Flame-retardant polyethylene non-woven sheet as well as preparation method and application thereof

Abstract

The invention discloses a flame-retardant polyethylene non-woven sheet as well as a preparation method and application of the flame-retardant polyethylene non-woven sheet, and belongs to the technical field of high polymer materials. Comprising the following components in parts by weight: 60-80 parts of first high-density polyethylene resin, 5-12 parts of polyetherimide, 2-8 parts of a sulfonate flame retardant, 2-7 parts of fumed silica, 2-6 parts of a composite compatilizer, 1-4 parts of polyethylene glycol and 0.1-1 part of an auxiliary agent. The high-density polyethylene resin is used as a matrix, under the combined action of the polyetherimide, the sulfonate flame retardant, the fumed silica, the composite compatilizer, the polyethylene glycol and the auxiliaries, the flame retardant property of the flame-retardant polyethylene non-woven sheet is remarkably improved, and the flame-retardant polyethylene non-woven sheet has a wide application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a flame-retardant polyethylene nonwoven sheet and a preparation method and application thereof. Background Art

[0002] Flash spinning to prepare nonwoven materials refers to the process of releasing polymer raw materials to room temperature and pressure in an instant under high temperature and high pressure to form spindle fiber membranes. Compared with the same type of polymer products prepared under traditional processes, flash spinning fiber membranes have higher mechanical strength, smaller weight, more uniform fiber distribution, and better air permeability. They are very suitable for preparing products such as filter materials, medical supplies (such as masks), textile reinforcement materials, industrial protective clothing, etc.

[0003] The preparation of nonwoven materials by flash spinning has the following characteristics and advantages: 1. Controllable fiber diameter: Ultrafine fibers with diameters at the micron level can be prepared, and these fibers have a high specific surface area and specific physical properties. 2. High strength and high performance: Because the fibers solidify rapidly during the formation process, they have excellent mechanical properties and durability. 3. Efficient production: The production process is simple and efficient, suitable for large-scale industrial production. It is widely used in medical and industrial protection, medical packaging, industrial packaging, building materials, clothing, household materials, and printing and cultural creation. In view of its wide range of application scenarios, flash non-woven fabrics with flame retardant properties are developed through flash spinning to meet the challenges in different application scenarios.

[0004] In view of this, this application is filed. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a flame-retardant polyethylene non-woven sheet and its preparation method and application. The flame-retardant polyethylene non-woven sheet has excellent flame retardant properties, so that it can be used to prepare flame-retardant non-woven materials, significantly improve the flame retardant properties of non-woven materials, and has broad application prospects.

[0006] To achieve the above-mentioned purpose, in the first aspect of the present application, the present application provides a flame-retardant polyethylene non-woven sheet, comprising the following components in parts by weight: 60 to 80 parts of a first high-density polyethylene resin, 5 to 12 parts of polyetherimide, 2 to 8 parts of a sulfonate flame retardant, 2 to 7 parts of fumed silica, 2 to 6 parts of a composite compatibilizer, 1 to 4 parts of polyethylene glycol, and 0.1 to 1 part of an auxiliary agent.

[0007] The present invention creatively combines the above-mentioned raw materials, takes high-density polyethylene resin as the matrix, and under the joint action of polyetherimide, sulfonate flame retardant, fumed silica, composite compatibilizer, polyethylene glycol and additives, significantly improves the flame retardant properties of the flame-retardant polyethylene non-woven sheet, and has broad application prospects.

[0008] Among them, polyetherimide has a high oxygen index and high thermal stability, can maintain structural stability at high temperatures, and is not easy to decompose. During the combustion process, polyetherimide is easy to form a carbon layer, which can block the transfer of heat and oxygen, thereby slowing down the combustion rate. At the same time, the pyrolysis products of polyetherimide have a certain effect on extinguishing the flame, which can effectively interrupt the chain reaction and effectively reduce the combustion rate. Fumed silica can effectively diffuse and adsorb free radicals and reactive molecules in combustion, and can form a protective layer at high temperatures to block the exchange of substances and energy between polymer materials and the outside world, inhibiting the combustion. Sulfonate flame retardants decompose at high temperatures to release smokeless, non-toxic gas-phase flame retardants such as phosphorus oxides, which can effectively inhibit combustion and interfere with the combustion chain reaction, and prevent the continuous combustion reaction, thereby greatly reducing the flame propagation speed and heat release rate of the material. The present invention uses polyetherimide, sulfonate flame retardant and fumed silica as main flame retardant components. Under the synergistic effect of the three, the thermal stability of the polyethylene composite material is effectively improved. The sulfonate flame retardant and polyetherimide can promote the carbonization of polymer molecules and enhance the thermal stability and flame retardant performance of the material; while the fumed silica can capture free radicals and form a protective layer to further inhibit the combustion. The three work together to effectively reduce the combustion speed, effectively inhibit the combustion interference combustion chain reaction, and effectively improve the flame retardant performance of the flame retardant polyethylene non-woven sheet.

