Ultrafine electromagnetic shielding metal wire for textile use and preparation method thereof

Abstract

The present invention relates to the technical field of metal wires, and discloses an ultrafine electromagnetic shielding metal wire for textiles and a preparation method thereof; a coil is taken, and subjected to drawing, annealing, drawing, annealing, drawing, annealing, drawing, drawing, and annealing to obtain an ultrafine metal wire of 0.03 mm, which has good strength and elongation; a modified filament is prepared, and the ultrafine metal wire is wrapped with the modified filament to obtain an ultrafine electromagnetic shielding metal wire for textiles; the modified filament comprises 10 to 20 parts of modified The invention discloses a novel ultrafine electromagnetic shielding metal wire for textile use, comprising: a conductive material, 80 to 90 parts of polylactic acid powder, and a modified additive comprising 120 to 150 parts of isophorone diisocyanate, 70 to 90 parts of polyethylene glycol, 10 to 20 parts of terminal hydroxyl hyperbranched polyester ether, 0.2 to 0.5 parts of dibutyltin dilaurate, 30 to 40 parts of carbonyl iron powder, 5 to 10 parts of carbonyl nickel powder, and 0.5 to 1.5 parts of isocyanate silane coupling agent; the obtained ultrafine electromagnetic shielding metal wire for textile use has a strong electromagnetic shielding capability.

Description

Technical Field

[0001] The invention relates to the technical field of metal wires and discloses an ultra-fine electromagnetic shielding metal wire for textile use and a preparation method thereof. Background Art

[0002] Electromagnetic radiation is harmful to the human body. With the popularization of electronic products, people have more and more opportunities to be exposed to electromagnetic radiation. Therefore, electromagnetic radiation has become one of the major sources of environmental pollution, and anti-electromagnetic interference fabrics have become a research hotspot.

[0003] Ultrafine metal wire has the inherent advantages of being a metal material and also has the spinnability of fiber, and is widely used in electromagnetic shielding materials. Existing anti-electromagnetic interference fabrics made by blending metal wire and fiber have some disadvantages, such as: (1) the ability of anti-electromagnetic interference fabrics made by blending metal wire and fiber to shield electromagnetic radiation in the low-frequency band needs to be improved; (2) due to the introduction of metal wire, the wearing comfort of anti-electromagnetic interference fabrics made by blending metal wire and fiber is reduced.

[0004] Therefore, it is of great significance to prepare an ultrafine electromagnetic shielding metal wire for textile use that has good electromagnetic wave shielding ability in various bands, is comfortable to use, and is durable. Summary of the Invention

[0005] The object of the present invention is to provide an ultra-fine electromagnetic shielding metal wire for textile use and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A method for preparing ultrafine electromagnetic shielding metal wire for textile use comprises the following steps: S1: taking a coil, and subjecting it to drawing, annealing, drawing, annealing, drawing, annealing, drawing, drawing, and annealing to obtain an ultrafine metal wire;

[0008] S2: preparing a modified additive by mixing isophorone diisocyanate, polyethylene glycol, terminal hydroxyl hyperbranched polyester ether, dibutyltin dilaurate, carbonyl iron powder, carbonyl nickel powder, and isocyanate silane coupling agent; mixing the modified additive and polylactic acid powder, and melt-blending and extruding the mixture to obtain a modified filament;

[0009] S3: The ultrafine metal wire is wrapped with modified filament to obtain ultrafine electromagnetic shielding metal wire for textile use.

[0010] More optimally, the specific preparation of the ultrafine metal wire includes the following steps: taking a 5.5mm coil, cold drawing at a speed of 60-70m / min, pulling the diameter from 5.5mm to 2.3mm, heating to 1100℃, holding for 1-2h, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a speed of 150℃ / h, cold drawing at a speed of 60-70m / min, pulling the diameter from 2.3mm to 1.0mm, heating to 1100℃, holding for 1-2h, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a speed of 150℃ / h, and cold drawing at a speed of 60-70m / min, pulling the diameter from 2.3mm to 1.0mm, heating to 1100℃, holding for 1-2h, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a speed of 150℃ / h, and cooling to room temperature at a speed of 60-70m / min. m / min, cold drawing is performed from 1.0 mm to 0.2 mm in diameter, heating to 1080°C, holding time is 1 to 2 h, after the holding is completed, nitrogen is introduced, cooling to room temperature at a rate of 150°C / h, cold drawing is performed at a rate of 60 to 70 m / min, pulling the diameter from 0.2 mm to 0.08 mm, cold drawing is performed at a rate of 60 to 70 m / min, pulling the diameter from 0.08 mm to 0.03 mm, heating to 980°C, holding time is 4 to 6 h, after the holding is completed, nitrogen is introduced, cooling to room temperature at a rate of 150°C / h, and ultrafine metal wire is obtained.

