An antistatic flexible connection and a method of making

Abstract

The application provides an antistatic flexible connection and a preparation method, and the antistatic flexible connection comprises a flange and a connecting piece connected with the flange, and the connecting piece is composed of a middle buffer layer and antistatic functional layers arranged on both sides of the middle buffer layer; the antistatic functional layer is composed of the following components in parts by weight: 5-10 parts of a conductive polymer, 2-5 parts of an interface modifier, 1-3 parts of a self-made antioxidant, 35-45 parts of inorganic filler modified polyurethane elastomer, 10-18 parts of functional fillers, 3-6 parts of fluorosilicone, 5-9 parts of melamine cyanurate, 8-12 parts of nano kaolin and 2-5 parts of polyethylene glycol diacrylate. Through reasonable collocation and synergistic effect of the components, the antistatic flexible connection has excellent performance in antistatic property, mechanical property, flame retardancy, aging resistance and the like, and meets the use requirements under complex working conditions.

Description

Technical Field

[0001] This invention relates to the field of flexible connection structure technology, specifically to an antistatic flexible connection and its preparation method. Background Technology

[0002] In industrial production, antistatic flexible connectors are widely used in the connection of pipeline systems such as powder conveying and gas transmission. They need to simultaneously meet the requirements of excellent antistatic performance, good mechanical properties (such as tensile strength and elongation at break) and long service life to adapt to complex working environments.

[0003] However, existing antistatic flexible connectors often suffer from the problem of balancing antistatic effect with mechanical performance stability: some products achieve a certain antistatic capability by adding a single conductive filler, but under long-term use or external force, the material is prone to mechanical performance decline due to loose internal structure, and the antistatic performance will decay over time; other products use complex cross-linking systems to enhance mechanical performance, but the uneven dispersion of conductive components greatly reduces the antistatic performance, making it impossible to meet the stringent requirements of electrostatic control in high-precision production scenarios.

[0004] Therefore, developing an antistatic soft connector that can simultaneously guarantee excellent and durable antistatic properties, stable mechanical properties, and good synergistic effects among its components has become an urgent technical problem to be solved. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides an antistatic flexible connector and its preparation method.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This application discloses an antistatic flexible connector, including a flange and a connector for the flange. The connector consists of an intermediate buffer layer and antistatic functional layers disposed on both sides of the intermediate buffer layer. By weight, the antistatic functional layers are composed of the following: 5-10 parts of conductive polymer, 2-5 parts of interface modifier, 1-3 parts of self-made antioxidant, 35-45 parts of inorganic filler-modified polyurethane elastomer, 10-18 parts of functional filler, 3-6 parts of fluorosiloxane, 5-9 parts of melamine cyanurate, 8-12 parts of nano-kaolin, and 2-5 parts of polyethylene glycol diacrylate.

[0008] Preferably, the antistatic functional layer is composed of the following components: 7 parts conductive polymer, 3 parts interface modifier, 2 parts self-made antioxidant, 40 parts inorganic filler modified polyurethane elastomer, 14 parts functional filler, 5 parts fluorosiloxane, 7 parts melamine cyanurate, 10 parts nano kaolin and 3 parts polyethylene glycol diacrylate.

[0009] By employing the aforementioned technical solutions, inorganic filler-modified polyurethane elastomer, as the matrix material, possesses excellent elasticity and mechanical properties, providing fundamental structural support for flexible connections. The amino and ester groups in its molecular chain can form hydrogen bonds with other components, enhancing interfacial bonding. The fluorine groups and silicon-oxygen segments in fluorosiloxane molecules reduce the surface energy of the material, decreasing charge accumulation on the surface, while their excellent weather resistance also extends the material's service life. Melamine cyanurate decomposes at high temperatures to produce inert gases, diluting oxygen concentration and forming an expanded carbon layer that blocks heat transfer, exhibiting excellent flame-retardant properties and improving the safety of flexible connections. The layered structure of nano-kaolin enhances the material's mechanical properties and heat resistance, acting as a nucleating agent during processing, improving the material's crystal morphology and processing performance. Polyethylene glycol diacrylate, as a crosslinking agent, undergoes polymerization reactions during processing, forming a crosslinked network with other components, increasing the degree of crosslinking, and enhancing the material's structural stability and solvent resistance.

[0010] Preferably, the functional filler is composed of titanium carbide nanosheets and barium titanate nanoparticles in a mass ratio of 1.2-1.5:1.

