Preparation of flexible multifunctional anti-radiation shielding polyester filament yarn

Abstract

The invention discloses preparation of flexible multifunctional anti-radiation shielding polyester filament yarn, and relates to the technical field of polyester. A ceramic filler precursor is prepared through electrostatic spinning, and nano lignin, polysilazane and aluminum oxide are used. A precursor is pretreated before calcination, carbides are formed through hot pressing, and meanwhile, a compact and continuous physical barrier can be formed in the shielding filler by means of the continuity of fibers and the cross-linking effect between the fibers. After high-temperature pyrolysis, lignin is converted into amorphous carbon, silicon carbide and silicon nitride ceramic grains are wrapped, a filler containing Si, Al and N is formed, radiation is effectively attenuated, and the shielding effect is enhanced. In addition, through combined use of the silane coupling agent and the compatilizer, the dispersity of the filler in the polyester chips is improved, the high-content polyester master batch is prepared, and the radiation shielding performance of the polyester fiber is further enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of polyester, in particular to the preparation of flexible multifunctional radiation-resistant shielding polyester filaments. Background Art

[0002] With the rapid development of electronic information technology and nuclear energy applications, the protection against electromagnetic and ionizing radiation has become increasingly prominent, affecting a number of key areas, including national defense, aerospace, medical protection, precision electronic equipment, and special occupational protection. The development of composite fiber materials that combine high-efficiency shielding performance with good flexibility, wear comfort, and processability is of great significance.

[0003] As a widely used synthetic fiber with superior performance, polyester offers advantages such as high strength, good chemical resistance, and ease of processing into various textile forms, making it an ideal substrate for flexible protective fabrics. However, traditional radiation-resistant modification methods have the following limitations:

[0004] 1. Shielding efficiency bottleneck: Early radiation-resistant polyester products mostly relied on the addition of single metal powders or conductive materials. These materials only achieved a certain shielding effect when added in large doses, but this made fiber spinning difficult, significantly reduced flexibility, increased density, and deteriorated the feel. Furthermore, metal materials were susceptible to corrosion, and conductive materials were prone to short-circuiting and agglomerating during the spinning process, making it difficult to achieve an efficient, stable, and uniform shielding layer.

[0005] 2. Filler dispersion and compatibility issues: To achieve effective radiation attenuation, high levels of shielding fillers are often required in the polyester matrix. However, the polarity differences between inorganic or ceramic fillers and the organic polyester matrix result in poor interfacial compatibility and agglomeration. Even with conventional dispersing coupling agents, achieving uniform dispersion at high filler loadings is difficult, which not only reduces shielding efficiency but also severely impacts the stability of the spinning process and the mechanical properties of the fiber.

[0006] Therefore, there is an urgent need in this field to develop a new type of flexible multifunctional radiation-resistant shielding polyester filament and a preparation method thereof. Summary of the Invention

[0007] The purpose of the present invention is to provide a method for preparing a flexible multifunctional radiation-resistant shielding polyester filament to solve the problems existing in the prior art.

[0008] In order to solve the above technical problems, the present invention provides the following technical solution: a preparation method of a flexible multifunctional radiation-resistant shielding polyester filament, comprising the following preparation steps:

[0009] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:(0.8-1.5):(4-8) to obtain a mixed solution; lignin dispersion, nano-alumina sol, and the mixed solution are mixed in a mass ratio of 3:1:5-9, stirred for 3 hours, ultrasonically eliminated bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 1-20 μm to obtain an anti-radiation shielding filler;

[0010] (2) Mixing the anti-radiation shielding filler, silane coupling agent, and pure water in a mass ratio of 1:0.5-1:1.5-2.5, adjusting the pH to 3.0-3.9, grinding for 20-30 minutes, adding 0.5 times the mass of the anti-radiation shielding filler polymethyl methacrylate emulsion, grinding for 5-10 minutes, drying, and crushing to 50-80 μm to obtain the filler;

[0011] (4) Take 50-65 parts of PET polyester chips, 30-40 parts of fillers, 3-15 parts of compatibilizers, and 0.05-1.0 parts of antioxidants by weight, and put the other ingredients except the fillers into the tail feeding port of the twin-screw extruder, and the fillers enter from the middle feeding port of the twin-screw extruder. After extrusion, granulation is performed to obtain a masterbatch. The temperature of the twin-screw extruder is 250-280°C, the screw speed is 100-160rpm, and the extrusion pressure is 100-170kgf / cm 3 ;

[0012] (5) According to the weight ratio, 60-80 parts of PET polyester chips, 25-40 parts of masterbatch, 10-20 parts of polylactic acid fiber powder, and 2-5 parts of compatibilizer are taken and melt-spun. The spinning metering pump supply is 750g / min, the spinning temperature is 290℃, the spinning speed is 750m / min, the drafting multiple is 3.5 times, the crimping pressure is 0.3Mpa, and the crimping degree is 3.5% to obtain flexible multifunctional radiation-resistant shielding polyester filament.

