Moisture-proof cable protective cover material and processing method thereof

Abstract

The present invention discloses a moisture-proof cable protective sheath material and a processing method thereof, wherein the material comprises an insulating wrapping layer, a water-proof barrier layer, a water-proof color developing layer and a moisture-proof protective layer which are sequentially arranged from the inside to the outside, wherein the water-proof barrier layer is composed of a restriction net with an interlayer and water-expandable particles filled in the restriction net interlayer, the water-proof color developing layer is made of water-discolorable ink, and the moisture-proof protective layer is made of a transparent or translucent material. The cable protective sheath material is provided with daily moisture-proof protection through the moisture-proof protective layer, and when water vapor enters the inside of the cable, it can be displayed through the water-proof color developing layer to remind people to handle it in time, and at the same time, the water-proof barrier layer is used to block it for the first time to prevent the water vapor from continuing to penetrate inward and contacting the cable core, causing a safety accident.

Description

Technical Field

[0001] The invention relates to the technical field of cable protective sleeves, and in particular to a moisture-proof cable protective sleeve material and a processing method thereof. Background Art

[0002] At present, with the development of science and technology, people's demand for cables is increasing. Cables are a common data signal transmission device with the advantages of large communication capacity, high transmission stability and good confidentiality. Cables are generally composed of a conductive core and a cable protective sheath. Most of the existing cable protective sheaths use some common polymers, which do not have a moisture-proof effect. Water vapor will corrode the protective layer, causing water vapor to enter the cable, seriously affecting the service life and safety of the cable. Summary of the invention

[0003] The object of the present invention is to provide a moisture-proof cable protective sheath material and a processing method thereof, which solves the problem that the existing cable has a poor moisture-proof effect.

[0004] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0005] A moisture-proof cable protective sheath material comprises an insulating wrapping layer, a water-proof barrier layer, a water-proof color developing layer and a moisture-proof protective layer which are arranged in sequence from the inside to the outside, wherein the water-proof barrier layer is composed of a restricting net with an interlayer and water-swellable particles filled in the restricting net interlayer, the water-proof color developing layer is made of water-proof color-changing ink, and the moisture-proof protective layer is made of a transparent or translucent material.

[0006] A further improvement is that the insulating wrapping layer is made of flame-retardant, low-smoke, halogen-free polyolefin material.

[0007] A further improvement is that the restriction network comprises:

[0008] A double-layer stainless steel mesh, wherein a sandwich is formed between the double-layer stainless steel mesh;

[0009] The modified agave fiber threads alternately shuttle between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads.

[0010] A further improvement is that the double-layer stainless steel mesh is formed by interweaving horizontal and vertical stainless steel wires, and the interweaving points are fused by hot pressing to form a fixed grid on the surface of the double-layer stainless steel mesh for the modified agave fiber wires to shuttle through, and the grid size is smaller than the size of the water-swelling particles.

[0011] A further improvement is that the modified agave fiber yarn is made by subjecting agave fibers to HCl ventilation treatment, heat treatment, and pressing treatment, and then plying.

[0012] A further improvement is that, in terms of mass percentage, the raw materials for preparing the water-swellable particles include: 60-75% natural rubber, 20-35% highly absorbent resin, 1-4% sulfur and 0.5-2% dibenzothiazole disulfide.

[0013] A further improvement is that the moisture-proof protective layer is made of transparent nylon.