[0011] More optimally, the modified filament comprises the following raw materials, calculated by mass: 10 to 20 parts of modification additives and 80 to 90 parts of polylactic acid powder.

[0012] More optimally, the specific preparation of the modified additive includes the following steps: taking isophorone diisocyanate, polyethylene glycol, terminal hydroxyl hyperbranched polyester ether, and dibutyltin dilaurate, stirring at a uniform speed and heating to 75-90°C, maintaining this temperature for reaction for 3-4 hours, adding carbonyl iron powder, carbonyl nickel powder, and isocyanate silane coupling agent, maintaining 75-90°C and stirring for 1-2 hours to obtain the modified additive.

[0013] More optimally, the modifying additive includes the following raw materials, calculated by mass: 120-150 parts of isophorone diisocyanate, 70-90 parts of polyethylene glycol, 10-20 parts of terminal hydroxyl hyperbranched polyester ether, 0.2-0.5 parts of dibutyltin dilaurate, 30-40 parts of carbonyl iron powder, 5-10 parts of carbonyl nickel powder, and 0.5-1.5 parts of isocyanate silane coupling agent.

[0014] More optimally, the preparation of the terminal hydroxyl hyperbranched polyester ether includes the following steps: taking 3,5-dihydroxybenzoic acid, potassium carbonate, 1,6-dibromohexane, and N,N-dimethylformamide, stirring evenly, heating to 55-65°C and reacting for 10-15 hours, filtering the filtrate, precipitating the filtrate in water, and drying for 20-28 hours to obtain the terminal hydroxyl hyperbranched polyester ether.

[0015] More optimally, the terminal hydroxyl hyperbranched polyester ether includes the following raw materials, calculated by mass: 8 to 15 parts of 3,5-dihydroxybenzoic acid, 50 to 60 parts of potassium carbonate, 15 to 20 parts of 1,6-dibromohexane, and 80 to 100 parts of N,N-dimethylformamide.

[0016] More optimally, the ultrafine metal wire is wrapped with modified filaments, and the preparation method includes the following steps: opening and combing (cylinder speed 340r / min, licker-in speed 720r / min, doffer speed 15r / min), drawing (number of roots in the first drawing: 6, drafting ratio: 5.1; number of roots in the first drawing: 6, drafting ratio: 5.4;), coarse yarn (twist: 10 twists / m, rear zone drafting ratio 1.25, spindle speed 800r / min), and spun yarn (two coarse yarns are fed into the spun yarn frame, and the ultrafine metal wire is introduced into the guide wheel, and merged with the two coarse yarns at the jaws of the front roller, and spun yarn is formed under the action of twisting; the roller gauge is 20×40mm, the jaw gauge is 3.3mm, the spindle speed is 9000r / min, and the gathering negative pressure is 2000Pa). After the wrapping is completed, the ultrafine electromagnetic shielding metal wire for textile use is obtained.

[0017] More optimally, the preparation of the polylactic acid powder includes the following steps: taking polylactic acid particles and crushing them, passing them through a 300-mesh sieve, and drying them in a vacuum oven at 55-65° C. for 10-12 hours to obtain polylactic acid powder.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: (1) Production process: 5.5 mm coil - drawing to 2.3 mm - annealing (1100° C.) - drawing to 1.0 mm - annealing (1100° C.) - drawing to 0.2 mm - annealing (1080° C.) - drawing to 0.08 mm - drawing to 0.03 mm - annealing (980° C.) - ultrafine metal wire; this process makes the obtained ultrafine metal wire have high strength and good elongation.

[0019] (2) Add a modification additive to polylactic acid to prepare modified filaments, and use the modified filaments to wrap the ultrafine metal wire. Polylactic acid fiber has good UV resistance, moisture absorption, and antibacterial properties. It also has weak acidity that is beneficial to the skin and good skin affinity. Wrapping it around the ultrafine metal wire can improve comfort and practicality. However, polylactic acid has poor toughness. Therefore, a modification additive is prepared, including isophorone diisocyanate, polyethylene glycol, and terminal hydroxyl hyperbranched polyester ether. Polyethylene glycol is a low molecular weight polyethylene glycol with good compatibility with polylactic acid. Terminal hydroxyl hyperbranched polyester is used for toughening. Isophorone diisocyanate can make polyethylene glycol, End-hydroxy hyperbranched polyester ether and polylactic acid are cross-linked to reduce the interfacial tension between polylactic acid and the modifying additive, improve the compatibility of the system, and further enhance the toughness. Carbonyl iron powder, carbonyl nickel powder, and isocyanate silane coupling agent are added to the modifying additive. Carbonyl iron powder and carbonyl nickel powder can improve the shielding ability against electromagnetic interference in the low-frequency band, making up for the problem that ultrafine metal wire has weak electromagnetic radiation protection ability in the low-frequency band. Isocyanate silane coupling agent improves the compatibility of carbonyl iron powder, carbonyl nickel powder and the modifying additive.

