Preparation method of double-layer shading fabric

Abstract

The invention discloses a preparation method of a double-layer shading fabric, and relates to the technical field of textiles. According to the invention, dibenzyl phosphite reacts with ethambutol, benzyl is introduced, a P-N bond is formed, thermal stability and oxidation resistance are improved, phosphite is introduced, surface resistance of the material is reduced, a decomposition reaction is carried out during combustion to generate a non-combustible product, a nitrogen element is assisted, a porous foamy carbon layer is generated, oxygen is isolated from entering, and antistatic and flame-retardant effects are realized; the modified flame retardant prepared by matching tetraphenyl silicate and tetrachlorobisphenol A contains more chlorine elements, interrupts a combustion chain reaction, forms a flame-retardant carbonized layer, assists phenyl silicate, improves the thermal stability and improves the ignition point, so that the flame-retardant performance of the polyester is improved, and the flame-retardant performance of the polyester is improved. A glassy covering layer can be formed on the surface of the material during combustion, and is matched with a carbonization layer to jointly isolate oxygen and combustible materials, so that flame spreading is quickly inhibited, and the flame-retardant effect is further enhanced.

Description

Technical Field

[0001] This invention relates to the field of textile technology, specifically to a method for preparing a double-layer blackout fabric. Background Technology

[0002] Blackout fabrics, when exposed to sunlight for extended periods, absorb ultraviolet rays and can easily cause fires.

[0003] Light-blocking fabrics made of chemical materials are highly prone to static electricity, which not only affects comfort but may also interfere with some precision electronic devices. Adding inorganic conductive fillers, such as graphite and carbon black, can significantly improve the conductivity and antistatic properties of the material. However, these inorganic conductive fillers have poor interfacial bonding with the polymer matrix, are unevenly dispersed, and their large addition amounts often lead to a decline in mechanical and processing properties. Existing organic antistatic agents such as ammonium salts, quaternary ammonium salts, and alkyl amino acid salts have poor durability, are easily lost during friction and washing, and fail quickly. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing a double-layer light-blocking fabric to solve the problems existing in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for preparing a double-layer light-blocking fabric, comprising the following preparation steps:

[0006] (1) Mix 18-90 parts of tetraphenyl silicate, 10-50 parts of tetrachlorobisphenol A and 0.2-1.2 parts of sodium acetate evenly, heat to 150-170℃, stir at 100 rpm for 1-2 hours under a certain reaction pressure, heat to 230-240℃ and react for 4-8 hours, reduce the pressure to 0.2-0.3 kPa, cool to 30℃, filter to obtain solid, wash twice with methanol, and dry at 40-50℃ for 4-8 hours to obtain modified flame retardant;

[0007] (2) Mix 5-15 parts of dibenzyl phosphite, 7-21 parts of carbon tetrachloride, and 3-9 parts of tetrahydrofuran evenly, add 4-12 parts of triethylamine and 4.5-13.5 parts of ethambutol, stir at 20-30℃ and 80rpm for 10-14h, filter the filtrate, concentrate it, and dry it at 60-70℃ for 3-5h to obtain the modifier;

[0008] (3) Mix 6-10 parts of modifier, 34-58 parts of ethylene glycol, and 26-42 parts of terephthalic acid evenly, add 1-3 parts of catalyst, react at 200-220℃ for 3-5 hours, filter to obtain solid, wash twice with ethanol, and dry at 50-60℃ for 2-4 hours to obtain modified polyester.

[0009] (4) Mix 77-93 parts of modified polyester and 8-12 parts of modified flame retardant evenly, place them in an internal mixer and mix for 20-40 minutes, then extrude and granulate them through an extruder to obtain composite modified polyester.

[0010] (5) The composite modified polyester is placed in a spinning machine to spin, and warp and weft yarns are interwoven to form a double-layer structure, resulting in a double-layer blackout fabric.

[0011] Furthermore, the reaction pressure in step (1) is 4 to 6 kPa.

[0012] Further, the concentration in step (2) is carried out at a vacuum of -0.09 MPa and a temperature of 60-70°C for 2-4 hours.

[0013] Furthermore, the catalyst in step (3) is any one of tetrabutyl titanate, antimony acetate, and germanium dioxide.

[0014] Furthermore, the mixing temperature in step (4) is 170–190°C.

[0015] Furthermore, the extruder parameters in step (4) are: head temperature 165–185°C, screw speed 170–230 r / min, extrusion pressure 8–12 MPa, and shear rate 180–240 s. -1 .

[0016] Furthermore, the spinning machine parameters in step (5) are: spinning temperature 280-300℃, winding roller temperature 60-100℃, speed 400-500m / min, drawing temperature 80-120℃, and speed 100-200m / min.