[0014] The present invention also provides a method for processing a moisture-proof cable protective sheath material, the steps comprising:

[0015] Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles;

[0016] Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

[0017] A further improvement is that in step 1, the specific operation of preparing the restraining net with interlayer is:

[0018] (1) selecting stainless steel wires with a diameter of 0.1-0.3 mm, interweaving the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fusing the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.5-0.8 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use;

[0019] (2) preparing agave fiber, immersing the agave fiber in negative ion water, and simultaneously introducing HCl gas in an amount of 20-30 mg / L into the negative ion water in a dispersed manner, taking out the agave fiber after the aeration is completed and cleaning it, and then spraying the agave fiber with hot water at 85-98° C. for 0.5-3 h, and finally drying the agave fiber with hot air at 70-80° C. to obtain modified agave fiber, bundling the modified agave fiber into bundles, and passing through (8-12)×10 5 Pa for 5-12 days, taking the modified agave fiber after pressing, breaking it up, and performing multiple plying processes to obtain modified agave fiber yarn for use;

[0020] (3) The modified agave fiber threads are alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

[0021] The beneficial effects of the present invention are:

[0022] (1) The cable protective sheath material provides daily moisture-proof protection through the moisture-proof protective layer. When water vapor enters the cable, it can be displayed through the water-sensitive color layer to remind people to deal with it in time. At the same time, the water-sensitive barrier layer can be used to block it for the first time to prevent water vapor from continuing to penetrate inward and contacting the cable core, causing safety accidents.

[0023] (2) The water barrier layer in the cable protective sheath material adopts a restriction net made of a double-layer stainless steel mesh and modified agave fiber filaments alternately shuttling between the double-layer stainless steel mesh, which can reduce the interlayer spacing after contact with water and shrink the storage space of the water-swelling particles. The water-swelling particles themselves swell when contacted with water. Under the combined effect, the water barrier layer is completely closed in a very short time, and the barrier protection effect is outstanding. Among them, after the modified agave fiber filaments are treated with HCl ventilation, heat treatment, and pressing, the microstructure is strengthened and the density is improved, so that the tensile strength is significantly enhanced, and it is prevented from being broken under the action of the expansion force. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a cross-sectional view of the moisture-proof cable protective sheath material in Example 1 of the present invention;

[0025] Figure 2 It is a cross-sectional view of the limiting net in Example 1 of the present invention. DETAILED DESCRIPTION

[0026] The present application is further described in detail below in conjunction with the embodiments. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0027] 1. Preparation of experimental raw materials:

[0028] ① Cable core: Take Φ8.00mm copper rod and draw it into round copper single wire through multiple stretching. The round copper single wire is twisted and pressed tightly. It is arranged according to the typical structure of the conductor (from inside to outside: 1+6+12+18). It is layered and pressed, and the compression coefficient is not less than 0.9 to obtain the cable core conductor that meets the requirements of GB / T3956.

[0029] ② Insulation wrapping material: flame retardant low smoke halogen-free polyolefin, purchased from Shenzhen Boruilian Rubber and Plastic Material Co., Ltd.

[0030] ③ Water-chromogenic layer material: water-chromatic ink, purchased from Shenzhen Bianse Technology Co., Ltd.

[0031] ④ Moisture-proof protective layer material: transparent nylon, purchased from Yuyao Huibang Engineering Plastics Co., Ltd.

[0032] ⑤ Agave fiber: Take agave leaves, soak them in 2.5mol / L hydrochloric acid solution at 38℃ for 2h, rinse them with clean water, and then soak them in clean water at a bath ratio of 5:1. Then, at 50℃, use pectinase at a mass ratio of agave leaves: pectinase = 5:1 to enzymatically degummed the agave leaves obtained after soaking, and hydrolyze them for 2.5h. Then heat it to 95℃, rinse it with hot water for 25min, and then dehydrate and dry it; then soak it in 5g / L NaOH solution at a bath ratio of 10:1, and refine it for 2h, then wash it with water for 30min, and then loosen and sort it out to obtain agave fiber.

[0033] 2. Implementation Plan

[0034] Example 1

[0035] like Figure 1 As shown, a moisture-proof cable protective sheath material comprises an insulating sheath 1, a water-proof barrier layer 2, a water-proof color-developing layer 3 and a moisture-proof protective layer 4 which are arranged in sequence from the inside to the outside, wherein the insulating sheath 1 is made of a flame-retardant low-smoke halogen-free polyolefin material, the water-proof barrier layer 2 is composed of a restricting net with an interlayer and water-swellable particles 23 filled in the restricting net interlayer, the water-proof color-developing layer 3 is made of water-discoloring ink, and the moisture-proof protective layer 4 is made of transparent nylon.