[0009] Among them, the amount of the first high-density polyethylene resin is 60 to 80 parts, for example, it can be 60 parts, 62 parts, 65 parts, 66 parts, 68 parts, 70 parts, 72 parts, 74 parts, 75 parts, 76 parts, 78 parts, 80 parts or a range consisting of any two of the values.

[0010] The amount of polyetherimide used is 5 to 12 parts, for example, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts or a range consisting of any two of these values.

[0011] The amount of the sulfonate flame retardant is 2 to 8 parts, for example, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts or a range consisting of any two of these values.

[0012] The amount of fumed silica used is 2 to 7 parts, for example, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts or a range consisting of any two of these values.

[0013] The amount of the composite compatibilizer is 2 to 6 parts, for example, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts or a range consisting of any two of these values.

[0014] The amount of polyethylene glycol used is 1 to 4 parts, for example, 1 part, 2 parts, 3 parts, 4 parts or a range consisting of any two of these values.

[0015] The dosage of the auxiliary agent is 0.1 to 1 part, for example, it can be 0.1 part, 0.2 part, 0.4 part, 0.5 part, 0.6 part, 0.8 part, 1 part or a range consisting of any two of the values.

[0016] Preferably, the flame-retardant polyethylene non-woven sheet comprises the following components in parts by weight: 65 to 73.5 parts of a first high-density polyethylene resin, 8 to 10 parts of polyetherimide, 4 to 6 parts of a sulfonate flame retardant, 4 to 5 parts of fumed silica, 4 to 5 parts of a composite compatibilizer, 2 to 3 parts of polyethylene glycol, and 0.5 to 0.8 parts of an auxiliary agent, which further improves the flame retardant properties. In particular, when the amount of each raw material is within this range, the compatibility between the components is better, and the flame retardant properties can be more significantly improved.

[0017] Preferably, the first high-density polyethylene has a melt flow rate greater than or equal to 1 g / 10 min and less than or equal to 12 g / 10 min at 190 ° C and 2.16 kg load according to the ISO1133-2011 method, for example, it can be 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, 5 g / 10 min, 6 g / 10 min, 7 g / 10 min, 8 g / 10 min, 9 g / 10 min, 10 g / 10 min, 11 g / 10 min, 12 g / 10 min or a range consisting of any two of them.

[0018] Preferably, the melt flow rate of the first high-density polyethylene at 190°C and 2.16kg load is greater than or equal to 4g / 10min and less than or equal to 7g / 10min. The selection of the melt flow rate of the first high-density polyethylene will affect the compatibility between the components as well as the processability and fluidity. By selecting a melt flow rate within this range, the flame retardant properties can be further improved.

[0019] Preferably, the polyetherimide has a melt flow rate of greater than or equal to 5 g / 10 min and less than or equal to 24 g / 10 min at 337 ° C and 6.6 kg load according to the ISO1133-2011 method, for example, it can be 5 g / 10 min, 6 g / 10 min, 8 g / 10 min, 10 g / 10 min, 12 g / 10 min, 15 g / 10 min, 18 g / 10 min, 22 g / 10 min, 22 g / 10 min, 24 g / 10 min or a range consisting of any two of the values.

[0020] Preferably, the sulfonate flame retardant includes at least one of potassium perfluorobutyl sulfonate, potassium 3-phenylsulfonylbenzenesulfonate, diphenyl sulfone-3-sulfonate, potassium benzenesulfonylbenzenesulfonate, and sodium p-toluenesulfonate.

