Water-blocking powder, preparation method thereof, full-dry air-blowing micro-cable and preparation process of full-dry air-blowing micro-cable

Abstract

The invention discloses water-blocking powder and a preparation method thereof, and a full-dry air-blowing micro cable and a preparation process thereof, and belongs to the technical field of optical cable design, and the water-blocking powder comprises high-water-blocking resin, mineral powder filler, a silane coupling auxiliary agent, metal oxide filler and an aluminate coupling agent. According to the present invention, the silane coupling auxiliary agent is adopted to modify the mineral powder filler, and the aluminate coupling agent is adopted to modify the metal oxide filler, such that the compatibility among the mineral powder filler, the metal oxide and the high water-blocking resin is improved, the uniformity of the water-blocking powder is improved, and the water-blocking powder has strong shell forming property and strong adhesion after spraying. The water-blocking powder is not easy to separate from the surface of the optical fiber after being coated on the optical fiber, so that the formed water-blocking layer is more stable in structure and has a better waterproof effect, and the thickness of the water-blocking layer can be effectively reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical cable design, and particularly relates to a water blocking powder and its preparation method, a fully dry blown micro cable and its preparation process. Background Art

[0002] With the continuous development of 5G networks, the resources of underground pipe networks are becoming increasingly tense, and the cost of pipe leasing is increasing. How to build quickly and at low cost has become a problem that operators need to overcome. Blown micro cables are optical cables laid by air blowing. They have the advantages of high fiber density, small diameter and light weight. In traditional oil-filled and semi-dry blown micro cables, the water blocking performance of the micro cable is generally achieved by filling water blocking ointment, but this will increase the weight of the optical cable, improve the difficulty and cost of optical cable transportation, and the oil-filled optical cable must be cleaned of the ointment during fusion splicing, which will greatly increase the construction time and cost, and the construction efficiency is low. While using a fully dry structure, the structure design is simple, the outer diameter is smaller, the weight is lighter, the production cost is low, and the construction and connection are fast and convenient. Therefore, it can further improve the wiring speed, increase the air blowing distance of one-time laying, greatly save the construction cost, and shorten the construction period.

[0003] Although fully dry water blocking powder optical cables have the advantages of light weight, low cost, easy construction, environmental protection and conservation, etc., the existing fully dry water blocking powder optical cables have limitations in water blocking powder filling technology. The main components of the water blocking powder are usually super absorbent polymers (SAP) such as polyacrylamide and sodium polyacrylate. Its powder has a large specific surface area and surface energy, and is in an energy-unstable state, so it is very easy to agglomerate, resulting in an increase in particle size.

[0004] In addition, SAP molecules are strong polar molecules, and hydrogen bond interactions of secondary valence bonds are easily formed between molecules, causing the molecules to attract each other. When the powder absorbs a small amount of water, the water blocking powder forms a hydrogel state, and free ions are generated in the material, which can further increase the surface energy and viscosity of the material after water absorption. However, during the storage and use of this kind of water blocking powder, especially when it absorbs a small amount of water during use, it is very easy to form several small-volume block agglomerates, rather than the continuous shell-like structure expected by people. This makes the water blocking powder unable to completely cover the cable core, increasing the risk of optical cable leakage. Summary of the Invention

[0005] In view of one or more of the above-mentioned defects or improvement requirements of the prior art, the present invention provides a water blocking powder and its preparation method, a fully dry blown micro cable and its preparation process, which can modify the water blocking powder to improve the adhesion and shell-forming properties of the water blocking powder, and optimize the stability and continuity of the formed water blocking layer structure.

[0006] To achieve the above object, in one aspect of the present invention, a water blocking powder is provided, which comprises a high water blocking resin, a mineral powder filler, a silane coupling agent, a metal oxide filler, and an aluminate coupling agent.

[0007] As a further improvement of the present invention, the mass ratio of the high water blocking resin, the mineral powder filler, the silane coupling agent, the metal oxide filler, and the aluminate coupling agent is: (75 - 85):(3 - 13):(2 - 6):(10 - 23):(1 - 2).

[0008] As a further improvement of the present invention, the particle size of the water blocking powder is 150 - 250 mesh.

[0009] As a further improvement of the present invention, the high water blocking resin is any one or a combination of epoxy polyester, polyurethane, and polyacrylic resin.

[0010] As a further improvement of the present invention, the mineral powder filler is any one or a combination of silicate, silica, and granulated blast furnace slag powder.