[0036] like Figure 2 As shown, in this embodiment, the restriction network includes:

[0037] A double-layer stainless steel mesh 21, a sandwich is formed between the double-layer stainless steel mesh 21, the double-layer stainless steel mesh 21 is formed by interweaving horizontal and vertical stainless steel wires, and the interweaving points are fused by hot pressing to form a fixed grid on the mesh surface of the double-layer stainless steel mesh 21, and the grid size is smaller than the size of the water-swellable particles 23;

[0038] The stainless steel wire drawing 22 alternately shuttles between the double-layer stainless steel meshes, and the double-layer stainless steel mesh 21 is pulled and fixed by the stainless steel wire drawing 22 .

[0039] In this embodiment, the water-swellable particles 23 are prepared from raw materials including: 70% natural rubber, 25% highly absorbent resin (sodium polyacrylate resin, the same below), 3% sulfur and 2% dibenzothiazole disulfide, which are mixed and granulated according to conventional processes.

[0040] The preparation method of the moisture-proof cable protective sheath material comprises the following steps:

[0041] Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles;

[0042] The specific operation of preparing the restriction network with interlayer is as follows:

[0043] (1) Selecting stainless steel wires with a diameter of 0.2 mm, interweaving the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fusing the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.6 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use;

[0044] (2) Select stainless steel wire drawing with a diameter of 0.2 mm for use;

[0045] (3) The stainless steel wire drawing is alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the stainless steel wire drawing to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

[0046] Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

[0047] Example 2

[0048] A moisture-proof cable protective sheath material comprises an insulating sheath, a water-proof barrier layer, a water-proof color developing layer and a moisture-proof protective layer which are arranged in sequence from the inside to the outside, wherein the insulating sheath is made of a flame-retardant low-smoke halogen-free polyolefin material, the water-proof barrier layer is composed of a restricting net with an interlayer and water-expandable particles filled in the restricting net interlayer, the water-proof color developing layer is made of water-proof color-changing ink, and the moisture-proof protective layer is made of a transparent nylon material.

[0049] In this embodiment, the restriction network includes:

[0050] A double-layer stainless steel mesh, wherein a sandwich is formed between the double-layer stainless steel mesh;

[0051] The agave fiber threads alternately shuttle between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the agave fiber threads.

[0052] In this embodiment, the raw materials for preparing the water-swellable particles include: 70% natural rubber, 25% highly absorbent resin, 3% sulfur and 2% dibenzothiazole disulfide, which are mixed and granulated according to conventional processes.

[0053] The preparation method of the moisture-proof cable protective sheath material comprises the following steps:

[0054] Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles;

[0055] The specific operation of preparing the restriction network with interlayer is as follows:

[0056] (1) Selecting stainless steel wires with a diameter of 0.2 mm, interweaving the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fusing the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.6 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use;

[0057] (2) selecting agave fiber and performing three plying processes, namely 3-in-1, 15-in-1, and 7-in-1, with the twist directions being S twist, S twist, and Z twist, and the twist degrees being 120 twists / m, 90 twists / m, and 75 twists / m, respectively, to obtain agave fiber yarns having a diameter close to that of the stainless steel wire for later use;

[0058] (3) The agave fiber threads are alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the agave fiber threads to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

[0059] Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

[0060] Example 3

[0061] A moisture-proof cable protective sheath material comprises an insulating sheath, a water-proof barrier layer, a water-proof color developing layer and a moisture-proof protective layer which are arranged in sequence from the inside to the outside, wherein the insulating sheath is made of a flame-retardant low-smoke halogen-free polyolefin material, the water-proof barrier layer is composed of a restricting net with an interlayer and water-expandable particles filled in the restricting net interlayer, the water-proof color developing layer is made of water-proof color-changing ink, and the moisture-proof protective layer is made of a transparent nylon material.