[0020] (3) The amount of modified additives used is limited. Considering the compatibility issue, if too much is added, the elongation at break will decrease instead. The amount of isophorone diisocyanate added also needs to be controlled. Although isophorone diisocyanate can cross-link polyethylene glycol, end-hydroxy hyperbranched polyester ether, and polylactic acid to improve the compatibility of the system, if too much is added, the cross-linking will be complicated and chaotic, and it will be more likely to break during the stretching process, affecting the mechanical properties. DETAILED DESCRIPTION

[0021] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0022] The following examples include the following raw materials: 3,5-dihydroxybenzoic acid (CAS: 99-10-5); potassium carbonate (CAS: 584-08-7); 1,6-dibromohexane (CAS: 629-03-8); N,N-dimethylformamide (CAS: 68-12-2); isophorone diisocyanate (CAS: 4098-71-9); polyethylene glycol (polyethylene glycol 300, Shanghai Yuanye); dibutyltin dilaurate (CAS: 77-58-7); carbonyl iron powder (model: FTFN-50, Jiangyou Hebao Nanomaterial Co., Ltd.); carbonyl nickel powder (1-3 μm, Wuhan Jiangxinyu Biotechnology Co., Ltd.); isocyanate silane coupling agent (SCA-Y25E, Hubei Tosoh Chemical Technology Co., Ltd.); polylactic acid particles (S30789, Shanghai Yuanye); disk (5.5 mm);

[0023] The following parts are by mass;

[0024] Example 1: S1: Take a 5.5 mm round plate, cold-draw it at a speed of 65 m / min, pull the diameter from 5.5 mm to 2.3 mm, heat it to 1100 ° C, keep it at this temperature for 1 hour, after the heat preservation is completed, introduce nitrogen, cool it to room temperature at a speed of 150 ° C / h, cold-draw it at a speed of 65 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat it to 1100 ° C, keep it at this temperature for 1 hour, after the heat preservation is completed, introduce nitrogen, cool it to room temperature at a speed of 150 ° C / h, and cold-draw it at a speed of 65 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat it to 1100 ° C, keep it at this temperature for 1 hour, after the heat preservation is completed, introduce nitrogen, cool it to room temperature at a speed of 150 ° C / h, and cold-draw it at a speed of 65 m / min. Cold drawing, pulling the diameter from 1.0 mm to 0.2 mm, heating to 1080 ° C, holding time for 2 hours, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a rate of 150 ° C / h, cold drawing at a speed of 65 m / min, pulling the diameter from 0.2 mm to 0.08 mm, cold drawing at a speed of 65 m / min, pulling the diameter from 0.08 mm to 0.03 mm, heating to 980 ° C, holding time for 6 hours, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a rate of 150 ° C / h, to obtain ultrafine metal wire;

[0025] S2: Take 12 parts of 3,5-dihydroxybenzoic acid, 55 parts of potassium carbonate, 18 parts of 1,6-dibromohexane, and 90 parts of N,N-dimethylformamide, stir evenly, heat to 60°C for 12 hours, filter and take the filtrate, precipitate the filtrate in water, and dry for 24 hours to obtain terminal hydroxyl hyperbranched polyester ether; take 130 parts of isophorone diisocyanate, 75 parts of polyethylene glycol, 15 parts of terminal hydroxyl hyperbranched polyester ether, and 0.3 parts of dibutyltin dilaurate, stir evenly and heat to 85 ℃, keep the reaction at this temperature for 4 hours, add 40 parts of carbonyl iron powder, 8 parts of carbonyl nickel powder, and 1.5 parts of isocyanate silane coupling agent, keep stirring at 90℃ for 1 hour to obtain a modified additive; take polylactic acid particles, crush them, pass them through a 300-mesh sieve, and dry them in a vacuum oven at 60℃ for 12 hours to obtain polylactic acid powder; take 15 parts of the modified additive and 85 parts of polylactic acid powder, stir them evenly, melt blend them at 175℃ for 2 hours to obtain modified polylactic acid, and extrude them to obtain modified filaments with a fineness of 9tex;

