Animal-resistant optical cable

Abstract

The present invention belongs to the field of optical cables, and in particular relates to an animal-resistant optical cable. The cable comprises a cable core and a sheath material, the sheath material comprising the following components: 100 parts by weight of rubber, 6-12 parts by weight of a mixture of carbon black and white carbon black, 1-3 parts by weight of an oxide filler, 1-5 parts by weight of an antioxidant, 2-5 parts by weight of a vulcanizing agent, 1-2 parts by weight of an accelerator, and 3-8 parts by weight of a plasticizer. The present invention utilizes three types of fillers to achieve a delayed hardening effect when the rubber outer sheath is used for animal-resistant cable gnawing. This provides excellent gnawing resistance while maintaining transportability and providing excellent mechanical protection for the cable core.

Description

Technical Field

[0001] The invention belongs to the field of optical cables, and in particular relates to an optical cable that is resistant to animal gnawing. Background Art

[0002] Gnawing damage is a common and important form of cable damage. Outdoor optical cables, and in some areas, embedded indoor optical cables, are susceptible to gnawing damage from rodents such as squirrels and mice.

[0003] Currently, a simple and effective way to protect optical cables from being bitten is to increase the surface hardness of the cables, such as by adding an outer armor layer. However, this type of protection is still prone to aging and failure due to extended service life, and this fully rigid structure is actually extremely disadvantageous during the preparation and transportation of optical cables. Summary of the Invention

[0004] In order to solve the problems that the existing anti-bite optical cable has poor physical protection, the actual service life of the fully hardened structure is relatively limited, and it causes disadvantages in the preparation and transportation of the optical cable, the present invention provides an animal-proof optical cable.

[0005] The main objectives of the present invention are:

[0006] 1. It can significantly improve the anti-bite performance of optical cables;

[0007] 2. The unique hardened protection form can reduce the inconvenience of optical cable preparation and transportation;

[0008] 3. It can repel rodents.

[0009] To achieve the above objectives, the present invention adopts the following technical solutions.

[0010] Animal-resistant optical cables, including cable core and sheath materials,

[0011] The sheath material comprises the following components:

[0012] 100 parts by weight of rubber, 6-12 parts by weight of a mixture of carbon black and white carbon black, 1-3 parts by weight of an oxide filler, 1-5 parts by weight of an antioxidant, 2-5 parts by weight of a vulcanizing agent, 1-2 parts by weight of an accelerator, and 3-8 parts by weight of a plasticizer.

[0013] As a preference,

[0014] The rubber is natural rubber and / or styrene-butadiene rubber and / or butadiene rubber.

[0015] As a preference,

[0016] The mass percentage of carbon black in the mixture of carbon black and white carbon black is 5-10wt% or 85-95wt%;

[0017] When the carbon black content is 5 to 10 wt%, the weight portion of the mixture used is 9 to 12 weight portions;

[0018] When the carbon black content is 85-95 wt%, the weight portion of the mixture used is 6-9 weight portions.

[0019] As a preference,

[0020] The oxide filler is calcium oxide.

[0021] As a preference,

[0022] The preparation method of the sheath material comprises:

[0023] 1) The rubber is subjected to plasticizing treatment until it is rolled and then cut with a knife, and an antioxidant and a dispersant are added;

[0024] 2) Continue to mix and knead, first add oxide filler during the mixing process, then alternately add plasticizer and a mixture of carbon black and white carbon black, and finally add vulcanizing agent and accelerator. After the mixing is completed, vulcanize the material and obtain the anti-bite sheath material.

[0025] As a preference,

[0026] Step 1) The dispersant is triglyceride and / or pentaerythritol tristearate.

[0027] As a preference,

[0028] Step 2) The plasticizer and the mixture of carbon black and white carbon black are added at least three times, and the amount added each time does not exceed 45wt% of the total amount added.

[0029] As a preference,

[0030] Fatty acid soap is added to the mixture of carbon black and white carbon black.