[0062] In this embodiment, the restriction network includes:

[0063] A double-layer stainless steel mesh, wherein a sandwich is formed between the double-layer stainless steel mesh;

[0064] The modified agave fiber threads alternately shuttle between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads.

[0065] In this embodiment, the raw materials for preparing the water-swellable particles include: 70% natural rubber, 25% highly absorbent resin, 3% sulfur and 2% dibenzothiazole disulfide, which are mixed and granulated according to conventional processes.

[0066] The preparation method of the moisture-proof cable protective sheath material comprises the following steps:

[0067] Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles;

[0068] The specific operation of preparing the restriction network with interlayer is as follows:

[0069] (1) Selecting stainless steel wires with a diameter of 0.2 mm, interweaving the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fusing the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.6 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use;

[0070] (2) Select agave fibers, bundle them into bundles, and pass them through a 10×10 5 Pa tightening pressure pressing for 8 days, taking the pressed agave fiber and breaking it up, and performing three plying processes, namely 3 in 1, 15 in 1, and 7 in 1, respectively, the twist directions are S twist, s twist, and Z twist, respectively, and the twist degrees are 120 twists / m, 90 twists / m, and 75 twists / m, respectively, to obtain modified agave fiber yarns with a diameter close to that of stainless steel wire for use;

[0071] (3) The modified agave fiber threads are alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

[0072] Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

[0073] Example 4

[0074] A moisture-proof cable protective sheath material comprises an insulating sheath, a water-proof barrier layer, a water-proof color developing layer and a moisture-proof protective layer which are arranged in sequence from the inside to the outside, wherein the insulating sheath is made of a flame-retardant low-smoke halogen-free polyolefin material, the water-proof barrier layer is composed of a restricting net with an interlayer and water-expandable particles filled in the restricting net interlayer, the water-proof color developing layer is made of water-proof color-changing ink, and the moisture-proof protective layer is made of a transparent nylon material.

[0075] In this embodiment, the restriction network includes:

[0076] A double-layer stainless steel mesh, wherein a sandwich is formed between the double-layer stainless steel mesh;

[0077] The modified agave fiber threads alternately shuttle between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads.

[0078] In this embodiment, the raw materials for preparing the water-swellable particles include: 70% natural rubber, 25% highly absorbent resin, 3% sulfur and 2% dibenzothiazole disulfide, which are mixed and granulated according to conventional processes.

[0079] The preparation method of the moisture-proof cable protective sheath material comprises the following steps:

[0080] Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles;

[0081] The specific operation of preparing the restriction network with interlayer is as follows:

[0082] (1) Selecting stainless steel wires with a diameter of 0.2 mm, interweaving the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fusing the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.6 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use;

[0083] (2) selecting agave fiber, immersing the agave fiber in negative ion water, and simultaneously introducing HCl gas in an amount of 25 mg / L into the negative ion water in a dispersed manner, taking out the agave fiber after the ventilation is completed and cleaning it, and then spraying the agave fiber with 90° C. hot water for 2 h, and finally drying the agave fiber with 75° C. hot air to obtain modified agave fiber, and performing three plying processes using the modified agave fiber, namely 3 in 1, 15 in 1, and 7 in 1, respectively, with the twist directions being S twist, S twist, and Z twist, respectively, and the twist degrees being 120 twists / m, 90 twists / m, and 75 twists / m, respectively, to obtain modified agave fiber with a diameter close to that of stainless steel wire for standby use;

[0084] (3) The modified agave fiber threads are alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

[0085] Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

[0086] Example 5

[0087] A moisture-proof cable protective sheath material comprises an insulating sheath, a water-proof barrier layer, a water-proof color developing layer and a moisture-proof protective layer which are arranged in sequence from the inside to the outside, wherein the insulating sheath is made of a flame-retardant low-smoke halogen-free polyolefin material, the water-proof barrier layer is composed of a restricting net with an interlayer and water-expandable particles filled in the restricting net interlayer, the water-proof color developing layer is made of water-proof color-changing ink, and the moisture-proof protective layer is made of a transparent nylon material.

