Anti-kink robotic cable

Abstract

This invention discloses an anti-torsion robot cable, belonging to the field of cable technology. It comprises, from the inside out, a cable core, an insulation layer, and an outer sheath layer. The outer sheath layer is made of the following materials in parts by weight: 80-100 parts polyvinyl chloride, 20-25 parts multifunctional additives, 2-3 parts calcium / zinc composite stabilizer, 1-2 parts lubricant, and 0.5-0.8 parts antioxidant. The anti-torsion robot cable provided by this invention incorporates multifunctional additives in its outer sheath layer, based on the molecular design principle of phosphorus-nitrogen synergistic flame retardancy and lactic acid ester group high-efficiency plasticization, which can significantly improve the overall performance of the cable from multiple dimensions.

Description

Technical Field

[0001] This invention belongs to the field of cable technology, specifically, it relates to an anti-torsion robot cable. Background Technology

[0002] Currently, with the rapid development of industrial robot technology, the performance requirements for its supporting cables are increasingly stringent. Robot cables frequently withstand dynamic stresses such as reciprocating torsion and bending during actual use, thus requiring the outer sheath material to possess excellent flexibility, fatigue resistance, flame retardancy, and low smoke and toxicity. In existing technologies, polyvinyl chloride (PVC) is widely used for cable sheaths due to its good processing performance and cost advantages. However, traditional PVC materials themselves have poor flexibility and are prone to cracking or torsional failure under repeated torsion conditions. To improve flexibility, small-molecule plasticizers (such as phthalates and citrates) are often added to PVC. However, these plasticizers are prone to migration and volatilization during long-term use, leading to material performance degradation. Simultaneously, common plasticizers are often flammable, significantly reducing the flame retardant properties of the material. To meet flame retardant requirements, existing technologies typically require the addition of halogenated or phosphorus-based flame retardants. However, the addition of flame retardants often degrades the mechanical properties and flexibility of the material, making the cable more prone to cracking during dynamic torsion. Furthermore, some flame retardants produce large amounts of smoke and toxic gases when burning, which does not meet environmental and safety requirements.

[0003] Therefore, existing robot cable sheath materials cannot simultaneously achieve high torsional durability, excellent flexibility, efficient flame retardancy and smoke suppression performance, and long-term stability. There is an urgent need to develop a cable structure and sheath material that can comprehensively solve the above problems. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an anti-torsion robot cable.

[0005] The objective of this invention can be achieved through the following technical solutions: An anti-torsion robot cable comprises, from the inside out, a cable core, an insulation layer, and an outer sheath layer; wherein, the material of the outer sheath layer comprises the following parts by weight: 80-100 parts polyvinyl chloride, 20-25 parts multifunctional additive, 2-3 parts calcium / zinc composite stabilizer, 1-2 parts lubricant, and 0.5-0.8 parts antioxidant.

[0006] In a more optimized manner, the preparation process of the multifunctional additive is as follows: A1: Mix N-acetyl-L-alanine, L-lactic acid, and p-toluenesulfonic acid, stir until homogeneous, heat to 120℃, stir under normal pressure for 1-2 hours, then continue to heat to 150℃ and maintain the temperature for 6-7 hours. After the reaction is complete, stop heating, cool to 80℃, adjust the pH to 5-6 with dilute NaHCO3 solution, distill under reduced pressure for 1-2 hours, and filter under reduced pressure while hot to obtain intermediate A. A2: Under a protective atmosphere, intermediate A was added to chloroform and stirred evenly at room temperature. Then, thionyl chloride was slowly added dropwise. After the addition was complete, the temperature was raised to 65°C and the reaction was carried out for 4-5 hours. After the reaction was completed, the solvent and excess thionyl chloride were removed by rotary evaporation to obtain intermediate B. A3: Dissolve 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide and triethylamine in chloroform and stir until homogeneous to obtain solution A; dissolve intermediate B in chloroform and stir until homogeneous to obtain solution B; under a protective atmosphere, slowly add solution B dropwise to solution A. After the addition is complete, raise the temperature to 70℃ and react for 20-24 hours. After the reaction is complete, wash three times with deionized water to remove triethylamine hydrochloride and unreacted raw materials. Dry the organic phase with anhydrous magnesium sulfate, remove the solvent by rotary evaporation, and dry to obtain a multifunctional additive.