[0011] By employing the aforementioned technical solutions, titanium carbide nanosheets exhibit excellent electrical conductivity. Their sheet-like structure can form continuous conductive pathways within the material, enhancing antistatic properties. Simultaneously, their high strength also strengthens the material's mechanical properties. Barium titanate nanoparticles possess a high dielectric constant, enhancing the material's polarization capability. Under an electric field, they form electric dipoles, facilitating rapid charge dissipation and synergistically improving the antistatic effect in conjunction with the conductive components.

[0012] Preferably, the conductive polymer is prepared as follows: aniline and pyrrole are mixed at a mass ratio of 2:1 and added to a 1 mol / L hydrochloric acid solution. The mixture is stirred at 280-300 r / min for 25-30 min until homogeneous. Then, ammonium persulfate is added as an initiator, with a mass ratio of ammonium persulfate to the mixed monomers of 1:1.5. The stirring speed is maintained at 280-300 r / min, and the reaction is carried out at 0-5℃ for 8-10 h. After the reaction is completed, stirring is stopped, and the product is filtered to obtain the product. The product is repeatedly washed with deionized water until the filtrate is neutral. The washed product is then placed in a vacuum drying oven and dried at 60-80℃ and a vacuum degree of -0.09 MPa for 12-16 h to obtain the conductive polymer.

[0013] By setting up the above technical solution, the conductive polymer has excellent conductivity. The conjugated structure in its molecular chain can form a synergistic effect with the titanium carbide nanosheets in the functional filler to build a more complete conductive network, significantly improving the antistatic effect. At the same time, its good compatibility can also enhance the bonding force with the matrix.

[0014] Preferably, the preparation method of the interface modifier is as follows: maleic anhydride-grafted polypropylene and γ-glycidyl etheroxypropyltrimethoxysilane are added to xylene solvent at a mass ratio of 3:1, and 0.5-1 part of dicumyl peroxide is added as an initiator. The mixture is stirred at a speed of 250-280 r / min and reacted at 120-140℃ for 4-6 h. After the reaction is completed, the reaction solution is transferred to a rotary evaporator and subjected to vacuum distillation at a vacuum degree of -0.09 MPa and a temperature of 80-100℃ to remove the solvent, thereby obtaining the interface modifier.

[0015] By setting up the above technical solution, the interface modifier molecule contains functional groups that can react with inorganic fillers and organic matrix, which can improve the interfacial compatibility between components, promote the uniform dispersion of components, reduce interfacial defects, and improve the comprehensive performance of materials.

[0016] The preferred method for preparing the homemade antioxidant is as follows: 2,2'-methylenebis(4-methyl-6-tert-butylphenol) and triphenyl phosphite are mixed at a mass ratio of 4:1 and added to a reaction vessel. The mixture is stirred at a speed of 180-200 r / min and heated to 150-170℃ under nitrogen protection. The reaction is carried out for 3-5 hours. After the reaction is completed, stirring is stopped and the mixture is allowed to cool naturally to room temperature to obtain the homemade antioxidant.

[0017] By setting up the above technical solution, the phenolic hydroxyl groups and phosphite groups in the self-made antioxidant molecules can capture free radicals, interrupt the oxidation chain reaction, effectively inhibit the oxidative aging of materials during processing and use, and extend the service life of flexible connections.

[0018] This application also discloses a method for preparing an antistatic flexible connection, comprising the following steps:

[0019] S1. Inorganic filler modified polyurethane elastomer is added to a twin-screw extruder and melt-plasticized at 180-200℃. Titanium carbide nanosheets, barium titanate nanoparticles, conductive polymer, interface modifier, fluorosiloxane, melamine cyanurate, nano-kaolin, self-made antioxidant and polyethylene glycol diacrylate are added in sequence. The mixture is co-extruded at a screw speed of 250-350 r / min and granulated to obtain antistatic functional layer material particles.

[0020] S2. Using a three-layer co-extrusion process, the material of the middle buffer layer is placed in the middle, and antistatic functional layer material particles are extruded from both sides simultaneously. The extrusion molding is carried out at a temperature of 200-220℃ to obtain a connector with a specific wall thickness and outer diameter.

[0021] S3. The prepared connectors are connected to the flange by hot-melt welding to form an antistatic flexible connection.

[0022] Preferably, the intermediate buffer layer is made of nitrile rubber with a thickness of 4-7 mm.

[0023] Preferably, the wall thickness of the connector is 7-11 mm and the outer diameter is 400-2000 mm.

[0024] Preferably, the welding temperature for hot melt welding is 220-240℃, the pressure is 4-6MPa, and the holding time is 3-5min.

