Thermoplastic optical cable protection material and preparation method thereof

Abstract

The invention provides a thermoplastic optical cable protection material and a preparation method thereof.The preparation method comprises the steps that a nano-toughening component is dispersed to obtain a nano-micelle solution, matrix resin is placed in the nano-micelle solution, and a wet-solid mixture is obtained; mixing the wet solid mixture with a functional filler, and mixing at the temperature of 120-140 DEG C to obtain a semi-crosslinked mixture; coating the outer surface of the optical cable material with the semi-crosslinking mixture, heating to 150-160 DEG C, applying an excitation source to the semi-crosslinking mixture for surface curing, and cooling to obtain the thermoplastic optical cable protection material. Therefore, the cutting resistance and wear resistance of the thermoplastic optical cable protection material are effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of optical cable materials, and in particular relates to a thermoplastic optical cable protective material and a preparation method thereof. Background Art

[0002] During the laying or use of optical cables, they may encounter mechanical stresses such as external pulling, impact, bending, and knocking. If the optical cable is squeezed or twisted by external forces, the refractive index and stress distribution of the optical fiber core will change, resulting in optical signal attenuation or noise increase. Without a tough outer sheath, the internal fiber core can easily break or be damaged by microcracks, causing signal attenuation or complete failure. The outside world is often accompanied by moisture, rain, seawater, acidic and alkaline environments, or ultraviolet exposure. Without a sufficiently waterproof, chemically resistant, and ultraviolet-resistant sheath, the performance and life of the optical cable will be greatly shortened.

[0003] The optical cable sheath and protective materials in the related technology include polyvinyl chloride, polyethylene, etc., which have the following disadvantages in an environment with more external friction. On the one hand, the Shore hardness of commonly used polyvinyl chloride and polyethylene at room temperature is not high. When facing sharp objects, it is easier to produce cuts and has poor cutting resistance; on the other hand, when subjected to external friction, the molecular chain is prone to micro-plastic deformation or local adhesion, causing the material to show obvious wear in a short time. This viscoelastic property also causes the surface of the sheath to continuously "erase" the surface molecules during repeated friction, resulting in poor wear resistance. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a thermoplastic optical cable protective material and a preparation method thereof, aiming to solve the problem of poor cutting resistance and wear resistance of the optical cable protective material.

[0005] To solve the above technical problems, the present invention is implemented as follows: a method for preparing a thermoplastic optical cable protective material is provided, the steps comprising: S1, dispersing the nano toughening component to obtain a nano micelle solution, and then placing a matrix resin in the nano micelle solution to obtain a wet-solid mixture; S2, mixing the wet solid mixture and the functional filler, and kneading at a temperature of 120 to 140° C. to obtain a semi-crosslinked mixture; S3, coating the semi-crosslinked mixture on the outer surface of the optical cable material, heating to 150-160° C., applying an excitation source to the semi-crosslinked mixture for surface curing, and cooling to obtain a thermoplastic optical cable protective material.

[0006] In some embodiments of the present invention, in step S1, the nano-toughening component includes at least one of a lactide-caprolactone copolymer oligomer, a polyetheretherketone oligomer, and a polyurethane elastomer, and the matrix resin includes at least one of a polyamide resin, a polycarbonate resin, and an acrylic resin.

[0007] In some embodiments of the present invention, the mass ratio of the nanomicelle solution to the matrix resin is 1:3-10.

[0008] In some embodiments of the present invention, step S1 comprises: S1.1, placing the nano toughening component in a polar solvent, performing ultrasonic dispersion, adding an initiator and an activation regulator at the same time, the ultrasonic frequency is between 20 and 40 kHz, the ultrasonic power is 300 to 500 W, and the ultrasonic time is 30 to 60 min to obtain a nano micelle solution; S1.2, adding the matrix resin to the nanomicelle solution in batches, stirring at a stirring speed of 100-300 rpm for 30 min to obtain a wet-solid mixture.