[0011] As a further improvement of the present invention, the metal oxide filler is any one or a combination of alumina and calcium oxide.

[0012] As a further improvement of the present invention, the silane coupling agent is silane coupling agent Kh570;

[0013] and / or

[0014] the aluminate coupling agent is any one or a combination of di-stearoyl-oxy-isopropyl aluminate and anti-settling aluminate.

[0015] In another aspect of the present invention, a preparation method of a water blocking powder is provided, which comprises the following steps:

[0016] S1: Surface modification of the mineral powder; adding 2 - 6 parts of silane coupling agent to 100 parts of water to prepare a solution; mixing the solution with 3 - 13 parts of silicate and heating and stirring to make the surface of the mineral molecules covered with an organophilic molecular layer; removing the water, and heating and stirring and drying again to obtain the modified mineral powder;

[0017] S2: Surface modification of the metal oxide; mixing 10 - 23 parts of metal oxide powder with 1 - 2 parts of aluminate coupling agent, heating and stirring, and then drying to obtain the modified metal oxide powder;

[0018] S3: Mixing; mixing the modified mineral powder, the modified metal oxide powder, and 75 - 85 parts of high water blocking resin powder, and heating and stirring to obtain a powdery water blocking powder.

[0019] As a further improvement of the present invention, in step (S1), the heating and stirring time after mixing the silane coupling agent solution and silicate is 0.5 to 1 h;

[0020] and / or

[0021] In step (S2), the heating and stirring time of the metal oxide powder and the aluminate coupling agent is 1 to 2 h, and the heating and stirring temperature is 90 - 110 °C;

[0022] and / or

[0023] In step (S3), the heating and stirring temperature of the modified mineral powder, metal oxide powder and high water resistance resin powder is 60 - 85 °C.

[0024] As a further improvement of the present invention, after obtaining the powder in steps (S1), (S2) and (S3), it is sieved again with a sieve of 150 - 250 meshes.

[0025] Another aspect of the present invention provides a fully dry blown microcable including the above-mentioned water blocking powder.

[0026] Another aspect of the present invention provides a preparation process of a fully dry blown microcable, including the following steps:

[0027] (1) The colored optical fiber is released from the pay-off frame and forms an optical fiber bundle through the bunching die;

[0028] (2) Add the water blocking powder described in any one of claims 1 to 10 into the spraying equipment, pass the optical fiber bundle through the spraying equipment at a certain traction speed, and cover the water blocking powder on the surface of the optical fiber bundle;

[0029] (3) The optical fiber bundle covered with the water blocking powder is pulled into the extruder head and extrudes a plastic loose tube through the extrusion die, and the optical fiber loose tube is obtained after stretching, cooling and winding;

[0030] (4) After the strength member and the optical fiber loose tube are respectively released from the pay-off frame, the optical fiber loose tube is SZ stranded around the strength member and then tied with yarn to obtain a cable core;

[0031] (5) The cable core passes through the extrusion die, and an outer sheath is extruded on the outer periphery of the cable core to obtain a fully dry blown microcable.

[0032] As a further improvement of the present invention, the spraying equipment in step (2) is an electrostatic spraying equipment.

[0033] The above-mentioned improved technical features can be combined with each other as long as they do not conflict with each other.

[0034] Generally speaking, compared with the prior art, the beneficial effects of the above technical solutions conceived by the present invention include:

[0035] (1) The water-blocking powder of the present invention is based on a high water-blocking resin as the matrix. By using a silane coupling agent to modify the mineral powder filler and an aluminate coupling agent to modify the metal oxide filler, the compatibility between the mineral powder filler, the metal oxide and the high water-blocking resin is improved, and the uniformity of the water-blocking powder is enhanced. As a result, the water-blocking powder has stronger shell-forming and bonding properties after spraying, and the formed water-blocking layer has a better waterproof effect.

[0036] (2) The water-blocking powder of the present invention selects metal oxides with water absorption properties, such as aluminum oxide, alumina and calcium oxide, which have water absorption properties themselves and can further improve the water absorption of the water-blocking powder.