[0013] Furthermore, in step (1), polysilazane was purchased from Kion Corporation of the United States with a brand name of VL20 and a number average molecular weight of 560; PVP was purchased from Sigma with a molecular weight of 4000; and the nano-alumina sol was a product produced by Hefei Xiangzheng Chemical Technology Co., Ltd. with a mass concentration of 20-25% and a particle size of 10-20 nm.

[0014] Furthermore, the lignin dispersion in step (1) is composed of nano-lignin, N,N-dimethylformamide, and KH-550 in a mass ratio of 1:15:0.02.

[0015] Furthermore, the particle size of the nano-lignin is 10 to 50 nm.

[0016] Furthermore, the spinning in step (1) is electrostatic spinning, and its process parameters are: voltage of 15 to 20 kV, receiving distance of 8 to 17 cm, and spinning rate of 0.1 to 0.5 m / s.

[0017] Furthermore, in step (1), the hot pressing temperature is 120-160° C., the pressure is 0.9-2 MPa, and the time is 1-4 h.

[0018] Furthermore, the specific method of calcination in step (1) is: first treat at 250°C for 2 hours to remove the solvent and low molecular weight organic matter, then introduce nitrogen at 0.06L / min, increase the temperature to 600°C at 5°C / min, keep warm for 1 hour, then introduce argon and ammonia, increase the temperature to 850°C at 10°C / min, and keep warm for 2 to 4 hours.

[0019] Furthermore, the volume ratio of the argon gas to the ammonia gas is 1:1.

[0020] Furthermore, in step (2), the silane coupling agent is at least one of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, glycidoxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethoxysilane and N-β(aminoethyl)-γ-aminopropylmethyldimethoxysilane.

[0021] Furthermore, the compatibilizer is prepared by mixing maleic anhydride grafted EVA and maleic anhydride grafted HDPE in a mass ratio of 1-2:0.5-1.2.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The present invention utilizes nano-lignin, polysilazane, and alumina to prepare a ceramic filler precursor through electrospinning. Before the calcination process, the precursor is pretreated. Under hot pressing, molten carbide is formed by lignin, and the cross-contact points between the fibers are cross-linked. High pressure forces the molten lignin to penetrate each other. The connecting effect of lignin carbon is utilized to form a strong and continuous physical barrier inside the entire filler. Then, under high-temperature pyrolysis, the remaining carbon skeleton of lignin is converted into amorphous carbon, which wraps the silicon carbide and silicon nitride ceramic grains generated by polysilazane, forming a filler with effective shielding elements Si, Al, and N embedded in the high-C element. The synergistic effect between the elements effectively attenuates radiation and enhances the shielding effect of the material. At the same time, the continuity inside the material ensures that the radiation can continuously interact with the effective shielding material during the penetration process, and there is no short-circuit path that is easy to penetrate.

[0024] (2) The present invention uses a silane coupling agent and a compatibilizer in combination, and finds that the two can synergistically improve the dispersion effect of the anti-radiation shielding filler in the polyester chips, thereby obtaining a high-content polyester masterbatch, further enhancing the anti-radiation shielding effect of the polyester fiber. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] In order to more clearly illustrate the method provided by the present invention, the following examples are described in detail. In the following examples, the conventional weaving method is used to weave the 180g / m 2 The fabrics are tested, and the test methods for each index are as follows:

[0027] Electromagnetic radiation protection performance test method: According to the measurement method of shielding effectiveness of electromagnetic shielding room GB / T12190-2021, the shielding effectiveness of the fabrics in the embodiment and comparative example were tested in the frequency range of 150 MHz to 18 GHz.

[0028] X-ray shielding performance test method: Under the condition that the geometric center of the ray emitter and the center of the detector remain unchanged, the air kerma rate (H0) without shielding material is obtained, and then shielding material is placed between the radiation source and the detector to obtain the air kerma rate (H) with shielding material. The X-ray shielding rate η of the fabric is calculated according to η = [1-(H / H0)] * 100%.