[0009] In some embodiments of the present invention, in step S1.1, the polar solvent includes at least one of dichloromethane, chloroform, and ethanol, the initiator includes at least one of 2,2-dimethoxy-2-phenylethanone, isopropyl-9H-carbazole-1-yl-alkyl ketone derivatives, and lauroyl peroxide, and the mass percentage of the initiator to the wet solid mixture is 0.1-5%, and the activation regulator includes at least one of triethylamine, dibutyltin dilaurate, and p-toluenesulfonic acid, and the mass percentage of the activation regulator to the wet solid mixture is 0.05-2%.

[0010] In some embodiments of the present invention, in step S2, the functional filler includes at least one of hard ceramic particles, carbon fibers, and glass fibers, the particle size of the hard ceramic particles is 1~10μm, the particle size of the carbon fibers is 2~5mm and / or 10~20μm, and the particle size of the glass fibers is 3~6mm and / or 20~30μm.

[0011] In some embodiments of the present invention, the mass ratio of the functional filler to the wet-solid mixture is 1-3:7-9.

[0012] In some embodiments of the present invention, step S2 includes: S2.1, placing the wet solid mixture in a twin-screw extruder, the screw speed of the twin-screw extruder is 30-60 rpm, and firstly performing the first stage of heating and stirring at 100-110°C for 5-10 minutes; S2.2, add the functional filler after the surface modification by the coupling agent, and carry out the second stage of heating and stirring at 120-140°C for 10-20 minutes; S2.3. Finally, the third stage of heating and stirring is performed at 140-150°C for 3-5 minutes to obtain a semi-crosslinked mixture.

[0013] In some embodiments of the present invention, step S3 includes: S3.1, preheating the optical cable material to 70-80°C, and then coating the semi-crosslinked mixture on the optical cable material; S3.2, heating the semi-crosslinked mixture to 150-160°C, and continuously extruding the semi-crosslinked mixture and the optical cable material at an extrusion speed of 3-8 m / min; S3.3, during the extrusion process, applying an excitation source to the outer surface of the semi-crosslinked mixture for surface curing, the curing time being 5 to 60 seconds, wherein the excitation source comprises an ultraviolet lamp with a power of 8 to 12 kW / m or an infrared lamp with a power of 1 to 4 kW / m; S3.4. Use air cooling or forced airflow to quickly reduce the outer surface temperature of the semi-crosslinked mixture to 80-100°C, and then place it in a coolant circulation system to reduce the overall temperature of the semi-crosslinked mixture and the optical cable material to below room temperature to obtain a thermoplastic optical cable protective material.

[0014] The present invention provides a thermoplastic optical cable protective material, which is made by the above-mentioned preparation method of a thermoplastic optical cable protective material, wherein the thermoplastic optical cable protective material comprises a matrix resin, a nano-toughening component and a functional filler; wherein: The matrix resin is used to provide mechanical support for the thermoplastic optical cable protective material; The nano toughening component is used to improve the impact absorption and toughness of the thermoplastic optical cable protective material; The functional filler is used for strengthening the mechanical and physical properties of the thermoplastic optical cable protective material.

[0015] Compared with the prior art, the preparation method of the thermoplastic optical cable protective material in the present invention has the following beneficial effects: The nano-toughening components are made into nano-micelle solutions. These evenly dispersed nano-toughening components can be filled into the micro-voids of the matrix resin, and inhibit crack initiation or prevent crack propagation under stress, thereby improving the overall toughness and absorption capacity of external forces, and thus enhancing the resistance to cutting and wear. The functional filler modified by the coupling agent is then added, which not only has high hardness, but also can be firmly combined with the matrix resin to form a reinforced fiber structure, significantly improving the material's ability to resist local sharp cutting and reducing material shedding during wear. The matrix resin itself has a certain impact resistance and plastic deformation ability, and can form a multiphase composite network with the toughening components and functional fillers, which is more difficult to destroy when subjected to cutting or friction.