[0021] Preferably, the specific surface area of ​​the fumed silica is greater than or equal to 200 m 2 / g and less than or equal to 450m 2 / g, for example, it can be 200m 2 / g, 220m 2 / g, 250m 2 / g, 280m 2 / g、300m 2 / g, 350m 2 / g, 380m 2 / g, 400m 2 / g, 420m 2 / g, 450m 2 / g or a range consisting of any two values ​​therein.

[0022] The specific surface area of ​​the fumed silica is

[0023] Preferably, the molecular weight of the polyethylene glycol is greater than or equal to 200 and less than or equal to 1000, for example, it can be 200, 300, 400, 500, 600, 700, 800, 900, 1000 or a range consisting of any two of these values.

[0024] Preferably, the composite compatibilizer comprises the following components in parts by weight: 85-87 parts of a second high-density polyethylene resin, 4-6 parts of maleic anhydride, 4-6 parts of glycidyl methacrylate, 2-4 parts of styrene, and 0.5-2 parts of an initiator.

[0025] The present invention creatively uses a second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, and styrene as a composite compatibilizer to form a maleic anhydride-grafted high-density polyethylene resin and a glycidyl methacrylate-grafted high-density polyethylene, which can significantly improve the compatibility of the system, promote the spinning process, avoid agglomeration, and significantly improve the flame retardant properties of the flame-retardant polyethylene non-woven sheet.

[0026] Preferably, the preparation method of the composite compatibilizer comprises the following steps: uniformly mixing the second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and an initiator, and melt-extruding and granulating to obtain the composite compatibilizer.

[0027] Preferably, the second high-density polyethylene has a melt flow rate greater than or equal to 1 g / 10 min and less than or equal to 12 g / 10 min at 190 ° C and 2.16 kg load according to the ISO1133-2011 method, for example, it can be 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, 5 g / 10 min, 6 g / 10 min, 7 g / 10 min, 8 g / 10 min, 9 g / 10 min, 10 g / 10 min, 11 g / 10 min, 12 g / 10 min or a range consisting of any two of them.

[0028] Preferably, the second high-density polyethylene has a melt flow rate at 190° C. and a load of 2.16 kg of 4 g / 10 min or more and 7 g / 10 min or less.

[0029] Preferably, the initiator includes at least one of azobisisobutyronitrile, potassium persulfate, and ammonium persulfate.

[0030] Preferably, the auxiliary agent includes at least one of an antioxidant and a lubricant.

[0031] Preferably, the lubricant includes at least one of a silicone lubricant, an amide lubricant, and a stearic acid lubricant.

[0032] Preferably, the antioxidant includes at least one of a thioester antioxidant, a hindered phenol antioxidant, a hydroxylamine antioxidant, a phosphite antioxidant, and a phosphate antioxidant.

[0033] Preferably, the thioester antioxidant includes at least one of dialkyl thiodipropionate or pentaerythritol tetrakis (3-lauryl thiopropionate).

[0034] Preferably, the hindered phenol antioxidant includes at least one of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] pentaerythritol ester, tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate, 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester, ethylene bis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate] or 3,9-bis[1,1-dimethyl-2-[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane.

[0035] Preferably, the hydroxylamine antioxidant includes bis(octadecyl)hydroxylamine.

[0036] Preferably, the phosphite antioxidant includes at least one of tris(2,4-di-tert-butylphenyl)phosphite and pentaerythritol bis(2,4-tert-butylphenyl)phosphite.

[0037] Preferably, the phosphate antioxidant includes bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphate.

[0038] Preferably, the weight of the flame retardant polyethylene nonwoven sheet is less than or equal to 110 g / m 2 The limiting oxygen index of the flame retardant polyethylene nonwoven sheet is greater than or equal to 33%, and the flame retardant protection rate of the flame retardant polyethylene nonwoven sheet is above 39%.

[0039] Preferably, the weight of the flame retardant polyethylene nonwoven sheet is less than or equal to 100 g / m 2 .

[0040] Preferably, the weight of the flame retardant polyethylene nonwoven sheet is 50 to 100 g / m 2 .

[0041] In a second aspect of the present application, the present application provides a method for preparing a flame retardant polyethylene nonwoven sheet, comprising the following steps:

[0042] The components are mixed uniformly to obtain a mixture, and the mixture is added into a reaction kettle containing a solvent, and then heated and nitrogen is introduced so that the temperature in the reaction kettle is greater than or equal to 200° C. and less than or equal to 230° C., and the pressure is greater than or equal to 10 MPa and less than or equal to 12 MPa, to obtain a spinning solution;

[0043] The spinning solution is placed in a flash spinning device for spinning and received by a receiving device. The received product is cold pressed and hot rolled to obtain a flame-retardant polyethylene nonwoven sheet.