[0037] (3) For the all-dry blown microcable of the present invention, the modified water-blocking powder is coated on the surface of the optical fiber. Due to its excellent shell-forming and bonding properties, it is not easy to separate from the surface of the optical fiber. The formed water-blocking layer has a stable and continuous structure, which can reduce the thickness of the water-blocking layer, and further reduce the size and weight of the optical fiber sleeve, thus reducing the product cost. Description of the Drawings

[0038] Figure 1 It is a structural diagram of the all-dry blown microcable in the embodiment of the present invention;

[0039] Figure 2 It is a process flow diagram of the preparation of the optical fiber sleeve in the embodiment of the present invention;

[0040] Figure 3 It is a schematic diagram of the water-blocking powder forming a water-blocking powder ring on the optical fiber bundle in the embodiment of the present invention;

[0041] In all the drawings, the same reference numerals represent the same technical features, specifically: 1, outer sheath; 2, water-blocking powder; 3, optical fiber; 4, strength member; 5, loose tube; 6, pay-off stand; 7, stranding frame; 8, spraying equipment; 9, extruder; 10, capstan; 11, take-up; 12, water-blocking powder spraying ring. Detailed Embodiments

[0042] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] Embodiment:

[0044] In the preferred embodiment of the present invention, the water-blocking powder includes a high water-blocking resin, a mineral powder filler, a silane coupling agent, a metal oxide filler, and an aluminate coupling agent.

[0045] Among them, the high water-blocking resin serves as the matrix of the water-blocking powder, and the addition of the mineral powder filler provides mechanical properties and certain water absorption for the water-blocking powder; meanwhile, the silane coupling agent is used to modify the mineral filler to form a hydrophobic organic molecular layer on the surface of the mineral filler, so as to increase the intermolecular interaction, improve the compatibility between the mineral filler and the high water-blocking resin, and enable the mineral filler to be evenly distributed in the water-blocking powder, thereby further improving the stability and continuity of the water-blocking powder after powder spraying.

[0046] Meanwhile, the metal oxide filler is preferably a water-absorbing metal oxide filler, and the metal aluminate coupling agent is used to modify the metal oxide to activate the surface of the metal oxide powder, improve the organic affinity of the powder, reduce the repulsion between the metal oxide and the matrix, and improve the bonding strength between the oxide and the matrix, so that the metal oxide is evenly distributed in the matrix powder, improve the uniformity of the powder, reduce the self-aggregation tendency of the matrix, and make the water-blocking powder have stronger adhesiveness and shell-forming property after powder spraying.

[0047] Preferably, the mass ratio of the high water-blocking resin, the mineral powder filler, the silane coupling agent, the metal oxide filler, and the aluminate coupling agent is: (75-85):(3-13):(2-6):(10-23):(1-2), and the particle size of the water-blocking powder is further preferably 150-250 mesh.

[0048] Preferably, in actual preparation, the high water-blocking resin can be selected from any one or a combination of epoxy polyester, polyurethane, polyacrylic resin, etc.; the mineral powder filler can be selected from any one or a combination of silicate such as calcium silicate, silica, granulated blast furnace slag powder, etc.; the silane coupling agent can be selected from silane coupling agent Kh570, etc.; the metal oxide filler can be selected from any one or a combination of aluminum oxide, alumina, calcium oxide, etc. Among them, aluminum oxide has a water-absorbing porous structure, with the characteristics of moisture absorption but not deliquescence, economy, and easy availability. Alumina and calcium oxide both have water absorption, so the introduction of the metal oxide can further supplement the water absorption performance of the water-blocking powder system and further optimize the water absorption performance of the water-blocking powder; the aluminate coupling agent can be selected from any one or a combination of di-stearoyl oxyisopropyl aluminate, anti-settling aluminate, etc.

[0049] Furthermore, the above modified water-blocking powder is used in an optical cable, especially in the fiber sleeve of a fully dry blown microcable. By utilizing the excellent film-forming property and adhesiveness of the water-blocking powder, after the water-blocking powder is sprayed onto the optical fiber 3, it is not easy to detach from the surface of the optical fiber 3, forming a stable ultra-thin water-blocking layer. This can effectively reduce the spraying thickness of the water-blocking powder, thereby further reducing the size of the sleeve 5, ensuring the consistency of the slack length of the optical fiber 3, and reducing the product cost. Moreover, due to the good film-forming property and adhesiveness of the water-blocking powder, after the water-blocking powder absorbs water and swells, it can form a continuous gel-like structure, which can block the propagation path of water vapor and continue to protect the optical fiber 3, making the sleeve 5 have better waterproof performance.