[0029] Example 1

[0030] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:0.8:4 to obtain a mixed solution; lignin dispersion, nano-alumina sol, and the mixed solution are mixed in a mass ratio of 3:1:5, stirred at 100 rpm for 3 hours, ultrasonicated at 40 kHz for 30 minutes to eliminate bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 1 μm to obtain an anti-radiation shielding filler; the lignin dispersion is composed of nano-lignin with a particle size of 10 nm, N, N-dimethylformamide, and KH-550 in a mass ratio of 1:15:0.02; the spinning is The electrospinning process parameters are as follows: voltage of 15 kV, receiving distance of 15 cm, spinning rate of 0.3 m / s; the hot pressing temperature is 120° C., pressure of 0.9 MPa, and time is 1 hour; the specific calcination method is as follows: first, treatment at 250° C. for 2 hours to remove solvent and low molecular weight organic matter, then nitrogen is introduced at 0.06 L / min, the temperature is increased at 5° C. / min to 600° C., and the temperature is maintained for 1 hour, then argon and ammonia are introduced, the temperature is increased at 10° C. / min to 850° C., and the temperature is maintained for 2 hours; the volume ratio of argon to ammonia is 1:1;

[0031] (2) 0.5 g of polyvinyl alcohol powder was added to 100 mL of water and heated to 65° C. to dissolve the polyvinyl alcohol completely, thereby obtaining a polyvinyl alcohol aqueous solution with a mass percentage concentration of 0.5%; then, an emulsifier, sodium lauryl sulfate (the amount of which was 8% of the mass of the methyl methacrylate monomer) and 45 mL of methyl methacrylate monomer were added to the polyvinyl alcohol aqueous solution in sequence, and the resulting mixture was heated to 80° C., and 1.5 mL of ammonium persulfate solution with a concentration of 1 mol / L was added dropwise to the reaction system under stirring at 300 rpm. After the addition was complete, the reaction was continued at 80° C. with stirring for 6 h to obtain a polymethyl methacrylate emulsion;

[0032] (3) Mixing the anti-radiation shielding filler, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and pure water in a mass ratio of 1:0.5:1.5, adjusting the pH to 3.0 with acetic acid, grinding at 500 rpm for 20 min, adding 0.5 times the mass of the anti-radiation shielding filler polymethyl methacrylate emulsion, grinding at 500 rpm for 5-10 min, drying, and crushing to 50-80 μm to obtain the filler;

[0033] (4) According to weight, 50 parts of PET polyester chips, 30 parts of fillers, 3 parts of compatibilizers, and 0.05 parts of antioxidants were taken, and the other ingredients except the fillers were fed into the tail feeding port of the twin-screw extruder, and the fillers were fed into the middle feeding port of the twin-screw extruder. After extrusion, granulation was performed to obtain a masterbatch; the antioxidant used was a compound system of antioxidants 1010 and 168, with a mass ratio of 1:2;

[0034] (5) By weight, 60 parts of PET polyester chips, 25 parts of masterbatch, 10 parts of polylactic acid fiber powder, and 2 parts of compatibilizer were melt-spun to obtain flexible multifunctional radiation-resistant shielding polyester filaments.

[0035] Example 2

[0036] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:0.8:4 to obtain a mixed solution; lignin dispersion, nano-alumina sol, and the mixed solution are mixed in a mass ratio of 3:1:5, stirred at 100 rpm for 3 hours, ultrasonicated at 40 kHz for 30 minutes to eliminate bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 1 μm to obtain an anti-radiation shielding filler; the lignin dispersion is composed of nano-lignin with a particle size of 10 nm, N, N-dimethylformamide, and KH-550 in a mass ratio of 1:15:0.02; the spinning is The electrospinning process parameters are as follows: voltage of 15 kV, receiving distance of 15 cm, spinning rate of 0.3 m / s; the hot pressing temperature is 120° C., pressure of 0.9 MPa, and time is 1 hour; the specific calcination method is as follows: first, treatment at 250° C. for 2 hours to remove solvent and low molecular weight organic matter, then nitrogen is introduced at 0.06 L / min, the temperature is increased at 5° C. / min to 600° C., and the temperature is maintained for 1 hour, then argon and ammonia are introduced, the temperature is increased at 10° C. / min to 850° C., and the temperature is maintained for 2 hours; the volume ratio of argon to ammonia is 1:1;

[0037] (2) 0.5 g of polyvinyl alcohol powder was added to 100 mL of water and heated to 65° C. to dissolve the polyvinyl alcohol completely, thereby obtaining a polyvinyl alcohol aqueous solution with a mass percentage concentration of 0.5%; then, an emulsifier, sodium lauryl sulfate (the amount of which was 8% of the mass of the methyl methacrylate monomer) and 45 mL of methyl methacrylate monomer were added to the polyvinyl alcohol aqueous solution in sequence, and the resulting mixture was heated to 80° C., and 1.5 mL of ammonium persulfate solution with a concentration of 1 mol / L was added dropwise to the reaction system under stirring at 300 rpm. After the addition was complete, the reaction was continued at 80° C. with stirring for 6 h to obtain a polymethyl methacrylate emulsion;

[0038] (3) Mixing the anti-radiation shielding filler, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, and pure water in a mass ratio of 1:0.6:1.5, adjusting the pH to 3.0 with acetic acid, grinding at 500 rpm for 20 min, adding 0.5 times the mass of the anti-radiation shielding filler polymethyl methacrylate emulsion, grinding at 500 rpm for 5 min, drying, and crushing to 50 μm to obtain the filler;