[0044] Preferably, the boiling point of the solvent is ≤ 100°C.

[0045] More preferably, the solvent includes at least one of benzene, toluene, butane, pentene, n-hexane, heptane, octane, cyclohexane, dichloromethane, carbon tetrachloride, chloroform, chloromethane, chlorofluoromethane, and ethyl chloride.

[0046] More preferably, the mass ratio of the mixture to the solvent in the spinning solution is (10-30):(70-90).

[0047] More preferably, the flash spinning device is prepared using the production equipment 300 used by the inventor in the prior research and development technology CN115323628B.

[0048] It should be noted that the products of the present application are not limited to the production of the above-mentioned production equipment. Technical personnel in this field may also adopt other types of flash production equipment to produce products according to actual needs, as long as products with the same technical characteristics and technical effects can be prepared.

[0049] In the third aspect of the present application, the present application provides an application of a flame-retardant polyethylene non-woven sheet in the preparation of home and decoration materials, personal protective equipment, transportation materials, construction and engineering materials, industrial application materials, military and defense materials, electronic and electrical product materials, and fire protection materials.

[0050] Exemplarily, the home furnishing and decoration materials include mattresses, furniture fabrics, wallpapers, wall decorations, ceiling decorations, curtains, carpets, floor coverings, home clothes, etc.

[0051] Exemplarily, the personal protective equipment includes protective clothing and work clothes, such as firefighter clothing, welding worker clothing, etc.; the personal protective equipment also includes medical textiles, such as surgical drapes, isolation clothing, etc.

[0052] Exemplarily, the transportation materials include vehicle interior materials, such as seats, door panels, ceilings, etc.; the transportation materials also include aircraft interior materials, such as seats, partitions, luggage compartment linings, etc.

[0053] Exemplarily, the building and engineering materials include building partition and sound insulation materials, fireproof and heat-insulating materials, waterproof and breathable membranes, cable and pipe covering materials, etc.

[0054] Exemplarily, the industrial application materials include industrial wiping cloths, industrial oil absorbing materials, and the like.

[0055] Exemplarily, the military and defense materials include tents and shade materials, protective gear and equipment coverings, and the like.

[0056] Exemplarily, the electronic and electrical product materials include insulating and heat-insulating materials, equipment internal protective layer materials, etc.

[0057] Exemplarily, the fire protection field materials include smoke and flame barrier curtains, fire escape devices and path indication materials, fire protection clothing, light box films, etc.

[0058] Among them, the sources of raw materials in the examples and comparative examples of the present application are as follows:

[0059] HDPE-1 (high-density polyethylene resin-1): The melt flow rate at 190°C and 2.16 kg is 7 g / 10 min, Braskem, brand number PESHC7260.

[0060] HDPE-2 (high-density polyethylene resin-2): melt flow rate at 190°C, 2.16 kg is 4 g / 10 min, ExxonMobil, brand HMA 014.

[0061] HDPE-3 (high-density polyethylene resin-3): The melt flow rate at 190°C and 2.16kg is 12g / 10min, produced by Sinopec, with the brand name HDPE FMA016.

[0062] HDPE-4 (high-density polyethylene resin-4): The melt flow rate at 190°C and 2.16kg is 1g / 10min, Sinopec, brand 5000S.

[0063] PEI-1 (polyetherimide-1): melt flow rate at 337°C and 6.6kg load is 18g / 10min, Saudi Arabian base, brand ULTEM TM SF2360 resin.

[0064] PEI-2 (polyetherimide-2): melt flow rate at 337°C and 6.6kg load is 10g / 10min, Saudi Arabian base, brand ULTEM TM 2312resin.

[0065] PEI-3 (polyetherimide-3): melt flow rate at 337°C and 6.6kg load is 5g / 10min, Saudi Arabian base, brand ULTEM TM 2300F resin.

[0066] PEI-4 (polyetherimide-4): melt flow rate at 337°C and 6.6kg load is 24g / 10min, Saudi Arabian base, brand ULTEM TM ATX200F resin.