[0026] S3: The ultrafine metal wire is wrapped with modified filament, and the preparation method includes the following steps: opening and combing (cylinder speed 340r / min, roller speed 720r / min, doffer speed 15r / min), drawing (number of roots in the first drawing: 6, drafting ratio: 5.1; number of roots in the first drawing: 6, drafting ratio: 5.4;), roving (twist: 10 twists / m, back zone drafting ratio 1.25, spindle speed 800r / min), spinning (two rovings are fed into the spinning frame, and the ultrafine metal wire is introduced into the guide wheel, and merged with the two rovings at the front roller jaws, and the spinning is performed under the action of twisting; the roller gauge is 20×40mm, the jaw gauge is 3.3mm, the spindle speed is 9000r / min, and the gathering negative pressure is 2000Pa). After the wrapping is completed, the ultrafine electromagnetic shielding metal wire for textile use is obtained.

[0027] Example 2: S1: Take a 5.5mm round plate, cold-draw it at a speed of 70m / min, pull the diameter from 5.5mm to 2.3mm, heat it to 1100℃, keep it at this temperature for 2h, after the end of the heat preservation, introduce nitrogen, cool it to room temperature at a speed of 150℃ / h, cold-draw it at a speed of 70m / min, pull the diameter from 2.3mm to 1.0mm, heat it to 1100℃, keep it at this temperature for 2h, after the end of the heat preservation, introduce nitrogen, cool it to room temperature at a speed of 150℃ / h, cold-draw it at a speed of 70m / min, pull the diameter from 2.3mm to 1.0mm, heat it to 1100℃, keep it at this temperature for 2h, after the end of the heat preservation, introduce nitrogen, cool it to room temperature at a speed of 150℃ / h, cold-draw it at a speed of 70m / min Cold drawing, pulling the diameter from 1.0 mm to 0.2 mm, heating to 1080 ° C, holding time for 2 hours, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a rate of 150 ° C / h, cold drawing at a speed of 70 m / min, pulling the diameter from 0.2 mm to 0.08 mm, cold drawing at a speed of 70 m / min, pulling the diameter from 0.08 mm to 0.03 mm, heating to 980 ° C, holding time for 4 hours, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a rate of 150 ° C / h, to obtain ultrafine metal wire;

[0028] S2: Take 15 parts of 3,5-dihydroxybenzoic acid, 60 parts of potassium carbonate, 20 parts of 1,6-dibromohexane, and 100 parts of N,N-dimethylformamide, stir evenly, heat to 60°C for 12 hours, filter and take the filtrate, precipitate the filtrate in water, and dry for 24 hours to obtain terminal hydroxyl hyperbranched polyester ether; take 150 parts of isophorone diisocyanate, 90 parts of polyethylene glycol, 20 parts of terminal hydroxyl hyperbranched polyester ether, and 0.3 parts of dibutyltin dilaurate, stir evenly and heat to 85 ℃, keep the reaction at this temperature for 4 hours, add 30 parts of carbonyl iron powder, 10 parts of carbonyl nickel powder, and 1.5 parts of isocyanate silane coupling agent, keep stirring at 90℃ for 1 hour to obtain a modified additive; take polylactic acid particles, crush them, pass them through a 300-mesh sieve, and dry them in a vacuum oven at 60℃ for 12 hours to obtain polylactic acid powder; take 10 parts of the modified additive and 90 parts of polylactic acid powder, stir them evenly, melt blend them at 175℃ for 2 hours to obtain modified polylactic acid, and extrude them to obtain modified filaments with a fineness of 9tex;

[0029] S3: Wrapping the ultrafine metal wire with the modified filament, the preparation method is the same as that in Example 1, and obtaining the ultrafine electromagnetic shielding metal wire for textile use after wrapping.

[0030] Example 3: S1: Take a 5.5 mm round plate, cold-draw it at a speed of 70 m / min, pull the diameter from 5.5 mm to 2.3 mm, heat it to 1100 ° C, keep it at this temperature for 2 hours, after the heat preservation is completed, introduce nitrogen, cool it to room temperature at a speed of 150 ° C / h, cold-draw it at a speed of 70 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat it to 1100 ° C, keep it at this temperature for 1 hour, after the heat preservation is completed, introduce nitrogen, cool it to room temperature at a speed of 150 ° C / h, and then cold-draw it at a speed of 60 m / min. Cold drawing, pulling the diameter from 1.0 mm to 0.2 mm, heating to 1080 ° C, holding time for 2 hours, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a rate of 150 ° C / h, cold drawing at a speed of 60 m / min, pulling the diameter from 0.2 mm to 0.08 mm, cold drawing at a speed of 60 m / min, pulling the diameter from 0.08 mm to 0.03 mm, heating to 980 ° C, holding time for 6 hours, after the end of the heat preservation, passing nitrogen, cooling to room temperature at a rate of 150 ° C / h, to obtain ultrafine metal wire;