[0088] In this embodiment, the restriction network includes:

[0089] A double-layer stainless steel mesh, wherein a sandwich is formed between the double-layer stainless steel mesh;

[0090] The modified agave fiber threads alternately shuttle between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads.

[0091] In this embodiment, the raw materials for preparing the water-swellable particles include: 70% natural rubber, 25% highly absorbent resin, 3% sulfur and 2% dibenzothiazole disulfide, which are mixed and granulated according to conventional processes.

[0092] The preparation method of the moisture-proof cable protective sheath material comprises the following steps:

[0093] Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles;

[0094] The specific operation of preparing the restriction network with interlayer is as follows:

[0095] (1) Selecting stainless steel wires with a diameter of 0.2 mm, interweaving the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fusing the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.6 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use;

[0096] (2) Select agave fibers, immerse them in negative ion water, and disperse HCl gas at an amount of 25 mg / L into the negative ion water. After the aeration, take out the agave fibers and clean them. Then, spray the agave fibers with 90°C hot water for 2 h. Finally, dry the agave fibers with 75°C hot air to obtain modified agave fibers. Bundle the modified agave fibers into bundles and pass them through a 10×10 5 Pa tightening pressure pressing for 8 days, taking the pressed agave fiber and breaking it up, using the modified agave fiber to carry out three times of twisting processing, which are 3 in 1, 15 in 1, and 7 in 1, respectively, the twist directions are S twist, S twist, and Z twist, respectively, and the twist degrees are 120 twists / m, 90 twists / m, and 75 twists / m, respectively, to obtain modified agave fiber yarn with a diameter close to that of stainless steel wire for use;

[0097] (3) The modified agave fiber threads are alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

[0098] Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

[0099] Example 6

[0100] A moisture-proof cable protective sheath material comprises an insulating sheath, a water-proof barrier layer, a water-proof color developing layer and a moisture-proof protective layer which are arranged in sequence from the inside to the outside, wherein the insulating sheath is made of a flame-retardant low-smoke halogen-free polyolefin material, the water-proof barrier layer is composed of a restricting net with an interlayer and water-expandable particles filled in the restricting net interlayer, the water-proof color developing layer is made of water-proof color-changing ink, and the moisture-proof protective layer is made of a transparent nylon material.

[0101] In this embodiment, the restriction network includes:

[0102] A double-layer stainless steel mesh, wherein a sandwich is formed between the double-layer stainless steel mesh;

[0103] The modified agave fiber threads alternately shuttle between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads.

[0104] In this embodiment, the raw materials for preparing the water-swellable particles include: 60% natural rubber, 35% highly absorbent resin, 4% sulfur and 1% dibenzothiazole disulfide, which are mixed and granulated according to conventional processes.

[0105] The preparation method of the moisture-proof cable protective sheath material comprises the following steps:

[0106] Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles;

[0107] The specific operation of preparing the restriction network with interlayer is as follows:

[0108] (1) Selecting stainless steel wires with a diameter of 0.1 mm, interweaving the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fusing the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.5 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use;