[0031] The core of the present invention is to use a special sheath material as the outer sheath material of the optical cable, which can be used in conjunction with any existing cable core structure. Therefore, its structure will not be described in detail. The process of molding the sheath material into the outer sheath is the conventional optical cable extrusion molding process.

[0032] As for the sheath material, the complete preparation process of the present invention should be as follows:

[0033] 1) Weigh the following raw materials in parts by weight: 100 parts by weight of rubber, 6-12 parts by weight of a mixture of carbon black and white carbon black, 1-3 parts by weight of calcium oxide, 1-5 parts by weight of an antioxidant, N-phenyl-α-aniline, 1-2 parts by weight of a dispersant, 2-5 parts by weight of a vulcanizing agent, 1-2 parts by weight of TMTD, 3-8 parts by weight of a plasticizer, and 0.3-0.6 parts by weight of sodium fatty acid;

[0034] After weighing the raw materials, first take the rubber and plasticize it at 50℃ until it is rolled, then cut it twice (120s / cut) and add antioxidant and dispersant;

[0035] 2) Calcium oxide is added and the mixing is continued. During the mixing process, after the 10th minute, the mixture of plasticizer, carbon black and white carbon black is added alternately in three equal amounts. The sodium fatty acid is added at the same time as the mixture of carbon black and white carbon black is added for the first time. After the addition is completed, the vulcanizing agent and accelerator are added after continuing to mix for 10 minutes. The rubber compound is obtained by mixing until the powder is completely eaten. The rubber compound is vulcanized at 150°C for 2 hours under a pressure of 20 MPa to complete the vulcanization treatment, and the sheath material is obtained by discharging the material.

[0036] The sheath material prepared by the above process has relatively good molding ability and is convenient for use in extrusion molding of optical cables to prepare outer sheath structures.

[0037] Specifically, the present invention specially adopts a mixture of rubber, calcium oxide, carbon black and white carbon black for use, the purpose of which is to enable the outer sheath to produce delayed hardening when the outer sheath is subjected to continuous shearing after the sheath material is extruded and molded. The delayed hardening can be described in a slightly vivid way, that is, if you cut meat with a knife but cut into the bone in the meat, the delayed hardening forms a hard contact. As described above, the blade is prone to curling, and the teeth of rodents are also prone to impact damage, which stimulates them to form a repelling effect.

[0038] The reason for this effect is that carbon black, white carbon black and calcium oxide are used in combination with rubber. Carbon black is a common filler used in rubber. It can form a filler network in rubber to reinforce the rubber material and increase the strength of the rubber material. However, under dynamic stress, the relative slip and friction between carbon black and carbon black, and between carbon black and rubber molecular chains will generate a certain amount of hysteresis heat. However, this hysteresis heat is not enough to stimulate and repel rodents. After the addition of white carbon black, both of them tend to form a network structure in the rubber, but using them at the same time will form mutual inhibition. Moreover, when white carbon black is subjected to stress in rubber, the slip and friction form of carbon black is different from that of carbon black. It uses rolling to form internal motion. Therefore, the different motion forms of the two will form a motion advantage and motion disadvantage according to the usage ratio when actually compounded and used, and then produce rapid enrichment in the local stress area, resulting in a certain degree of hardening with hysteresis, that is, hysteresis hardening. The calcium oxide uses industrial active calcium oxide, which increases the local expansion of the rubber after its addition, can improve the response efficiency of delayed hardening, and further enhance the anti-bite effect of the optical cable.

[0039] At the same time, carbon black, white carbon black and calcium oxide fillers can enhance the wear resistance of rubber, and also improve its direct ability to resist mechanical damage, such as friction resistance.

