Flame-retardant polyester fabric and preparation method thereof

Abstract

The present application belongs to the polyester fiber field, and particularly relates to a kind of flame-retardant polyester fabric, and its preparation method includes: 100 parts of modified polyester masterbatch, 5~15 parts of mica powder, 1~5 parts of antioxidant, 1~3 parts of ultraviolet resistance agent, 8~10 parts of polyethylene glycol 20000 are mixed uniformly, then melt spinning is carried out on spinning machine to obtain polyester fiber, finally, the polyester fiber is woven into flame-retardant polyester fabric by textile machine.The polyester fabric prepared by the present application has excellent flame-retardant property, the initial limiting oxygen index reaches 39.5%, the vertical combustion property UL-94 reaches V0 level, and after 100 times of washing, the polyester fabric still has high limiting oxygen index, and has good washing resistance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of polyester fibers, and particularly relates to a flame-retardant polyester fabric and a preparation method thereof. BACKGROUND

[0002] Polyester fabric, commonly known as polyester fiber or PET, is a synthetic fiber fabric obtained by esterification or exchange of terephthalic acid and ethylene glycol, followed by a series of processing processes such as melt spinning and weaving. Polyester is the synthetic fiber with the largest output and the widest application range in the world, and has many excellent practical properties such as strong resistance, good resilience, good wrinkle resistance, good heat resistance, and durability, and is widely used in clothing manufacturing, decorative products, automotive interiors, industrial textiles, and other special purpose textiles. Polyester fiber was first developed in a laboratory in the United Kingdom in 1941, and began large-scale industrial production in the United States in 1953, since then it has been rapidly applied and developed worldwide. Since 1972, the world production of polyester fiber has exceeded that of polyamide fiber, and has since become the world's largest synthetic fiber.

[0003] The molecular chain of PET only has benzene ring, ester bond and short-chain alkane, and does not have any flame-retardant elements, therefore, the limiting index of polyester fabric is generally about 9-22, which belongs to flammable materials, and is easily ignited when encountering flame, and releases a large amount of heat and flame-dripping during the combustion process, causing rapid spread of fire and secondary burns to people or animals, posing a great threat to people's life and property safety. In order to improve the fire safety of polyester fabric during use, it needs to be flame-retardant modified. As a synthetic fiber, there are many ways to improve the polyester fabric. From the synthesis stage of PET molecules, flame retardants are introduced into the PET molecular chain by means of copolymerization, etc., to change the molecular structure to obtain flame-retardant PET polymer; the flame retardant can also be directly blended with ordinary PET raw materials during the melt spinning of the fiber, and the flame-retardant PET fiber is obtained by spinning; and the flame-retardant liquid dip-padding, flame-retardant coating, and flame-retardant impregnation are used for flame-retardant treatment of the polyester fabric, and the flame retardant exists on the surface of the PET fiber by physical adsorption, deposition, physical entanglement, and intermolecular hydrogen bonding.

[0004] In summary, the excellent use performance of polyester fabric brings great convenience to people's production and life, but its flammability also threatens people's property and personal safety, and it is very urgent and necessary to improve the flame-retardant performance of polyester fabric. SUMMARY

[0005] Therefore, the purpose of the present application is to provide a polyester fabric with excellent flame-retardant performance and good washing resistance, and a preparation method thereof. The present application is realized by the following technical scheme:

[0006] A preparation method of a flame-retardant polyester fabric, comprising the following steps:

[0007] Step 1: preparation of modified polyester masterbatch

[0008] terephthalic acid, ethylene glycol and catalyst Sb2O3 into the reaction kettle and mix uniformly, esterification, pre-polycondensation to obtain a prepolymer; then add flame-retardant modification monomer A to the prepolymer, and prepare a modified polyester through polycondensation reaction and final polycondensation reaction; the modified polyester is extruded, granulated and dried to obtain a modified polyester masterbatch;

[0009] The structure of the flame-retardant modification monomer A is: ;

[0010] Step 2: preparation of modified polyester masterbatch

[0011] In weight parts, 100 parts of the modified polyester masterbatch, 5-15 parts of mica powder, 1-5 parts of an antioxidant, 1-3 parts of an ultraviolet-resistant agent, and 8-10 parts of polyethylene glycol 20000 are mixed uniformly, and then melt spinning is performed on a spinning machine to obtain a polyester fiber, and finally the polyester fiber is spun into a flame-retardant polyester fabric through a textile machine.

[0012] In some embodiments, the antioxidant is selected from one or more of triphenyl phosphite, triphenyl phosphate, antioxidant HP-136, antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 1068.