[0025] The beneficial effects of this invention are as follows:

[0026] The components work synergistically through multiple mechanisms to form a high-performance antistatic flexible bonding material. Inorganic filler-modified polyurethane elastomer serves as the matrix; its molecular chains react with the interface modifier, enhancing the interfacial bonding with other components and providing a solid foundation for the material's excellent elastic and mechanical properties.

[0027] Titanium carbide nanosheets and conductive polymers in the functional filler are bonded together through π-π stacking and van der Waals forces to form a highly efficient three-dimensional conductive network. Barium titanate nanoparticles are dispersed in this network, and their high dielectric constant creates a strong electric field around the conductive network, accelerating charge migration and dissipation. The synergistic effect of these three elements gives the material excellent antistatic properties.

[0028] Fluorosiloxanes are adsorbed onto the material surface through intermolecular forces, forming a low surface energy film. This reduces the accumulation of external charges on the material surface, further improving the stability of the antistatic effect. Melamine cyanurate is uniformly dispersed in the matrix. When exposed to high temperatures, it works synergistically with the matrix material to rapidly form an expanded char layer, while simultaneously releasing inert gas. This effectively blocks flame and heat transfer, giving the material excellent flame-retardant properties.

[0029] The layered structure of nano-kaolinite is intertwined with the matrix molecular chains, which can disperse stress under external force. Synergistically, it works with the cross-linked network formed by polyethylene glycol diacrylate to significantly enhance the material's tensile strength and elongation at break, among other mechanical properties. The self-made antioxidant continuously captures free radicals during material processing and use, forming a stable structure with active groups in other components, effectively inhibiting oxidative aging and ensuring the long-term stability of the material's properties.

[0030] This invention, through the rational combination and synergistic effect of its components, enables the antistatic flexible connector to exhibit excellent performance in terms of antistatic properties, mechanical properties, flame retardancy, and aging resistance, thus meeting the requirements for use under complex working conditions. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of the antistatic flexible connection in this invention;

[0032] Figure 2 This is a planar schematic diagram of the antistatic flexible connection in this invention;

[0033] Figure 3 yes Figure 2 Enlarged diagram of point A in the middle.

[0034] In the diagram: 1. Flange; 2. Connector; 21. Intermediate buffer layer; 22. Antistatic functional layer. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1: As Figure 1-3 As shown, this embodiment discloses an antistatic flexible connection, including a flange 1 and a connector 2 for connecting the flange 1. The connector 2 is composed of an intermediate buffer layer 21 and an antistatic functional layer 22 disposed on both sides of the intermediate buffer layer 21.

[0037] The antistatic functional layer 22 is composed of the following components by weight: 5 parts conductive polymer, 2 parts interface modifier, 1 part self-made antioxidant, 35 parts inorganic filler modified polyurethane elastomer, 6 parts titanium carbide nanosheets, 4 parts barium titanate nanoparticles, 3 parts fluorosiloxane, 5 parts melamine cyanurate, 8 parts nano kaolin, and 2 parts polyethylene glycol diacrylate.

[0038] The conductive polymer is prepared as follows: Aniline and pyrrole are mixed at a mass ratio of 2:1 and added to a 1 mol / L hydrochloric acid solution. The mixture is stirred at 280 r / min for 25 min until homogeneous. Then, ammonium persulfate is added as an initiator, with a mass ratio of ammonium persulfate to the mixed monomers of 1:1.5. The stirring speed is maintained at 280 r / min, and the reaction is carried out at 0℃ for 8 h. After the reaction is completed, stirring is stopped, and the product is filtered to obtain the product. The product is washed repeatedly with deionized water until the filtrate is neutral. The washed product is then placed in a vacuum drying oven and dried at 60℃ and a vacuum degree of -0.09 MPa for 12 h to obtain the conductive polymer.

[0039] The interface modifier is prepared as follows: Maleic anhydride-grafted polypropylene and γ-glycidyl etheroxypropyltrimethoxysilane are added to xylene solvent at a mass ratio of 3:1. 0.5 parts of dicumyl peroxide are added as an initiator. The mixture is stirred at 250 r / min and reacted at 120℃ for 4 h. After the reaction is completed, the reaction solution is transferred to a rotary evaporator and subjected to vacuum distillation at a vacuum degree of -0.09 MPa and a temperature of 80℃ to remove the solvent, thus obtaining the interface modifier.

[0040] The method for preparing the homemade antioxidant is as follows: 2,2'-methylenebis(4-methyl-6-tert-butylphenol) and triphenyl phosphite are mixed at a mass ratio of 4:1 and added to a reaction vessel. The mixture is stirred at a speed of 180 r / min and heated to 150℃ under nitrogen protection for 3 h. After the reaction is completed, stirring is stopped and the mixture is allowed to cool naturally to room temperature to obtain the homemade antioxidant.

