A Category 6 network cable for aviation

Abstract

The invention discloses a six-category network cable for aviation, which belongs to the field of cable technology, including a six-category network cable core, an insulating layer, a shielding layer and a sheath layer arranged in sequence from the core to the outer layer, and the sheath layer is made of a polyurethane elastomer material; the polyurethane elastomer material includes the following raw materials in parts by weight: 100 parts of polyurethane elastomer, 2-3 parts of hydrotalcite, 1.2-1.5 parts of lubricant, 3-4 parts of dispersant, and 2-3 parts of antioxidant. The six-category network cable of the present invention is made of a polyurethane elastomer material, and the polyurethane elastomer material includes a self-synthesized polyurethane elastomer and hydrotalcite, and the self-synthesized polyurethane elastomer uses a flame retardant chain extender as one of the chain extension components, which can give the polyurethane elastomer itself excellent and lasting flame retardant properties; in addition, the hydrotalcite and the flame retardant component can play a synergistic flame retardant effect, and improve the flame retardant and high temperature resistance of the sheath layer; therefore, the six-category network cable obtained by the present invention can be applied to the aviation field.

Description

Technical Field

[0001] The invention belongs to the technical field of cables, and in particular, relates to a Category 6 network cable for aviation. Background Art

[0002] Category 6 network cables refer to Category 6 cables, that is, cables that meet the CAT-6 standard. They have excellent transmission performance and transmission rate, and are increasingly widely used in aerospace and other fields. Currently, the types of related conductors and rubber materials used in aerospace cables are limited, and the space for product weight reduction is extremely limited. Weight reduction is of great significance to aerospace vehicles. Aircraft weight reduction means increasing carrying capacity, improving mechanical properties, increasing flight distance or range, and reducing fuel or propellant consumption.

[0003] Polyurethane elastomers have good mechanical properties, including tensile properties, tear properties, wear resistance, fatigue resistance, high toughness, high transparency, etc. They have good acid and alkali resistance, organic solvent resistance, surface finish, biocompatibility and a variety of processing and molding methods. At the same time, they have the advantage of light weight. Therefore, they are suitable for the production of Category 6 network cables in the aviation field. However, polyurethane elastomers are flammable substances, and a large number of molten droplets and obvious smoke particles are generated during the combustion process. Due to the special working environment of aviation (space environment), aviation cables are exposed to space rays for a long time, which can easily cause cable aging due to high temperature, and even cause cable combustion, posing a great safety hazard. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a Category 6 network cable for aviation.

[0005] The six categories of network cables of the present invention are made of polyurethane elastomer materials, and the polyurethane elastomer materials include self-synthesized polyurethane elastomer and hydrotalcite. The self-synthesized polyurethane elastomer uses a flame retardant chain extender as one of the chain extension components. The flame retardant chain extender can achieve flame retardant effects from multiple angles and mechanisms and has high-efficiency flame retardant characteristics. In addition, since the flame retardant component is located on the main chain of the polyurethane molecule, it is different from the added flame retardant component, and can give the polyurethane elastomer itself excellent and lasting flame retardant properties; in addition, the flame retardant components contained in the hydrotalcite and the polyurethane itself can also play a synergistic flame retardant effect, further improving the flame retardant and high temperature resistance of the sheath layer; therefore, the six categories of network cables obtained by the present invention can be suitable for the aviation field.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A six-category network cable for aviation, comprising a six-category network cable core, an insulation layer, a shielding layer and a sheath layer arranged in sequence from the core to the outer layer;

[0008] Wherein, the sheath layer is made of polyurethane elastomer material;

[0009] The polyurethane elastomer material comprises the following raw materials in parts by weight: 100 parts of polyurethane elastomer, 2-3 parts of hydrotalcite, 1.2-1.5 parts of lubricant, 3-4 parts of dispersant, and 2-3 parts of antioxidant;

[0010] The preparation method of the polyurethane elastomer material comprises the following steps:

[0011] The first step is to ultrasonically dissolve polycaprolactone diol, 4,4'-dicyclohexylmethane diisocyanate and DBTDL (dibutyltin dilaurate) in DMF, slowly heat the mixed solution to 70°C under magnetic stirring and N2 protection, then continuously stir at a constant temperature of 70°C for 8 hours, and cool to 30°C to obtain a prepolymer solution;

[0012] Step 2: Dissolve the flame retardant chain extender and chain extender E300 in an appropriate amount of DMF, then add to the prepolymer solution, stir continuously for 12 hours at 30°C under N2 protection, remove bubbles in vacuum, and dry at 70°C for 2 days to obtain a polyurethane elastomer;