[0039] (4) According to weight, 55 parts of PET polyester chips, 30 parts of fillers, 3 parts of compatibilizers, and 0.05 parts of antioxidants were taken, and the other ingredients except the fillers were fed into the tail feeding port of the twin-screw extruder, and the fillers were fed into the middle feeding port of the twin-screw extruder. After extrusion, granulation was performed to obtain a masterbatch; the antioxidant used was a compound system of antioxidants 1010 and 168, with a mass ratio of 1:2;

[0040] (5) By weight, 67 parts of PET polyester chips, 25 parts of masterbatch, 13 parts of polylactic acid fiber powder, and 2 parts of compatibilizer were melt-spun to obtain flexible multifunctional radiation-resistant shielding polyester filaments.

[0041] Example 3

[0042] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:1.1:6 to obtain a mixed solution; lignin dispersion, nano-alumina sol, and the mixed solution are mixed in a mass ratio of 3:1:7, stirred at 100 rpm for 3 hours, ultrasonicated at 40 kHz for 30 minutes to eliminate bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 10 μm to obtain an anti-radiation shielding filler; the lignin dispersion is composed of nano-lignin with a particle size of 30 nm, N, N-dimethylformamide, and KH-550 in a mass ratio of 1:15:0.02; the spinning is The electrospinning process parameters are as follows: voltage of 15 kV, receiving distance of 15 cm, spinning rate of 0.3 m / s; the hot pressing temperature is 140°C, pressure is 1.5 MPa, and time is 2 hours; the specific calcination method is as follows: first, treatment at 250°C for 2 hours to remove solvent and low molecular weight organic matter, then nitrogen is introduced at 0.06 L / min, the temperature is increased at 5°C / min to 600°C, and the temperature is maintained for 1 hour, then argon and ammonia are introduced, the temperature is increased at 10°C / min to 850°C, and the temperature is maintained for 3 hours; the volume ratio of argon to ammonia is 1:1;

[0043] (2) 0.5 g of polyvinyl alcohol powder was added to 100 mL of water and heated to 65° C. to dissolve the polyvinyl alcohol completely, thereby obtaining a polyvinyl alcohol aqueous solution with a mass percentage concentration of 0.5%; then, an emulsifier, sodium lauryl sulfate (the amount of which was 8% of the mass of the methyl methacrylate monomer) and 45 mL of methyl methacrylate monomer were added to the polyvinyl alcohol aqueous solution in sequence, and the resulting mixture was heated to 80° C., and 1.5 mL of ammonium persulfate solution with a concentration of 1 mol / L was added dropwise to the reaction system under stirring at 300 rpm. After the addition was complete, the reaction was continued at 80° C. with stirring for 6 h to obtain a polymethyl methacrylate emulsion;

[0044] (3) Mixing the anti-radiation shielding filler, γ-aminopropyltrimethoxysilane, and pure water in a mass ratio of 1:0.7:2, adjusting the pH to 3.5 with acetic acid, grinding at 500 rpm for 25 min, adding a polymethyl methacrylate emulsion 0.5 times the mass of the anti-radiation shielding filler, grinding at 500 rpm for 8 min, drying, and crushing to 65 μm to obtain the filler;

[0045] (4) According to weight, 57 parts of PET polyester chips, 35 parts of fillers, 5 parts of compatibilizers, and 0.1 parts of antioxidants were taken, and the other ingredients except the fillers were fed into the tail feeding port of the twin-screw extruder, and the fillers were fed into the middle feeding port of the twin-screw extruder. After extrusion, granulation was performed to obtain a masterbatch; the antioxidant used was a compound system of antioxidants 1010 and 168, with a mass ratio of 1:2;

[0046] (5) According to weight, 70 parts of PET polyester chips, 30 parts of masterbatch, 10 parts of polylactic acid fiber powder, and 3 parts of compatibilizer were melt-spun to obtain flexible multifunctional radiation-resistant shielding polyester filaments.