[0016] Multi-stage temperature-controlled mixing allows the functional filler to be evenly distributed and quickly solidified on the surface, forming a fine and solid hard toughening phase or fiber reinforcement phase, reducing agglomeration or void defects. The tough shell is formed to resist scratches and wear, and the elastic toughness is retained inside to absorb local sharp loads or impacts, improving the overall cutting resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The figure is a schematic flow chart of a method for preparing a thermoplastic optical cable protective material in one embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] When laying optical cables in rail transit, subways, and tunnels, they may be pulled between walls and brackets that are not smooth enough by threading machines or manual traction, resulting in long-distance high friction; vibrations and airflow shocks generated by high-speed trains, as well as scratches from manual mechanical tools in tunnels, can cause impact or wear on optical cables. Factories or logistics centers often install optical cables for machine vision or data communications. During the frequent movement of robotic arms and transmission systems, optical cables are susceptible to bending, sliding, and collisions; if there are metal debris or sharp objects in the surrounding environment such as machine tools and cutting machines, it is very easy to cut the outer sheath of the optical cable. In particular, when deploying and repairing optical cables, it is necessary to repeatedly pay out and reel in the cable between the reel and the installation point. If the construction equipment has sharp edges or the ground is rough, significant friction will be generated.

[0020] To improve the cutting resistance and abrasion resistance of the optical cable protective material, please refer to Figure 1 The present invention provides a method for preparing a thermoplastic optical cable protective material, the steps comprising: S1. Dispersing the nano toughening component to obtain a nano micelle solution, and then placing the matrix resin in the nano micelle solution to obtain a wet-solid mixture.

[0021] In this step, the nano toughening component is treated with polar solvent and ultrasonic energy to form a nano micelle solution, which can make the toughening component evenly dispersed at the nanoscale. Mixing the nano micelle solution with the matrix resin can obtain a more uniform toughening network structure in the subsequent process, and improve the impact toughness and fatigue tolerance of the material. By introducing initiators and activation regulators into the nano micelle solution, the matrix resin can achieve the formation of reversible chemical bonds during subsequent molding and heat treatment; at the same time, because it has not been completely cross-linked at this time, it is only in a wet solid state, retaining sufficient fluidity and flexibility for subsequent processing. After the wet solid mixture is generated in this step, the viscosity is moderate and the dispersion is uniform. Subsequently, the final protective layer is partially or completely cured (surface hardening) at medium temperature (step S2) and higher temperature or excitation conditions (step S3), which is conducive to the gradient performance design of thermoplastic optical cable protective materials.

[0022] In step S1, the nano toughening component includes at least one of lactide-caprolactone copolymer oligomer, polyetheretherketone oligomer, and polyurethane elastomer, and the matrix resin includes at least one of polyamide resin, polycarbonate resin, and acrylic resin. The mass ratio of the nano micelle solution to the matrix resin is 1:3-10.

[0023] Lactide-caprolactone copolymer oligomers help to form a flexible phase and reduce brittle fracture. Polyetheretherketone oligomers can remain stable at high temperatures or in specific chemical environments, improving high temperature tolerance. Polyurethane elastomers give the material excellent impact buffering ability and resilience toughness. By choosing one or more of them, the balance between toughness and strength can be adjusted according to the actual needs of optical cable protection. Polyamide resin brings high wear resistance and good impact toughness, suitable for harsh laying scenarios. Polycarbonate resin provides high transparency and excellent impact strength, suitable for environments that require visualization or high impact resistance. Acrylic-based resins maintain thermoplastic properties and are conducive to recycling and reuse. The mass ratio of 1:3~10 allows the nano-toughening component to fully exert the toughening effect without over-diluting the matrix resin and causing the rheological properties to lose control; it also takes into account the preparation cost and material properties, which is conducive to large-scale industrial applications.

[0024] Step S1 comprises: S1.1. Place the nano-toughening component in a polar solvent for ultrasonic dispersion, and add an initiator and an activation regulator at the same time. The ultrasonic frequency is between 20 and 40 kHz, the ultrasonic power is 300 to 500 W, and the ultrasonic time is 30 to 60 minutes to obtain a nano-micelle solution.