[0013] The ratio of polycaprolactone diol (average molecular weight of about 2000), 4,4'-dicyclohexylmethane diisocyanate, DBTDL, DMF, flame retardant chain extender, and chain extender E300 is 2.5g: 0.98g: 0.05g: 10mL: 0.19g: 0.35g;

[0014] The third step is to mix the polyurethane elastomer, hydrotalcite, lubricant, dispersant and antioxidant according to the weight ratio and add them into the internal mixer for melt blending. The internal mixer is first operated at 10 rpm for 3-4 minutes to melt and fully disperse the materials. Then the speed is increased to 50-60 rpm, the temperature of each zone is set to 170-180°C, the internal mixer is kneaded for 10-12 minutes, and the material is discharged to obtain the polyurethane elastomer material.

[0015] The added hydrotalcite can increase the strength of the expanded carbon layer skeleton, promote further expansion of the carbon layer, and make the carbon layer stronger, thereby acting as an insulating barrier to prevent the exchange of heat and gas inside and outside, and reduce heat release and the release of CO and CO2; the flame retardant components contained in the hydrotalcite and polyurethane itself can also have a synergistic flame retardant effect, further improving the flame retardant and high temperature resistance of the sheath layer.

[0016] In addition, the chain extender E300 is also used in the synthesis process of polyurethane elastomer. This is a new type of polyurethane chain extender. Compared with MOCA, it is liquid at room temperature and has low viscosity, which is very helpful in reducing the viscosity of the system. It has a star-shaped molecular structure and forms a network structure during the cross-linking process, which makes the prepared elastomer have better toughness and elasticity and higher tensile strength.

[0017] Furthermore, the flame retardant chain extender is prepared by the following steps:

[0018] S1, phenyl dichlorophosphate and dichloromethane are placed in a three-necked flask, the temperature is maintained at 2-4 ° C, stirred to fully dissolve, and kept in a uniform stirring state, 3-bromopropionamide dispersion (controlling the dropping rate of 60 drops / second) is dripped into the three-necked flask using a constant pressure separatory funnel, during the process, the pH value of the reaction system is adjusted to remain at 6-7, and the reaction is carried out for 2h after the dropwise addition is completed, and dichloromethane is removed by rotary evaporation, and then recrystallized and dried at room temperature to obtain an intermediate; the ratio of the amount of phenyl dichlorophosphate, dichloromethane, and 3-bromopropionamide dispersion is 0.1mol:100mL:100mL; 3-bromopropionamide dispersion includes 3-bromopropionamide, potassium carbonate and dichloromethane, and the ratio of the three is 0.22mol:13.8g:100mL;

[0019] Under the action of potassium carbonate, -Cl on the phenyl dichlorophosphate molecule reacts with -NH2 on the 3-bromopropionamide molecule to obtain an intermediate. The reaction process is as follows:

[0020]

[0021] S2. Add bisphenol-S and acetone to a three-necked flask, stir at room temperature until completely dissolved, then add K2CO3 powder, heat and reflux for 4 hours under N2 atmosphere, dissolve the intermediate in an appropriate amount of acetone, then uniformly add the solution dropwise to the three-necked flask, after the addition is completed, continue to react for 6 hours at a constant temperature of 56°C, then pour the reactant into deionized water to precipitate the product, finally wash it with deionized water and acetone for 3 times respectively, and then place the product in a vacuum oven at 80°C and dry it for 12 hours to obtain a flame retardant chain extender; the ratio of bisphenol-S, acetone, K2CO3, and intermediate is 12.5g:100mL:2.76g:8.84g;

[0022] Under the action of potassium carbonate, -Br on the intermediate molecule reacts chemically with the phenolic hydroxyl group on the bisphenol-S molecule to obtain a flame retardant chain extender. The specific reaction process is as follows:

[0023]

[0024] The obtained flame retardant chain extender contains -OH at both ends, and can participate in the synthesis process of polyurethane elastomer as a chain extender, and graft the organic molecular chain on the main chain of polyurethane elastomer molecule; it should be further explained that the organic molecular chain contains benzene ring, nitrogen-containing group, phosphate group and -SO2- group, the benzene ring has a good carbon-forming effect, the nitrogen-containing group releases ammonia, nitrogen, deep nitrogen oxides and other non-flammable gases when heated, the phosphate group forms a gas phase product PO· when burned, which can capture H· and HO· in the flame and interrupt the chain reaction of combustion, and the -SO2- structure undergoes thermal decomposition to release sulfur oxides such as SO2, which can promote Fries rearrangement and cross-linking to form carbon. Therefore, these groups have a synergistic effect, so that the organic molecular chain can achieve flame retardant effect from multiple angles and mechanisms, and has high-efficiency flame retardant characteristics. In addition, because the flame retardant component is located on the main chain of the polyurethane molecule, unlike the added flame retardant component, it can give the polyurethane elastomer itself excellent and lasting flame retardant properties.