[0013] In some embodiments, the ultraviolet-resistant agent is selected from one or more of zirconium oxide, silicon dioxide, calcium oxide, antimony pentoxide, cerium dioxide, yttrium oxide, zinc oxide, nickel oxide, chromium oxide, and titanium dioxide.

[0014] In some embodiments, the molar ratio of terephthalic acid to ethylene glycol is 1:(1-1.5); the molar ratio of terephthalic acid to flame-retardant modification monomer A is 1:(0.05-0.2); and the molar ratio of terephthalic acid to catalyst Sb2O3 is 1:(0.01-0.1).

[0015] In some embodiments, the esterification temperature is 230-250°C, the esterification pressure is 0.1-0.5 MPa, and the esterification time is 1-3 h.

[0016] In some embodiments, the pre-polycondensation temperature is 250-270°C, the pre-polycondensation pressure is -0.02--0.01 MPa, and the pre-polycondensation time is 30-60 min.

[0017] In some embodiments, the polycondensation temperature is 270-290 DEG C, the polycondensation vacuum degree is 1-5 kPa, and the polycondensation time is 30-60 min.

[0018] In some embodiments, the final polycondensation temperature is 280-300 DEG C, the final polycondensation vacuum degree is 100-200 Pa, and the final polycondensation time is 60-90 min.

[0019] In some embodiments, the rotating speed of the extruder is 20-50 r / min, the temperature of the first zone of the extruder is 265 DEG C, the temperature of the second zone is 290 DEG C, the temperature of the third zone is 280 DEG C, and the temperature of the fourth zone is 270 DEG C.

[0020] In some embodiments, in step 2, the spinning temperature of the spinning machine is 250-280 DEG C, the rotating speed of the screw is 500-800 r / min, and the winding speed is 1000-1200 r / min.

[0021] The application also protects the flame-retardant polyester fabric prepared by the above method.

[0022] The application has the following beneficial effects:

[0023] 1) The polyester fabric prepared by the application has excellent flame-retardant performance, the initial limiting oxygen index reaches 39.5%, the vertical combustion performance UL-94 reaches V0 level, and after 100 times of washing, the polyester fabric still has a high limiting oxygen index and has good washing resistance.

[0024] 2) The flame-retardant modified monomer A has two carboxyl groups, can participate in the polycondensation reaction as a polymerization monomer, and embeds the flame-retardant structure into the polymer, so that it has excellent washing resistance; on the other hand, the flame-retardant modified monomer A contains triazine and borate structures, which have good flame-retardant performance, and can realize synergistic and efficient flame-retardant when introduced into the polyester fabric. DETAILED DESCRIPTION

[0026] The technical solutions of the application will be described below in conjunction with the embodiments, obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0027] The endpoints of the ranges of the present invention and any values stated herein are not limited to the precise values stated. The ranges and values are understood to be approximate, and to include values near the recited ranges and values. For ranges of numerical values, the endpoints of the ranges are included, between the endpoints of the ranges, between the endpoints of the ranges and the individual points, and between the individual points, to form new ranges of values that are contemplated by the present invention.

[0028] Unless otherwise specified, all raw materials and reagents of the present invention are conventional market raw materials and reagents.

[0029] Preparation Example 1 Synthesis of flame-retardant modified monomer A

[0030] Step 1: Synthesis of intermediate compound III (referring to the method disclosed in CN116640126A)

[0031]

[0032] Under nitrogen protection, compound I (0.1 mol), compound II (0.2 mol), KOAc (0.3 mol), Pd(dppf)Cl2(0.005 mol) and THF (500 mL) were added to the reactor, and the mixture solution of the above reactants was heated to reflux for 7 hours. After the reaction was completed, it was cooled to room temperature, distilled water was added, and the filter cake was obtained by suction filtration and dried in a vacuum oven, and purified by silica gel column separation (n-hexane: ethyl acetate = 1:1) to obtain intermediate compound III with a yield of 83.5% and an HPLC purity of 99.8%.

[0033] LC-MS (ESI): [M+H] + = 368.2.

[0034] Step 2: Synthesis of flame-retardant modified monomer A

[0035]

[0036] Step S1: Sodium pieces (0.1 mol) were added to the reactor, and anhydrous ethanol (200 mL) was immediately added, and stirred at room temperature until the sodium pieces completely disappeared. Diethyl malonate (0.1 mol) was added, and the reaction was stirred at room temperature for 1 h, then compound III (0.12 mol) was added, and the reaction was stirred at 80°C for 2 h, and the reaction progress was tracked by TLC spot plate (petroleum ether: ethyl acetate = 8:1). After the reaction was completed, the solid impurities were removed by suction filtration, and the reaction liquid was rotary evaporated to obtain intermediate compound V, which was directly used in the next step reaction.