[0041] This embodiment also discloses a method for preparing an antistatic flexible connection, which includes the following steps:

[0042] S1. Inorganic filler modified polyurethane elastomer is added to a twin-screw extruder and melted and plasticized at 180°C. Titanium carbide nanosheets, barium titanate nanoparticles, conductive polymer, interface modifier, fluorosiloxane, melamine cyanurate, nano-kaolin, self-made antioxidant and polyethylene glycol diacrylate are added in sequence. The mixture is co-extruded at a screw speed of 250 r / min and granulated to obtain antistatic functional layer 22 material particles.

[0043] S2. Using a three-layer co-extrusion process, a 4mm thick intermediate buffer layer 21 made of nitrile rubber is placed in the middle, and antistatic functional layer 22 material particles are extruded from both sides simultaneously. The extrusion molding is carried out at a temperature of 200℃ to obtain a connector 2 with a wall thickness of 7mm and an outer diameter of 400mm.

[0044] S3. The prepared connector 2 is connected to the flange 1 by hot-melt welding. The welding temperature is 220℃, the pressure is 4MPa, and the pressure holding time is 3min to form an antistatic flexible connection.

[0045] Example 2: As Figure 1-3 As shown, this embodiment discloses an antistatic flexible connection, including a flange 1 and a connector 2 for connecting the flange 1. The connector 2 is composed of an intermediate buffer layer 21 and an antistatic functional layer 22 disposed on both sides of the intermediate buffer layer 21.

[0046] The antistatic functional layer 22 is composed of the following components by weight: 10 parts conductive polymer, 5 parts interface modifier, 3 parts self-made antioxidant, 45 parts inorganic filler modified polyurethane elastomer, 9.6 parts titanium carbide nanosheets, 8 parts barium titanate nanoparticles, 6 parts fluorosiloxane, 9 parts melamine cyanurate, 12 parts nano kaolin, and 5 parts polyethylene glycol diacrylate.

[0047] The conductive polymer is prepared as follows: Aniline and pyrrole are mixed at a mass ratio of 2:1 and added to a 1 mol / L hydrochloric acid solution. The mixture is stirred at 300 r / min for 30 min until homogeneous. Then, ammonium persulfate is added as an initiator, with a mass ratio of ammonium persulfate to the mixed monomers of 1:1.5. The stirring speed is maintained at 300 r / min, and the reaction is carried out at 5℃ for 10 h. After the reaction is completed, stirring is stopped, and the product is filtered to obtain the product. The product is washed repeatedly with deionized water until the filtrate is neutral. The washed product is then placed in a vacuum drying oven and dried at 80℃ and a vacuum degree of -0.09 MPa for 16 h to obtain the conductive polymer.

[0048] The preparation method of the interface modifier is as follows: maleic anhydride-grafted polypropylene and γ-glycidyl etheroxypropyltrimethoxysilane are added to xylene solvent at a mass ratio of 3:1. One part of dicumyl peroxide is added as an initiator. The mixture is stirred at 280 r / min and reacted at 140℃ for 6 h. After the reaction is completed, the reaction solution is transferred to a rotary evaporator and subjected to vacuum distillation at a vacuum degree of -0.09 MPa and a temperature of 100℃ to remove the solvent, thereby obtaining the interface modifier.

[0049] The method for preparing the homemade antioxidant is as follows: 2,2'-methylenebis(4-methyl-6-tert-butylphenol) and triphenyl phosphite are mixed at a mass ratio of 4:1 and added to a reaction vessel. The mixture is stirred at a speed of 200 r / min and heated to 170℃ under nitrogen protection for 5 h. After the reaction is completed, stirring is stopped and the mixture is allowed to cool naturally to room temperature to obtain the homemade antioxidant.

[0050] This embodiment also discloses a method for preparing an antistatic flexible connection, which includes the following steps:

[0051] S1. Inorganic filler modified polyurethane elastomer is added to a twin-screw extruder and melted and plasticized at 200℃. Titanium carbide nanosheets, barium titanate nanoparticles, conductive polymer, interface modifier, fluorosiloxane, melamine cyanurate, nano-kaolin, self-made antioxidant and polyethylene glycol diacrylate are added in sequence. The mixture is co-extruded at a screw speed of 350 r / min and granulated to obtain antistatic functional layer 22 material particles.