[0109] (2) Select agave fibers, immerse them in negative ion water, and disperse HCl gas at an amount of 20 mg / L into the negative ion water. After the aeration, take out the agave fibers and clean them. Then, spray them with 85°C hot water for 3 hours. Finally, dry them with 70°C hot air to obtain modified agave fibers. Bundle the modified agave fibers into bundles and pass them through 8×10 5Pa tightening pressure pressing for 12 days, taking the pressed agave fiber and breaking it up, using the modified agave fiber to perform three times of twisting processing, which are 3 in 1, 19 in 1, and 5 in 1, respectively, the twist directions are S twist, s twist, and Z twist, respectively, and the twist degrees are 120 twists / m, 90 twists / m, and 75 twists / m, respectively, to obtain modified agave fiber yarns with a diameter close to that of stainless steel wire for use;

[0110] (3) The modified agave fiber threads are alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

[0111] Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

[0112] Example 7

[0113] A moisture-proof cable protective sheath material comprises an insulating sheath, a water-proof barrier layer, a water-proof color developing layer and a moisture-proof protective layer which are arranged in sequence from the inside to the outside, wherein the insulating sheath is made of a flame-retardant low-smoke halogen-free polyolefin material, the water-proof barrier layer is composed of a restricting net with an interlayer and water-expandable particles filled in the restricting net interlayer, the water-proof color developing layer is made of water-proof color-changing ink, and the moisture-proof protective layer is made of a transparent nylon material.

[0114] In this embodiment, the restriction network includes:

[0115] A double-layer stainless steel mesh, wherein a sandwich is formed between the double-layer stainless steel mesh;

[0116] The modified agave fiber threads alternately shuttle between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads.

[0117] In this embodiment, the raw materials for preparing the water-swellable particles include: 75% natural rubber, 21% super absorbent resin, 2% sulfur and 2% dibenzothiazole disulfide, which are mixed and granulated according to conventional processes.

[0118] The preparation method of the moisture-proof cable protective sheath material comprises the following steps:

[0119] Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles;

[0120] The specific operation of preparing the restriction network with interlayer is as follows:

[0121] (1) selecting stainless steel wires with a diameter of 0.3 mm, interweaving the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fusing the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.8 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use;

[0122] (2) Select agave fibers, immerse them in negative ion water, and disperse HCl gas at an amount of 30 mg / L into the negative ion water. After the aeration, take out the agave fibers and clean them. Then, spray the agave fibers with 98°C hot water for 0.5 h. Finally, dry the agave fibers with 80°C hot air to obtain modified agave fibers. Bundle the modified agave fibers into bundles and pass them through a 12×10 5 Pa tightening pressure pressing for 5 days, taking the pressed agave fiber and breaking it up, using the modified agave fiber to carry out three times of twisting processing, which are 3 in 1, 13 in 1, and 9 in 1 respectively, the twist directions are S twist, S twist, and Z twist respectively, and the twist degrees are 120 twists / m, 90 twists / m, and 75 twists / m respectively, to obtain modified agave fiber yarn with a diameter close to that of stainless steel wire for use;

[0123] (3) The modified agave fiber threads are alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

[0124] Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

[0125] 3. Performance test

[0126] (1) Water shrinkage test

[0127] Take the stainless steel wire (or agave fiber wire, or modified agave fiber wire) obtained in Examples 1-7, cut into 50 mm long samples, place each sample in the same water vapor environment (90% saturated water vapor), take out the sample after 1 minute, measure its contraction length, and calculate the length contraction rate of each test, contraction rate = (original length - contraction length) / original length × 100%, the calculation results are shown in Table 1:

[0128] Table 1: Shrinkage test results

[0129]

[0130] It can be seen from Table 1 that the agave fiber filaments (or modified agave fiber filaments) used in the embodiments of the present invention have good water shrinkage performance, that is, the effects of HCl ventilation treatment, heat treatment, pressing treatment and other processes on the water shrinkage performance are negligible.

