °C. The mixture was then centrifuged and dried, and the microspheres were collected to obtain the thermosensitive capsaicin release filler.

[0059] S4: Prepare a rodent-proof optical cable with a rodent-proof coating structure.

[0060] Weigh 100 parts by weight of epoxy resin and 10 parts by weight of thermosensitive capsaicin filler and add them to a planetary mixer. Add 0.5 parts by weight of wetting and dispersing agent BYK-3455 and 0.2 parts by weight of defoamer BYK-055. Stir for 20 minutes to obtain a slurry. Let the slurry stand in a 25°C water bath for 10 minutes. Add 3 parts by weight of curing agent Ancamide®260A dropwise while stirring at 200 r / min. After the addition is complete, continue mixing at this speed for 10 minutes. Vacuum degas for 5 minutes and filter through a 500-mesh metal filter to obtain a rodent-proof coating liquid.

[0061] Polyethylene is extruded through an extruder and simultaneously coated with a rodent-proof coating liquid to obtain a sheath layer of the optical cable composed of polyethylene and a rodent-proof coating coated on the surface of the sheath layer. Then, a polyethylene sheath is wrapped on the outside to obtain a protective layer, and finally a rodent-proof optical cable with a rodent-proof coating structure is obtained.

[0062] Example 2

[0063] A manufacturing process for a rodent-proof optical cable with a rodent-proof coating structure, such as... Figure 1 As shown, it includes the following steps:

[0064] S1: Preparation of temperature-sensitive shell material

[0065] Hydrogenated castor oil and acryloyl chloride were mixed at a molar ratio of 1:2.5, and then pyridine (6% by mass of the total hydrogenated castor oil and acryloyl chloride) was added as a catalyst. The mixture was reacted in an oil bath at 65°C for 6.5 hours. The product was precipitated with ice-cold diethyl ether, centrifuged, and then vacuum dried to obtain acrylic hydrogenated castor oil.

[0066] N-Isopropylacrylamide and hydrogenated castor oil with acrylate were mixed at a mass ratio of 4.5:1 and dissolved in a 55wt% ethanol aqueous solution. The total concentration of N-isopropylacrylamide and hydrogenated castor oil with acrylate was adjusted to 20% w / v. Then, 0.6% of the above system mass of azobisisobutyronitrile was added, and the mixture was heated to 71℃ at a rate of 2℃ / min and reacted for 4.5h with stirring at 350℃ / min. The mixture was then cooled to 52℃, and 0.2% of the total system mass of crosslinking agent 4ARM-PEG-SH was added. The mixture was reacted for 2.5h, and the product was poured into ice-cold diethyl ether to precipitate. The solid material was collected by centrifugation and vacuum dried to constant weight to obtain the temperature-sensitive shell material.

[0067] S2: Preparation of crosslinked copolymers

[0068] Gelatin was dissolved in deionized water at 55℃ and the concentration was adjusted to 6% (w / v). The pH was then adjusted to 7.5 to obtain a gelatin solution.

[0069] Palmitic acid and N-hydroxysuccinimide were dissolved in anhydrous DMSO at a mass ratio of 1:1.1. EDC of 15% of the total mass of palmitic acid and N-hydroxysuccinimide was added and stirred at room temperature for 4.5 h to obtain an activated palmitic acid solution.

[0070] The activated palmitic acid solution was added dropwise to the gelatin solution at a mass ratio of 1:5. The mixture was stirred at 50°C for 12.5 hours. After stirring, the product was dialyzed for 73 hours to remove unreacted palmitic acid. The MWCO during dialyzed solution was 10 kDa. The gelatin-palmitic acid complex was obtained after freeze-drying.

[0071] The gelatin-palmitic acid complex was dissolved in deionized water at pH 6.2, and an equal volume of ethanol was added dropwise. The mixture was then sonicated at 100W for 6 minutes to induce palmitic acid self-assembly, forming core-shell micelles. 0.1% (w / v) genipin was added, and the mixture was reacted at 55°C for 2.5 hours to obtain the cross-linked copolymer.

[0072] S3: Preparation of temperature-sensitive capsaicin release filler

[0073] Capsaicin and cross-linked copolymer were mixed at a mass ratio of 1:6 and completely dissolved in dichloromethane, with the content controlled at 15% (w / v). The mixture was ultrasonically emulsified at 200W for 2.5 min, and then 3% of Span 80 by mass was added to obtain the oil phase.