[0052] S2. Using a three-layer co-extrusion process, a 7mm thick intermediate buffer layer 21 made of nitrile rubber is placed in the middle, and antistatic functional layer 22 material particles are extruded from both sides simultaneously. The extrusion molding is carried out at a temperature of 220℃ to obtain a connector 2 with a wall thickness of 11mm and an outer diameter of 2000mm.

[0053] S3. The prepared connector 2 is connected to the flange 1 by hot-melt welding at a temperature of 240℃, a pressure of 6MPa, and a holding time of 5min to form an antistatic flexible connection.

[0054] Example 3: As Figure 1-3 As shown, this embodiment discloses an antistatic flexible connection, including a flange 1 and a connector 2 for connecting the flange 1. The connector 2 is composed of an intermediate buffer layer 21 and an antistatic functional layer 22 disposed on both sides of the intermediate buffer layer 21.

[0055] The antistatic functional layer 22 is composed of the following components by weight: 7 parts conductive polymer, 3 parts interface modifier, 2 parts self-made antioxidant, 40 parts inorganic filler modified polyurethane elastomer, 7 parts titanium carbide nanosheets, 5 parts barium titanate nanoparticles, 5 parts fluorosiloxane, 7 parts melamine cyanurate, 10 parts nano kaolin, and 3 parts polyethylene glycol diacrylate.

[0056] The conductive polymer is prepared as follows: Aniline and pyrrole are mixed at a mass ratio of 2:1 and added to a 1 mol / L hydrochloric acid solution. The mixture is stirred at 290 r / min for 27 min until homogeneous. Then, ammonium persulfate is added as an initiator, with a mass ratio of ammonium persulfate to the mixed monomers of 1:1.5. The stirring speed is maintained at 290 r / min, and the reaction is carried out at 2℃ for 9 h. After the reaction is completed, stirring is stopped, and the product is filtered to obtain the product. The product is washed repeatedly with deionized water until the filtrate is neutral. The washed product is then placed in a vacuum drying oven and dried at 70℃ and a vacuum degree of -0.09 MPa for 14 h to obtain the conductive polymer.

[0057] The preparation method of the interface modifier is as follows: Maleic anhydride-grafted polypropylene and γ-glycidyl etheroxypropyltrimethoxysilane are added to xylene solvent at a mass ratio of 3:1. 0.7 parts of dicumyl peroxide are added as an initiator. The mixture is stirred at a speed of 265 r / min and reacted at 130℃ for 5 h. After the reaction is completed, the reaction solution is transferred to a rotary evaporator and subjected to vacuum distillation at a vacuum degree of -0.09 MPa and a temperature of 90℃ to remove the solvent, thereby obtaining the interface modifier.

[0058] The method for preparing the homemade antioxidant is as follows: 2,2'-methylenebis(4-methyl-6-tert-butylphenol) and triphenyl phosphite are mixed at a mass ratio of 4:1 and added to a reaction vessel. The mixture is stirred at a speed of 190 r / min and heated to 160℃ under nitrogen protection. The reaction is carried out for 4 hours. After the reaction is completed, stirring is stopped and the mixture is allowed to cool naturally to room temperature to obtain the homemade antioxidant.

[0059] This embodiment also discloses a method for preparing an antistatic flexible connection, which includes the following steps:

[0060] S1. Inorganic filler modified polyurethane elastomer is added to a twin-screw extruder and melted and plasticized at 190°C. Titanium carbide nanosheets, barium titanate nanoparticles, conductive polymer, interface modifier, fluorosiloxane, melamine cyanurate, nano-kaolin, self-made antioxidant and polyethylene glycol diacrylate are added in sequence. The mixture is co-extruded at a screw speed of 300 r / min and granulated to obtain antistatic functional layer 22 material particles.

[0061] S2. Using a three-layer co-extrusion process, a 5mm thick intermediate buffer layer 21 made of nitrile rubber is placed in the middle, and antistatic functional layer 22 material particles are extruded from both sides simultaneously. The extrusion molding is carried out at a temperature of 210℃ to obtain a connector 2 with a wall thickness of 9mm and an outer diameter of 1200mm.

[0062] S3. The prepared connector 2 is connected to the flange 1 by hot-melt welding at a temperature of 230℃, a pressure of 5MPa, and a holding time of 4min to form an antistatic flexible connection.

[0063] Comparative Example 1:

[0064] An antistatic flexible connector, which differs from Example 3 only in that no conductive polymer is added.

[0065] Comparative Example 2:

[0066] An antistatic flexible connector, which differs from Example 3 only in that no interface modifier is added.

[0067] Comparative Example 3:

[0068] An antistatic flexible connector, which differs from Example 3 only in that no homemade antioxidant is added.