[0007] In this scheme, N-acetyl-L-alanine and L-lactic acid are first melt-polymerized at high temperature under the action of acidic catalyst p-toluenesulfonic acid to form a carboxyl-containing prepolymer intermediate A. Subsequently, the carboxyl group on intermediate A undergoes an acyl chloride reaction under the action of thionyl chloride to transform it into an acyl chloride intermediate B with higher reactivity. Finally, in the presence of the acid-binding agent triethylamine, the acyl chloride group of intermediate B undergoes an esterification reaction with the phenolic hydroxyl group on 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide=, introducing the phosphorus-containing phenanthrene ring structure into the molecular chain, and finally obtaining a multifunctional additive.

[0008] The structure of the multifunctional additive is shown below: In a more optimized manner, the raw materials for preparing intermediate A include the following components: by weight, 130-140 parts of N-acetyl-L-alanine, 95-98 parts of L-lactic acid, and 2-3 parts of p-toluenesulfonic acid.

[0009] In a more optimized manner, the raw materials for preparing intermediate B include the following components: by weight, 10-12 parts intermediate A, 50-60 parts chloroform, and 6-8 parts thionyl chloride.

[0010] More preferably, the raw materials for preparing solution A include the following components: by weight, 3-5 parts of 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, 1-2 parts of triethylamine, and 80-100 parts of chloroform; the raw materials for preparing solution B include the following components: by weight, 4-5 parts of intermediate B and 60-80 parts of chloroform.

[0011] More preferably, the lubricant includes one or more of stearic acid and polyethylene wax.

[0012] More preferably, the antioxidant includes one or more of antioxidant 168 and antioxidant 2246.

[0013] The beneficial effects of this invention are: This invention provides an anti-torsion robotic cable, in which a multifunctional additive introduced into the outer sheath layer, based on the molecular design principle of phosphorus-nitrogen synergistic flame retardancy and lactic acid ester group high-efficiency plasticization, can significantly improve the overall performance of the cable from multiple dimensions. First, the phosphorus-nitrogen flame retardant units contained in the additive molecule can promote the rapid formation of a dense carbon layer in the condensed phase when the cable is exposed to high temperatures or combustion, effectively isolating oxygen and heat transfer. Simultaneously, it captures free radicals in the gas phase, terminates the combustion chain reaction, and inhibits the generation and release of smoke, thereby endowing the cable with excellent flame retardant, smoke-suppressing, and low-toxicity properties, overcoming the defects of traditional plasticizers that are flammable and produce excessive smoke. Second, the lactic acid ester plasticizing units in the additive can effectively weaken the secondary valence bonds between polyvinyl chloride molecular chains, lower the glass transition temperature of the material, and significantly improve the flexibility and processing fluidity of the outer sheath layer. This allows the cable to maintain stable mechanical properties and fatigue resistance under dynamic conditions such as repeated torsion and bending, while avoiding the damage to the mechanical properties of the material caused by conventional flame retardants. In addition, this multifunctional additive has a large molecular structure and polar groups, and its migration rate in polyvinyl chloride matrix is ​​extremely low, which significantly reduces the volatilization and leakage of plasticizers and flame retardant components, ensuring the long-term stability of cable performance during long-term use. Detailed Implementation