[0025] In step S1.1, the polar solvent includes at least one of dichloromethane, chloroform, and ethanol, the initiator includes at least one of 2,2-dimethoxy-2-phenylethanone, isopropyl-9H-carbazole-1-yl-alkyl ketone derivatives, and lauroyl peroxide, and the mass percentage of the initiator in the wet solid mixture is 0.1-5%, and the activation regulator includes at least one of triethylamine, dibutyltin dilaurate, and p-toluenesulfonic acid, and the mass percentage of the activation regulator in the wet solid mixture is 0.05-2%.

[0026] Using ultrasonic waves at a frequency of 20 to 40 kHz for 30 to 60 minutes, the originally easily agglomerated nano-toughening components can be dispersed to near-nanoscale in polar solvents to form a stable nano-micelle solution, thus avoiding large-scale agglomeration during subsequent mixing. During the ultrasonic process, the initiator and activation regulator are evenly mixed into the nano-micelle system, and some free radicals or catalytic sites can form activation areas, providing chemical prerequisites for the next step of combining with the matrix resin, which is conducive to the realization of subsequent partial reversible cross-linking. Ultrasonic dispersion is also conducive to controlling the viscosity of the solution, so that the subsequent addition of the matrix resin (step S1.2) can smoothly enter the micelle network, and finally obtain a uniform wet-solid mixture.

[0027] S1.2. Add the matrix resin to the nanomicelle solution in batches and stir at a speed of 100-300 rpm for 30 min to obtain a wet-solid mixture.

[0028] Stirring at a medium-low speed of 100-300rpm for 30 minutes can fully infiltrate the matrix resin into the nano-micelle network without forming large sticky masses or local solidification instantly. The nano-micelle solution already carries a certain number of active groups (initiators, activation regulators), which initially combine or associate with the surface molecules of the matrix resin during the stirring process to enhance the interfacial bonding strength and dispersion uniformity. Although there is some initial reaction, it is still in a wet-solid state at this time, retaining fluidity and plasticity, laying a stable process foundation for subsequent mixing (at 120-140°C) or coating (heating to 150-160°C + excitation source curing) links.

[0029] S2. Mix the wet solid mixture and the functional filler, and knead them at a temperature of 120 to 140° C. to obtain a semi-crosslinked mixture.

[0030] In step S2, the functional filler includes at least one of hard ceramic particles, carbon fibers, and glass fibers, the particle size of the hard ceramic particles is 1-10 μm, the particle size of the carbon fibers is 2-5 mm and / or 10-20 μm, and the particle size of the glass fibers is 3-6 mm and / or 20-30 μm. The mass ratio of the functional filler to the wet-solid mixture is 1-3:7-9.

[0031] Step S2 includes: S2.1. Place the wet-solid mixture in a twin-screw extruder with a screw speed of 30-60 rpm. Perform the first stage of heating and stirring at 100-110°C for 5-10 minutes.

[0032] Maintaining the temperature at 100-110°C for 5-10 minutes can partially volatilize and discharge the residual polar solvent (such as dichloromethane, chloroform, ethanol, etc.) in the wet-solid mixture formed in step S1, thereby reducing the probability of foam or bubble generation during subsequent mixing. By slightly increasing the temperature to 100-110°C, the viscosity of the mixture gradually decreases but still maintains a certain fluidity, which is conducive to uniform stirring at a screw speed of 30-60rpm, and will not enter the cross-linking reaction too quickly and cause the system to lose plasticity. This temperature range also allows the nano-toughening component (lactide-caprolactone copolymer oligomer, polyetheretherketone oligomer or polyurethane elastomer) to begin a deeper mutual penetration with the matrix resin, but has not yet been cross-linked on a large scale, ensuring that there is sufficient space for the subsequent adsorption and dispersion of the functional filler.

[0033] S2.2. Add the functional filler that has been surface-modified by the coupling agent, and carry out the second stage of heating and stirring at 120-140°C for 10-20 minutes.