[0017] Furthermore, in step (5), the warp yarn specification is 300D / 24F; the weft yarn specification is 420D / 48F.

[0018] Furthermore, in step (5), the total number of warp filaments in the warp yarn is 20,000 to 50,000, and the warp filament density is 120 to 140 teeth; the total number of weft filaments in the weft yarn is 10,000 to 20,000, and the weft filament density is 60 to 120 teeth.

[0019] Furthermore, the double-layer structure described in step (5) consists of two sets of warp yarns and three sets of weft yarns, with a weft yarn arrangement ratio of 1:1:1.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0021] This invention uses modified polyester and modified flame retardant mixed and spun into warp and weft yarns, which are then interwoven to form a double-layer light-blocking fabric, achieving high strength, antistatic properties, and flame retardancy.

[0022] First, by reacting dibenzyl phosphite with ethylaminobutanol, benzyl groups are introduced and stable PN bonds are formed, significantly improving thermal stability and antioxidant properties. Simultaneously, the introduction of phosphite into the molecular chain reduces the surface resistance of the material, thus achieving an antistatic effect. Furthermore, it allows the polyester to decompose during combustion, generating non-combustible products such as phosphates and phosphate esters. With the assistance of nitrogen elements, a porous foam carbon layer is formed, preventing oxygen from entering and achieving a flame-retardant effect. Then, it participates in the polymerization reaction of polyethylene terephthalate to obtain a modified polyester, forming a stable three-dimensional network structure, significantly improving the polyester's thermal stability and mechanical properties. Combined with modified flame retardants, it rapidly inhibits the spread of flame, further enhancing the flame-retardant effect.

[0023] Secondly, the modified flame retardant is prepared by the condensation reaction of tetraphenyl silicate and tetrachlorobisphenol A, which makes it contain more chlorine. This allows it to capture free radicals in the combustion reaction, interrupting the chain reaction of combustion. At the same time, the residue after the hydrogen chloride is decomposed during combustion can promote the dehydration and carbonization of the polymer material, forming a flame-retardant carbonized layer. This reduces the amount of low molecular weight pyrolysis products generated and prevents the pyrolysis products from continuing to burn, thus initially achieving flame retardant properties. It also assists phenyl silicate in improving thermal stability and increasing the ignition point. During combustion, it can form a glassy coating layer on the surface of the material, which, together with the carbonized layer, isolates oxygen and combustibles, thereby inhibiting the combustion of the flame and achieving a flame-retardant effect. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0025] To more clearly illustrate the method provided by the present invention, the following embodiments are provided in detail. The test methods for various indicators of the double-layer blackout fabric produced in the following embodiments are as follows:

[0026] Tear strength: Examples and comparative examples of the same size were tested in accordance with GB / T 3917.1.

[0027] Limiting oxygen index: Examples and comparative examples of the same size were tested in accordance with ISO 4589-2.

[0028] Vertical burning test: Take the same size examples and comparative examples, and test according to UL-94.

[0029] Surface resistance: Examples and comparative examples of the same size were tested using a surface resistance tester in accordance with AATCC 76-2019.

[0030] Example 1: (1) Mix 18 parts of tetraphenyl silicate, 10 parts of tetrachlorobisphenol A and 0.2 parts of sodium acetate evenly, heat to 150°C, stir at 100 rpm for 1 h under a reaction pressure of 4 kPa, heat to 230°C, react for 4 h, reduce the pressure to 0.2 kPa, cool to 30°C, filter to obtain solid, wash twice with methanol, dry at 40°C for 4 h to obtain modified flame retardant;

[0031] (2) Mix 5 parts of dibenzyl phosphite, 7 parts of carbon tetrachloride, and 3 parts of tetrahydrofuran evenly, add 4 parts of triethylamine and 4.5 parts of ethambutol, stir at 20°C and 80 rpm for 10-14 h, filter the filtrate, concentrate at -0.09 MPa and 60°C for 2 h, and dry at 60°C for 3 h to obtain the modifier.

[0032] (3) Mix 6 parts of modifier, 34 parts of ethylene glycol and 26 parts of terephthalic acid evenly, add 1 part of tetrabutyl titanate, react at 200℃ for 3h, filter to obtain solid, wash twice with ethanol, dry at 50℃ for 2h to obtain modified polyester.

[0033] (4) Mix 77 parts of modified polyester and 8 parts of modified flame retardant evenly, place them in an internal mixer and mix at 170°C for 20 min, then extrude and granulate through an extruder to obtain composite modified polyester; the parameters of the extruder are: feed head temperature 165°C, screw speed 170 r / min, extrusion pressure 8 MPa, and shear rate 180 s. -1 .