[0074] The temperature-sensitive shell material was dispersed in water at a concentration of 10% (w / v) to obtain an aqueous phase.

[0075] The aqueous phase was added dropwise to the oil phase at a volume ratio of 1:5. The mixture was homogenized at 8500 r / min for 4 min to form a double emulsion. Then, a calcium chloride solution (0.11 M) at 5% of the total system mass was added and stirred at room temperature for 1.5 hours. Dichloromethane was removed by vacuum distillation at 45 °C. The mixture was then centrifuged and dried, and the microspheres were collected to obtain the thermosensitive capsaicin release filler.

[0076] S4: Prepare a rodent-proof optical cable with a rodent-proof coating structure.

[0077] Weigh 105 parts by weight of epoxy resin and 15 parts by weight of thermosensitive capsaicin filler and add them to a planetary mixer. Add 0.6 parts by weight of wetting and dispersing agent BYK-3455 and 0.3 parts by weight of defoamer BYK-055. Stir for 25 minutes to obtain a slurry. Let the slurry stand in a 30°C water bath for 15 minutes. Add 4 parts by weight of curing agent Ancamide®260A dropwise while stirring at 250 r / min. After the addition is complete, continue mixing at this speed for 15 minutes. Degas under vacuum for 6 minutes and filter through a 500-mesh metal filter to obtain a rodent-proof coating liquid.

[0078] Polyethylene is extruded through an extruder and simultaneously coated with a rodent-proof coating liquid to obtain a sheath layer of the optical cable composed of polyethylene and a rodent-proof coating coated on the surface of the sheath layer. Then, a polyethylene sheath is wrapped on the outside to obtain a protective layer, and finally a rodent-proof optical cable with a rodent-proof coating structure is obtained.

[0079] Example 3

[0080] A manufacturing process for a rodent-proof optical cable with a rodent-proof coating structure, such as... Figure 1 As shown, it includes the following steps:

[0081] S1: Preparation of temperature-sensitive shell material

[0082] Hydrogenated castor oil and acryloyl chloride were mixed in a molar ratio of 1:3. Then, pyridine (7% by mass of the total hydrogenated castor oil and acryloyl chloride) was added as a catalyst. The mixture was reacted in an oil bath at 70°C for 7 hours. The product was precipitated with ice-cold ether, centrifuged, and then vacuum dried to obtain acrylic hydrogenated castor oil.

[0083] N-Isopropylacrylamide and hydrogenated castor oil with acrylate were mixed at a mass ratio of 5:1 and dissolved in a 60wt% ethanol aqueous solution. The total concentration of N-isopropylacrylamide and hydrogenated castor oil with acrylate was adjusted to 20% w / v. Then, 0.7% of azobisisobutyronitrile (AIBN) was added to the above system. The mixture was heated to 72℃ at a rate of 2℃ / min and reacted for 5h with stirring at 400r / min. The temperature was then lowered to 54℃, and 0.3% of the total system mass of crosslinking agent 4ARM-PEG-SH was added. The mixture was reacted for 3h, and the product was poured into ice-cold ether to precipitate. The solid material was collected by centrifugation and vacuum dried to constant weight to obtain the temperature-sensitive shell material.

[0084] S2: Preparation of crosslinked copolymers

[0085] Gelatin was dissolved in deionized water at 60℃ and the concentration was adjusted to 7% (w / v). The pH was then adjusted to 7.5 to obtain a gelatin solution.

[0086] Palmitic acid and N-hydroxysuccinimide were dissolved in anhydrous DMSO at a mass ratio of 1:1.2. Then, 20% EDC (by mass of palmitic acid and N-hydroxysuccinimide) was added and the mixture was stirred at room temperature for 5 hours to obtain an activated palmitic acid solution.

[0087] The activated palmitic acid solution was added dropwise to the gelatin solution at a mass ratio of 1:6. The mixture was stirred at 55°C for 13 hours. After stirring, the product was dialyzed for 74 hours to remove unreacted palmitic acid. The MWCO during dialyzed solution was 14 kDa. The gelatin-palmitic acid complex was obtained after freeze drying.

[0088] The gelatin-palmitic acid complex was dissolved in deionized water at pH 6.4, and an equal volume of ethanol was added dropwise. The mixture was then sonicated at 100W for 7 minutes to induce palmitic acid self-assembly and form core-shell micelles. 0.1% (w / v) genipin was added, and the mixture was reacted at 60°C for 3 hours to obtain the cross-linked copolymer.

