Flame-retardant polyester fabric and preparation process thereof

Abstract

The invention belongs to the field of polyester fibers, and particularly relates to a flame-retardant polyester fabric which comprises the following raw materials: 50-70 parts of PET polyester chips, 20-30 parts of modified PET polyester master batches, 1-3 parts of a coupling agent, 1-5 parts of nano silicon dioxide, 0.5-1 part of an antioxidant and 5-10 parts of PEG-400. The polyester fabric prepared by the invention has excellent flame retardant property, the initial limit oxygen index of the polyester fabric reaches 36.8%, and the vertical combustibility UL-94 reaches V0 level; in addition, after 50 times of washing, the limit oxygen index of the fabric is not obviously reduced, and the fabric has good washable performance.

Description

Technical Field

[0001] The invention belongs to the field of polyester fibers, and in particular relates to a flame-retardant polyester fabric and a preparation process thereof. Background Art

[0002] Polyethylene terephthalate (PET) is an aromatic polyester made from terephthalic acid (PTA) and ethylene glycol (EG) through polycondensation. At present, PET polymers have been widely used in the fields of plastics, films and fibers. Especially in the field of fibers, polyester chips made by polycondensation are made into polyester fibers through melt spinning. This fiber has high breaking strength and elastic modulus, moderate resilience, light resistance, heat resistance, corrosion resistance and other excellent properties. Its fabric has excellent wearability, stiffness and wrinkle resistance. Therefore, since the advent of polyester fiber, it has achieved rapid development and has now become the world's largest synthetic fiber.

[0003] Although polyester fiber has many advantages and a huge market, its LOI is low and it is a flammable fiber. In fire accidents, a considerable proportion of fires are caused by fiber textiles catching fire, and the losses caused are becoming more and more serious, which greatly limits its application scope. At the same time, the melting droplet phenomenon produced by polyester during the combustion process is serious. Although the melting droplet can take away some heat from the polymer substrate, which is beneficial to the flame retardancy of polyester, the melting droplet brings more serious disasters: on the one hand, the melting droplet may cause the flame to spread to other places and cause a larger fire; on the other hand, it is easy to cause secondary injuries such as scalds and burns. Based on this, it is urgent to develop more polyester fabrics with excellent flame retardant properties. Summary of the invention

[0004] The object of the present invention is to provide a polyester fabric with excellent flame retardancy and good washability. The present invention is achieved through the following technical solutions:

[0005] A flame retardant polyester fabric, the raw materials of which include, by weight:

[0006] PET polyester chips 50~70 pieces

[0007] Modified PET polyester masterbatch 20-30 parts

[0008] Coupling agent 1-3 parts

[0009] 1-5 parts of nano silicon dioxide

[0010] Antioxidant 0.5-1 part

[0011] PEG-400 5-10 parts

[0012] The modified PET polyester masterbatch is prepared by polymerization of terephthalic acid, ethylene glycol and a modifier in the presence of a catalyst Sb2O3;

[0013] The structural formula of the modifier is:

[0014] In some embodiments, the coupling agent is selected from one or more of KH-550, KH-560, KH-570, KH-792, KH-791, DL-602, and DL-171.

[0015] In some embodiments, the antioxidant is selected from one or more of antioxidant 1010 , antioxidant 168 , antioxidant 1076 , and antioxidant 1068 .

[0016] In some embodiments, the method for preparing the modified PET polyester masterbatch comprises the following steps:

[0017] Terephthalic acid, ethylene glycol, a modifier and a catalyst Sb2O3 in a molar ratio of 1:1:0.5:0.1 are mixed and added into a reactor; the air tightness of the system is checked, nitrogen is introduced to remove the air in the reactor, the temperature is increased and controlled at 220-260°C, and the pressure in the reactor is controlled at 0.2-0.5MPa, and the reaction time is 30-60min; the reaction is continued, the reactor is evacuated, and the temperature is controlled at 260-300°C, and polyester is obtained after 15-30min, which is then extruded, granulated and dried to obtain modified PET polyester masterbatch.