[0047] Example 4

[0048] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:1.1:6 to obtain a mixed solution; lignin dispersion, nano-alumina sol, and the mixed solution are mixed in a mass ratio of 3:1:7, stirred at 100 rpm for 3 hours, ultrasonicated at 40 kHz for 30 minutes to eliminate bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 10 μm to obtain an anti-radiation shielding filler; the lignin dispersion is composed of nano-lignin with a particle size of 30 nm, N, N-dimethylformamide, and KH-550 in a mass ratio of 1:15:0.02; the spinning is The electrospinning process parameters are as follows: voltage of 15 kV, receiving distance of 15 cm, spinning rate of 0.3 m / s; the hot pressing temperature is 140°C, pressure is 1.5 MPa, and time is 3 hours; the specific calcination method is as follows: first, treatment at 250°C for 2 hours to remove solvent and low molecular weight organic matter, then nitrogen is introduced at 0.06 L / min, the temperature is increased at 5°C / min to 600°C, and the temperature is maintained for 1 hour, then argon and ammonia are introduced, the temperature is increased at 10°C / min to 850°C, and the temperature is maintained for 3 hours; the volume ratio of argon to ammonia is 1:1;

[0049] (2) 0.5 g of polyvinyl alcohol powder was added to 100 mL of water and heated to 65° C. to dissolve the polyvinyl alcohol completely, thereby obtaining a polyvinyl alcohol aqueous solution with a mass percentage concentration of 0.5%; then, an emulsifier, sodium lauryl sulfate (the amount of which was 8% of the mass of the methyl methacrylate monomer) and 45 mL of methyl methacrylate monomer were added to the polyvinyl alcohol aqueous solution in sequence, and the resulting mixture was heated to 80° C., and 1.5 mL of ammonium persulfate solution with a concentration of 1 mol / L was added dropwise to the reaction system under stirring at 300 rpm. After the addition was complete, the reaction was continued at 80° C. with stirring for 6 h to obtain a polymethyl methacrylate emulsion;

[0050] (3) Mixing the anti-radiation shielding filler, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, and pure water in a mass ratio of 1:0.8:2, adjusting the pH to 3.5 with acetic acid, grinding at 500 rpm for 25 min, adding polymethyl methacrylate emulsion 0.5 times the mass of the anti-radiation shielding filler, grinding at 500 rpm for 8 min, drying, and crushing to 65 μm to obtain the filler;

[0051] (4) According to weight, 61 parts of PET polyester chips, 38 parts of fillers, 7 parts of compatibilizers, and 1.0 parts of antioxidants were taken, and the other ingredients except the fillers were fed into the tail feeding port of the twin-screw extruder, and the fillers were fed into the middle feeding port of the twin-screw extruder. After extrusion, granulation was performed to obtain a masterbatch; the antioxidant used was a compound system of antioxidants 1010 and 168, with a mass ratio of 1:2;

[0052] (5) By weight, 67 parts of PET polyester chips, 38 parts of masterbatch, 15 parts of polylactic acid fiber powder, and 5 parts of compatibilizer were melt-spun to obtain flexible multifunctional radiation-resistant shielding polyester filaments.

[0053] Example 5

[0054] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:1.5:8 to obtain a mixed liquid; lignin dispersion, nano-alumina sol, and the mixed liquid are mixed in a mass ratio of 3:1:9, stirred at 100 rpm for 3 hours, and ultrasonicated at 40 kHz for 30 minutes to eliminate bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 20 μm to obtain an anti-radiation shielding filler; the lignin dispersion is composed of nano-lignin with a particle size of 50 nm, N, N-dimethylformamide, and KH-550 in a mass ratio of 1:15:0.02; the spinning The electrospinning process parameters are as follows: voltage of 15 kV, receiving distance of 15 cm, spinning rate of 0.3 m / s; the hot pressing temperature is 160° C., pressure of 2 MPa, and time of 4 hours; the specific calcination method is as follows: first, treatment at 250° C. for 2 hours to remove solvent and low molecular weight organic matter, then nitrogen is introduced at 0.06 L / min, the temperature is increased at 5° C. / min to 600° C., and the temperature is kept at this temperature for 1 hour, and then argon and ammonia are introduced at 10° C. / min to 850° C., and the temperature is kept at this temperature for 4 hours; the volume ratio of argon to ammonia is 1:1;

[0055] (2) 0.5 g of polyvinyl alcohol powder was added to 100 mL of water and heated to 65° C. to dissolve the polyvinyl alcohol completely, thereby obtaining a polyvinyl alcohol aqueous solution with a mass percentage concentration of 0.5%; then, an emulsifier, sodium lauryl sulfate (the amount of which was 8% of the mass of the methyl methacrylate monomer) and 45 mL of methyl methacrylate monomer were added to the polyvinyl alcohol aqueous solution in sequence, and the resulting mixture was heated to 80° C., and 1.5 mL of ammonium persulfate solution with a concentration of 1 mol / L was added dropwise to the reaction system under stirring at 300 rpm. After the addition was complete, the reaction was continued at 80° C. with stirring for 6 h to obtain a polymethyl methacrylate emulsion;

[0056] (3) Mixing the anti-radiation shielding filler, γ-aminopropyltriethoxysilane, and pure water in a mass ratio of 1:1:2.5, adjusting the pH to 3.9 with acetic acid, grinding at 500 rpm for 30 min, adding a polymethyl methacrylate emulsion 0.5 times the mass of the anti-radiation shielding filler, grinding at 500 rpm for 10 min, drying, and crushing to 80 μm to obtain the filler;