[0089] S3: Preparation of temperature-sensitive capsaicin release filler

[0090] Capsaicin and cross-linked copolymer were mixed at a mass ratio of 1:7 and completely dissolved in dichloromethane, with the content controlled at 15% (w / v). The mixture was ultrasonically emulsified at 200W for 3 minutes, and then 4% of Span 80 by total mass was added to obtain the oil phase.

[0091] The temperature-sensitive shell material was dispersed in water at a concentration of 10% (w / v) to obtain an aqueous phase.

[0092] The aqueous phase was added dropwise to the oil phase at a volume ratio of 1:6. The mixture was homogenized at 9000 r / min for 5 min to form a double emulsion. Then, a calcium chloride solution of 6% (by mass of the total system) was added and stirred at room temperature for 2 hours. The calcium chloride solution concentration was 0.12 M. The dichloromethane was removed by vacuum distillation at 50 °C. The mixture was then centrifuged and dried, and the microspheres were collected to obtain the thermosensitive capsaicin release filler.

[0093] S4: Prepare a rodent-proof optical cable with a rodent-proof coating structure.

[0094] Weigh 110 parts by weight of epoxy resin and 20 parts by weight of thermosensitive capsaicin filler and add them to a planetary mixer. Add 0.7 parts by weight of wetting and dispersing agent BYK-3455 and 0.4 parts by weight of defoamer BYK-055. Stir for 30 minutes to obtain a slurry. Let the slurry stand in a 35°C water bath for 20 minutes. Add 5 parts by weight of curing agent Ancamide®260A dropwise while stirring at 300 r / min. After the addition is complete, continue mixing at this speed for 20 minutes. Degas under vacuum for 7 minutes. Filter through a 500-mesh metal filter to obtain a rodent-proof coating liquid.

[0095] Polyethylene is extruded through an extruder and simultaneously coated with a rodent-proof coating liquid to obtain a sheath layer of the optical cable composed of polyethylene and a rodent-proof coating coated on the surface of the sheath layer. Then, a polyethylene sheath is wrapped on the outside to obtain a protective layer, and finally a rodent-proof optical cable with a rodent-proof coating structure is obtained.

[0096] Comparative Example 1:

[0097] Compared with Example 1, the difference of Comparative Example 1 is that in step S1, acrylated hydrogenated castor oil is not added. Instead, N-isopropylacrylamide is directly dissolved in a 50wt% aqueous ethanol solution, heated to 70°C at a rate of 2°C / min, and reacted for 4 hours under stirring at 300r / min. The temperature is then lowered to 50°C, the product is poured into ice-cold ether to precipitate, the solid material is collected by centrifugation, and vacuum dried to constant weight to obtain the temperature-sensitive shell material. The remaining steps are unchanged, and this is referred to as Comparative Example 1.

[0098] Comparative Example 2:

[0099] Compared with Example 1, Comparative Example 2 differs in that step S2 is omitted, and instead the crosslinked copolymer in step S3 is replaced with gelatin. Capsaicin and gelatin are mixed at a mass ratio of 1:5 and completely dissolved in dichloromethane, with the content controlled at 15% (w / v). The mixture is ultrasonically emulsified at 200W for 2 minutes, and then 2% of Span 80 by total mass is added to obtain the oil phase. The remaining steps remain unchanged, and this is referred to as Comparative Example 2.

[0100] Comparative Example 3:

[0101] Compared with Example 1, Comparative Example 3 differs in that step S2 is omitted, and instead, the crosslinked copolymer in step S3 is replaced with palmitic acid. Capsaicin and palmitic acid are mixed at a mass ratio of 1:5 and completely dissolved in dichloromethane, with the content controlled at 15% (w / v). The mixture is ultrasonically emulsified at 200W for 2 minutes, and then 2% of Span 80 by total mass is added to obtain the oil phase. The remaining steps remain unchanged, and this is referred to as Comparative Example 3.

[0102] Comparative Example 4:

[0103] Compared with Example 1, the difference of Comparative Example 4 is that in step S3, the temperature-sensitive shell material dispersed in water is replaced with a polyvinyl alcohol aqueous solution, while the other steps remain unchanged. This is referred to as Comparative Example 4.