[0069] Comparative Example 4:

[0070] An antistatic flexible connector, which differs from Example 3 only in that: no titanium carbide nanosheets are added.

[0071] Comparative Example 5:

[0072] An antistatic flexible connector, which differs from Example 3 only in that barium titanate nanoparticles are not added.

[0073] Comparative Example 6:

[0074] An antistatic flexible connector, which differs from Example 3 only in that no fluorosiloxane is added.

[0075] Comparative Example 7:

[0076] An antistatic flexible connector, which differs from Example 3 only in that melamine cyanurate is not added.

[0077] Comparative Example 8:

[0078] An antistatic flexible connector, which differs from Example 3 only in that: no nano-kaolin is added.

[0079] Comparative Example 9:

[0080] An antistatic flexible connector, which differs from Example 3 only in that polyethylene glycol diacrylate is not added.

[0081] Comparative Example 10:

[0082] An antistatic flexible connector, which differs from Example 3 only in that the twin-screw extruder has a screw speed of 200 r / min.

[0083] Comparative Example 11:

[0084] An antistatic flexible connector, which differs from Example 3 only in that the three-layer co-extrusion temperature is 180°C.

[0085] Comparative Example 12:

[0086] An antistatic flexible connector, which differs from Example 3 only in that the hot melt welding temperature is 200°C.

[0087] The antistatic flexible connections obtained in Examples 1-3 and Comparative Examples 1-12 were subjected to surface resistivity, tensile strength and elongation at break, flame retardancy rating, and anti-aging performance tests, among which:

[0088] Surface resistivity: Tested according to GB / T1410-2006 "Test Methods for Volume Resistivity and Surface Resistivity of Solid Insulating Materials". A 100mm × 100mm sample was cut from the antistatic functional layer of the antistatic flexible connector. The sample surface was wiped clean with anhydrous ethanol and placed in an environment with a temperature of 23±2℃ and a relative humidity of 50±5% for 24 hours. The two electrodes of the high-resistivity meter were placed at opposite ends of the sample surface, ensuring close contact between the electrodes and the sample surface. A DC voltage of 100V was applied, and the surface resistivity value was recorded after the reading stabilized.

[0089] Tensile strength and elongation at break: Tested according to GB / T1040.2-2006 "Determination of tensile properties of plastics - Part 2: Test conditions for molded and extruded plastics". A standard dumbbell-shaped specimen was cut from the antistatic flexible connector, with a gauge length of 50 mm and a width of 10 mm. The specimen was mounted on the fixture of the universal testing machine, ensuring the specimen axis was aligned with the tensile direction. Tensioning was performed at a speed of 50 mm / min until the specimen broke. The maximum tensile force at break and the elongation of the gauge length were recorded. Tensile strength and elongation at break were calculated using the formulas.

[0090] Flame retardancy rating: Tested according to the vertical burning method in GB / T2408-2008 "Determination of Burning Performance of Plastics - Horizontal and Vertical Methods". A 125mm × 13mm sample with the actual thickness of the specimen is cut from the antistatic functional layer of the antistatic flexible connector. The sample is vertically fixed in the combustion test chamber, and the bottom of the sample is ignited with a specified ignition source for 10 seconds. The ignition source is then removed, and the burning of the sample is observed. The burning time, whether dripping occurs, and whether the dripping material ignites the cotton pad below are recorded. The flame retardancy rating is determined according to the standard.

[0091] Anti-aging performance: Tensile specimens cut from the antistatic flexible connector were placed in a thermal aging test chamber and aged at 120℃ for 1000 hours. After aging, the specimens were removed and cooled in an environment with a temperature of 23±2℃ and a relative humidity of 50±5% for 24 hours. The tensile strength of the aged specimens was tested according to the above tensile strength test method, and the tensile strength retention rate after aging was calculated, which is the ratio of the tensile strength after aging to the tensile strength before aging multiplied by 100%.

[0092] The test results for each performance parameter are shown in Table 1.

[0093] Table 1 Performance parameters of antistatic flexible connections obtained in Examples 1-3 and Comparative Examples 1-12

[0094]

[0095] As shown in Table 1:

[0096] Comparative Example 1, without the addition of conductive polymer (PAS), had a surface resistivity that was 9.8 × 10⁻⁶ in Example 3. 4 Ω increased sharply to 5.8 × 10 8The reason for this is that PAS and titanium carbide nanosheets synergistically construct a conductive network. The absence of PAS leads to an incomplete conductive network, hindering electron transport and significantly reducing antistatic properties. Simultaneously, tensile strength and elongation at break are also significantly reduced. Since PAS has good interfacial bonding with the matrix and other components, its absence disrupts the integrity of the material's internal structure, resulting in decreased mechanical properties.