[0037] Step S2: The compound V obtained in step S1 was added into a reactor, then a mixed solvent of dichloromethane:methanol (V:V = 9:1) (200 mL), sodium hydroxide (0.4 mol) was added, stirred at room temperature for 6 h, and the reaction progress was tracked by TLC spot plate (petroleum ether:ethyl acetate = 8:1). After the reaction was completed, the reaction solution was rotary evaporated to obtain the intermediate compound VI;

[0038] Step S3: Water (100 mL) was added to the intermediate compound VI obtained in step S2, and 1M hydrochloric acid was slowly added dropwise to adjust the pH to 2. Then water (100 mL) was added, extracted with ethyl acetate (200 mL x 3), the organic phase was combined, washed with saturated sodium chloride solution (100 mL x 3), dried over anhydrous sodium sulfate, then filtered, rotary evaporated to obtain a crude product, which was separated and purified by silica gel column chromatography to obtain the compound A, with a total yield of 60.8% and a HPLC purity of 99.6%.

[0039] 1 H-NMR (400 MHz, DMSO- d 6):δ(ppm): 11.5(s,2H), 4.68-4.61(m,1H), 1.25(s,24H)。

[0040] Example 1

[0041] A preparation method of a flame-retardant polyester fabric, the specific steps of which are as follows:

[0042] Step 1: Preparation of modified polyester masterbatch

[0043] Terephthalic acid, ethylene glycol and catalyst Sb2O3 were added into a reaction kettle and mixed uniformly, the system was checked for air tightness, nitrogen was filled to exclude air in the reaction kettle, and a prepolymer was obtained through esterification and pre-polycondensation; then the flame-retardant modified monomer A (obtained in Preparation Example 1) was added into the prepolymer, and the desired modified polyester was prepared through polycondensation reaction and final polycondensation reaction, and finally the modified polyester masterbatch was obtained through extrusion granulation and drying.

[0044] The molar ratio of terephthalic acid to ethylene glycol is 1:1.15;

[0045] The molar ratio of terephthalic acid to flame-retardant modified monomer A is 1:0.15;

[0046] The molar ratio of terephthalic acid to catalyst Sb2O3 is 1:0.02;

[0047] The esterification temperature is 230°C, the esterification pressure is 0.2 MPa, and the esterification time is 2.0 h;

[0048] The pre-polycondensation temperature is 250°C, the pre-polycondensation pressure is -0.01 MPa, and the pre-polycondensation time is 45 min;

[0049] The polycondensation temperature is 270℃, the polycondensation vacuum degree is 1kPa, and the polycondensation time is 60min;

[0050] The final polycondensation temperature is 280℃, the final polycondensation vacuum degree is 200Pa, and the final polycondensation time is 90min.

[0051] The rotating speed of the extruder is 50r / min, the temperature of the first zone of the extruder is 265℃, the temperature of the second zone is 290℃, the temperature of the third zone is 280℃, and the temperature of the fourth zone is 270℃.

[0052] Step 2: Preparation method of flame-retardant polyester fabric

[0053] According to parts by weight, 100 parts of modified polyester masterbatch (obtained in step 1), 10 parts of mica powder (produced by Lingshou County Tuolin Mineral Product Processing Factory, particle size is 10μm, sand content is <3%), 2 parts of antioxidant 1010, 3 parts of ultraviolet resistant agent zinc oxide, and 10 parts of polyethylene glycol 20000 are uniformly mixed, and then melt spinning is carried out on a spinning machine, the spinning temperature in the spinning machine is 265℃, the screw rotating speed is 600r / min, and the winding speed is 1200r / min, to obtain polyester fiber, and finally the polyester fiber is spun into flame-retardant polyester fabric through a textile machine.

[0054] Example 2

[0055] A preparation method of flame-retardant polyester fabric, the specific steps are as follows:

[0056] Step 1: Preparation of modified polyester masterbatch

[0057] Terephthalic acid, ethylene glycol and catalyst Sb2O3 are added into a reaction kettle and uniformly mixed, the system air tightness is checked, nitrogen is filled to exclude air in the reaction kettle, and a prepolymer is obtained through esterification and pre-polycondensation; then the flame-retardant modification monomer A (obtained in preparation example 1) is added into the prepolymer, and the desired modified polyester is prepared through polycondensation reaction and final polycondensation reaction, and finally the modified polyester masterbatch is obtained through extrusion granulation and drying.