[0067] Sulfonate flame retardant-1: Potassium 3-phenylsulfonylbenzenesulfonate, commonly available in the market.

[0068] Sulfonate flame retardant-2: potassium perfluorobutyl sulfonate, commonly available in the market.

[0069] Fumed silica-1: Specific surface area is 380m 2 / g, Chuangfu Nano, brand HL-380.

[0070] Fumed silica-2: Specific surface area is 300m 2 / g, Chuangfu Nano, brand HL-300.

[0071] Fumed silica-3: Specific surface area is 200m 2 / g, Chuangfu Nano, brand HL-200.

[0072] Fumed silica-4: Specific surface area is 450m 2 / g, Chuangfu Nano, brand HL-450.

[0073] Polyethylene glycol-1: molecular weight 400, PEG-400, Guangzhou Aoshike New Materials.

[0074] Polyethylene glycol-2: molecular weight is 800, PEG-800, Guangzhou Aoshike New Materials.

[0075] Polyethylene glycol-3: molecular weight is 200, PEG-200, Guangzhou Oshiko New Materials.

[0076] Polyethylene glycol-4: molecular weight is 1000, PEG-1000, Guangzhou Aoshike New Materials.

[0077] Antioxidant: Antioxidant 1010, commonly available in the market.

[0078] Maleic anhydride, glycidyl methacrylate, styrene, and azobisisobutyronitrile are all commercially available.

[0079] The preparation method of the composite compatibilizer-1 comprises the following steps:

[0080] (1) The following raw materials were weighed in parts by weight: 86 parts of HDPE-1 (high-density polyethylene resin-1), 5 parts of maleic anhydride, 5 parts of glycidyl methacrylate, 3 parts of styrene, and 1 part of azobisisobutyronitrile.

[0081] (2) The second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and azobisisobutyronitrile are mixed uniformly and put into a twin-screw extruder (with a length-to-diameter ratio of 40:1) for melt mixing. The processing temperatures are: 160°C for zone 1, 170°C for zone 2, 180°C for zone 3, 200°C for zone 4, 210°C for zone 5, 210°C for zone 6, 210°C for zone 7, 220°C for zone 8 and 220°C for zone 9. Extrusion granulation is performed to obtain a composite compatibilizer-1.

[0082] The preparation method of composite compatibilizer-2 comprises the following steps:

[0083] (1) The following raw materials were weighed in parts by weight: 87 parts of HDPE-1 (high-density polyethylene resin-1), 4 parts of maleic anhydride, 6 parts of glycidyl methacrylate, 2 parts of styrene, and 1 part of azobisisobutyronitrile.

[0084] (2) The second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and azobisisobutyronitrile are mixed uniformly and put into a twin-screw extruder (with a length-to-diameter ratio of 40:1) for melt mixing. The processing temperatures are: 160°C for zone 1, 170°C for zone 2, 180°C for zone 3, 200°C for zone 4, 210°C for zone 5, 210°C for zone 6, 210°C for zone 7, 220°C for zone 8 and 220°C for zone 9. Extrusion granulation is performed to obtain composite compatibilizer-2.

[0085] The preparation method of composite compatibilizer-3 comprises the following steps:

[0086] (1) The following raw materials were weighed in parts by weight: 85 parts of HDPE-1 (high-density polyethylene resin-1), 6 parts of maleic anhydride, 2 parts of glycidyl methacrylate, 4 parts of styrene, and 2 parts of azobisisobutyronitrile.

[0087] (2) The second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and azobisisobutyronitrile are mixed uniformly and put into a twin-screw extruder (with a length-to-diameter ratio of 40:1) for melt mixing. The processing temperatures are: 160°C for zone 1, 170°C for zone 2, 180°C for zone 3, 200°C for zone 4, 210°C for zone 5, 210°C for zone 6, 210°C for zone 7, 220°C for zone 8 and 220°C for zone 9. Extrusion granulation is performed to obtain composite compatibilizer-3.

[0088] The preparation method of composite compatibilizer-4 comprises the following steps:

[0089] (1) The following raw materials were weighed in parts by weight: 86 parts of HDPE-1 (high-density polyethylene resin-1), 2 parts of maleic anhydride, 8 parts of glycidyl methacrylate, 3 parts of styrene, and 1 part of azobisisobutyronitrile.