[0097] Comparative Example 2, without the addition of interfacial modifier (IMS), showed an increase in surface resistivity to 3.5 × 10⁻⁶. 7 The tensile strength and elongation at break decrease significantly because IMS can improve the compatibility of each component. Its absence leads to uneven dispersion of each component and agglomeration, which disrupts the continuity of the conductive network and material structure, thereby reducing both antistatic and mechanical properties.

[0098] Comparative Example 3, without the addition of the self-made antioxidant (AOA), showed a decrease in tensile strength retention from 93% in Example 3 to 65% after aging, while the change in surface resistivity was relatively small. This is because AOA can effectively inhibit the oxidative aging of the material. Its absence causes the molecular chains of the material to break during high-temperature aging, resulting in a significant decrease in mechanical properties, but has little impact on antistatic properties.

[0099] Comparative Example 4, without the addition of titanium carbide nanosheets, exhibits a surface resistivity as high as 6.2 × 10⁻⁶. 8 The antistatic properties deteriorate significantly because titanium carbide nanosheets are a crucial component of the conductive network; their absence drastically reduces conductive pathways, hindering efficient electron transport. Simultaneously, mechanical properties also decline, as the reinforcing effect of the titanium carbide nanosheets disappears, reducing the material's load-bearing capacity.

[0100] Comparative Example 5, without the addition of barium titanate nanoparticles, showed a surface resistivity that increased to 4.8 × 10⁻⁶. 6 The antistatic properties decrease because the high dielectric constant of barium titanate helps dissipate charge, and its absence slows down charge migration in the conductive network. Mechanical properties also decrease slightly, possibly due to the disappearance of the reinforcing effect of barium titanate particles on the material structure.

[0101] Comparative Example 6, without the addition of fluorosiloxane, showed an increase in surface resistivity to 2.2 × 10⁻⁶. 6 Ω, because fluorosiloxanes can reduce the accumulation of charge on the surface, their absence makes the surface more prone to charge accumulation, leading to a decrease in antistatic properties. The mechanical properties do not change significantly, indicating that fluorosiloxanes mainly affect surface properties.

[0102] Comparative Example 7, without the addition of melamine cyanurate, saw its flame retardant rating drop from V-0 to V-2. This is because melamine cyanurate is the main flame retardant component, and its absence prevents the material from forming an effective flame retardant barrier during combustion, resulting in a decrease in flame retardant performance. However, it has little impact on antistatic and mechanical properties.

[0103] Comparative Example 8, without the addition of nano-kaolin, showed a significant decrease in tensile strength to 20 MPa and elongation at break to 240%, resulting in a substantial drop in mechanical properties. Since the layered structure of nano-kaolin can enhance the strength and toughness of the material, its absence weakens the structural support of the material, while having a relatively small impact on antistatic properties.

[0104] In Comparative Example 9, without the addition of polyethylene glycol diacrylate, both tensile strength and elongation at break decreased. This is because polyethylene glycol diacrylate, as a crosslinking agent, can improve the degree of crosslinking of the material and enhance structural stability. Its absence resulted in an incomplete crosslinking network and decreased mechanical properties. At the same time, the surface resistivity also increased slightly, possibly because the lack of crosslinking structure affected the distribution of conductive components.

[0105] In Comparative Example 10, when the screw speed of the twin-screw extruder was reduced to 200 r / min, the surface resistivity increased to 4.2 × 10⁻⁶. 6 The mechanical properties decreased because the low rotation speed caused uneven mixing of the components, uneven dispersion of conductive components, and an imperfect conductive network. At the same time, the uniformity of the internal structure of the material was also affected, resulting in a decrease in mechanical properties.

[0106] When the co-extrusion temperature of the three layers in Comparative Example 11 was reduced to 180℃, the surface resistivity and mechanical properties both decreased. This was because the material was not fully plasticized due to the low temperature, which weakened the bonding force between the layers, resulting in a loose structure and affecting the continuity of the conductive network and the overall performance of the material.

[0107] When the hot-melt welding temperature of Comparative Example 12 was reduced to 200℃, the tensile strength and elongation at break decreased because the welding temperature was too low, resulting in a weak bond between the connector and the flange and interface defects. Under stress, the connector was prone to breakage at the interface, while the antistatic properties were less affected.

[0108] In summary, changes in each component and process parameter will affect the material's performance to varying degrees. Only when the components work synergistically and the process parameters are reasonable can the excellent performance shown in Example 3 be obtained.