[0018] In some embodiments, the rotation speed of the extruder is 40 r / min, the temperature of the first zone of the extruder is 260°C, the temperature of the second zone is 290°C, the temperature of the third zone is 280°C, and the temperature of the fourth zone is 280°C.

[0019] In some embodiments, the raw materials include, by weight:

[0020] PET polyester chips 50 pieces

[0021] Modified PET polyester masterbatch 30 parts

[0022] Coupling agent DL-602 2 parts

[0023] 3 parts of nano silicon dioxide

[0024] Antioxidant 168 0.5 parts

[0025] PEG-400 10 parts.

[0026] The present invention also provides a preparation process of the flame-retardant polyester fabric, comprising the following steps:

[0027] PET polyester chips, modified PET polyester masterbatch, coupling agent, nano-silica, antioxidant and PEG-400 are mixed evenly, and then melt-spinned on a spinning machine, the spinning temperature in the spinning machine is 220-260° C., the screw speed is 500-800 r / min, and the winding speed is 1000-1200 r / min to obtain polyester fibers; the polyester fibers are spun into flame-retardant polyester fabrics through a spinning machine.

[0028] The present invention has achieved the following beneficial effects:

[0029] 1) The polyester fabric prepared by the present invention has excellent flame retardant properties, with an initial limiting oxygen index of 36.8% and a vertical flammability UL-94 of V0 level; in addition, after 50 times of washing, the limiting oxygen index does not decrease significantly, and the fabric has good washability.

[0030] 2) Modifying agent used in the present invention It also contains three flame retardant elements, B, N, and P. Introducing them into polyester fabrics can achieve synergistic and efficient flame retardancy. In addition, the modifier contains hydroxyl groups at both ends, which can introduce flame retardant molecules into the polymer main chain through polymerization with terephthalic acid, making the polyester fabric have good wash resistance. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] The endpoints and any values ​​of the scope described in the present invention are not limited to the precise scope or value, and these scopes or values ​​should be understood to include values ​​close to these scopes or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be considered as specifically disclosed in this article.

[0033] Preparation Example 1 Synthesis of Modifier

[0034] Step 1: Synthesis of intermediate compound C

[0035]

[0036] Compound A (0.1 mol), triethylamine (0.1 mol) and tetrahydrofuran (100 mL) were added to the reactor and stirred at room temperature until compound A was completely dissolved. Compound B (0.22 mol) and tetrahydrofuran (100 mL) were then mixed evenly and slowly dripped into the reactor at 0°C under a nitrogen environment. The temperature was raised to 60°C and stirred for 10 hours. After the reaction was completed, the filtrate was filtered and washed with water 3 times (200 mL x 3). The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain a crude product. The crude product was separated and purified by column chromatography to obtain intermediate compound C with a yield of 83.6%.

[0037] LC-MS(ESI):[M+H] + =619.3.

[0038] Step 2: Synthesis of modifier

[0039]

[0040] The intermediate compound C (0.1 mol), compound D (0.25 mol), and chloroform (200 mL) were added to the reactor, and the temperature was raised to 60°C and stirred for 12 hours. After the reaction, the mixture was concentrated under reduced pressure to obtain a crude product, which was purified by column chromatography (eluent: dichloromethane: petroleum ether = 1:3) to obtain a white solid modifier with a yield of 67.1%.

[0041] LC-MS(ESI):[M+H] + =705.3.

[0042] 1 H-NMR (500MHz, CDCl3): δ (ppm): 8.60 (s, 2H), 7.87-7.78 (m, 2H), 7.58 (d, 2H), 7.41-7 .35(m,2H),7.25-7.14(m,5H),6.10(t,4H),5.02(s,2H),4.35(t,4H),1.21(s,24H).