[0104] Comparative Example 5:

[0105] Comparative Example 5 is a commercially available rodent-proof optical cable.

[0106] The rodent-proof optical cables with rodent-proof coating structures of Examples 1-3 and Comparative Examples 1, 4 and 5 were tested according to GB / T34016-2017 "General Rules for Rodent-proof and Ant-proof Wires and Cables" to evaluate their rodent-proof level. The test results are shown in Table 1.

[0107] The temperature-sensitive capsaicin release fillers of Examples 1-3 and Comparative Examples 1, 4 and 5 were sampled before and after 2 hours of release in buffer solutions at different temperatures (25°C and 37°C) to determine the drug concentration and calculate the capsaicin release rate.

[0108] The loading rates of capsaicin in temperature-sensitive capsaicin-releasing fillers of Test Examples 1-3 and Comparative Examples 2-3 are shown in Table 3.

[0109]

[0110]

[0111]

[0112] As shown in Table 1, GB / T34016-2017 classifies the rodent-proof properties of optical cables into FS-1 (lowest) to FS-4 (highest). Examples 1-3 all reach FS-2, while Comparative Examples 1, 4, and 5 only reach FS-1. This indicates that the present invention uses the temperature-sensitive microsphere shell as the aqueous phase and a mixture of capsaicin and cross-linked copolymer as the oil phase to prepare a temperature-sensitive capsaicin-releasing filler, which is then added to the epoxy coating to protect the optical cable. By employing a unique triple protection and controlled release mechanism of "core-shell structure - temperature-sensitive microspheres - epoxy coating", a high-performance rodent-proof coating integrating passive protection and active repellency functions is constructed. In this layered system, when rats gnaw on the optical cable, generating frictional heat that causes the local temperature to exceed the minimum critical melting temperature, the polymer chains undergo a dramatic hydrophilic-hydrophobic transition, and the chain segments rapidly collapse. This efficiently releases the encapsulated capsaicin. Furthermore, the mechanical rupture of the microspheres caused by the physical damage to the coating at the moment of biting also works synergistically with the thermal triggering effect, achieving targeted, high-concentration release within the rat's mouth. This results in an immediate and strong repellent effect. The bitten areas then begin to release capsaicin, protecting them from further biting and thus providing long-term protection for the optical cable and improving its rodent-proof level.

[0113] As can be seen from Table 2, Examples 1-3 showed low release rates at 25°C, while the release rate increased significantly at 37°C. Comparative Examples 4 and 5 showed little difference in release rates at 25°C and 37°C. Although Comparative Example 1 showed a change in release rate, the change was not as large as in the Examples. This is because the present invention combines N-isopropylacrylamide with hydrogenated castor oil to construct the temperature-sensitive microsphere shell. Hydrogenated castor oil, as a multifunctional crosslinking agent and reinforcing phase, not only significantly improves the mechanical strength and toughness of the polymer network through covalent crosslinking, but also releases capsaicin significantly when the temperature is above the minimum critical dissolution temperature by forming hydrophobic microdomains with the collapsed N-isopropylacrylamide chains. At low temperatures, the network absorbs water and swells to block capsaicin, preventing its release, thus enabling the microspheres to achieve effective temperature-controlled release. N-isopropylacrylamide, as the core component, lost its temperature-sensitive release ability when Comparative Example 4 completely abandoned the temperature-sensitive shell material.

[0114] As can be seen from Table 3, the capsaicin loading rate of the examples is above 87.6%, while the loading rates of Comparative Examples 2 and 3 are both less than 72%. This indicates that the gelatin-palmitic acid complex has both hydrophilic segments and a hydrophobic core, and has the highest encapsulation efficiency for the hydrophobic drug capsaicin. When used alone, the loading rate decreases significantly.

[0115] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims. Parts not described in detail in this specification are prior art known to those skilled in the art.