[0034] (5) The composite modified polyester is placed in a spinning machine for spinning to produce warp yarns with a specification of 300D / 24F, a total of 20,000 yarns, and a density of 120 teeth, and weft yarns with a specification of 420D / 48F, a total of 10,000 yarns, and a density of 60 teeth. The two sets of warp yarns and three sets of weft yarns are interwoven to form a double-layer structure, resulting in a double-layer light-blocking fabric. The parameters of the spinning machine are: spinning temperature 280℃, winding roller temperature 60℃, speed 400m / min, stretching temperature 80℃, and speed 100m / min. The weft yarn arrangement ratio is 1:1:1.

[0035] Example 2: (1) Mix 54 parts of tetraphenyl silicate, 30 parts of tetrachlorobisphenol A and 0.7 parts of sodium acetate evenly, heat to 160°C, stir at 100 rpm for 1.5 h under a reaction pressure of 5 kPa, heat to 235°C, react for 6 h, reduce the pressure to 0.25 kPa, cool to 30°C, filter to obtain solid, wash twice with methanol, dry at 45°C for 6 h to obtain modified flame retardant;

[0036] (2) Mix 10 parts of dibenzyl phosphite, 14 parts of carbon tetrachloride and 6 parts of tetrahydrofuran evenly, add 8 parts of triethylamine and 9 parts of ethambutol, stir at 25°C and 80 rpm for 12 h, filter the filtrate, concentrate at -0.09 MPa and 65°C for 3 h, and dry at 65°C for 4 h to obtain the modifier.

[0037] (3) Mix 8 parts of modifier, 46 parts of ethylene glycol and 34 parts of terephthalic acid evenly, add 2 parts of antimony acetate, react at 210℃ for 4h, filter to obtain solid, wash twice with ethanol, dry at 55℃ for 3h to obtain modified polyester.

[0038] (4) Mix 85 parts of modified polyester and 10 parts of modified flame retardant evenly, place them in an internal mixer and mix at 180°C for 30 min, then extrude and granulate through an extruder to obtain composite modified polyester; the parameters of the extruder are: feed head temperature 175°C, screw speed 200 r / min, extrusion pressure 10 MPa, and shear rate 210 s. -1 .

[0039] (5) The composite modified polyester is placed in a spinning machine for spinning to produce warp yarns with a specification of 300D / 24F, a total of 35,000 yarns, and a density of 130 teeth, and weft yarns with a specification of 420D / 48F, a total of 15,000 yarns, and a density of 90 teeth. The two sets of warp yarns and three sets of weft yarns are interwoven to form a double-layer structure, resulting in a double-layer light-blocking fabric. The parameters of the spinning machine are: spinning temperature 290℃, winding roller temperature 80℃, speed 450m / min, stretching temperature 100℃, and speed 150m / min. The weft yarn arrangement ratio is 1:1:1.

[0040] Example 3: (1) Mix 90 parts of tetraphenyl silicate, 50 parts of tetrachlorobisphenol A and 1.2 parts of sodium acetate evenly, heat to 170°C, stir at 100 rpm for 2 hours under a reaction pressure of 6 kPa, heat to 240°C, react for 8 hours, reduce the pressure to 0.3 kPa, cool to 30°C, filter to obtain solid, wash twice with methanol, dry at 50°C for 8 hours to obtain modified flame retardant;

[0041] (2) Mix 15 parts of dibenzyl phosphite, 21 parts of carbon tetrachloride and 9 parts of tetrahydrofuran evenly, add 12 parts of triethylamine and 13.5 parts of ethambutol, stir at 30℃ and 80rpm for 14h, filter the filtrate, concentrate at -0.09MPa and 70℃ for 4h, and dry at 70℃ for 5h to obtain the modifier;

[0042] (3) Mix 10 parts of modifier, 58 parts of ethylene glycol and 42 parts of terephthalic acid evenly, add 3 parts of germanium dioxide, react at 220℃ for 5h, filter to obtain solid, wash twice with ethanol, dry at 60℃ for 4h to obtain modified polyester.

[0043] (4) Mix 93 parts of modified polyester and 12 parts of modified flame retardant evenly, place them in an internal mixer and mix at 190°C for 40 min, then extrude and granulate through an extruder to obtain composite modified polyester; the parameters of the extruder are: feed head temperature 185°C, screw speed 230 r / min, extrusion pressure 12 MPa, and shear rate 240 s. -1 .