[0043] Preparation Example 2 Preparation of modified PET polyester masterbatch

[0044] Terephthalic acid, ethylene glycol, a modifier (obtained in Preparation Example 1) and a catalyst Sb2O3 in a molar ratio of 1:1:0.5:0.1 were mixed and added into a reactor; the air tightness of the system was checked, nitrogen was introduced to remove the air in the reactor, the temperature was raised and controlled at 260°C, and the pressure in the reactor was controlled at 0.5 MPa, and the reaction time was 60 min; the reaction was continued, the reactor was evacuated, and the temperature was controlled at 300°C. After 30 min, polyester was obtained, which was then extruded, granulated and dried to obtain a modified PET polyester masterbatch.

[0045] The rotation speed of the extruder is 40r / min, the temperature of the first zone of the extruder is 260°C, the temperature of the second zone is 290°C, the temperature of the third zone is 280°C, and the temperature of the fourth zone is 280°C.

[0046] Example 1

[0047] A flame retardant polyester fabric, the raw materials of which include, by weight:

[0048] PET polyester chips (viscosity 0.68) 60 parts

[0049] Modified PET polyester masterbatch (obtained in Preparation Example 2) 30 parts

[0050] Coupling agent KH-550 1 part

[0051] 2 parts of nano silicon dioxide

[0052] Antioxidant 1010 1 part

[0053] PEG-400 10 parts

[0054] The preparation method of flame retardant polyester fabric comprises the following steps:

[0055] PET polyester chips, modified PET polyester masterbatch, coupling agent, nano-silica, antioxidant and PEG-400 are mixed evenly, and then melt-spinned on a spinning machine, the spinning temperature in the spinning machine is 260° C., the screw speed is 800 r / min, and the winding speed is 1200 r / min to obtain polyester fibers; the polyester fibers are spun into flame-retardant polyester fabrics through a textile machine.

[0056] Example 2

[0057] A flame retardant polyester fabric, the raw materials of which include, by weight:

[0058] PET polyester chips (viscosity 0.68) 70 parts

[0059] Modified PET polyester masterbatch (obtained in Preparation Example 2) 20 parts

[0060] Coupling agent KH-560 3 parts

[0061] 2 parts of nano silicon dioxide

[0062] Antioxidant 1076 0.5 parts

[0063] PEG-400 8 parts

[0064] The preparation method of flame retardant polyester fabric comprises the following steps:

[0065] PET polyester chips, modified PET polyester masterbatch, coupling agent, nano-silica, antioxidant and PEG-400 are mixed evenly, and then melt-spinned on a spinning machine, the spinning temperature in the spinning machine is 260° C., the screw speed is 800 r / min, and the winding speed is 1200 r / min to obtain polyester fibers; the polyester fibers are spun into flame-retardant polyester fabrics through a textile machine.

[0066] Example 3

[0067] A flame retardant polyester fabric, the raw materials of which include, by weight:

[0068] PET polyester chips (viscosity 0.68) 50 parts

[0069] Modified PET polyester masterbatch (obtained in Preparation Example 2) 30 parts

[0070] Coupling agent DL-602 2 parts

[0071] 3 parts of nano silicon dioxide

[0072] Antioxidant 168 0.5 parts

[0073] PEG-400 10 parts

[0074] The preparation method of flame retardant polyester fabric comprises the following steps:

[0075] PET polyester chips, modified PET polyester masterbatch, coupling agent, nano-silica, antioxidant and PEG-400 are mixed evenly, and then melt-spinned on a spinning machine, the spinning temperature in the spinning machine is 260° C., the screw speed is 800 r / min, and the winding speed is 1200 r / min to obtain polyester fibers; the polyester fibers are spun into flame-retardant polyester fabrics through a textile machine.

[0076] Comparative Example 1

[0077] The modifier in Preparation Example 2 is replaced by a known Other operations and conditions were the same as those in Preparation Example 2 to obtain modified PET polyester masterbatch B.

[0078] Then, on the basis of Example 1, the modified PET polyester masterbatch was replaced with the modified PET polyester masterbatch B, and the other components and preparation methods were the same as those in Example 1.