[0034] After the wet-solid mixture is initially homogenized in the first stage, add the functional filler (hard ceramic particles, carbon fiber or glass fiber) into the twin-screw extruder to avoid premature addition that may cause filler agglomeration or a surge in material viscosity; stir at 120-140°C for 10-20 minutes. At this time, the wet-solid mixture has stronger fluidity and can evenly coat the surface of the functional filler to improve its reinforcement effect.

[0035] After the functional filler is treated with a coupling agent (such as silane, phenolic or acrylic surface treatment), it will produce a good interface reaction or bonding with the matrix resin (especially the structure containing unsaturated groups, imide groups, or urea groups) under medium temperature conditions, making the interface between the filler and the resin more stable and enhancing the overall mechanical properties. At this time, partial cross-linking or bonding begins to appear inside the material (by the combined action of the initiator and activation regulator in step S1.1), but it still maintains a plastic form. In the medium-speed shear (30~60rpm) of the twin-screw extruder with a temperature range of 120~140℃, the fiber or particulate filler is fully dispersed to avoid agglomeration or local voids, thereby forming a preliminary skeleton reinforcement effect, providing impact resistance, cutting resistance or tensile strength improvement for the optical cable sheath.

[0036] S2.3. Finally, the third stage of heating and stirring is performed at 140-150°C for 3-5 minutes to obtain a semi-crosslinked mixture.

[0037] Raising the temperature to 140-150°C and maintaining it for 3-5 minutes can make the pre-initiator (such as 2,2-dimethoxy-2-phenyl acetone, isopropyl-9H-carbazole-1-yl-alkyl ketone derivatives or lauroyl peroxide) produce more free radicals, or make the metal catalyst activation regulator more fully participate in the reaction, promoting the matrix or nano-toughening component to form a stronger cross-linked network in the local area. However, the degree of cross-linking has not yet reached full curing, and it is only called semi-cross-linking, which is conducive to the extrusion coating or surface hardening operation of the subsequent process (S3).

[0038] After 3 to 5 minutes of short-term high-temperature stirring, the position of the functional filler in the matrix is ​​initially fixed. At the same time, due to the short time, the material as a whole will not fall into an irreversible high cross-linking stage and can still retain sufficient fluidity or thermoplasticity. This equilibrium state enables the material to be better formed in the subsequent extrusion or coating process, and the optimal hardness is achieved when the surface layer is finally cured. The final product, the semi-cross-linked mixture, not only has a dispersed structure of reinforced fibers or particles, but also contains a partially cross-linked nano-toughening network, which significantly improves the impact resistance and tensile strength of the optical cable protective layer in the service environment; at the same time, there are still reversible or inadequately reacted chemical bonds inside, which provide the chemical prerequisite for subsequent recycling or secondary thermoplastic treatment.

[0039] S3, coating the semi-crosslinked mixture on the outer surface of the optical cable material, heating it to 150-160°C, applying an excitation source to the semi-crosslinked mixture for surface curing, and cooling it to obtain a thermoplastic optical cable protective material.

[0040] Step S3 includes: S3.1. Preheat the optical cable material to 70~80℃, and then apply the semi-crosslinked mixture on the optical cable material.

[0041] Preheating the cable material to 70~80℃ can make its surface closer to the temperature of the semi-crosslinked mixture to be coated, avoiding warping, bubbles or uneven local curing due to large temperature difference after coating. After the cable surface is moderately heated, the viscosity difference is smaller, which is more conducive to the semi-crosslinked mixture flowing on the outer surface of the cable and penetrating into the tiny bumps and grooves, improving the adhesion of the protective layer. The preheating temperature of 70~80℃ will not over-activate the initiator or activation regulator, allowing the semi-crosslinked mixture to remain plastic during coating without local premature curing.

[0042] S3.2. Heat the semi-crosslinked mixture to 150-160°C, and extrude the semi-crosslinked mixture and optical cable material continuously at an extrusion speed of 3-8 m / min.