[0025] Beneficial effects of the present invention:

[0026] The six categories of network cables of the present invention are made of polyurethane elastomer materials, and the polyurethane elastomer materials include self-synthesized polyurethane elastomer and hydrotalcite. The self-synthesized polyurethane elastomer uses a flame retardant chain extender as one of the chain extension components. The flame retardant chain extender can achieve flame retardant effects from multiple angles and mechanisms and has high-efficiency flame retardant characteristics. In addition, since the flame retardant component is located on the main chain of the polyurethane molecule, it is different from the added flame retardant component, and can give the polyurethane elastomer itself excellent and lasting flame retardant properties; in addition, the flame retardant components contained in the hydrotalcite and the polyurethane itself can also play a synergistic flame retardant effect, further improving the flame retardant and high temperature resistance of the sheath layer; therefore, the six categories of network cables obtained by the present invention can be suitable for the aviation field. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1

[0029] Preparation of flame retardant chain extender:

[0030] S1, 0.1mol phenyl dichlorophosphate and 100mL dichloromethane are placed in a three-necked flask, the temperature is maintained at 2-4°C, stirred to fully dissolve, and kept in a uniform stirring state, 100mL of 3-bromopropionamide dispersion (controlling the dropping rate to 60 drops / second) is dripped into the three-necked flask using a constant pressure separatory funnel, during the process, the pH value of the reaction system is adjusted to be maintained at 6-7, and the reaction is carried out for 2h after the dropwise addition is completed, and the dichloromethane is removed by rotary evaporation, and then recrystallized and dried at room temperature to obtain an intermediate; the 3-bromopropionamide dispersion includes 0.22mol of 3-bromopropionamide, 13.8g of potassium carbonate and 100mL of dichloromethane;

[0031] S2. Add 12.5g of bisphenol-S and 100mL of acetone to a three-necked flask, stir at room temperature until completely dissolved, then add 2.76g of K2CO3 powder, heat and reflux for 4h under N2 atmosphere, dissolve 8.84g of the intermediate in 50mL of acetone, then add the solution dropwise to the three-necked flask at a uniform rate, after the addition is completed, continue the reaction at a constant temperature of 56°C for 6h, then pour the reactant into 300mL of deionized water to precipitate the product, finally wash it with deionized water and acetone for 3 times respectively, and then place the product in a vacuum oven at 80°C and dry it for 12h to obtain a flame retardant chain extender.

[0032] Example 2

[0033] Preparation of flame retardant chain extender:

[0034] S1, 0.2mol phenyl dichlorophosphate and 200mL dichloromethane are placed in a three-necked flask, the temperature is maintained at 2-4°C, stirred to fully dissolve, and kept in a uniform stirring state, 200mL of 3-bromopropionamide dispersion (controlling the dropping rate to 60 drops / second) is dripped into the three-necked flask using a constant pressure separatory funnel, during the process, the pH value of the reaction system is adjusted to be maintained at 6-7, and the reaction is carried out for 2h after the dropwise addition is completed, and after the dichloromethane is removed by rotary evaporation, recrystallization is carried out and drying is carried out at room temperature to obtain an intermediate; the 3-bromopropionamide dispersion includes 0.44mol of 3-bromopropionamide, 27.6g of potassium carbonate and 200mL of dichloromethane;

[0035] S2. Add 25g of bisphenol-S and 200mL of acetone to a three-necked flask, stir at room temperature until completely dissolved, then add 5.52g of K2CO3 powder, heat and reflux for 4h under N2 atmosphere, dissolve 17.68g of the intermediate in 100mL of acetone, then add the solution dropwise to the three-necked flask at a uniform rate, after the addition is completed, continue the reaction at a constant temperature of 56°C for 6h, then pour the reactant into 600mL of deionized water to precipitate the product, finally wash it with deionized water and acetone for 3 times respectively, and then place the product in a vacuum oven at 80°C and dry it for 12h to obtain a flame retardant chain extender.