[0014] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0015] Example 1: A manufacturing process for an anti-torsion robot cable, comprising the following steps: Copper-tin alloy wires are twisted together to form a conductor to obtain the cable core. After being placed in parallel, styrene-butadiene rubber is extruded over the core to form an insulation layer. Then, an outer sheath material is extruded and coated onto the surface of the insulation layer to form the outer sheath. The outer sheath material includes the following materials by weight: 80 parts polyvinyl chloride, 20 parts multifunctional additive, 2 parts calcium / zinc composite stabilizer, 1 part lubricant (polyethylene wax), and 0.5 parts antioxidant (antioxidant 168). The preparation process of the multifunctional additive is as follows: A1: Mix 130 parts of N-acetyl-L-alanine, 95 parts of L-lactic acid, and 2 parts of p-toluenesulfonic acid, stir evenly, heat to 120℃, stir under normal pressure for 1 hour, then continue to heat to 150℃ and keep the reaction at this temperature for 6 hours. After the reaction is completed, stop heating, cool to 80℃, adjust the pH to 5 with dilute NaHCO3 solution, distill under reduced pressure for 1 hour, and filter under reduced pressure while hot to obtain intermediate A. A2: Under a protective atmosphere, 10 parts of intermediate A were added to 50 parts of chloroform and stirred evenly at room temperature. 6 parts of thionyl chloride were slowly added dropwise. After the addition was complete, the temperature was raised to 65°C and the reaction was carried out for 4 hours. After the reaction was completed, the solvent and excess thionyl chloride were removed by rotary evaporation to obtain intermediate B. A3: Dissolve 3 parts of 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide and 1 part of triethylamine in 80 parts of chloroform and stir until homogeneous to obtain solution A; dissolve 4 parts of intermediate B in 60 parts of chloroform and stir until homogeneous to obtain solution B; under a protective atmosphere, slowly add solution B dropwise to solution A. After the addition is complete, raise the temperature to 70°C and react for 20 hours. After the reaction is complete, wash 3 times with deionized water to remove triethylamine hydrochloride and unreacted raw materials. Dry the organic phase with anhydrous magnesium sulfate, remove the solvent by rotary evaporation, and dry to obtain a multifunctional additive.

[0016] Example 2: A manufacturing process for an anti-torsion robot cable, comprising the following steps: Copper-tin alloy wires are twisted together to form a conductor to obtain the cable core. After being placed in parallel, styrene-butadiene rubber is extruded over the core to form an insulation layer. Then, an outer sheath material is extruded and coated onto the surface of the insulation layer to form the outer sheath. The outer sheath material includes the following parts by weight: 100 parts polyvinyl chloride, 25 parts multifunctional additive, 3 parts calcium / zinc composite stabilizer, 2 parts lubricant (polyethylene wax), and 0.8 parts antioxidant (antioxidant 168). The preparation process of the multifunctional additive is as follows: A1: Mix 140 parts of N-acetyl-L-alanine, 98 parts of L-lactic acid, and 3 parts of p-toluenesulfonic acid, stir evenly, heat to 120℃, stir under normal pressure for 2 hours, then continue to heat to 150℃ and keep the reaction at this temperature for 7 hours. After the reaction is completed, stop heating, cool to 80℃, adjust the pH to 6 with dilute NaHCO3 solution, distill under reduced pressure for 2 hours, and filter under reduced pressure while hot to obtain intermediate A. A2: Under a protective atmosphere, 12 parts of intermediate A were added to 60 parts of chloroform and stirred evenly at room temperature. 8 parts of thionyl chloride were slowly added dropwise. After the addition was complete, the temperature was raised to 65°C and the reaction was carried out for 5 hours. After the reaction was completed, the solvent and excess thionyl chloride were removed by rotary evaporation to obtain intermediate B. A3: Dissolve 5 parts of 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide and 2 parts of triethylamine in 100 parts of chloroform and stir until homogeneous to obtain solution A; dissolve 5 parts of intermediate B in 80 parts of chloroform and stir until homogeneous to obtain solution B; under a protective atmosphere, slowly add solution B dropwise to solution A. After the addition is complete, raise the temperature to 70°C and react for 24 hours. After the reaction is complete, wash three times with deionized water to remove triethylamine hydrochloride and unreacted raw materials. Dry the organic phase with anhydrous magnesium sulfate, remove the solvent by rotary evaporation, and dry to obtain a multifunctional additive.