[0109] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An antistatic flexible connector, characterized in that, The connector (2) includes a flange (1) and a connecting flange (1). The connector (2) is composed of an intermediate buffer layer (21) and an antistatic functional layer (22) disposed on both sides of the intermediate buffer layer (21). The composition of the antistatic functional layer (22) by weight is as follows: 5-10 parts of conductive polymer, 2-5 parts of interface modifier, 1-3 parts of self-made antioxidant, 35-45 parts of inorganic filler modified polyurethane elastomer, 10-18 parts of functional filler, 3-6 parts of fluorosiloxane, 5-9 parts of melamine cyanurate, 8-12 parts of nano-kaolin and 2-5 parts of polyethylene glycol diacrylate; The preparation method of the interface modifier is as follows: Maleic anhydride-grafted polypropylene and γ-glycidyl etheroxypropyltrimethoxysilane are added to xylene solvent at a mass ratio of 3:

1. 0.5-1 part of dicumyl peroxide is added as an initiator. The mixture is stirred at a speed of 250-280 r / min and reacted at 120-140℃ for 4-6 h. After the reaction is completed, the reaction solution is transferred to a rotary evaporator and subjected to vacuum distillation at a vacuum degree of -0.09 MPa and a temperature of 80-100℃ to remove the solvent, thereby obtaining the interface modifier. The method for preparing the homemade antioxidant is as follows: 2,2'-methylenebis(4-methyl-6-tert-butylphenol) and triphenyl phosphite are mixed at a mass ratio of 4:1 and added to a reaction vessel. The mixture is stirred at a speed of 180-200 r / min and heated to 150-170℃ under nitrogen protection. The reaction is carried out for 3-5 hours. After the reaction is completed, stirring is stopped and the mixture is allowed to cool naturally to room temperature to obtain the homemade antioxidant. The functional filler is composed of titanium carbide nanosheets and barium titanate nanoparticles in a mass ratio of 1.2-1.5:1; The conductive polymer is prepared as follows: Aniline and pyrrole are mixed at a mass ratio of 2:1 and added to a 1 mol / L hydrochloric acid solution. The mixture is stirred at 280-300 r / min for 25-30 min until homogeneous. Then, ammonium persulfate is added as an initiator, with a mass ratio of ammonium persulfate to the mixed monomers of 1:1.

5. The stirring speed is maintained at 280-300 r / min, and the reaction is carried out at 0-5℃ for 8-10 h. After the reaction is completed, stirring is stopped, and the product is filtered to obtain the product. The product is washed repeatedly with deionized water until the filtrate is neutral. The washed product is then placed in a vacuum drying oven and dried at 60-80℃ and a vacuum degree of -0.09 MPa for 12-16 h to obtain the conductive polymer.

2. The antistatic flexible connector according to claim 1, characterized in that, The components of the antistatic functional layer (22) by weight are as follows: 7 parts conductive polymer, 3 parts interface modifier, 2 parts self-made antioxidant, 40 parts inorganic filler modified polyurethane elastomer, 14 parts functional filler, 5 parts fluorosiloxane, 7 parts melamine cyanurate, 10 parts nano kaolin and 3 parts polyethylene glycol diacrylate.

3. A method for preparing an antistatic flexible connector according to claim 1 or 2, characterized in that, The preparation method includes the following steps: S1. Add inorganic filler modified polyurethane elastomer to a twin-screw extruder and melt and plasticize it at 180-200℃. Then add titanium carbide nanosheets, barium titanate nanoparticles, conductive polymer, interface modifier, fluorosiloxane, melamine cyanurate, nano kaolin, self-made antioxidant and polyethylene glycol diacrylate in sequence. Blend and extrude at a screw speed of 250-350r / min and granulate to obtain antistatic functional layer (22) material particles. S2. Using a three-layer co-extrusion process, the material of the middle buffer layer (21) is placed in the middle, and the antistatic functional layer (22) material particles are extruded on both sides at the same time. The extrusion molding is carried out at a temperature of 200-220℃ to obtain the connector (2). The wall thickness of the connector (2) is 7-11mm and the outer diameter is 400-2000mm. S3. The prepared connector (2) is connected to the flange (1) by hot-melt welding to form an antistatic flexible connection.

4. The method for preparing an antistatic flexible connection according to claim 3, characterized in that, The intermediate buffer layer (21) is made of nitrile rubber with a thickness of 4-7 mm.

5. The method for preparing an antistatic flexible connection according to claim 3, characterized in that, The welding temperature for hot melt welding is 220-240℃, the pressure is 4-6MPa, and the holding time is 3-5min.

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