[0040] The beneficial effects of the present invention are:

[0041] The present invention adopts the combination of three types of fillers to enable the rubber outer sheath to produce a delayed hardening effect when used for optical cable anti-bite, thereby producing a good anti-bite effect while maintaining transportation convenience and providing good mechanical protection for the optical cable core. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below with reference to specific embodiments. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the embodiments of the present invention described below are generally only a portion of the embodiments of the present invention, rather than all of the embodiments. Therefore, all other embodiments derived by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0043] Unless otherwise specified, the raw materials used in the examples of the present invention are all commercially available or available to those skilled in the art; unless otherwise specified, the methods used in the examples of the present invention are all methods known to those skilled in the art.

[0044] Unless otherwise specified, the optical cable core of the present invention adopts a common three-core cable core as the experimental cable core.

[0045] Example 1

[0046] Preparation of sheath material:

[0047] 1) Weigh the following raw materials in parts by weight: 100 parts by weight of rubber, 9 parts by weight of a mixture of carbon black and white carbon black (carbon black content is 10 wt%), 2 parts by weight of calcium oxide, 3 parts by weight of an antioxidant, N-phenyl-α-aniline, 2 parts by weight of a dispersant, pentaerythritol tristearate, 3 parts by weight of a vulcanizing agent, 1 part by weight of TMTD, 5 parts by weight of a plasticizer, and 0.5 parts by weight of sodium fatty acid;

[0048] After weighing the raw materials, first take the rubber and plasticize it at 50℃ until it is rolled, then cut it twice (120s / cut) and add antioxidant and dispersant;

[0049] 2) Calcium oxide is added and the mixing is continued. During the mixing process, after the 10th minute, the mixture of plasticizer, carbon black and white carbon black is added alternately in three equal amounts. The sodium fatty acid is added at the same time as the mixture of carbon black and white carbon black is added for the first time. After the addition is completed, the vulcanizing agent and accelerator are added after continuing to mix for 10 minutes. The rubber compound is obtained by mixing until the powder is completely eaten. The rubber compound is vulcanized at 150°C for 2 hours under a pressure of 20 MPa to complete the vulcanization treatment, and the sheath material is obtained by discharging the material.

[0050] Example 2

[0051] Preparation of sheath material:

[0052] 1) Weigh the following raw materials in parts by weight: 100 parts by weight of rubber, 12 parts by weight of a mixture of carbon black and white carbon black (carbon black content is 5 wt%), 2 parts by weight of calcium oxide, 5 parts by weight of an antioxidant, N-phenyl-α-aniline, 1 part by weight of a dispersant, pentaerythritol tristearate, 5 parts by weight of a vulcanizing agent, 2 parts by weight of an accelerator, 3 parts by weight of a plasticizer, and 0.6 parts by weight of a sodium fatty acid;

[0053] After weighing the raw materials, first take the rubber and plasticize it at 50℃ until it is rolled, then cut it twice (120s / cut) and add antioxidant and dispersant;

[0054] 2) Calcium oxide is added and the mixing is continued. During the mixing process, after the 10th minute, the mixture of plasticizer, carbon black and white carbon black is added alternately in three equal amounts. The sodium fatty acid is added at the same time as the mixture of carbon black and white carbon black is added for the first time. After the addition is completed, the vulcanizing agent and accelerator are added after continuing to mix for 10 minutes. The rubber compound is obtained by mixing until the powder is completely eaten. The rubber compound is vulcanized at 150°C for 2 hours under a pressure of 20 MPa to complete the vulcanization treatment, and the sheath material is obtained by discharging the material.