[0050] Furthermore, the present invention prepares the above water-blocking powder through the following steps:

[0051] S1: Surface modification of mineral powder; Add 2 - 6 parts of silane coupling agent to 100 parts of water to prepare a solution; Add this solution and 3 - 13 parts of mineral powder to a low-speed stirrer, mix and heat-stir for 0.5 - 1 h to cover the surface of mineral molecules with a hydrophobic organic molecular layer; Sieve with 150 - 250 meshes to remove most of the moisture, dry with hot air to remove all the moisture, and then heat-stir and dry again to obtain the modified mineral powder, and sieve with 150 - 250 meshes to prevent powder caking during the drying process and remove particles with too large particle size;

[0052] S2: Surface modification of metal oxide; Add 10 - 23 parts of metal oxide powder and 1 - 2 parts of aluminate coupling agent to a reactor, mix and heat-stir for 1 - 2 h, then dry with hot air and sieve with 150 - 250 meshes to obtain the modified metal oxide powder, improving the adhesiveness and organic affinity of the metal oxide powder;

[0053] Among them, the preferred temperature for mixing and heating the metal oxide powder and the aluminate coupling agent is preferably 90 - 110 °C.

[0054] S3: Mixing; Add the modified mineral powder, metal oxide powder and 75 - 85 parts of high water-blocking resin powder to a stirring device, and heat-stir to obtain a powdery water-blocking powder. It is preferably heated and stirred at a temperature of 60 - 85 °C to ensure drying during the processing, and after mixing evenly, sieve with a 150 - 250 mesh filter to ensure the particle size of the powder.

[0055] In addition, in the above steps S1 - S3, after the processing and drying are completed, the powder needs to be sealed and packaged to prevent moisture absorption and caking.

[0056] The following further illustrates the preparation of the water-blocking powder in combination with specific examples.

[0057] Example 1:

[0058] (1) Add 5 parts of silane coupling agent Kh507 to 100 parts of water to prepare a solution. Add the solution and 10 parts of calcium silicate to a low-speed stirrer, heat and stir for 40 min; sieve through a 150-mesh sieve to remove most of the water, and then dry by blowing air to remove all the water; heat and stir the dried powder again, and sieve through an 180-mesh screen to obtain surface-modified calcium silicate.

[0059] (2) Add 15 parts of metal alumina powder and 1 part of aluminum di(stearoyl) isopropyl aluminate to a reactor, heat and stir for 1.5 h, and the heating temperature is 100 °C; then dry by blowing air, and sieve through a 200-mesh screen after drying to obtain surface-modified metal oxide.

[0060] (3) Add the modified calcium silicate powder, metal alumina powder, and 80 parts of sodium polyacrylate powder to a stirring device, heat and stir at 70 °C to uniformly mix the three powders. After mixing evenly, sieve through a 180-mesh filter screen to obtain the modified water-blocking powder.

[0061] Example 2:

[0062] (1) Add 3 parts of silane coupling agent Kh507 to 100 parts of water to prepare a solution. Add the solution and 10 parts of silica powder to a low-speed stirrer, heat and stir for 1 h; sieve through a 150-mesh sieve to remove most of the water, and then dry by blowing air to remove all the water; heat and stir the dried powder again, and sieve through an 180-mesh screen to obtain surface-modified silica powder.

[0063] (2) Add 15 parts of calcium oxide powder and 2 parts of anti-settling aluminate to a reactor, heat and stir for 1 h, and the heating temperature is 100 °C; then dry by blowing air, and sieve through a 200-mesh screen after drying to obtain surface-modified calcium oxide powder.

[0064] (3) Add the modified silica powder, calcium oxide powder, and 75 parts of sodium polyacrylate powder to a stirring device, heat and stir at 70 °C to uniformly mix the three powders. After mixing evenly, sieve through a 180-mesh filter screen to obtain the modified water-blocking powder.

[0065] Example 3:

[0066] (1) Add 6 parts of silane coupling agent Kh507 to 100 parts of water to prepare a solution. Add the solution and 13 parts of silica powder to a low-speed stirrer, heat and stir for 1 h; sieve through a 150-mesh sieve to remove most of the water, and then dry by blowing air to remove all the water; heat and stir the dried powder again, and sieve through an 180-mesh screen to obtain surface-modified silica powder.

[0067] (2) Add 23 parts of calcium oxide powder and 1.5 parts of anti-settling aluminate ester into the reactor, heat and stir for 1.5 h at a heating temperature of 110 °C; then carry out air drying, and after drying, sieve through a 200-mesh sieve to obtain surface-modified calcium oxide powder.