[0079] Flame retardant performance determination:

[0080] The flame retardant properties of the polyester fabrics obtained in Examples 1-3 and Comparative Example 1 were measured respectively, and the test methods were as follows:

[0081] Limiting oxygen index: According to GB / T 5454-1997 "Textile Combustion Performance Test Oxygen Index Method", the limiting oxygen index of polyester fabrics is tested. At the same time, the vertical flammability UL-94 grade (tested by CZF-5 vertical combustion instrument) is used to assist in judgment.

[0082] Washing is carried out under standard atmospheric conditions (20±2°C, 65±5%RH), and washing in clean water for 30 minutes is counted as one wash.

[0083] The results are shown in Table 1.

[0084] Table 1 Flame retardant performance test results

[0085]

[0086] As can be seen from the above table, the polyester fabric prepared by the present invention has excellent flame retardant properties. The limiting oxygen index LOI is one of the important indicators of flame retardant materials. Its initial limiting oxygen index reaches 36.8%, and the vertical flammability UL-94 reaches V0 level; in addition, after 50 times of washing, its limiting oxygen index does not decrease significantly, and it has good washing resistance. The main reasons are: 1) The modifier screened by the present invention It also contains three flame retardant elements, B, N, and P, which can be introduced into polyester fabrics to achieve synergistic and efficient flame retardancy; 2) The modifier of the present invention contains hydroxyl groups at both ends, and flame retardant molecules are introduced into the polymer main chain through polymerization with terephthalic acid, so that the polyester fabric has good wash resistance.

[0087] The above embodiments are merely examples for clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A flame retardant polyester fabric, the raw materials of which include, by weight: The modified PET polyester masterbatch is prepared by polymerization of terephthalic acid, ethylene glycol and a modifier in the presence of a catalyst Sb2O3; The structural formula of the modifier is:

2. The flame retardant polyester fabric according to claim 1, characterized in that: The coupling agent is selected from one or more of KH-550, KH-560, KH-570, KH-792, KH-791, DL-602 and DL-171.

3. The flame retardant polyester fabric according to claim 1, characterized in that: The antioxidant is selected from one or more of antioxidant 1010 , antioxidant 168 , antioxidant 1076 and antioxidant 1068 .

4. The flame retardant polyester fabric according to claim 1, characterized in that: The preparation method of the modified PET polyester masterbatch comprises the following steps: Terephthalic acid, ethylene glycol, a modifier and a catalyst Sb2O3 in a molar ratio of 1:1:0.5:0.1 are mixed and added into a reactor; the air tightness of the system is checked, nitrogen is introduced to remove the air in the reactor, the temperature is increased and controlled at 220-260°C, and the pressure in the reactor is controlled at 0.2-0.5MPa, and the reaction time is 30-60min; the reaction is continued, the reactor is evacuated, and the temperature is controlled at 260-300°C, and polyester is obtained after 15-30min, which is then extruded, granulated and dried to obtain modified PET polyester masterbatch.

5. The flame retardant polyester fabric according to claim 4, characterized in that: The rotation speed of the extruder is 40r / min, the temperature of the first zone of the extruder is 260°C, the temperature of the second zone is 290°C, the temperature of the third zone is 280°C, and the temperature of the fourth zone is 280°C.

6. The flame retardant polyester fabric according to claim 1, characterized in that: By weight, the raw materials include:

7. The flame retardant polyester fabric according to claim 1, characterized in that: By weight, the raw materials include:

8. A process for preparing the flame-retardant polyester fabric according to any one of claims 1 to 7, comprising the following steps: PET polyester chips, modified PET polyester masterbatch, coupling agent, nano-silica, antioxidant and PEG-400 are mixed evenly, and then melt-spinned on a spinning machine, the spinning temperature in the spinning machine is 220-260° C., the screw speed is 500-800 r / min, and the winding speed is 1000-1200 r / min to obtain polyester fibers; the polyester fibers are spun into flame-retardant polyester fabrics through a spinning machine.

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