[0131] (2) Tensile strength and elongation at break test

[0132] Take the agave fiber (or modified agave fiber) sample obtained in Examples 2-7, place the sample in distilled water at a temperature of 20°C, immerse the sample completely, take it out after immersion for 0.5 minutes, use a fiber mechanics tester, load each sample on the instrument fixture in turn and keep it immersed in water all the time, make fine adjustments to make the load direction consistent with the long axis direction of the sample, and add a preload of 10mN; load at a uniform speed (0.04mm / min) until the sample breaks, record the breaking load and displacement elongation, the breaking load is accurate to 0.1mN, and the displacement elongation is accurate to 0.1pm; after the test, cut the broken fiber segment, and use an optical microscope to measure the cross-sectional area of ​​the fiber. Finally, according to the recorded data, calculate the tensile strength and elongation at break, and the calculation formula is:

[0133] Tensile strength: σ = F / S, F is the breaking load, unit N, S is the cross-sectional area of ​​the specimen, unit mm 2 ;

[0134] Elongation at break: ε = ΔL / L, ΔL is the displacement elongation within the span L when the specimen is tensilely broken, in mm, and L is the span, in mm.

[0135] The calculation results of tensile strength and elongation at break are shown in Table 1:

[0136] Table 2: Tensile strength and elongation at break test results

[0137]

[0138] As can be seen from Table 2, the tensile strength of the common agave fiber filaments used in Example 2 of the present invention is poor, only 79.2 MPa, which does not meet the requirements of tightening and expanding particles, while the modified agave fiber filaments in Examples 5-7 have undergone HCl ventilation treatment, heat treatment, and pressing treatment, so that the tensile strength exceeds 190 MPa, which is significantly improved. In addition, it can be seen from Examples 3 and 4 that HCl ventilation treatment, heat treatment, and pressing treatment all play an important role in improving the tensile strength. Only one or two of the treatment processes are not enough to make the modified agave fiber filaments meet the requirements for tensile strength.

[0139] (3) Moisture resistance test

[0140] The water-receiving barrier layers in Examples 1-7 were taken out separately, and the water-receiving barrier layers were laid flat to obtain a plurality of 2 cm×5 cm plane layers. A plurality of long conduits with a square cross-section of 2 cm×2 cm were then taken, and water vapor flowed through the conduits. The water vapor flow rate was controlled to be 10 L / min. Ten 2 cm×5 cm rectangular notches were opened on one side of the conduits, and the notches on each conduit were sealed with the plane layer of the water-receiving barrier layer in the same example. The wetting of the outer surface of the plane layer was observed, and the number of wetted plane layers on each conduit after different time lengths was counted.

[0141] The statistical results are shown in Table 3:

[0142] Table 3: Moisture resistance test results

[0143] Duration 5min 10min 30min 1h 3h 12h 48h Example 1 0 1 3 3 3 3 4 Example 2 0 0 0 0 2 5 8 Example 3 0 0 0 0 1 3 4 Example 4 0 0 0 0 1 2 3 Example 5 0 0 0 0 0 0 0 Example 6 0 0 0 0 0 0 0 Example 7 0 0 0 0 0 0 0

[0144] As can be seen from Table 3, the restriction net in Example 1, which is pulled and fixed by stainless steel wire, cannot reduce the limited space when it encounters water. It only relies on the self-expansion effect of the water-swelling particles. The moisture-proof effect is general, and it becomes wet after 10 minutes. The reason may be that even if the particles in some areas expand, they cannot completely block the gaps. The restriction net in Example 2, which is pulled and fixed by ordinary agave fiber, has the worst moisture-proof effect. The reason is that although the agave fiber can shrink when it encounters water, its own tensile strength is poor. As time goes by, more water-swelling particles gradually expand, making it impossible for the restriction net to continue to wrap and restrict. The agave fiber is broken, causing the water-swelling particles to loosen and lose the blocking effect. In Example 3 and Example 4, HCl ventilation treatment, heat treatment and pressing treatment all play an important role in improving the tensile strength. Only one or two of the treatment processes are used, which is not enough to make the modified agave fiber reach the required tensile strength. Embodiments 5-7 are the best solutions of the present invention. Even after 48 hours, there is no case of wetting. On the one hand, it protects the cable core, and on the other hand, it provides time guarantee for processing the color-developing area cable.