[0043] The semi-crosslinked mixture and the cable material are heated to 150-160°C. The viscosity is relatively reduced but still contains active groups, which can fully flow in continuous extrusion equipment (such as extruder die) and tightly wrap around the cable surface. Some initiators or catalysts are activated at this temperature, producing more free radicals or catalytic centers, and further network chains appear inside the material, enhancing the initial mechanical support and avoiding excessive flow. Setting an extrusion speed of 3-8m / min can achieve stable and efficient outer sheath coating in industrial production lines; increasing production while ensuring that the thickness and uniformity of the sheath are controllable.

[0044] S3.3. During the extrusion process, an excitation source is applied to the outer surface of the semi-crosslinked mixture for surface curing, and the curing time is 5 to 60 seconds. The excitation source includes an ultraviolet (UV) lamp with a power of 8 to 12 kW / m or an infrared (IR) lamp with a power of 1 to 4 kW / m. Through UV or IR irradiation, the outermost layer of the semi-crosslinked mixture forms a hard cortex with a high degree of crosslinking within 5 to 60 seconds, which significantly improves the wear resistance and impact resistance of the surface layer; it is of great significance to the protective function of the optical cable sheath. The outer layer reacts faster under high energy excitation, and the interior still maintains a certain flexibility, forming a structural gradient of hard shell and tough core; it can resist external forces and has a certain bending toughness, which meets the fatigue resistance required for laying optical cables. If the power of the ultraviolet lamp reaches 812 kW / m (or the corresponding 80120 W / cm conversion), or the infrared lamp is 1 to 4 kW / m, the surface temperature or free radical polymerization rate can be rapidly increased in a very short time, completing the "surface curing" without delaying the speed of the entire production line. Because the overall protective layer is not completely cross-linked to the deepest layer, the inner layer can still be removed or melted by specific thermal / chemical means during later recycling or reprocessing.

[0045] In one embodiment, in step S3.3, a low-oxygen gas may be introduced, and the oxygen content is less than 5%. A closed or semi-closed cover may be provided, and the oxygen content may be maintained at 1-5% by purging with nitrogen or argon. When active free radicals meet oxygen molecules, peroxyl free radicals are easily formed. These newly formed peroxyl free radicals are often less stable, or may further undergo termination, disproportionation or slow reaction, resulting in rapid consumption or weakening of active free radicals that should have been used for chain growth or crosslinking.

[0046] When the reaction system is in an air environment, the free radicals on the surface of the reaction zone first contact the oxygen molecules, forming an inhibition layer, which makes it difficult for the surface or outer layer of the area to fully cure, or requires higher energy and longer time to achieve the same degree of curing.

[0047] When the oxygen content is significantly reduced, the number of oxygen molecules encountered by active free radicals during the diffusion process is reduced, the probability of forming peroxy free radicals is reduced, and the free radicals can survive longer and continue to participate in polymerization or cross-linking. The increase in the number of free radicals and the extension of their lifespan significantly increase the chain growth rate and cross-linking efficiency, so the free radical polymerization induced by ultraviolet light or infrared heat shows a faster and more thorough curing phenomenon.

[0048] Because it is no longer significantly inhibited by oxygen, the outermost layer of the material can quickly crosslink, cure and form a high-hardness surface, resulting in better gloss, strength and wear resistance. If combined with low oxygen + moderate initiator / auxiliary agent, it can even achieve industrial applications with curing in seconds in a short time.

[0049] The 2,2-dimethoxy-2-phenylethanone and isopropyl-9H-carbazole-1-yl-alkyl ketone derivatives in the initiator are used for ultraviolet light excitation curing, and lauroyl peroxide is used for infrared light excitation curing. Infrared light excitation plays a role of rapid heating, and lauroyl peroxide cooperates with the collective resin to achieve the purpose of rapid curing.

[0050] S3.4. Use air cooling or forced airflow to quickly reduce the outer surface temperature of the semi-cross-linked mixture to 80~100℃, and then place it in a coolant circulation system to reduce the overall temperature of the semi-cross-linked mixture and optical cable material to below room temperature to obtain a thermoplastic optical cable protective material.