[0036] Example 3

[0037] Preparation of polyurethane elastomer material:

[0038] The first step is to ultrasonically dissolve 100 g of polycaprolactone diol, 39.2 g of 4,4'-dicyclohexylmethane diisocyanate and DBTDL in 400 mL of DMF, slowly heat the mixed solution to 70°C under magnetic stirring and N2 protection, then continuously stir at a constant temperature of 70°C for 8 hours, and cool to 30°C to obtain a prepolymer solution;

[0039] Step 2: 7.6 g of the flame retardant chain extender prepared in Example 1 and 14 g of the chain extender E300 were dissolved in 240 mL of DMF, and then added to the prepolymer solution, stirred continuously for 12 h at 30 ° C. under N2 protection, vacuum defoamed, and dried at 70 ° C. for 2 days to obtain a polyurethane elastomer;

[0040] The third step is to mix 100g of polyurethane elastomer, 2g of hydrotalcite, 1.2g of lubricant, 3g of dispersant and 2g of antioxidant into an internal mixer for melt blending. The internal mixer is first run at 10rpm for 3min to allow the materials to melt and disperse fully, then the speed is increased to 50rpm, the temperature of each zone is set to 170°C, the internal mixer is kneaded for 10min, and the material is discharged to obtain the polyurethane elastomer material.

[0041] Example 4

[0042] Preparation of polyurethane elastomer material:

[0043] The first step is to ultrasonically dissolve 100 g of polycaprolactone diol, 39.2 g of 4,4'-dicyclohexylmethane diisocyanate and DBTDL in 400 mL of DMF, slowly heat the mixed solution to 70°C under magnetic stirring and N2 protection, then continuously stir at a constant temperature of 70°C for 8 hours, and cool to 30°C to obtain a prepolymer solution;

[0044] Step 2: 7.6 g of the flame retardant chain extender prepared in Example 2 and 14 g of the chain extender E300 were dissolved in 240 mL of DMF, and then added to the prepolymer solution, stirred continuously for 12 h at 30 ° C. under N2 protection, vacuum defoamed, and dried at 70 ° C. for 2 days to obtain a polyurethane elastomer;

[0045] The third step is to mix 100 g of polyurethane elastomer, 2.5 g of hydrotalcite, 1.35 g of lubricant, 3.5 g of dispersant and 2.5 g of antioxidant into an internal mixer for melt blending. The internal mixer is first run at 10 rpm for 3.5 min to allow the materials to melt and disperse fully. Then the speed is increased to 55 rpm, the temperature of each zone is set to 175°C, the internal mixer is kneaded for 11 min, and the material is discharged to obtain a polyurethane elastomer material.

[0046] Example 5

[0047] Preparation of polyurethane elastomer material:

[0048] The first step is to ultrasonically dissolve 100 g of polycaprolactone diol, 39.2 g of 4,4'-dicyclohexylmethane diisocyanate and DBTDL in 400 mL of DMF, slowly heat the mixed solution to 70°C under magnetic stirring and N2 protection, then continuously stir at a constant temperature of 70°C for 8 hours, and cool to 30°C to obtain a prepolymer solution;

[0049] Step 2: 7.6 g of the flame retardant chain extender prepared in Example 1 and 14 g of the chain extender E300 were dissolved in 240 mL of DMF, and then added to the prepolymer solution, stirred continuously for 12 h at 30 ° C. under N2 protection, vacuum defoamed, and dried at 70 ° C. for 2 days to obtain a polyurethane elastomer;

[0050] The third step is to mix 100g of polyurethane elastomer, 3g of hydrotalcite, 1.5g of lubricant, 4g of dispersant and 3g of antioxidant into an internal mixer for melt blending. The internal mixer is first run at 10rpm for 4min to allow the materials to melt and disperse fully, then the speed is increased to 60rpm, the temperature of each zone is set to 180°C, the internal mixer is kneaded for 12min, and the material is discharged to obtain the polyurethane elastomer material.

[0051] Comparative Example

[0052] Ordinary polyurethane elastomer.

[0053] The polyurethane elastomer materials obtained in Examples 3-5 and Comparative Examples were processed into standard test samples and subjected to the following performance tests:

[0054] The test characterization was carried out using an electronic universal testing machine of model E44 (dumbbell-shaped standard specimen with a length of 50 mm, tensile test was carried out at 200 mm / min);

[0055] The oxygen index LOI of the material was tested using a digital oxygen index meter model 5801 (sample size 100x6.5x3mm 3 );

[0056] The UL-94 vertical burning rating was tested using a CZF-6 horizontal vertical burning tester (sample size: 100x13x3mm 3 );

[0057] The measured results are shown in the following table:

[0058]

[0059]

[0060] It can be seen from the data in the above table that the polyurethane elastomer synthesized in the present invention has higher mechanical properties and excellent flame retardant properties.