[0090] (2) The second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and initiator are mixed uniformly and put into a twin-screw extruder (with a length-to-diameter ratio of 40:1) for melt mixing. The processing temperatures are: 160°C for zone 1, 170°C for zone 2, 180°C for zone 3, 200°C for zone 4, 210°C for zone 5, 210°C for zone 6, 210°C for zone 7, 220°C for zone 8 and 220°C for zone 9. Extrusion granulation is performed to obtain composite compatibilizer-4.

[0091] The preparation method of the composite compatibilizer-5 comprises the following steps:

[0092] (1) The following raw materials were weighed in parts by weight: 86 parts of HDPE-1 (high-density polyethylene resin-1), 8 parts of maleic anhydride, 2 parts of glycidyl methacrylate, 3 parts of styrene, and 1 part of azobisisobutyronitrile.

[0093] (2) The second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and azobisisobutyronitrile are mixed uniformly and put into a twin-screw extruder (with a length-to-diameter ratio of 40:1) for melt mixing. The processing temperatures are: 160°C for zone 1, 170°C for zone 2, 180°C for zone 3, 200°C for zone 4, 210°C for zone 5, 210°C for zone 6, 210°C for zone 7, 220°C for zone 8 and 220°C for zone 9. Extrusion granulation is performed to obtain a composite compatibilizer-5.

[0094] The preparation method of composite compatibilizer-6 comprises the following steps:

[0095] (1) The following raw materials were weighed in parts by weight: 86 parts of HDPE-1 (high-density polyethylene resin-1), 10 parts of maleic anhydride, 3 parts of styrene, and 1 part of azobisisobutyronitrile.

[0096] (2) The second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and azobisisobutyronitrile are mixed uniformly and put into a twin-screw extruder (with a length-to-diameter ratio of 40:1) for melt mixing. The processing temperatures are: 160°C for zone 1, 170°C for zone 2, 180°C for zone 3, 200°C for zone 4, 210°C for zone 5, 210°C for zone 6, 210°C for zone 7, 220°C for zone 8 and 220°C for zone 9. Extrusion granulation is performed to obtain composite compatibilizer-6.

[0097] The preparation method of composite compatibilizer-7 comprises the following steps:

[0098] (1) The following raw materials were weighed in parts by weight: 86 parts of HDPE-1 (high-density polyethylene resin-1), 10 parts of glycidyl methacrylate, 3 parts of styrene, and 1 part of azobisisobutyronitrile.

[0099] (2) The second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and azobisisobutyronitrile are mixed uniformly and put into a twin-screw extruder (with a length-to-diameter ratio of 40:1) for melt mixing. The processing temperatures are: 160°C for zone 1, 170°C for zone 2, 180°C for zone 3, 200°C for zone 4, 210°C for zone 5, 210°C for zone 6, 210°C for zone 7, 220°C for zone 8 and 220°C for zone 9. Extrusion granulation is performed to obtain composite compatibilizer-7.

[0100] The beneficial effects of the present invention are: (1) The present invention uses high-density polyethylene resin as a matrix, and under the joint action of polyetherimide, sulfonate flame retardant, fumed silica, composite compatibilizer, polyethylene glycol, and additives, significantly improves the flame retardant properties of flame-retardant polyethylene non-woven sheets, and has broad application prospects.

[0101] (2) The present invention uses polyetherimide, sulfonate flame retardant and fumed silica as the main flame retardant components. Under the synergistic effect of the three, the thermal stability of the flame retardant polyethylene non-woven sheet is effectively improved. Sulfonate flame retardant and polyetherimide can promote the carbonization of polymer molecules and enhance the thermal stability and flame retardant properties of the material; while fumed silica can capture free radicals and form a protective layer to further inhibit the combustion. The three work together to effectively reduce the combustion rate, effectively inhibit the combustion and interfere with the combustion chain reaction, and effectively improve the flame retardant properties of the flame retardant polyethylene non-woven sheet. DETAILED DESCRIPTION

[0102] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0103] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0104] In this application, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0105] In the present application, there is no particular limitation on the specific dispersion and stirring treatment methods.

[0106] Unless otherwise specified, the components, raw materials or instruments used in the embodiments and comparative examples of the present invention are all commercially available raw materials or instruments, and the components and raw materials used in each parallel experiment are all of the same kind.