[0058] The molar ratio of terephthalic acid to ethylene glycol is 1:1.2;

[0059] The molar ratio of terephthalic acid to flame-retardant modification monomer A is 1:0.1;

[0060] The molar ratio of terephthalic acid to catalyst Sb2O3 is 1:0.01;

[0061] The esterification temperature is 240℃, the esterification pressure is 0.2MPa, and the esterification time is 1.5h;

[0062] The pre-polycondensation temperature is 260℃, the pre-polycondensation pressure is -0.02MPa, and the pre-polycondensation time is 30min.

[0063] The polycondensation temperature is 280℃, the polycondensation vacuum degree is 1kPa, and the polycondensation time is 40min.

[0064] The final polycondensation temperature is 290℃, the final polycondensation vacuum degree is 200Pa, and the final polycondensation time is 60min.

[0065] The rotating speed of the extruder is 50r / min, the temperature of the first zone of the extruder is 265℃, the temperature of the second zone is 290℃, the temperature of the third zone is 280℃, and the temperature of the fourth zone is 270℃.

[0066] Step 2: Preparation method of flame-retardant polyester fabric

[0067] In parts by weight, 100 parts of modified polyester masterbatch (obtained in step 1), 8 parts of mica powder (produced by Lingshou County Tuolin Mineral Product Processing Factory, particle size is 10μm, sand content is <3%), 3 parts of antioxidant 168, 2 parts of ultraviolet resistant agent titanium dioxide, and 10 parts of polyethylene glycol 20000 are uniformly mixed, and then melt spinning is carried out on a spinning machine, the spinning temperature in the spinning machine is 265℃, the screw rotating speed is 600r / min, and the winding speed is 1200r / min, to obtain polyester fiber, and finally the polyester fiber is spun into flame-retardant polyester fabric through a textile machine.

[0068] Example 3

[0069] A preparation method of flame-retardant polyester fabric, the specific steps are as follows:

[0070] Step 1: Preparation of modified polyester masterbatch

[0071] Terephthalic acid, ethylene glycol and catalyst Sb2O3 are added into a reaction kettle and uniformly mixed, the system air tightness is checked, nitrogen is filled to exclude air in the reaction kettle, and a pre-polymer is obtained through esterification and pre-polycondensation; then the flame-retardant modification monomer A (obtained in preparation example 1) is added into the pre-polymer, and the desired modified polyester is prepared through polycondensation reaction and final polycondensation reaction, and finally the modified polyester masterbatch is obtained through extrusion granulation and drying.

[0072] The molar ratio of terephthalic acid to ethylene glycol is 1:1.15;

[0073] The molar ratio of terephthalic acid to flame-retardant modification monomer A is 1:0.15;

[0074] The molar ratio of terephthalic acid to catalyst Sb2O3 is 1:0.02;

[0075] The esterification temperature is 230℃, the esterification pressure is 0.2MPa, and the esterification time is 2.0h.

[0076] The pre-polycondensation temperature is 250℃, the pre-polycondensation pressure is -0.01MPa, and the pre-polycondensation time is 45min.

[0077] The polycondensation temperature is 270℃, the polycondensation vacuum degree is 1kPa, and the polycondensation time is 60min.

[0078] The final polycondensation temperature is 280℃, the final polycondensation vacuum degree is 200Pa, and the final polycondensation time is 90min.

[0079] The rotation speed of the extruder is 50r / min, the temperature of the first zone of the extruder is 265℃, the temperature of the second zone is 290℃, the temperature of the third zone is 280℃, and the temperature of the fourth zone is 270℃.

[0080] Step 2: Preparation method of flame-retardant polyester fabric

[0081] 100 parts of the modified polyester masterbatch (obtained in step 1), 15 parts of mica powder (produced by Lingshou County Tuolin Mineral Product Processing Factory, particle size is 10μm, sand content is <3%), 5 parts of antioxidant 1076, 3 parts of anti-ultraviolet agent titanium dioxide, and 10 parts of polyethylene glycol 20000 are mixed uniformly, and then melt spinning is performed on a spinning machine, the spinning temperature in the spinning machine is 265℃, the screw rotation speed is 600r / min, and the winding speed is 1200r / min to obtain polyester fibers, and finally the polyester fibers are spun into flame-retardant polyester fabric by a textile machine.

[0082] Comparative Example 1

[0083] The flame-retardant modified monomer A in Example 1 is replaced by , and other operations and parameters are the same as those in Example 1 to prepare the corresponding polyester fabric.