[0055] Example 3

[0056] Preparation of sheath material:

[0057] 1) Weigh the following raw materials in parts by weight: 100 parts by weight of rubber, 6 parts by weight of a mixture of carbon black and white carbon black (carbon black content is 85 wt%), 3 parts by weight of calcium oxide, 2 parts by weight of an antioxidant, N-phenyl-α-aniline, 1.5 parts by weight of a dispersant, pentaerythritol tristearate, 3 parts by weight of a vulcanizing agent, 1 part by weight of TMTD, 3 parts by weight of a plasticizer, and 0.3 parts by weight of sodium fatty acid;

[0058] After weighing the raw materials, first take the rubber and plasticize it at 50℃ until it is rolled, then cut it twice (120s / cut) and add antioxidant and dispersant;

[0059] 2) Calcium oxide is added and the mixing is continued. During the mixing process, after the 10th minute, the mixture of plasticizer, carbon black and white carbon black is added alternately in three equal amounts. The sodium fatty acid is added at the same time as the mixture of carbon black and white carbon black is added for the first time. After the addition is completed, the vulcanizing agent and accelerator are added after continuing to mix for 10 minutes. The rubber compound is obtained by mixing until the powder is completely eaten. The rubber compound is vulcanized at 150°C for 2 hours under a pressure of 20 MPa to complete the vulcanization treatment, and the sheath material is obtained by discharging the material.

[0060] Example 4

[0061] Preparation of sheath material:

[0062] 1) Weigh the following raw materials in parts by weight: 100 parts by weight of rubber, 9 parts by weight of a mixture of carbon black and white carbon black (carbon black content is 90 wt%), 2 parts by weight of calcium oxide, 5 parts by weight of an antioxidant, N-phenyl-α-aniline, 2 parts by weight of a dispersant, pentaerythritol tristearate, 4 parts by weight of a vulcanizing agent, 1.5 parts by weight of an accelerator, 6 parts by weight of a plasticizer, and 0.6 parts by weight of a sodium fatty acid;

[0063] After weighing the raw materials, first take the rubber and plasticize it at 50℃ until it is rolled, then cut it twice (120s / cut) and add antioxidant and dispersant;

[0064] 2) Calcium oxide is added and the mixing is continued. During the mixing process, after the 10th minute, the mixture of plasticizer, carbon black and white carbon black is added alternately in three equal amounts. The sodium fatty acid is added at the same time as the mixture of carbon black and white carbon black is added for the first time. After the addition is completed, the vulcanizing agent and accelerator are added after continuing to mix for 10 minutes. The rubber compound is obtained by mixing until the powder is completely eaten. The rubber compound is vulcanized at 150°C for 2 hours under a pressure of 20 MPa to complete the vulcanization treatment, and the sheath material is obtained by discharging the material.

[0065] Comparative Example 1

[0066] Preparation of sheath material:

[0067] 1) Weigh the following raw materials in parts by weight: 100 parts by weight of rubber, 6 parts by weight of a mixture of carbon black and white carbon black (carbon black content is 10 wt%), 2 parts by weight of calcium oxide, 3 parts by weight of an antioxidant, N-phenyl-α-aniline, 2 parts by weight of a dispersant, pentaerythritol tristearate, 3 parts by weight of a vulcanizing agent, sulfur, 1 part by weight of an accelerator, 5 parts by weight of a plasticizer, and 0.5 parts by weight of a sodium fatty acid;

[0068] After weighing the raw materials, first take the rubber and plasticize it at 50℃ until it is rolled, then cut it twice (120s / cut) and add antioxidant and dispersant;

[0069] 2) Calcium oxide is added and the mixing is continued. During the mixing process, after the 10th minute, the mixture of plasticizer, carbon black and white carbon black is added alternately in three equal amounts. The sodium fatty acid is added at the same time as the mixture of carbon black and white carbon black is added for the first time. After the addition is completed, the vulcanizing agent and accelerator are added after continuing to mix for 10 minutes. The rubber compound is obtained by mixing until the powder is completely eaten. The rubber compound is vulcanized at 150°C for 2 hours under a pressure of 20 MPa to complete the vulcanization treatment, and the sheath material is obtained by discharging the material.