[0044] (5) The composite modified polyester is placed in a spinning machine for spinning to produce warp yarns with a specification of 300D / 24F, a total of 50,000 yarns, and a density of 140 teeth, and weft yarns with a specification of 420D / 48F, a total of 20,000 yarns, and a density of 120 teeth. The two sets of warp yarns and three sets of weft yarns are interwoven to form a double-layer structure, resulting in a double-layer light-blocking fabric. The parameters of the spinning machine are: spinning temperature 300℃, winding roller temperature 100℃, speed 500m / min, stretching temperature 120℃, and speed 200m / min. The weft yarn arrangement ratio is 1:1:1.

[0045] Comparative Example 1: The difference between Comparative Example 1 and Example 2 is that step (2) is omitted, and step (3) is changed to: 8 parts of ethylamine butanol, 46 parts of ethylene glycol, and 34 parts of terephthalic acid are mixed evenly, 2 parts of antimony acetate are added, and the mixture is reacted at 210°C for 4 hours. The solid is filtered, washed twice with ethanol, and dried at 55°C for 3 hours to obtain the modified polyester. The remaining steps are the same as in Example 2.

[0046] Comparative Example 2: The difference between Comparative Example 2 and Example 2 is that step (2) is omitted, and step (3) is changed to: 8 parts of dibenzyl phosphite, 46 parts of ethylene glycol, and 34 parts of terephthalic acid are mixed evenly, 2 parts of antimony acetate are added, and the mixture is reacted at 210°C for 4 hours. The solid is filtered, washed twice with ethanol, and dried at 55°C for 3 hours to obtain the modified polyester. The remaining steps are the same as in Example 2.

[0047] Comparative Example 3: The difference between Comparative Example 3 and Example 2 lies in step (3). Step (3) is changed to: mixing 46 parts of ethylene glycol and 34 parts of terephthalic acid evenly, adding 2 parts of antimony acetate, reacting at 210°C for 4 hours, filtering to obtain the solid, washing twice with ethanol, and drying at 55°C for 3 hours to obtain polyester; Step (4) is changed to: mixing 85 parts of polyester, 8 parts of modifier, and 10 parts of modified flame retardant evenly, placing them in a mixer and mixing at 180°C for 30 minutes, then extruding and granulating through an extruder to obtain composite modified polyester. The remaining steps are the same as in Example 2.

[0048] Comparative Example 4: The difference between Comparative Example 4 and Example 2 is that step (1) is omitted, and step (4) is changed to: 85 parts of modified polyester and 10 parts of tetrachlorobisphenol A are mixed evenly, placed in a mixer and mixed at 180°C for 30 minutes, and then extruded and granulated to obtain composite modified polyester. The remaining steps are the same as in Example 2.

[0049] Comparative Example 5: The difference between Comparative Example 5 and Example 2 is that step (1) is omitted, and step (4) is changed to: 85 parts of modified polyester and 10 parts of tetraphenyl silicate are mixed evenly, placed in a mixer and mixed at 180°C for 30 minutes, and then extruded and granulated to obtain composite modified polyester. The remaining steps are the same as in Example 2.

[0050] Example of effect

[0051] Table 1 below presents the performance analysis results of the double-layer blackout fabrics used in Examples 1 to 3 and Comparative Examples 1 to 5 of the present invention.

[0052] Table 1

[0053] Tear strength / N Limiting oxygen index / % Vertical burning test Surface resistance / Ω Example 1 85 36.1 V-0 <![CDATA[6.2x10 7 ]]> Example 2 88 35.8 V-0 <![CDATA[6.5x10 7 ]]> Example 3 82 36.3 V-0 <![CDATA[6.9x10 7 ]]> Comparative Example 1 71 25.4 V-2 <![CDATA[3.0x10 14 ]]> Comparative Example 2 43 30.6 V-1 <![CDATA[7.3x10 10 ]]> Comparative Example 3 50 29.5 V-1 <![CDATA[8.7x10 9 ]]> Comparative Example 4 66 18.0 Not passed <![CDATA[4.1x10 10 ]]> Comparative Example 5 74 17.2 Not passed <![CDATA[5.4x10 9 ]]>