[0051] Through air cooling or air flow cooling, the temperature of the solidified surface layer is quickly reduced to 80~100℃, which can inhibit the uneven shrinkage caused by continued overreaction or temperature rise, fix the degree of solidification, and keep the hardness and deformation of the outer layer stable. Segmented cooling (first air cooling to 80~100℃, then cooling liquid to room temperature) makes the temperature difference between the inside and outside of the material relatively controllable during the gradual cooling process, reducing thermal stress concentration or warping. Finally, at room temperature, the material completes the comprehensive structural characteristics of hard shell and tough inside. Its recyclability is due to the fact that the thermoplastic or reversible groups have not been completely consumed, which ensures the subsequent disassembly needs; at the same time, it has sufficient strength and environmental resistance when in use.

[0052] The present invention provides a thermoplastic optical cable protective material, which is made by a preparation method of the thermoplastic optical cable protective material. The thermoplastic optical cable protective material includes a matrix resin, a nano toughening component and a functional filler; wherein: The matrix resin is used to provide mechanical support for the thermoplastic cable shielding material; Nano-toughening components are used to improve the impact absorption and toughness of thermoplastic optical cable protective materials; Functional fillers are used to enhance the mechanical and physical properties of thermoplastic optical cable protective materials.

[0053] The manufactured thermoplastic optical cable protective material can be recycled. The specific recycling method is as follows: Place the thermoplastic optical cable protective material in an acid solution, heat it to about 80-100°C, and keep it for 2-3 hours, so that the reversible bond of the end cap can be reopened, and the outer shell will automatically peel off into a fusible or soluble part; The inner high-toughness fragment and the outer shell material are then filtered and separated, and are modified to be used as a new generation of thermoplastic base material or for preparing injection molded products.

[0054] In order to facilitate recycling, a comonomer is added in step S1.2 of the preparation step of the thermoplastic optical cable protective material, and the comonomer and the matrix resin are mixed with the nano-micelle solution. The general formula of the comonomer is RC(OR′) 2 or RC=NNH 2 , wherein R includes at least one of an alkyl chain, an aryl chain, a pyrrolidinyl group, and a pyridyl group, and R′ includes at least one of an alkyl group, an isopropyl group, a benzyl group, a phenyl group, a glycerol derivative, and a pentaerythritol derivative.

[0055] The acidic solution can be a weakly acidic aqueous solution, which can be a 5-10wt% acetic acid solution and deionized water, with a pH value between 2.5 and 3.5. If the reversible bonds of the copolymer monomers can be hydrolyzed or broken in a weakly acidic environment, the cross-linked structure or the end capping will be decomposed, and the relatively high cross-linked / shell part of the material will first be locally dissolved or cracked, and the inner and outer layers will be relatively separated, and the shell will automatically peel off into meltable or soluble fragments.

[0056] The acidic solution can be a 0.1~0.5 wt% toluenesulfonic acid and ethanol / water mixed solution (volume ratio 1:1). Toluenesulfonic acid can provide relatively strong and localized acid catalysis in the alcohol + water system, which can dissolve the toughening segment or shell segment in the material in layers.

[0057] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a thermoplastic optical cable protective material, characterized in that the steps include: S1, dispersing the nano toughening component to obtain a nano micelle solution, and then placing a matrix resin in the nano micelle solution to obtain a wet-solid mixture; S2, mixing the wet solid mixture and the functional filler, and kneading at a temperature of 120 to 140° C. to obtain a semi-crosslinked mixture; S3, coating the semi-crosslinked mixture on the outer surface of the optical cable material, heating to 150-160° C., applying an excitation source to the semi-crosslinked mixture for surface curing, and cooling to obtain a thermoplastic optical cable protective material.

2. The method for preparing a thermoplastic optical cable protective material according to claim 1, characterized in that: In the step S1, the nano toughening component includes at least one of lactide-caprolactone copolymer oligomer, polyetheretherketone oligomer, and polyurethane elastomer, and the matrix resin includes at least one of polyamide resin, polycarbonate resin, and acrylic resin.

3. The method for preparing a thermoplastic optical cable protective material according to claim 1 or 2, characterized in that: The mass ratio of the nano micelle solution to the matrix resin is 1:3-10.