[0070] Comparative Example 2

[0071] Preparation of sheath material:

[0072] 1) Weigh the following raw materials in parts by weight: 100 parts by weight of rubber, 9 parts by weight of a mixture of carbon black and white carbon black (carbon black content is 85 wt%), 3 parts by weight of calcium oxide, 2 parts by weight of an antioxidant, N-phenyl-α-aniline, 1.5 parts by weight of a dispersant, pentaerythritol tristearate, 3 parts by weight of a vulcanizing agent, 1 part by weight of TMTD, 3 parts by weight of a plasticizer, and 0.3 parts by weight of sodium fatty acid;

[0073] After weighing the raw materials, first take the rubber and plasticize it at 50℃ until it is rolled, then cut it twice (120s / cut) and add antioxidant and dispersant;

[0074] 2) Calcium oxide is added and the mixing is continued. During the mixing process, after the 10th minute, the mixture of plasticizer, carbon black and white carbon black is added alternately in three equal amounts. The sodium fatty acid is added at the same time as the mixture of carbon black and white carbon black is added for the first time. After the addition is completed, the vulcanizing agent and accelerator are added after continuing to mix for 10 minutes. The rubber compound is obtained by mixing until the powder is completely eaten. The rubber compound is vulcanized at 150°C for 2 hours under a pressure of 20 MPa to complete the vulcanization treatment, and the sheath material is obtained by discharging the material.

[0075] Comparative Example 3

[0076] Preparation of sheath material:

[0077] 1) Weigh the following raw materials in parts by weight: 100 parts by weight of rubber, 9 parts by weight of a mixture of carbon black and white carbon black (carbon black content is 50 wt%), 3 parts by weight of calcium oxide, 2 parts by weight of an antioxidant, N-phenyl-α-aniline, 1.5 parts by weight of a dispersant, pentaerythritol tristearate, 3 parts by weight of a vulcanizing agent, 1 part by weight of TMTD, 3 parts by weight of a plasticizer, and 0.3 parts by weight of sodium fatty acid;

[0078] After weighing the raw materials, first take the rubber and plasticize it at 50℃ until it is rolled, then cut it twice (120s / cut) and add antioxidant and dispersant;

[0079] 2) Calcium oxide is added and the mixing is continued. During the mixing process, after the 10th minute, the mixture of plasticizer, carbon black and white carbon black is added alternately in three equal amounts. The sodium fatty acid is added at the same time as the mixture of carbon black and white carbon black is added for the first time. After the addition is completed, the vulcanizing agent and accelerator are added after continuing to mix for 10 minutes. The rubber compound is obtained by mixing until the powder is completely eaten. The rubber compound is vulcanized at 150°C for 2 hours under a pressure of 20 MPa to complete the vulcanization treatment, and the sheath material is obtained by discharging the material.

[0080] Specific application examples

[0081] The sheathing materials prepared in Examples 1-4 and Comparative Examples 1-3 were used to extrude optical cables. The cable cores used were semi-finished products from the factory, namely, commonly used three-core cables. After the sheathing materials were heated to a softened state, they were extruded onto the cable core surface using an optical cable extruder and cured to form experimental cables. Five experimental optical cables were prepared using the sheathing materials obtained in each example.

[0082] The experimental cables were subjected to a bite resistance test. Four fully transparent glass rooms with a size of 2m×2m×2m were set up for easy observation. Five test cables with a length of 1.5m were set up at a height of 0.35m. Eight male red-bellied squirrels with strong climbing and biting habits were placed in each fully transparent glass room. The selected red-bellied squirrels had basically the same physical signs and met the animal experiment standards. The test cables were observed and recorded continuously for 3 days. The total number of climbs, average duration of a single climb, average dwell time and number of bites of the test cables set up in each fully transparent glass room were recorded. The degree of damage to the test cables was determined by referring to the bite index in the article [Qin Ning. Research and Application of Rat-Proof Optical Cables [J]. China New Communications, 2012, 000(016): 54-55.]. The index was calculated as the average value of the five test cables in the same group.

[0083] The test results are shown in the following table.