Claims

1. A process for preparing a rodent resistant optical cable having a rodent resistant coating structure, characterized by, Specifically comprising the following steps: S1: preparing a temperature-sensitive shell material Hydrogenated castor oil is mixed with acryloyl chloride, and pyridine is added as a catalyst for reaction. The product is precipitated with ice ethanol, centrifuged, and vacuum dried to obtain acrylated hydrogenated castor oil. N-isopropyl acrylamide is mixed with acrylated hydrogenated castor oil and dissolved in an ethanol aqueous solution. Azo diisobutyronitrile is added, and the mixture is stirred and reacted at elevated temperature. A crosslinking agent is added, and the product is precipitated in ice ethanol. The solid material is collected by centrifugation and vacuum dried to constant weight to obtain the temperature-sensitive shell material. S2: preparing a crosslinked copolymer Gelatin is dissolved in deionized water to obtain a gelatin solution. Palmitic acid and N-hydroxysuccinimide are dissolved in anhydrous DMSO, and EDC is added. The mixture is stirred at room temperature to obtain an activated palmitic acid solution. The activated palmitic acid solution is added dropwise to the gelatin solution, and the mixture is stirred. The product is dialyzed to remove unreacted palmitic acid. The gelatin-palmitic acid complex is obtained by freeze-drying. The gelatin-palmitic acid complex is dissolved in deionized water, and an equal volume of ethanol is added. The mixture is ultrasonically treated, and genipin is added for reaction to obtain the crosslinked copolymer. S3: preparing a temperature-sensitive capsaicin release filler Capsaicin and the crosslinked copolymer are mixed and dissolved in dichloromethane, and ultrasonic emulsification is performed. Spans 80 is added to obtain an oil phase. The temperature-sensitive shell material is dispersed in water to obtain an aqueous phase. The aqueous phase is added dropwise to the oil phase, and the volume ratio of the aqueous phase to the oil phase is 1: (4-6). Homogenization is performed for 3-5 min to form a multiple emulsion. A calcium chloride solution is added and stirred. Dichloromethane is removed by reduced pressure distillation. The mixture is centrifuged and dried to collect microspheres to obtain the temperature-sensitive capsaicin release filler. S4: preparing a rodent-proof optical cable with a rodent-proof coating structure Epoxy resin and the temperature-sensitive capsaicin release filler are weighed and added to a planetary mixer. Wetting and dispersing agents and defoaming agents are added, and the mixture is stirred to obtain a slurry. The slurry is allowed to stand, and a curing agent is added dropwise. After the addition is completed, the mixture is continuously mixed, vacuum degassed, and filtered to obtain a rodent-proof coating liquid. Polyethylene is extruded through an extruder while being coated with the rodent-proof coating liquid to obtain a polyethylene jacket layer of the optical cable and a rodent-proof coating layer coated on the surface of the jacket layer. A polyethylene jacket is further coated on the outside to obtain a protective layer. Finally, a rodent-proof optical cable with a rodent-proof coating structure is obtained. The rodent-proof optical cable comprises the following structure: From the inside to the outside, it is composed of a cable core, a jacket layer, a rodent-proof coating layer, and an outer protective layer. The cable core is an optical fiber. The jacket layer is polyethylene, and the rodent-proof coating layer is coated on the surface of the jacket layer. The outer side of the rodent-proof coating layer is coated with a protective layer composed of polyethylene.

2. The process for preparing a rodent-resistant optical cable having a rodent-resistant coating structure according to claim 1, wherein, Step S1 specifically comprises the following steps: Hydrogenated castor oil is mixed with acryloyl chloride at a molar ratio of 1: (2-3). Pyridine is added as a catalyst at 5-7% of the total mass of hydrogenated castor oil and acryloyl chloride. The mixture is reacted in a 60-70°C oil bath for 6-7 hours. The product is precipitated with ice ethanol, centrifuged, and vacuum dried to obtain acrylated hydrogenated castor oil. N-isopropyl acrylamide and acrylated hydrogenated castor oil are mixed in a mass ratio of (4-5):1, then dissolved in an ethanol aqueous solution with a concentration of 50-60 wt%, and the total concentration of N-isopropyl acrylamide and acrylated hydrogenated castor oil is adjusted to 20% w / v; 0.5-0.7% of azobisisobutyronitrile of the total mass of the above system is added, the temperature is raised to 70-72°C at a rate of 2°C / min, and the reaction is carried out at a stirring speed of 300-400 r / min for 4-5 h; the temperature is lowered to 50-54°C, 0.1-0.3% of a crosslinking agent of the total mass of the system is added, and the reaction is carried out for 2-3 h; the product is precipitated in ice ethanol, the solid material is collected by centrifugation, and vacuum drying is performed until the weight is constant, thereby obtaining a temperature-sensitive shell material.