[0031] S2: Take 8 parts of 3,5-dihydroxybenzoic acid, 50 parts of potassium carbonate, 15 parts of 1,6-dibromohexane, and 80 parts of N,N-dimethylformamide, stir evenly, heat to 60°C for 12 hours, filter and take the filtrate, precipitate the filtrate in water, and dry for 24 hours to obtain terminal hydroxyl hyperbranched polyester ether; take 120 parts of isophorone diisocyanate, 70 parts of polyethylene glycol, 10 parts of terminal hydroxyl hyperbranched polyester ether, and 0.3 parts of dibutyltin dilaurate, stir evenly and heat to 85 ℃, keep the reaction at this temperature for 4 hours, add 35 parts of carbonyl iron powder, 8 parts of carbonyl nickel powder, and 1 part of isocyanate silane coupling agent, keep stirring at 90℃ for 1 hour to obtain a modified additive; take polylactic acid particles, crush them, pass them through a 300-mesh sieve, and dry them in a vacuum oven at 60℃ for 12 hours to obtain polylactic acid powder; take 20 parts of the modified additive and 80 parts of polylactic acid powder, stir them evenly, melt blend them at 175℃ for 2 hours to obtain modified polylactic acid, and extrude them to obtain modified filaments with a fineness of 9tex;

[0032] S3: Wrapping the ultrafine metal wire with the modified filament, the preparation method is the same as that in Example 1, and obtaining the ultrafine electromagnetic shielding metal wire for textile use after wrapping.

[0033] Comparative Example 1 (the ultrafine metal wire is not wrapped with the modified filament, and the other steps are consistent with Example 1): Take a 5.5 mm coil, cold draw it at a speed of 65 m / min, pull the diameter from 5.5 mm to 2.3 mm, heat it to 1100 ° C, keep it warm for 1 hour, after the end of the heat preservation, introduce nitrogen, cool it to room temperature at a speed of 150 ° C / h, cold draw it at a speed of 65 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat it to 1100 ° C, keep it warm for 1 hour, after the end of the heat preservation, introduce nitrogen, cool it to room temperature at a speed of 150 ° C / h, and then heat it to 65 m / min, cold drawing is carried out to reduce the diameter from 1.0 mm to 0.2 mm, heating to 1080°C, holding time is 2 h, after the holding is completed, nitrogen is introduced, cooling to room temperature at a rate of 150°C / h, cold drawing is carried out at a rate of 65 m / min, reducing the diameter from 0.2 mm to 0.08 mm, cold drawing is carried out at a rate of 65 m / min, reducing the diameter from 0.08 mm to 0.03 mm, heating to 980°C, holding time is 6 h, after the holding is completed, nitrogen is introduced, cooling to room temperature at a rate of 150°C / h, and obtaining ultrafine electromagnetic shielding metal wire for textile use.

[0034] Comparative Example 2 (using hydroxyl-terminated polydimethylsiloxane instead of terminal hydroxyl hyperbranched polyester ether, the remaining steps are consistent with Example 1): S1: Take a 5.5 mm round disc, cold draw at a speed of 65 m / min, pull the diameter from 5.5 mm to 2.3 mm, heat to 1100 ° C, hold for 1 h, after the end of the heat preservation, introduce nitrogen, cool to room temperature at a speed of 150 ° C / h, cold draw at a speed of 65 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat to 1100 ° C, hold for 1 h, after the end of the heat preservation, introduce nitrogen, cool to room temperature at a speed of 150 ° C / h, cold draw at a speed of 65 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat to 1100 ° C, hold for 1 h, after the end of the heat preservation, introduce nitrogen, cool to room temperature at a speed of 150 ° C / h Cool to room temperature, cold draw at a speed of 65m / min, pull the diameter from 1.0mm to 0.2mm, heat to 1080℃, keep warm for 2h, after the end of heat preservation, introduce nitrogen, cool to room temperature at a speed of 150℃ / h, cold draw at a speed of 65m / min, pull the diameter from 0.2mm to 0.08mm, cold draw at a speed of 65m / min, pull the diameter from 0.08mm to 0.03mm, heat to 980℃, keep warm for 6h, after the end of heat preservation, introduce nitrogen, cool to room temperature at a speed of 150℃ / h to obtain ultrafine metal wire;