4. The method for preparing a thermoplastic optical cable protective material according to claim 1, characterized in that: The step S1 comprises: S1.1, placing the nano toughening component in a polar solvent, performing ultrasonic dispersion, adding an initiator and an activation regulator at the same time, the ultrasonic frequency is between 20 and 40 kHz, the ultrasonic power is 300 to 500 W, and the ultrasonic time is 30 to 60 min to obtain a nano micelle solution; S1.2, adding the matrix resin to the nanomicelle solution in batches, stirring at a stirring speed of 100-300 rpm for 30 min to obtain a wet-solid mixture.

5. The method for preparing a thermoplastic optical cable protective material according to claim 4, characterized in that: In the step S1.1, the polar solvent includes at least one of dichloromethane, chloroform, and ethanol, the initiator includes at least one of 2,2-dimethoxy-2-phenylethanone, isopropyl-9H-carbazole-1-yl-alkyl ketone derivatives, and lauroyl peroxide, and the mass percentage of the initiator to the wet solid mixture is 0.1-5%, and the activation regulator includes at least one of triethylamine, dibutyltin dilaurate, and p-toluenesulfonic acid, and the mass percentage of the activation regulator to the wet solid mixture is 0.05-2%.

6. The method for preparing a thermoplastic optical cable protective material according to claim 1, characterized in that: In step S2, the functional filler includes at least one of hard ceramic particles, carbon fibers, and glass fibers. The particle size of the hard ceramic particles is 1-10 μm, the particle size of the carbon fibers is 2-5 mm and / or 10-20 μm, and the particle size of the glass fibers is 3-6 mm and / or 20-30 μm.

7. The method for preparing a thermoplastic optical cable protective material according to claim 1 or 6, characterized in that: The mass ratio of the functional filler to the wet-solid mixture is 1-3:7-9.

8. The method for preparing a thermoplastic optical cable protective material according to claim 1, characterized in that: The step S2 comprises: S2.1, placing the wet solid mixture in a twin-screw extruder, the screw speed of the twin-screw extruder is 30-60 rpm, and firstly performing the first stage of heating and stirring at 100-110°C for 5-10 minutes; S2.2, add the functional filler after the surface modification by the coupling agent, and carry out the second stage of heating and stirring at 120-140°C for 10-20 minutes; S2.

3. Finally, the third stage of heating and stirring is performed at 140-150°C for 3-5 minutes to obtain a semi-crosslinked mixture.

9. The method for preparing a thermoplastic optical cable protective material according to claim 1, characterized in that: The step S3 comprises: S3.1, preheating the optical cable material to 70-80°C, and then coating the semi-crosslinked mixture on the optical cable material; S3.2, heating the semi-crosslinked mixture to 150-160°C, and continuously extruding the semi-crosslinked mixture and the optical cable material at an extrusion speed of 3-8 m / min; S3.3, during the extrusion process, applying an excitation source to the outer surface of the semi-crosslinked mixture for surface curing, the curing time being 5 to 60 seconds, wherein the excitation source comprises an ultraviolet lamp with a power of 8 to 12 kW / m or an infrared lamp with a power of 1 to 4 kW / m; S3.

4. Use air cooling or forced airflow to quickly reduce the outer surface temperature of the semi-crosslinked mixture to 80-100°C, and then place it in a coolant circulation system to reduce the overall temperature of the semi-crosslinked mixture and the optical cable material to below room temperature to obtain a thermoplastic optical cable protective material.

10. A thermoplastic optical cable protective material, characterized in that: The thermoplastic optical cable protective material is prepared by the preparation method of any one of claims 1 to 9, wherein the thermoplastic optical cable protective material comprises a matrix resin, a nano-toughening component and a functional filler; wherein: The matrix resin is used to provide mechanical support for the thermoplastic optical cable protective material; The nano toughening component is used to improve the impact absorption and toughness of the thermoplastic optical cable protective material; The functional filler is used for strengthening the mechanical and physical properties of the thermoplastic optical cable protective material.

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