[0084] Flame-retardant property test

[0085] The flame-retardant properties of the flame-retardant polyester fabrics obtained in Examples 1-3 and Comparative Example 1 are tested, and the test method is as follows:

[0086] Limiting oxygen index: the limiting oxygen index of the polyester fabric is detected according to GB / T 5454-1997 “Textile Burning Property Test Oxygen Index Method”. At the same time, the vertical combustion property UL-94 grade (tested by using CZF-5 type vertical combustion instrument) is used to assist in judgment. In addition, the limiting oxygen index of the fabric after 100 times of washing is tested according to “GB / T 17596-1998 Textile Fabric Burning Test Before Commercial Washing Procedure”. The results are shown in Table 1.

[0087] Table 1: Flame-retardant property test results

[0088]

[0089] As shown in Table 1, after The modified polyester fabric exhibits excellent flame retardant properties, with an initial limiting oxygen index (LOI) of 39.5% and a vertical flammability rating of V0 according to UL-94. Even after 100 washes, the polyester fabric retains a high LIO and demonstrates excellent wash resistance. This is due to two main reasons: firstly, the flame-retardant modifying monomer A of this invention has two carboxyl groups, allowing it to participate in the polycondensation reaction as a polymerizing monomer, thereby embedding the flame-retardant structure into the polymer and giving it excellent wash resistance; secondly, the flame-retardant modifying monomer A of this invention contains triazine and borate ester structures, which themselves possess good flame-retardant properties. Introducing them into the polyester fabric achieves synergistic and efficient flame retardancy. Furthermore, as shown in Example 1 and Comparative Example 1, the introduction of element B significantly improves the flame-retardant properties of the polyester fabric.

[0090] The above embodiments are merely illustrative examples and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing a flame-retardant polyester fabric, comprising the following steps: Step 1: Preparation of modified polyester masterbatch Terephthalic acid, ethylene glycol and catalyst Sb2O3 are added to a reactor and mixed evenly. After esterification and pre-condensation, a prepolymer is obtained. Then, flame-retardant modifying monomer A is added to the prepolymer. After condensation reaction and final condensation reaction, modified polyester is prepared. The modified polyester is extruded, granulated and dried to obtain modified polyester masterbatch. In the formula, the structure of the flame-retardant modifying monomer A is: ; Step 2: Preparation of modified polyester masterbatch By weight, 100 parts of modified polyester masterbatch, 5-15 parts of mica powder, 1-5 parts of antioxidant, 1-3 parts of UV stabilizer, and 8-10 parts of polyethylene glycol 20000 are mixed evenly, and then melt-spun on a spinning machine to obtain polyester fiber. Finally, the polyester fiber is spun into flame-retardant polyester fabric by a textile machine.

2. The preparation method according to claim 1, characterized in that, The antioxidant is selected from one or more of the following: triphenyl phosphite, triphenyl phosphate, antioxidant HP-136, antioxidant 1010, antioxidant 168, antioxidant 1076, and antioxidant 1068.

3. The preparation method according to claim 1, characterized in that, The UV stabilizer is selected from one or more of zirconium oxide, zinc oxide, and titanium dioxide.

4. The preparation method according to claim 1, characterized in that, The molar ratio of terephthalic acid to ethylene glycol is 1:(1~1.5); the molar ratio of terephthalic acid to flame-retardant modified monomer A is 1:(0.05~0.2); and the molar ratio of terephthalic acid to catalyst Sb2O3 is 1:(0.01~0.1).

5. The preparation method according to claim 1, characterized in that: The esterification temperature is 230~250℃, the esterification pressure is 0.1~0.5MPa, and the esterification time is 1~3h; The polycondensation temperature is 270~290℃, the polycondensation vacuum degree is 1~5kPa, and the polycondensation time is 30~60min; The final polycondensation temperature is 280~300℃, the final polycondensation vacuum degree is 100~200Pa, and the final polycondensation time is 60~90min.

6. The preparation method according to claim 1, characterized in that, In step 1, the extruder speed is 20~50 r / min, and the temperature of the first zone of the extruder is 265℃, the second zone temperature is 290℃, the third zone temperature is 280℃, and the fourth zone temperature is 270℃.

7. The preparation method according to claim 1, characterized in that, In step 2, the spinning temperature of the spinning machine is 250~280℃, the screw speed is 500~800 r / min, and the winding speed is 1000~1200 r / min.

8. Flame-retardant polyester fabric prepared by the method according to any one of claims 1-7.

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