[0057] (4) According to weight, 65 parts of PET polyester chips, 40 parts of fillers, 15 parts of compatibilizers, and 1.0 parts of antioxidants were taken, and the other ingredients except the fillers were fed into the tail feeding port of the twin-screw extruder, and the fillers were fed into the middle feeding port of the twin-screw extruder. After extrusion, granulation was performed to obtain a masterbatch; the antioxidant used was a compound system of antioxidants 1010 and 168, with a mass ratio of 1:2;

[0058] (5) By weight, 80 parts of PET polyester chips, 40 parts of masterbatch, 20 parts of polylactic acid fiber powder, and 5 parts of compatibilizer were melt-spun to obtain flexible multifunctional radiation-resistant shielding polyester filaments.

[0059] Comparative Example 1 (without lignin)

[0060] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:1.5:8 to obtain a mixed solution; nano-alumina sol and the mixed solution are mixed in a mass ratio of 1:9, stirred at 100 rpm for 3 hours, and ultrasonicated at 40 kHz for 30 minutes to eliminate bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 20 μm to obtain an anti-radiation shielding filler; the spinning is electrostatic spinning, and its process parameters are: voltage 15 kV, receiving distance 15 cm, spinning The speed is 0.3 m / s; the hot pressing temperature is 160°C, the pressure is 2 MPa, and the time is 4 hours; the specific method of the calcination is: first, treat at 250°C for 2 hours to remove the solvent and low-molecular-weight organic matter, then introduce nitrogen at 0.06 L / min, increase the temperature to 600°C at 5°C / min, and keep it at that temperature for 1 hour, then introduce argon and ammonia, increase the temperature to 850°C at 10°C / min, and keep it at that temperature for 4 hours; the volume ratio of argon to ammonia is 1:1;

[0061] (2) 0.5 g of polyvinyl alcohol powder was added to 100 mL of water and heated to 65° C. to dissolve the polyvinyl alcohol completely, thereby obtaining a polyvinyl alcohol aqueous solution with a mass percentage concentration of 0.5%; then, an emulsifier, sodium lauryl sulfate (the amount of which was 8% of the mass of the methyl methacrylate monomer) and 45 mL of methyl methacrylate monomer were added to the polyvinyl alcohol aqueous solution in sequence, and the resulting mixture was heated to 80° C., and 1.5 mL of ammonium persulfate solution with a concentration of 1 mol / L was added dropwise to the reaction system under stirring at 300 rpm. After the addition was complete, the reaction was continued at 80° C. with stirring for 6 h to obtain a polymethyl methacrylate emulsion;

[0062] (3) Mixing the anti-radiation shielding filler, γ-aminopropyltriethoxysilane, and pure water in a mass ratio of 1:1:2.5, adjusting the pH to 3.9 with acetic acid, grinding at 500 rpm for 30 min, adding a polymethyl methacrylate emulsion 0.5 times the mass of the anti-radiation shielding filler, grinding at 500 rpm for 10 min, drying, and crushing to 80 μm to obtain the filler;

[0063] (4) According to weight, 65 parts of PET polyester chips, 40 parts of fillers, 15 parts of compatibilizers, and 1.0 parts of antioxidants were taken, and the other ingredients except the fillers were fed into the tail feeding port of the twin-screw extruder, and the fillers were fed into the middle feeding port of the twin-screw extruder. After extrusion, granulation was performed to obtain a masterbatch; the antioxidant used was a compound system of antioxidants 1010 and 168, with a mass ratio of 1:2;

[0064] (5) By weight, 80 parts of PET polyester chips, 40 parts of masterbatch, 20 parts of polylactic acid fiber powder, and 5 parts of compatibilizer were melt-spun to obtain flexible multifunctional radiation-resistant shielding polyester filaments.

[0065] Comparative Example 2 (without aluminum sol)

[0066] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:1.5:8 to obtain a mixed liquid; the lignin dispersion and the mixed liquid are mixed in a mass ratio of 3:9, stirred at 100 rpm for 3 hours, and ultrasonicated at 40 kHz for 30 minutes to eliminate bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 20 μm to obtain an anti-radiation shielding filler; the lignin dispersion is composed of nano-lignin with a particle size of 50 nm, N,N-dimethylformamide, and KH-550, and the mass ratio is 1:15:0.02; the spinning is electrostatic spinning The process parameters are as follows: voltage of 15 kV, receiving distance of 15 cm, spinning speed of 0.3 m / s; the hot pressing temperature is 160°C, pressure is 2 MPa, and time is 4 hours; the specific calcination method is as follows: first, treatment at 250°C for 2 hours to remove solvents and low-molecular-weight organic matter, then nitrogen is introduced at 0.06 L / min, the temperature is increased at 5°C / min to 600°C, and the temperature is kept at this temperature for 1 hour, then argon and ammonia are introduced, the temperature is increased at 10°C / min to 850°C, and the temperature is kept at this temperature for 4 hours; the volume ratio of argon to ammonia is 1:1;