[0145] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A moisture-proof cable protective sheath material, characterized in that: It includes an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture-proof protective layer arranged in sequence from the inside to the outside, wherein the water barrier layer is composed of a restriction net with an interlayer and water-expandable particles filled in the interlayer of the restriction net, the water color developing layer is made of water-discoloring ink, and the moisture-proof protective layer is made of a transparent or translucent material; The restriction network includes: A double-layer stainless steel mesh, wherein a sandwich is formed between the double-layer stainless steel mesh; The modified agave fiber threads alternately shuttle between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber threads.

2. A moisture-proof cable protective sheath material according to claim 1, characterized in that: The insulating wrapping layer is made of flame-retardant, low-smoke, halogen-free polyolefin material.

3. A moisture-proof cable protective sheath material according to claim 1, characterized in that: The double-layer stainless steel mesh is formed by interweaving transverse and longitudinal stainless steel wires, and the interweaving points are fused by hot pressing to form a fixed grid for the modified agave fiber to shuttle on the surface of the double-layer stainless steel mesh, and the grid size is smaller than the water-swelling particle size.

4. A moisture-proof cable protective sheath material according to claim 1, characterized in that: The modified agave fiber yarn is prepared by subjecting agave fibers to HCl ventilation treatment, heat treatment, and pressing treatment, and then plying.

5. The moisture-proof cable protective sheath material according to claim 1, characterized in that: In terms of mass percentage, the raw materials for preparing the water-swellable particles include: 60-75% natural rubber, 20-35% highly absorbent resin, 1-4% sulfur and 0.5-2% dibenzothiazole disulfide.

6. A moisture-proof cable protective sheath material according to claim 1, characterized in that: The moisture-proof protective layer is made of transparent nylon.

7. A method for processing the moisture-proof cable protective sheath material according to any one of claims 1 to 6, characterized in that the steps include: Step 1: preparing an insulating wrapping layer, a water barrier layer, a water color developing layer and a moisture proof protective layer respectively, wherein the preparation step of the water barrier layer is: first preparing a restriction net with an interlayer, and then filling the interlayer of the restriction net with water swelling particles; Step 2: Wrap the insulating wrapping layer, the water barrier layer, the water color developing layer and the moisture-proof protective layer on the outside of the cable core in sequence from the inside to the outside to form a moisture-proof cable protective sheath material.

8. The method for processing moisture-proof cable protective sheath material according to claim 7, characterized in that: In step 1, the specific operation of preparing the restriction network with interlayer is: (1) Select stainless steel wires with a diameter of 0.1-0.3 mm, interweave the stainless steel wires horizontally and vertically to form a stainless steel mesh, and fuse the interweaving points by hot pressing to form a rectangular fixed grid with a size of 0.5-0.8 mm on the surface of the stainless steel mesh, thereby obtaining a double-layer stainless steel mesh for standby use; (2) preparing agave fibers, immersing the agave fibers in negative ion water, and simultaneously introducing HCl gas dispersedly into the negative ion water at an amount of 20-30 mg / L, taking out the agave fibers after the aeration is completed and cleaning them, and then spraying the agave fibers with hot water at 85-98° C. for 0.5-3 h, and finally drying the agave fibers with hot air at 70-80° C. to obtain modified agave fibers, bundling the modified agave fibers into bundles, and passing through (8-12)×10 5 Pa for 5-12 days, taking the modified agave fiber after pressing, breaking it up, and performing multiple plying processes to obtain modified agave fiber yarn for use; (3) The modified agave fiber filaments are alternately passed between the double-layer stainless steel meshes, and the double-layer stainless steel meshes are pulled and fixed by the modified agave fiber filaments to form a sandwich between the double-layer stainless steel meshes, thereby obtaining the restriction mesh.

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