[0035] S2: 130 parts of isophorone diisocyanate, 75 parts of polyethylene glycol, 15 parts of hydroxy di-terminated polydimethylsiloxane, and 0.3 parts of dibutyltin dilaurate were taken, stirred at a uniform speed and heated to 85°C, maintained at this temperature for 4 hours, 40 parts of carbonyl iron powder, 8 parts of carbonyl nickel powder, and 1.5 parts of isocyanate silane coupling agent were added, and stirred at 90°C for 1 hour to obtain a modified additive; polylactic acid particles were crushed, passed through a 300-mesh sieve, and dried in a vacuum oven at 60°C for 12 hours to obtain polylactic acid powder; 15 parts of the modified additive and 85 parts of the polylactic acid powder were taken, stirred evenly, and melt-blended at 175°C for 2 hours to obtain modified polylactic acid, which was extruded to obtain a modified filament with a fineness of 9 tex;

[0036] S3: Wrapping the ultrafine metal wire with the modified filament, the preparation method is the same as that in Example 1, and obtaining the ultrafine electromagnetic shielding metal wire for textile use after wrapping.

[0037] Comparative Example 3 (increasing the amount of the modifying additive, and the remaining method steps are consistent with Example 1): S1: Take a 5.5 mm round disc, cold draw it at a speed of 65 m / min, pull the diameter from 5.5 mm to 2.3 mm, heat it to 1100° C., keep it at this temperature for 1 hour, after the end of the heat preservation, introduce nitrogen, cool it to room temperature at a speed of 150° C. / h, cold draw it at a speed of 65 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat it to 1100° C., keep it at this temperature for 1 hour, after the end of the heat preservation, introduce nitrogen, cool it to room temperature at a speed of 150° C. / h, The wire was cold drawn at a speed of 65 m / min, and the diameter was pulled from 1.0 mm to 0.2 mm. The wire was heated to 1080°C and kept at this temperature for 2 h. After the end of the heat preservation, nitrogen was introduced and the wire was cooled to room temperature at a speed of 150°C / h. The wire was cold drawn at a speed of 65 m / min, and the diameter was pulled from 0.2 mm to 0.08 mm. The wire was cold drawn at a speed of 65 m / min, and the diameter was pulled from 0.08 mm to 0.03 mm. The wire was heated to 980°C and kept at this temperature for 6 h. After the end of the heat preservation, nitrogen was introduced and the wire was cooled to room temperature at a speed of 150°C / h to obtain an ultrafine metal wire.

[0038] S2: Take 12 parts of 3,5-dihydroxybenzoic acid, 55 parts of potassium carbonate, 18 parts of 1,6-dibromohexane, and 90 parts of N,N-dimethylformamide, stir evenly, heat to 60°C and react for 12 hours, filter and take the filtrate, precipitate the filtrate in water, and dry for 24 hours to obtain a terminal hydroxyl hyperbranched polyester ether; take 130 parts of isophorone diisocyanate, 75 parts of polyethylene glycol, 15 parts of terminal hydroxyl hyperbranched polyester ether, and 0.3 parts of dibutyltin dilaurate, stir evenly and heat to 85°C , keep the reaction at this temperature for 4 hours, add 50 parts of carbonyl iron powder, 20 parts of carbonyl nickel powder, and 1.5 parts of isocyanate silane coupling agent, keep stirring at 90°C for 1 hour to obtain the modified additive; take the polylactic acid particles, crush them, pass them through a 300-mesh sieve, and dry them in a vacuum oven at 60°C for 12 hours to obtain polylactic acid powder; take 25 parts of the modified additive and 75 parts of the polylactic acid powder, stir them evenly, melt blend them at 175°C for 2 hours to obtain modified polylactic acid, and extrude them to obtain modified filaments with a fineness of 9tex;

[0039] S3: Wrapping the ultrafine metal wire with the modified filament, the preparation method is the same as that in Example 1, and obtaining the ultrafine electromagnetic shielding metal wire for textile use after wrapping.

[0040] Comparative Example 4 (changing the amount of isophorone diisocyanate added, the other method steps are consistent with Example 1): S1: Take a 5.5 mm round disc, cold draw at a speed of 65 m / min, pull the diameter from 5.5 mm to 2.3 mm, heat to 1100 ° C, hold for 1 h, after the end of the heat preservation, pass nitrogen, cool to room temperature at a speed of 150 ° C / h, cold draw at a speed of 65 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat to 1100 ° C, hold for 1 h, after the end of the heat preservation, pass nitrogen, cool to room temperature at a speed of 150 ° C / h, cold draw at a speed of 65 m / min, pull the diameter from 2.3 mm to 1.0 mm, heat to 1100 ° C, hold for 1 h, after the end of the heat preservation, pass nitrogen, cool to room temperature at a speed of 150 ° C / h At room temperature, cold drawing is performed at a speed of 65 m / min, and the diameter is pulled from 1.0 mm to 0.2 mm. The temperature is raised to 1080°C and the heat preservation time is 2 hours. After the heat preservation is completed, nitrogen is introduced and the wire is cooled to room temperature at a speed of 150°C / h. The wire is cold drawn at a speed of 65 m / min, and the diameter is pulled from 0.2 mm to 0.08 mm. The wire is cold drawn at a speed of 65 m / min, and the diameter is pulled from 0.08 mm to 0.03 mm. The temperature is raised to 980°C and the heat preservation time is 6 hours. After the heat preservation is completed, nitrogen is introduced and the wire is cooled to room temperature at a speed of 150°C / h to obtain an ultrafine metal wire.