[0067] (2) 0.5 g of polyvinyl alcohol powder was added to 100 mL of water and heated to 65° C. to dissolve the polyvinyl alcohol completely, thereby obtaining a polyvinyl alcohol aqueous solution with a mass percentage concentration of 0.5%; then, an emulsifier, sodium lauryl sulfate (the amount of which was 8% of the mass of the methyl methacrylate monomer) and 45 mL of methyl methacrylate monomer were added to the polyvinyl alcohol aqueous solution in sequence, and the resulting mixture was heated to 80° C., and 1.5 mL of ammonium persulfate solution with a concentration of 1 mol / L was added dropwise to the reaction system under stirring at 300 rpm. After the addition was complete, the reaction was continued at 80° C. with stirring for 6 h to obtain a polymethyl methacrylate emulsion;

[0068] (3) Mixing the anti-radiation shielding filler, γ-aminopropyltriethoxysilane, and pure water in a mass ratio of 1:1:2.5, adjusting the pH to 3.9 with acetic acid, grinding at 500 rpm for 30 min, adding a polymethyl methacrylate emulsion 0.5 times the mass of the anti-radiation shielding filler, grinding at 500 rpm for 10 min, drying, and crushing to 80 μm to obtain the filler;

[0069] (4) According to weight, 65 parts of PET polyester chips, 40 parts of fillers, 15 parts of compatibilizers, and 1.0 parts of antioxidants were taken, and the other ingredients except the fillers were fed into the tail feeding port of the twin-screw extruder, and the fillers were fed into the middle feeding port of the twin-screw extruder. After extrusion, granulation was performed to obtain a masterbatch; the antioxidant used was a compound system of antioxidants 1010 and 168, with a mass ratio of 1:2;

[0070] (5) By weight, 80 parts of PET polyester chips, 40 parts of masterbatch, 20 parts of polylactic acid fiber powder, and 5 parts of compatibilizer were melt-spun to obtain flexible multifunctional radiation-resistant shielding polyester filaments.

[0071] Comparative Example 3

[0072] The difference between Comparative Example 3 and Example 5 is that multilayer graphene is used instead of the anti-radiation shielding filler, and the remaining steps are the same as Example 5.

[0073] Comparative Example 4

[0074] The difference between Comparative Example 4 and Example 5 is that boron carbide is used instead of the radiation-resistant shielding filler, and the remaining steps are the same as Example 5.

[0075] Comparative Example 5

[0076] (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1:1.5:8 to obtain a mixed liquid; the lignin dispersion and the mixed liquid are mixed in a mass ratio of 3:9, stirred at 100 rpm for 3 hours, and ultrasonicated at 40 kHz for 30 minutes to eliminate bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 20 μm to obtain an anti-radiation shielding filler; the lignin dispersion is composed of nano-lignin with a particle size of 50 nm, N,N-dimethylformamide, and KH-550, and the mass ratio is 1:15:0.02; the spinning is electrostatic spinning The process parameters are as follows: voltage of 15 kV, receiving distance of 15 cm, spinning speed of 0.3 m / s; the hot pressing temperature is 160°C, pressure is 2 MPa, and time is 4 hours; the specific calcination method is as follows: first, treatment at 250°C for 2 hours to remove solvents and low-molecular-weight organic matter, then nitrogen is introduced at 0.06 L / min, the temperature is increased at 5°C / min to 600°C, and the temperature is kept at this temperature for 1 hour, then argon and ammonia are introduced, the temperature is increased at 10°C / min to 850°C, and the temperature is kept at this temperature for 4 hours; the volume ratio of argon to ammonia is 1:1;

[0077] (2) By weight, 80 parts of PET polyester chips, 10 parts of anti-radiation shielding filler, 20 parts of polylactic acid fiber powder, and 5 parts of compatibilizer were melt-spun to obtain flexible multifunctional anti-radiation shielding polyester filaments.

[0078] Effect Examples

[0079] Table 1 below shows the performance analysis results of the polyester filaments of Examples 1 to 5 of the present invention and Comparative Examples 1 to 5.