[0061] Example 6

[0062] A Category 6 network cable for aviation includes a Category 6 network cable core, an insulation layer, a shielding layer and a sheath layer which are sequentially arranged from the core to the outer layer, and the sheath layer is made of the polyurethane elastomer material prepared in Example 4-5.

[0063] After testing, the six-category network cable for aviation obtained by the present invention meets various requirements of the national military standard GJB773A-2000.

[0064] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0065] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A Category 6 network cable for aviation, comprising a Category 6 network cable core, an insulation layer, a shielding layer and a sheath layer arranged in sequence from the core to the outer layer, characterized in that: The sheath layer is made of polyurethane elastomer material; The polyurethane elastomer material comprises the following raw materials in parts by weight: 100 parts of polyurethane elastomer, 2-3 parts of hydrotalcite, 1.2-1.5 parts of lubricant, 3-4 parts of dispersant, and 2-3 parts of antioxidant; The preparation method of the polyurethane elastomer material comprises the following steps: The first step is to ultrasonically dissolve polycaprolactone diol, 4,4'-dicyclohexylmethane diisocyanate and DBTDL in DMF, slowly heat the mixed solution to 70°C under magnetic stirring and N2 protection, then continuously stir at a constant temperature of 70°C for 8 hours, and cool to 30°C to obtain a prepolymer solution; Step 2: Dissolve the flame retardant chain extender and chain extender E300 in an appropriate amount of DMF, then add to the prepolymer solution, stir continuously for 12 hours at 30°C under N2 protection, remove bubbles in vacuum, and dry at 70°C for 2 days to obtain a polyurethane elastomer; Step 3: Mix the polyurethane elastomer, hydrotalcite, lubricant, dispersant and antioxidant according to weight ratio and add them into an internal mixer for melt blending. The internal mixer is first operated at 10 rpm for 3-4 min to melt and fully disperse the materials. Then the speed is increased to 50-60 rpm, the temperature of each zone is set to 170-180° C., and the materials are mixed for 10-12 min. The materials are discharged to obtain a polyurethane elastomer material. Wherein, the flame retardant chain extender is prepared by the following steps: S1. Phenyl dichlorophosphate and dichloromethane are placed in a three-necked flask, the temperature of which is maintained at 2-4°C, stirred to fully dissolve, and the stirring is maintained at a uniform speed. The 3-bromopropionamide dispersion is dripped into the three-necked flask using a constant pressure separatory funnel. During the process, the pH value of the reaction system is adjusted to be maintained at 6-7. After the dropwise addition is completed, the reaction is carried out for 2 hours, and the dichloromethane is removed by rotary evaporation, followed by recrystallization and drying at room temperature to obtain an intermediate; S2. Add bisphenol-S and acetone to a three-necked flask, stir at room temperature until completely dissolved, then add K2CO3 powder, heat and reflux for 4 hours under N2 atmosphere, dissolve the intermediate in an appropriate amount of acetone, then uniformly add the solution dropwise to the three-necked flask, after the addition is completed, continue to react at a constant temperature of 56°C for 6 hours, then pour the reactants into deionized water to precipitate the products, finally wash with deionized water and acetone for 3 times respectively, and then place the product in a vacuum oven at 80°C and dry for 12 hours to obtain a flame retardant chain extender.

2. The aviation category 6 network cable according to claim 1, characterized in that: The usage ratio of polycaprolactone diol, 4,4'-dicyclohexylmethane diisocyanate, DBTDL, DMF, flame retardant chain extender and chain extender E300 is 2.5g:0.98g:0.05g:10mL:0.19g:0.35g.

3. The aviation category 6 network cable according to claim 1, characterized in that: In step S1, the ratio of the amount of phenyl dichlorophosphate, dichloromethane, and 3-bromopropionamide dispersion is 0.1 mol:100 mL:100 mL; the 3-bromopropionamide dispersion includes 3-bromopropionamide, potassium carbonate and dichloromethane, and the ratio of the three is 0.22 mol:13.8 g:100 mL.

4. The aviation category 6 network cable according to claim 1, characterized in that: In step S2, the ratio of bisphenol-S, acetone, K2CO3 and intermediate is 12.5g:100mL:2.76g:8.84g.

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