[0041] S2: Take 12 parts of 3,5-dihydroxybenzoic acid, 55 parts of potassium carbonate, 18 parts of 1,6-dibromohexane, and 90 parts of N,N-dimethylformamide, stir evenly, heat to 60°C for 12 hours, filter and take the filtrate, precipitate the filtrate in water, and dry for 24 hours to obtain terminal hydroxyl hyperbranched polyester ether; take 170 parts of isophorone diisocyanate, 75 parts of polyethylene glycol, 15 parts of terminal hydroxyl hyperbranched polyester ether, and 0.3 parts of dibutyltin dilaurate, stir evenly and heat to 85 ℃, keep the reaction at this temperature for 4 hours, add 40 parts of carbonyl iron powder, 8 parts of carbonyl nickel powder, and 1.5 parts of isocyanate silane coupling agent, keep stirring at 90℃ for 1 hour to obtain a modified additive; take polylactic acid particles, crush them, pass them through a 300-mesh sieve, and dry them in a vacuum oven at 60℃ for 12 hours to obtain polylactic acid powder; take 15 parts of the modified additive and 85 parts of polylactic acid powder, stir them evenly, melt blend them at 175℃ for 2 hours to obtain modified polylactic acid, and extrude them to obtain modified filaments with a fineness of 9tex;

[0042] S3: Wrapping the ultrafine metal wire with the modified filament, the preparation method is the same as that in Example 1, and obtaining the ultrafine electromagnetic shielding metal wire for textile use after wrapping.

[0043] Experiment: The ultrafine electromagnetic shielding metal wire for textiles prepared in Examples 1 to 3 and Comparative Examples 1 to 4 was blended in a ratio of 40% cotton, 30% polyester, and 30% ultrafine electromagnetic shielding metal wire for textiles to obtain a blended fabric (parameter: 23.5tex blended yarn). Referring to QJ2809-1996, the electromagnetic shielding capability of the blended fabric was tested at 100 and 500MHz; the modified polylactic acid prepared in Examples 1 to 3 and Comparative Examples 2 to 4 was extruded into a standard dumbbell-shaped mold for injection molding, and dried under vacuum at 60°C for 48 hours, and then its elongation at break was tested; the specific data are shown in the table below;

[0044]

[0045]

[0046] Conclusion: It can be seen from Comparative Example 1 that the electromagnetic shielding performance is reduced when the ultrafine metal wire is not wrapped with modified filaments, that is, carbonyl iron powder and carbonyl nickel powder are not added; in Comparative Example 2, hydroxyl double-terminated polydimethylsiloxane is used instead of terminal hydroxyl hyperbranched polyester ether, and the toughness of the modified polylactic acid obtained is not as good as that of the embodiment; in Comparative Example 3, the amount of modifying additive is increased, and the elongation at break is reduced instead; in Comparative Example 4, the amount of isophorone diisocyanate added is increased, and the elongation at break is significantly reduced. Excessive isophorone diisocyanate makes the cross-linking complicated and chaotic, which is more likely to break during the stretching process, affecting the mechanical properties.

[0047] In summary, the ultrafine electromagnetic shielding metal wire for textiles prepared by the present invention has good shielding ability against electromagnetic waves in various bands, is comfortable to use, and has an outer layer modified filament with good toughness and durability.