3. The process for preparing a rodent-resistant optical cable having a rodent-resistant coating structure according to claim 2, wherein Step S2 specifically includes the following steps: gelatin is dissolved in deionized water at 50-60°C and the concentration is adjusted to 5-7% (w / v), and the pH is adjusted to 7.5, thereby obtaining a gelatin solution; palmitic acid and N-hydroxysuccinimide are dissolved in anhydrous DMSO in a mass ratio of 1:(1-1.2), and 10-20% of EDC of the total mass of palmitic acid and N-hydroxysuccinimide is added, and stirring is carried out at room temperature for 4-5 h, thereby obtaining an activated palmitic acid solution; the activated palmitic acid solution is added dropwise to the gelatin solution, and stirring is carried out at a constant temperature of 45-55°C for 12-13 h; after the stirring is completed, the product is dialyzed for 72-74 h to remove unreacted palmitic acid, and freeze-drying is carried out, thereby obtaining a gelatin-palmitic acid complex; the gelatin-palmitic acid complex is dissolved in deionized water with a pH of 6-6.4, and an equal volume of ethanol is added dropwise, and 100W ultrasonic treatment is carried out for 5-7 min to induce self-assembly of palmitic acid, thereby forming core-shell micelles, and 0.1% (w / v) of genipin is added, and reaction is carried out at 50-60°C for 2-3 h, thereby obtaining a crosslinked copolymer.

4. The process for preparing a rodent-resistant optical cable having a rodent-resistant coating structure according to claim 3, wherein, Step S3 specifically includes the following steps: capsaicin and the crosslinked copolymer are mixed in a mass ratio of 1:(5-7) and completely dissolved in dichloromethane, and the content is controlled to be 15% (w / v), and 200W ultrasonic emulsification is carried out for 2-3 min, and then 2-4% of the total mass of Span 80 is added, thereby obtaining an oil phase; the temperature-sensitive shell material is dispersed in water, and the concentration is controlled to be 10% (w / v), thereby obtaining an aqueous phase; the aqueous phase is added dropwise into the oil phase, and the volume ratio of the aqueous phase to the oil phase is 1:(4-6), and homogenization is carried out at a speed of 8000-9000 r / min for 3-5 min, thereby forming a multiple emulsion, and then 4-6% of a calcium chloride solution of the total mass of the system is added, and stirring is carried out at room temperature for 1-2 h, and dichloromethane is removed by distillation under reduced pressure at 40-50°C, and the microspheres are collected by centrifugal drying, thereby obtaining a temperature-sensitive capsaicin release filler.

5. The process for preparing a rodent-resistant optical cable having a rodent-resistant coating structure according to claim 4, wherein, Step S4 specifically includes the following steps: Take 100-110 parts by mass of epoxy resin and 10-20 parts by mass of temperature-sensitive release capsaicin filler into a planetary mixer, add 0.5-0.7 parts by mass of wetting dispersant and 0.2-0.4 parts by mass of defoaming agent, stir for 20-30 minutes, obtain slurry, place the slurry in a water bath at 25-35°C for 10-20 minutes, add 3-5 parts by mass of curing agent dropwise under stirring at 200-300 r / min, continue mixing at this speed for 10-20 minutes after dropwise addition is completed, vacuum degassing for 5-7 minutes, filter with a 500-mesh metal filter to obtain a rat-proof coating liquid; The polyethylene is extruded through an extruder and simultaneously coated with the rat-proof coating liquid to obtain a sheath layer of the optical cable composed of polyethylene and a rat-proof coating layer coated on the surface of the sheath layer, and a protective layer is further coated on the outside of the sheath to obtain a rat-proof optical cable with a rat-proof coating structure.

6. The process for preparing a rodent-resistant optical cable having a rodent-resistant coating structure according to claim 2, wherein, The crosslinking agent is 4ARM-PEG-SH.

7. The process for preparing a rodent-resistant optical cable having a rodent-resistant coating structure according to claim 4, wherein, The concentration of the calcium chloride solution is 0.1-0.12 M.

8. The process for preparing a rodent-resistant optical cable having a rodent-resistant coating structure according to claim 3, wherein, The mass ratio of the activated palmitic acid solution and the gelatin solution is 1: (4-6).

9. The process for preparing a rodent-resistant optical cable having a rodent-resistant coating structure according to claim 3, wherein, The MWCO during dialysis is 8-14 kDa.

10. A rat-proof optical cable produced by the preparation process of the rat-proof optical cable with a rat-proof coating structure according to any one of claims 1-9.

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