[0068] (3) Add the modified silica powder, calcium oxide powder, and 85 parts of sodium polyacrylate powder into a stirring device, heat and stir at 85 °C to uniformly mix the three powders, and after uniform mixing, sieve through a 180-mesh filter to obtain the modified water-blocking powder.

[0069] Example 4:

[0070] (1) Add 2 parts of silane coupling agent Kh507 into 100 parts of water to prepare a solution, add the solution and 3 parts of calcium silicate powder into a low-speed stirrer, heat and stir for 1 h; sieve through a 150-mesh sieve to remove most of the moisture, and carry out air drying to remove all the moisture; heat and stir the dried powder again, and sieve through a 180-mesh sieve to obtain surface-modified silica powder.

[0071] (2) Add 10 parts of calcium oxide powder and 1 part of anti-settling aluminate ester into the reactor, heat and stir for 1.5 h at a heating temperature of 90 °C; then carry out air drying, and after drying, sieve through a 200-mesh sieve to obtain surface-modified calcium oxide powder.

[0072] (3) Add the modified calcium silicate powder, calcium oxide powder, and 80 parts of sodium polyacrylate powder into a stirring device, heat and stir at 60 °C to uniformly mix the three powders, and after uniform mixing, sieve through a 180-mesh filter to obtain the modified water-blocking powder.

[0073] Furthermore, the all-dry blowing micro-cable structure in the present invention specifically includes a cable core and an outer sheath 1 coated outside the cable core. The cable core is formed by stranding a plurality of optical fiber sleeves and a central strength member 4. A plurality of optical fibers 3 are arranged in each optical fiber sleeve to form an optical fiber bundle. The above-mentioned water-blocking powder 2 is coated on the surface of the optical fiber 3, and a loose tube 5 is arranged outside the optical fiber bundle.

[0074] Furthermore, the present invention also provides a preparation process for an all-dry blowing micro-cable, which specifically includes the following steps:

[0075] (1) Let the colored optical fiber 3 be released from a pay-off reel 6 and form an optical fiber bundle through a bunching die on a bunching frame 7.

[0076] As Figure 2 shown, in actual setting, after multiple optical fibers 3 are released from the pay-off reel 6, they form an optical fiber bundle after passing through a twisting member and the bunching frame 7 in sequence.

[0077] (2) adding the modified water-blocking powder 2 to the spraying device 8, passing the optical fiber bundle through the spraying device 8 at a certain pulling speed, and covering the surface of the optical fiber bundle with the water-blocking powder 2;

[0078] Preferably, the spraying device 8 is an electrostatic spraying device, and the optical fiber bundle is sprayed by a ring-shaped spray gun on the electrostatic spraying device to form a Figure 3 The water-blocking powder sprayed ring 12 shown in FIG.

[0079] Preferably, the pulling speed of the optical fiber bundle when passing through the electrostatic spraying equipment is 50-200 m / min, and the spraying thickness is 50-120 meshes.

[0080] (3) The optical fiber bundle covered with the water-blocking powder 2 is pulled into the extruder 9, and the plastic loose tube 5 is extruded through the extrusion die, and the optical fiber tube is obtained after stretching, cooling and winding;

[0081] The optical fiber 3 is a single-mode or multi-mode optical fiber, and the plastic loose tube 5 is preferably made of PBT, PP or TPEE, and is a single-layer or double-layer loose tube 5 with a wall thickness of 0.05 to 0.2 mm. Further preferably, the plastic loose tube 5 is a PP material tube with a wall thickness of 0.1 mm.

[0082] like Figure 2 As shown in FIG. 1 , the optical fiber sleeve after being stretched and cooled is pulled to the take-up device 11 by the traction wheel 10 and is wound up by the take-up device 11 and stored for later use.

[0083] (4) After the reinforcing core 4 and the optical fiber sleeve are released through the pay-off frame, the optical fiber sleeve is SZ-twisted around the reinforcing core and then tied with yarn to obtain a cable core;

[0084] The reinforcing core 4 is a metal or non-metal reinforcing member; preferably, the reinforcing core 4 is a steel wire with a diameter of 0.2-1 mm; of course, it can also be a glass fiber reinforced plastic with a diameter of 0.6 mm.

[0085] (5) The cable core is passed through an extrusion die, and an outer sheath 1 is formed on the outer periphery of the cable core by extrusion molding to obtain a fully dry air-blown microcable.