[0048] It should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for preparing ultrafine electromagnetic shielding metal wire for textile use, characterized in that: The following steps are involved: S1: Take the coil and make ultra-fine metal wire through multiple drawing and annealing processes; S2: Take 3,5-dihydroxybenzoic acid, potassium carbonate, 1,6-dibromohexane, and N,N-dimethylformamide, stir evenly, heat to 55-65°C, react for 10-15 hours, filter the filtrate, precipitate the filtrate in water, and dry for 20-28 hours to obtain a hydroxyl-terminated hyperbranched polyester ether; Isophorone diisocyanate, polyethylene glycol, terminal hydroxyl hyperbranched polyester ether, and dibutyltin dilaurate are stirred at a uniform speed and heated to 75-90°C, and the mixture is kept at this temperature for reaction for 3-4 hours. Carbonyl iron powder, carbonyl nickel powder, and isocyanate silane coupling agent are added, and the mixture is kept at 75-90°C and stirred for 1-2 hours to obtain a modified additive. Taking the modified additive and polylactic acid powder, stirring them evenly, melting and blending them, and extruding them to obtain modified filaments; S3: Wrapping the ultrafine metal wire with the modified filament to obtain the ultrafine electromagnetic shielding metal wire for textile use; The terminal hydroxyl hyperbranched polyester ether comprises the following raw materials, calculated by weight: 8 to 15 parts of 3,5-dihydroxybenzoic acid, 50 to 60 parts of potassium carbonate, 15 to 20 parts of 1,6-dibromohexane, and 80 to 100 parts of N,N-dimethylformamide; The modified additive comprises the following raw materials, calculated by mass: 120-150 parts of isophorone diisocyanate, 70-90 parts of polyethylene glycol, 10-20 parts of terminal hydroxyl hyperbranched polyester ether, 0.2-0.5 parts of dibutyltin dilaurate, 30-40 parts of carbonyl iron powder, 5-10 parts of carbonyl nickel powder, and 0.5-1.5 parts of isocyanate silane coupling agent; The modified filament comprises the following raw materials, calculated by mass: 10 to 20 parts of a modification additive and 80 to 90 parts of polylactic acid powder.

2. The method for preparing an ultrafine electromagnetic shielding metal wire for textile use according to claim 1, wherein: The preparation of the ultrafine metal wire comprises the following steps: Take 5.5mm coil, draw to 2-2.5mm, anneal at 1100℃, draw to 0.8-1.2mm, anneal at 1100℃, draw to 0.15-0.25mm, anneal at 1080℃, draw to 0.06-0.10mm, draw to 0.03mm, anneal at 980℃ to obtain ultrafine metal wire.

3. The method for preparing an ultrafine electromagnetic shielding metal wire for textile use according to claim 2, wherein: The specific preparation of the ultrafine metal wire includes the following steps: taking a 5.5 mm round coil, cold drawing it at a speed of 60-70 m / min, drawing the diameter from 5.5 mm to 2.3 mm, heating it to 1100° C., keeping it at this temperature for 1-2 hours, introducing nitrogen after the end of the heat preservation, cooling it to room temperature at a speed of 150° C. / h, cold drawing it at a speed of 60-70 m / min, drawing the diameter from 2.3 mm to 1.0 mm, heating it to 1100° C., keeping it at this temperature for 1-2 hours, introducing nitrogen after the end of the heat preservation, cooling it to room temperature at a speed of 150° C. / h, and cold drawing it at a speed of 60-70 m / min, drawing the diameter from 2.3 mm to 1.0 mm, heating it to 1100° C., keeping it at this temperature for 1-2 hours, and introducing nitrogen after the end of the heat preservation, cooling it to room temperature at a speed of 150° C. / h, and cold drawing it at a speed of 60-70 m / min, drawing the diameter from 2.3 mm to 1.0 mm, in, cold drawing is carried out at a speed of in, the diameter is pulled from 1.0mm to 0.2mm, the temperature is raised to 1080℃, the holding time is 1-2h, after the holding is completed, nitrogen is introduced, and it is cooled to room temperature at a speed of 150℃ / h, and cold drawing is carried out at a speed of 60-70m / min, the diameter is pulled from 0.2mm to 0.08mm, cold drawing is carried out at a speed of 60-70m / min, the diameter is pulled from 0.08mm to 0.03mm, the temperature is raised to 980℃, the holding time is 4-6h, after the holding is completed, nitrogen is introduced, and it is cooled to room temperature at a speed of 150℃ / h to obtain ultrafine metal wire.

4. The method for preparing an ultrafine electromagnetic shielding metal wire for textile use according to claim 1, wherein: The method for wrapping ultrafine metal wires with modified filaments comprises the following steps: blowroom carding, drawing, roving and spun yarn.

5. The method for preparing an ultrafine electromagnetic shielding metal wire for textile use according to claim 1, characterized in that: The preparation of the polylactic acid powder comprises the following steps: The polylactic acid particles were crushed, passed through a 300-mesh sieve, and dried in a vacuum oven at 55-65°C for 10-12 hours to obtain polylactic acid powder.

6. The ultrafine electromagnetic shielding metal wire for textile use obtained by the method for preparing the ultrafine electromagnetic shielding metal wire for textile use according to any one of claims 1 to 5.

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