[0017] Example 3: A manufacturing process for an anti-torsion robot cable, comprising the following steps: Copper-tin alloy wires are twisted together to form a conductor to obtain the cable core. After being placed in parallel, styrene-butadiene rubber is extruded over the core to form an insulation layer. Then, an outer sheath material is extruded and coated onto the surface of the insulation layer to form the outer sheath. The outer sheath material includes the following parts by weight: 90 parts polyvinyl chloride, 22.5 parts multifunctional additive, 2.5 parts calcium / zinc composite stabilizer, 1.5 parts lubricant (polyethylene wax), and 0.65 parts antioxidant (antioxidant 168). The preparation process of the multifunctional additive is as follows: A1: Mix 135 parts of N-acetyl-L-alanine, 96.5 parts of L-lactic acid, and 2.5 parts of p-toluenesulfonic acid, stir evenly, heat to 120℃, stir under normal pressure for 1.5h, then continue to heat to 150℃, keep the temperature for 6.5h, after the reaction is completed, stop heating, cool to 80℃, adjust pH to 5.5 with dilute NaHCO3 solution, distill under reduced pressure for 1.5h, filter under reduced pressure while hot to obtain intermediate A; A2: Under a protective atmosphere, 11 parts of intermediate A were added to 55 parts of chloroform and stirred evenly at room temperature. 7 parts of thionyl chloride were slowly added dropwise. After the addition was complete, the temperature was raised to 65°C and the reaction was carried out for 4.5 h. After the reaction was completed, the solvent and excess thionyl chloride were removed by rotary evaporation to obtain intermediate B. A3: Dissolve 4 parts of 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide and 1.5 parts of triethylamine in 90 parts of chloroform and stir until homogeneous to obtain solution A; dissolve 4.5 parts of intermediate B in 70 parts of chloroform and stir until homogeneous to obtain solution B; under a protective atmosphere, slowly add solution B dropwise to solution A. After the addition is complete, raise the temperature to 70℃ and react for 22 hours. After the reaction is complete, wash three times with deionized water to remove triethylamine hydrochloride and unreacted raw materials. Dry the organic phase with anhydrous magnesium sulfate, remove the solvent by rotary evaporation, and dry to obtain a multifunctional additive.

[0018] Comparative Example 1: Using a commercially available plasticizer to replace the multifunctional additive (acetylated tributyl citrate), as detailed below: Copper-tin alloy wires are twisted together to form a conductor to obtain the cable core. After being placed in parallel, styrene-butadiene rubber is extruded over the core to form an insulation layer. Then, an outer sheath material is extruded and coated on the surface of the insulation layer to form the outer sheath. The outer sheath material includes the following parts by weight: 90 parts polyvinyl chloride, 22.5 parts tributyl acetylacetonate, 2.5 parts calcium / zinc composite stabilizer, 1.5 parts lubricant (polyethylene wax), and 0.65 parts antioxidant (antioxidant 168).

[0019] Comparative Example 2: No multifunctional additives were added, as detailed below: Copper-tin alloy wires are twisted together to form a conductor to obtain the cable core. After being placed in parallel, styrene-butadiene rubber is extruded over the core to form an insulation layer. Then, an outer sheath material is extruded and coated on the surface of the insulation layer to form the outer sheath. The outer sheath material includes the following materials by weight: 90 parts polyvinyl chloride, 2.5 parts calcium / zinc composite stabilizer, 1.5 parts lubricant (polyethylene wax), and 0.65 parts antioxidant (antioxidant 168).

[0020] Testing experiment: (1) The cables of the examples and comparative examples were subjected to torsion tests at room temperature. The test method was in accordance with Appendix B of TICW / 01-2009. A total of 10,000 torsion tests were conducted. After the test, the pass rate was evaluated. The evaluation criteria were: no cracks or twisting phenomena on the surface of the sample. (2) The tensile strength and elongation at break of the outer sheath of the cables in the examples and comparative examples were tested in accordance with the standard GB / T 1040.1-2025 "Determination of tensile properties of plastics - Part 1: General". (3) The outer sheath of the cables in the examples and comparative examples was subjected to a high-temperature test in accordance with the standard GB / T 2406.3-2022 "Determination of Combustion Behavior by Oxygen Index Method for Plastics - Part 3: High Temperature Test" to determine its oxygen index; (4) The smoke suppression performance of the cable outer sheath of the examples and comparative examples was tested according to standard ISO 5660-1; wherein the sample size of the cable outer sheath was 100mm×100mm×3mm and the radiation power was 35kW / m. 2 ; The obtained data is shown in the table below: Conclusion: A comparison of the test data from the above embodiments and comparative examples shows that the anti-torsion robot cable provided by this invention significantly improves its overall performance by introducing a multifunctional additive with a specific structure into the outer sheath. Specifically, the cables of Embodiments 1 to 3 showed no surface cracks or twisting after 10,000 cycles of room temperature torsion testing, while Comparative Example 1 (using a commercially available plasticizer) and Comparative Example 2 (without the multifunctional additive) failed the test. This indicates that the additive effectively enhances the cable's flexibility and fatigue resistance, enabling it to adapt to dynamic working conditions such as repeated torsion and bending. Regarding mechanical properties, the tensile strength (17.6-25.7 MPa) of the embodiments falls between the two comparative examples, but the elongation at break (525.5%-545.8%) is significantly higher than that of Comparative Example 1 (398.7%) and Comparative Example 2 (15.8%). This demonstrates that the multifunctional additive significantly improves the material's ductility while maintaining sufficient strength, avoiding the damage to flexibility caused by conventional flame retardants or plasticizers. In terms of flame retardancy and smoke suppression performance, the limiting oxygen index of the embodiments (32.6%-36.8%) was significantly better than that of Comparative Example 1 (21.5%), although lower than that of Comparative Example 2 (42.5%) which did not contain flame retardant components. However, the latter had extremely low elongation at break and failed the torsion test, indicating that the embodiments achieved a good balance between flame retardancy and mechanical flexibility. At the same time, the total smoke production of the embodiments (16.5-19.8m³) was also lower. 2 It is far lower than the two comparative examples (33.1m respectively). 2 and 28.5m 2 This demonstrates that the multifunctional additive can effectively suppress smoke release, giving the cable low smoke and low toxicity. In summary, the anti-torsion robot cable of this invention not only possesses excellent torsional durability and flexibility, but also exhibits good flame retardant and smoke-suppressing properties, with overall performance significantly superior to existing technical solutions.