[0086] The outer sheath 1 has low shrinkage performance to prevent the outer sheath 1 from damaging the stability of the optical fiber sleeve in the cable core due to excessive shrinkage force after hot extrusion, thereby reducing the risk of excessive attenuation. The outer sheath 1 is preferably made of PE, PA or PTFE, with an overall wall thickness of 0.2 to 0.5 mm.

[0087] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is 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 water-blocking powder, characterized in that, It includes high water-blocking resin, mineral powder filler, silane coupling additive, metal oxide filler and aluminate coupling agent.

2. The water-blocking powder according to claim 1, wherein The mass ratio of the high water-blocking resin, mineral powder filler, silane coupling additive, metal oxide filler and aluminate coupling agent is: (75-85): (3-13): (2-6): (10-23): (1-2).

3. The water-blocking powder according to claim 2, wherein The particle size of the water-blocking powder is 150-250 meshes.

4. The water-blocking powder according to any one of claims 1 to 3, characterized in that The high water-resistance resin is any one or more combinations of epoxy polyester, polyurethane and polyacrylic acid resin.

5. The water-blocking powder according to any one of claims 1 to 3, characterized in that, The mineral powder filler is any one or more combinations of silicates, silicon dioxide, and granulated blast furnace slag powder.

6. The water-blocking powder according to any one of claims 1 to 3, characterized in that, The metal oxidant filler is any one or more combinations of aluminum oxide and calcium oxide.

7. The water-blocking powder according to any one of claims 1 to 3, characterized in that The silane coupling agent is silane coupling agent Kh570; and / or The aluminate coupling agent is any one or more combinations of distearoyloxyisopropyl aluminate and anti-settling aluminate.

8. A preparation method of a water blocking powder, characterized in that, The steps include: S1: Surface modification of mineral powder: 2 to 6 parts of silane coupling agent are added to 100 parts of water to prepare a solution; the solution is mixed with 3 to 13 parts of silicate and heated and stirred to cover the surface of the mineral molecule with an organophilic molecular layer; the water is removed, and the mixture is heated, stirred and dried again to obtain a modified mineral powder; S2: surface modification of metal oxides: 10 to 23 parts of metal oxide powders are mixed with 1 to 2 parts of aluminate coupling agents, heated, stirred, and then dried to obtain modified metal oxide powders; S3: Mixing: Mix the modified mineral powder, metal oxide powder and 75 to 85 parts of high water-blocking resin powder, and heat and stir to obtain a powdered water-blocking powder.

9. The preparation method of the water-blocking powder according to claim 8, wherein, In step (S1), the heating and stirring time after the silane coupling agent solution and the silicate are mixed is 0.5 to 1 h; and / or In step (S2), the heating and stirring time of the metal oxide powder and the aluminate coupling agent is 1 to 2 hours, and the heating and stirring temperature is 90-110° C.; and / or In step (S3), the heating and stirring temperature of the modified mineral powder, metal oxide powder and high water-resistance resin powder is 60-85°C.

10. The preparation method of the water-blocking powder according to claim 8, characterized in that, After obtaining the powder in steps (S1), (S2) and (S3), the powder is sieved with a filter screen of 150 to 250 meshes.

11. A fully dry blown microcable, characterized in that, The invention comprises the water-blocking powder according to any one of claims 1 to 7.

12. A preparation process for an all-dry blown micro cable, characterized in that, The steps include: (1) The colored optical fiber is released through a pay-off frame and formed into an optical fiber bundle through a bundling mold; (2) adding the water-blocking powder according to any one of claims 1 to 10 into a spraying device, passing the optical fiber bundle through the spraying device at a certain pulling speed, and covering the surface of the optical fiber bundle with the water-blocking powder; (3) pulling the optical fiber bundle covered with water-blocking powder into the extruder head, and extruding a plastic loose tube through an extrusion die, and obtaining an optical fiber loose tube after stretching, cooling, and winding; (4) After the reinforcing core and the optical fiber loose tube are released through the pay-off frame, the optical fiber loose tube is SZ-twisted around the reinforcing core and then tied with yarn to obtain the cable core; (5) The cable core is passed through an extrusion die, and an outer sheath is formed on the outer periphery of the cable core to obtain a fully dry air-blown microcable.

13. The manufacturing process of the fully dry blowing micro cable according to claim 12, characterized in that, The spraying equipment in step (2) is an electrostatic spraying equipment.

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