[0084] Sheath material source Average damage index Day 1 Number of bites Day 3 Number of bites Example 1 0.31 63 53 Example 2 0.29 66 50 Example 3 0.36 62 52 Example 4 0.30 70 52 Comparative Example 1 1.21 61 58 Comparative Example 2 0.27 65 55 Comparative Example 3 3.87 66 68

[0085] As can be seen from the test results in the table above, the optical cable of the present invention, after using a specific sheathing material to prepare the outer sheath, has good anti-bite performance, and the average damage index of the optical cable is significantly reduced. By comparing Example 1 and Comparative Example 1, it can be found that when a mixture with a low carbon black content is used as a filler, its actual anti-bite performance has a large difference, mainly manifested in the relatively low hardness produced by delayed hardening, and the biting process can still easily cause damage to the optical cable. Comparing Comparative Example 2 with Example 3, it can be found that when a mixture with a high carbon black content is used as a filler, it still has good anti-bite performance after increasing the amount of the mixture. However, further observation and routine characterization found that the minimum bending radius of the optical cable made from the sheathing material of Example 3 is about 7 cm, while the minimum bending radius of Comparative Example 2 reaches about 11 cm. Since the cable cores used are the same, it can be expected that the reason for this difference is that the sheathing materials used for the outer sheath are different. Furthermore, a continuous measurement method was used to measure the maximum delayed hardening hardness of the optical cable outer sheath. The characterization results show that the maximum delayed hardening hardness of the optical cable made from the sheath material of Comparative Example 2 is approximately 28% higher than that of the optical cable made from the sheath material of Example 1. This shows that excessive addition of a carbon black / white carbon black mixture with a high carbon black content will also produce defects caused by a fully hardened structure. Therefore, to avoid this defect, the amount of mixtures with different carbon black contents should be controlled. In Comparative Example 3, however, the mixture used equal amounts of carbon black and white carbon black, and its anti-bite performance decreased dramatically, no longer having good anti-bite performance. Furthermore, manual tests showed that the delayed hardening phenomenon almost disappeared. This shows that delayed hardening is caused by the difference in the content of carbon black and white carbon black in the mixture.

Claims

1. An animal-resistant optical cable, comprising a cable core and a sheath material, characterized in that: The sheath material comprises the following components: 100 parts by weight of rubber, 6-12 parts by weight of a mixture of carbon black and white carbon black, 1-3 parts by weight of an oxide filler, 1-5 parts by weight of an antioxidant, 1-2 parts by weight of a dispersant, 2-5 parts by weight of a vulcanizing agent, 1-2 parts by weight of an accelerator, and 3-8 parts by weight of a plasticizer; The rubber is natural rubber and / or styrene-butadiene rubber and / or butadiene rubber; The mass percentage of carbon black in the mixture of carbon black and white carbon black is 5 to 10 wt% or 85 to 95 wt%; When the carbon black content is 5 to 10 wt%, the weight parts of the mixture used are 9 to 12 weight parts; When the carbon black content is 85-95 wt%, the weight parts of the mixture used are 6-9 weight parts; The oxide filler is calcium oxide.

2. The animal-resistant optical cable according to claim 1, characterized in that: The preparation method of the sheath material comprises: 1) The rubber is plasticized and rolled, then cut with a knife, and an antioxidant and dispersant are added; 2) Continue to mix and knead, first add oxide filler during the mixing process, then add plasticizer and the mixture of carbon black and white carbon black alternately, and finally add vulcanizing agent and accelerator. After the mixing is completed, vulcanize the material and obtain the anti-bite sheath material.

3. The animal-resistant optical cable according to claim 2, characterized in that: Step 1) The dispersant is triglyceride and / or pentaerythritol tristearate.

4. The animal-resistant optical cable according to claim 2, characterized in that: Step 2) The plasticizer and the mixture of carbon black and white carbon black are added at least three times, and the amount added each time does not exceed 45 wt% of the total amount added.

5. The animal-resistant optical cable according to claim 4, characterized in that: Fatty acid soap is added to the mixture of carbon black and white carbon black.