[0054] A comparison of the experimental data from Examples 1, 2, and 3 with Comparative Example 1 reveals that introducing benzyl groups into dibenzyl phosphite and reacting it chemically with ethambutol significantly improves thermal stability and antioxidant properties. Simultaneously, introducing phosphite into the molecular chain reduces the surface resistance of the material, thus achieving an antistatic effect. Furthermore, it allows the polyester to decompose during combustion, generating non-combustible products such as phosphates and phosphate esters, thereby achieving a flame-retardant effect. A comparison of the experimental data from Examples 1, 2, and 3 with Comparative Example 2 reveals that ethambutol can participate in the polymerization reaction of polyester, forming a three-dimensional network structure, which significantly improves stability and mechanical strength. Simultaneously, the nitrogen element can assist the phosphate ester in forming a porous foam carbon layer, isolating oxygen and achieving a flame-retardant effect. A comparison of the experimental data from Examples 1, 2, and 3 with Comparative Example 3 reveals that the modifier… Containing multiple hydroxyl groups, it can participate in the polymerization reaction of polyethylene terephthalate, forming a stable three-dimensional network structure, significantly improving the thermal stability and mechanical properties of polyester. A comparison of experimental data from Examples 1, 2, and 3 with Comparative Example 4 reveals that tetraphenyl silicate can improve thermal stability, increase the material's ignition point, and form a glassy coating on the material surface during combustion, isolating oxygen and thus inhibiting flame combustion, achieving a flame-retardant effect. A comparison of experimental data from Examples 1, 2, and 3 with Comparative Example 5 reveals that tetrachlorobisphenol A contains a relatively high amount of chlorine, which can capture free radicals in the combustion reaction, interrupting the chain reaction of combustion. Simultaneously, the residue after the decomposition of hydrogen chloride during combustion can promote the dehydration and carbonization of the polymer material, forming a flame-retardant carbonized layer, reducing the generation of low-molecular-weight pyrolysis products, and preventing the pyrolysis products from continuing to burn.

[0055] 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 implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a double-layer light-blocking fabric, characterized in that, The preparation steps include the following: (1) Mix 18-90 parts of tetraphenyl silicate, 10-50 parts of tetrachlorobisphenol A and 0.2-1.2 parts of sodium acetate evenly, heat to 150-170℃, stir at 100 rpm for 1-2 hours under a certain reaction pressure, heat to 230-240℃ and react for 4-8 hours, reduce the pressure to 0.2-0.3 kPa, cool to 30℃, filter to obtain solid, wash twice with methanol, and dry at 40-50℃ for 4-8 hours to obtain modified flame retardant; (2) Mix 5-15 parts of dibenzyl phosphite, 7-21 parts of carbon tetrachloride, and 3-9 parts of tetrahydrofuran evenly, add 4-12 parts of triethylamine and 4.5-13.5 parts of ethambutol, stir at 20-30℃ and 80rpm for 10-14h, filter the filtrate, concentrate it, and dry it at 60-70℃ for 3-5h to obtain the modifier; (3) Mix 6-10 parts of modifier, 34-58 parts of ethylene glycol, and 26-42 parts of terephthalic acid evenly, add 1-3 parts of catalyst, react at 200-220℃ for 3-5 hours, filter to obtain solid, wash twice with ethanol, and dry at 50-60℃ for 2-4 hours to obtain modified polyester. (4) Mix 77-93 parts of modified polyester and 8-12 parts of modified flame retardant evenly, place them in an internal mixer and mix for 20-40 minutes, then extrude and granulate them through an extruder to obtain composite modified polyester. (5) The composite modified polyester is placed in a spinning machine to spin, and warp and weft yarns are interwoven to form a double-layer structure, resulting in a double-layer blackout fabric.

2. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, The reaction pressure in step (1) is 4 to 6 kPa.

3. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, The concentration in step (2) is carried out at a vacuum of -0.09 MPa and a temperature of 60-70°C for 2-4 hours.

4. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, The catalyst mentioned in step (3) is any one of tetrabutyl titanate, antimony acetate, and germanium dioxide.

5. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, The mixing temperature in step (4) is 170-190℃.

6. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, The extruder parameters in step (4) are: head temperature 165-185℃, screw speed 170-230 r / min, extrusion pressure 8-12 MPa, and shear rate 180-240 s. -1 .

7. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, The parameters of the spinning machine in step (5) are: spinning temperature 280-300℃, winding roller temperature 60-100℃, speed 400-500m / min, drawing temperature 80-120℃, and speed 100-200m / min.

8. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, The warp yarn specification in step (5) is 300D / 24F; the weft yarn specification is 420D / 48F.

9. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, In step (5), the total number of warp yarns in the warp yarn is 20,000 to 50,000, and the warp yarn density is 120 to 140 teeth; the total number of weft yarns in the weft yarn is 10,000 to 20,000, and the weft yarn density is 60 to 120 teeth.

10. The method for preparing a double-layer light-blocking fabric according to claim 1, characterized in that, The double-layer structure described in step (5) consists of two sets of warp yarns and three sets of weft yarns, with a weft yarn arrangement ratio of 1:1:1.