[0021] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0022] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A torsion-resistant robot cable, characterized in that, From the inside out, it includes the cable core, insulation layer and outer sheath layer; the outer sheath layer is made of the following materials in parts by weight: 80-100 parts polyvinyl chloride, 20-25 parts multifunctional additive, 2-3 parts calcium / zinc composite stabilizer, 1-2 parts lubricant, and 0.5-0.8 parts antioxidant.

2. The anti-torsion robot cable according to claim 1, characterized in that, The preparation process of the multifunctional additive is as follows: A1: Mix N-acetyl-L-alanine, L-lactic acid, and p-toluenesulfonic acid, stir until homogeneous, heat to 120℃, stir under normal pressure for 1-2 hours, then continue to heat to 150℃ and maintain the temperature for 6-7 hours. After the reaction is complete, stop heating, cool to 80℃, adjust the pH to 5-6 with dilute NaHCO3 solution, distill under reduced pressure for 1-2 hours, and filter under reduced pressure while hot to obtain intermediate A. A2: Under a protective atmosphere, intermediate A was added to chloroform and stirred evenly at room temperature. Then, thionyl chloride was slowly added dropwise. After the addition was complete, the temperature was raised to 65°C and the mixture was refluxed for 4-5 hours. After the reaction was completed, the solvent and filtered thionyl chloride were removed by rotary evaporation to obtain intermediate B. A3: Dissolve 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide and triethylamine in chloroform and stir until homogeneous to obtain solution A; dissolve intermediate B in chloroform and stir until homogeneous to obtain solution B; under a protective atmosphere, slowly add solution B dropwise to solution A. After the addition is complete, raise the temperature to 70℃ and reflux for 20-24 hours. After the reaction is complete, wash three times with deionized water to remove triethylamine hydrochloride and unreacted raw materials. Dry the organic phase with anhydrous magnesium sulfate, remove the solvent by rotary evaporation, and dry to obtain a multifunctional additive.

3. The anti-torsion robot cable according to claim 2, characterized in that, The raw materials for preparing intermediate A include the following components: by weight, 130-140 parts of N-acetyl-L-alanine, 95-98 parts of L-lactic acid, and 2-3 parts of p-toluenesulfonic acid.

4. The anti-torsion robot cable according to claim 2, characterized in that, The raw materials for preparing intermediate B include the following components: by weight, 10-12 parts intermediate A, 50-60 parts chloroform, and 6-8 parts thionyl chloride.

5. The anti-torsion robot cable according to claim 2, characterized in that, The raw materials for preparing solution A include the following components: by weight, 3-5 parts of 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, 1-2 parts of triethylamine, and 80-100 parts of chloroform; the raw materials for preparing solution B include the following components: by weight, 4-5 parts of intermediate B and 60-80 parts of chloroform.

6. The anti-torsion robot cable according to claim 1, characterized in that, The lubricant includes one or more of stearic acid and polyethylene wax.

7. The anti-torsion robot cable according to claim 1, characterized in that, The antioxidant includes one or more of antioxidant 168 and antioxidant 2246.

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