[0080] Table 1

[0081] X-ray shielding performance (%) Electromagnetic radiation protection performance (dB) Example 1 99.9 37.72 Example 2 99.9 39.67 Example 3 99.9 38.66 Example 4 99.9 40.88 Example 5 99.9 40.12 Comparative Example 1 81.95 31.35 Comparative Example 2 90.92 34.56 Comparative Example 3 92.85 35.08 Comparative Example 4 90.46 33.78 Comparative Example 5 89.43 33.29

[0082] The present invention prepares a ceramic filler precursor by electrospinning, using nano-lignin, polysilazane and aluminum oxide. The precursor is pretreated before calcination and formed into a carbide by hot pressing. At the same time, relying on the continuity of the fibers and the cross-linking effect between the fibers, a dense and continuous physical barrier can be formed inside the shielding filler. After high-temperature pyrolysis, the lignin is converted into amorphous carbon, which encapsulates silicon carbide and silicon nitride ceramic grains to form a filler containing Si, Al and N, which effectively attenuates radiation and enhances the shielding effect. In addition, the combined use of a silane coupling agent and a compatibilizer improves the dispersibility of the filler in the polyester slice, produces a high-content polyester masterbatch, and further enhances the radiation shielding performance of the polyester fiber.

[0083] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed therein. Any reference in a claim should not be construed as limiting the claim to which it relates.

Claims

1. Preparation of a flexible multifunctional radiation-resistant shielding polyester filament, characterized in that: The method comprises the following preparation steps: (1) Polysilazane, polyvinyl pyrrolidone, and ethanol are mixed in a mass ratio of 1: (0.8-1.5): (4-8) to obtain a mixed solution; lignin dispersion, nano-alumina sol, and the mixed solution are mixed in a mass ratio of 3:1:5-9, stirred for 3 hours, ultrasonically eliminated bubbles, and then spun, hot-pressed, calcined, and crushed to a particle size of 1-20 μm to obtain an anti-radiation shielding filler; (2) Mix the anti-radiation shielding filler, silane coupling agent and pure water in a mass ratio of 1:0.5-1:1.5-2.5, adjust the pH to 3.0-3.9, grind for 20-30 minutes, add polymethyl methacrylate emulsion 0.5 times the mass of the anti-radiation shielding filler, grind for 5-10 minutes, dry and crush to 50-80 μm to obtain the filler; (4) Take 50-65 parts of PET polyester chips, 30-40 parts of fillers, 3-15 parts of compatibilizers, and 0.05-1.0 parts of antioxidants by weight, and put the other ingredients except the fillers into the tail feeding port of the twin-screw extruder, and the fillers into the middle feeding port of the twin-screw extruder. After extrusion, granulation is performed to obtain a masterbatch; (5) By weight, 60-80 parts of PET polyester chips, 25-40 parts of masterbatch, 10-20 parts of polylactic acid fiber powder, and 2-5 parts of compatibilizer are melt-spun to obtain flexible multifunctional radiation-resistant shielding polyester filaments.

2. The preparation method of a flexible multifunctional radiation-resistant shielding polyester filament according to claim 1, characterized in that: The lignin dispersion in step (1) is composed of nano-lignin, N,N-dimethylformamide, and KH-550, and the mass ratio thereof is 1:15:0.

02.

3. The preparation method of a flexible multifunctional radiation-resistant shielding polyester filament according to claim 2, characterized in that: The particle size of the nano-lignin is 10-50 nm.

4. The preparation method of a flexible multifunctional radiation-resistant shielding polyester filament according to claim 1, characterized in that: The spinning in step (1) is electrostatic spinning, and its process parameters are: voltage of 15-20 kV, receiving distance of 8-17 cm, and spinning rate of 0.1-0.5 m / s.

5. The preparation method of a flexible multifunctional radiation-resistant shielding polyester filament according to claim 1, characterized in that: The hot pressing in step (1) is performed at a temperature of 120-160° C., a pressure of 0.9-2 MPa, and a time of 1-4 h.

6. The preparation method of a flexible multifunctional radiation-resistant shielding polyester filament according to claim 1, characterized in that: The specific method of calcination in step (1) is as follows: first, treat at 250°C for 2 hours to remove the solvent and low molecular weight organic matter, then introduce nitrogen at 0.06L / min, increase the temperature to 600°C at 5°C / min, and keep warm for 1 hour, then introduce argon and ammonia, increase the temperature to 850°C at 10°C / min, and keep warm for 2-4 hours.

7. The preparation method of a flexible multifunctional radiation-resistant shielding polyester filament according to claim 6, characterized in that: The volume ratio of the argon gas to the ammonia gas is 1:

1.

8. The preparation method of a flexible multifunctional radiation-resistant shielding polyester filament according to claim 1, characterized in that: The silane coupling agent in step (2) is at least one of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, glycidoxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethoxysilane and N-β(aminoethyl)-γ-aminopropylmethyldimethoxysilane.

9. The preparation method of a flexible multifunctional radiation-resistant shielding polyester filament according to claim 1, characterized in that: The compatibilizer is prepared by mixing maleic anhydride grafted EVA and maleic anhydride grafted HDPE in a mass ratio of 1-2:0.5-1.2.