[0107] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0108] Examples 1 to 20, Comparative Examples 1 to 8

[0109] The formulations of the flame-retardant polyethylene nonwoven sheets of Examples 1 to 20 and Comparative Examples 1 to 8 are shown in Table 1 and Table 2 (all in the tables are parts by weight).

[0110] Table 1

[0111]

[0112] Table 2

[0113]

[0114]

[0115] Embodiment 21

[0116] A method for preparing a flame retardant polyethylene nonwoven sheet comprises the following steps:

[0117] (1) Preparation of masterbatch: The components are uniformly mixed according to the formula ratio of the flame-retardant polyethylene nonwoven sheet, and put into a twin-screw extruder (with a length-to-diameter ratio of 40:1) for melt mixing. The processing temperatures are: 160°C for zone 1, 170°C for zone 2, 180°C for zone 3, 200°C for zone 4, 210°C for zone 5, 210°C for zone 6, 210°C for zone 7, 220°C for zone 8, and 220°C for zone 9. Extrusion granulation is performed to obtain masterbatch.

[0118] (2) Preparation of spinning solution: The masterbatch was transferred to a reactor containing a mixed solvent of difluorochloromethane and tetrafluorodichloroethane (15%:85%), preheated to 180°C, then nitrogen was introduced and pressurized to 12 MPa, and finally heated to 225°C and stirred in a closed manner for 2 h. After the temperature stabilized, a spinning solution was obtained, in which the mass ratio of the solid phase to the liquid phase was 15:85;

[0119] (3) Preparation of flash nonwoven fabric: Referring to CN115323628B, a flash spinning device 300 was used to transfer the spinning solution to the nozzle for spray spinning, and then the spinning solution was refracted and reflected by a rotating filament separator to form a mesh sheet and laid on a moving mesh curtain. The speed of the ejected air flow was 12000 m / min, the frequency of the rotating filament separator was 35 Hz, and the forward speed of the moving mesh curtain was 45 m / min. The collected mesh sheet was cold pressed at a pressure of 0.8 MPa and hot rolled at a pressure of 140°C and 3.2 MPa (the hot rolling roller surface speed was 50 m / min) to obtain a flame-retardant polyethylene nonwoven sheet with a gram weight of 80 g / m 2 .

[0120] Test Case

[0121] Examples 1 to 20 and Comparative Examples 1 to 8 were prepared into flame-retardant polyethylene nonwoven sheets according to the method of Example 21 for testing.

[0122] 1. Refer to GB / T 5454-1997 "Textile Combustion Performance Test Oxygen Index Method" for the limit oxygen index limit test of flame retardant polyethylene non-woven sheet. The test results are shown in Table 1.

[0123] 2. Test the flame retardant grade according to UL-94V.

[0124] 3. Combustion performance: Tested in accordance with GB / T 5455-2014, with a total radial length of 300 mm for the test sample.

[0125] Table 3

[0126]

[0127]

[0128]

[0129]

[0130]

[0131] The damaged length is the average value of 5 tests for each embodiment, and the flame retardant protection rate = (1-damaged length / total radial length of the test sample)*100%.

[0132] It can be seen from Table 1 that the flame-retardant polyethylene non-woven sheet of the present invention has excellent flame retardant properties, which can significantly improve the flame retardant properties of non-woven materials. Among them, the non-woven material prepared from the flame-retardant polyethylene non-woven sheet of the present invention has a limiting oxygen index of ≥33%, a flame retardant grade of V-1 or above, and a flame retardant protection rate of ≥39%, and has broad application prospects.

[0133] By comparing Example 2 with Comparative Examples 1 to 8, it can be seen that the polyetherimide, sulfonate flame retardant and fumed silica of the present invention have a significant synergistic effect in flame retardancy. Under the synergistic effect of the three, the flame retardant effect is significantly improved. The lack of any one of them will lead to a significant decrease in the flame retardant effect.

[0134] Comparative Examples 1 to 4 show that the flame retardant properties are further improved by controlling the amount of each raw material to: 65 to 73.5 parts of a first high-density polyethylene resin, 8 to 10 parts of polyetherimide, 4 to 6 parts of a sulfonate flame retardant, 4 to 5 parts of fumed silica, 4 to 5 parts of a composite compatibilizer, 2 to 3 parts of polyethylene glycol, and 0.5 to 0.8 parts of an auxiliary agent.

[0135] By comparing Examples 2 and 5 with Examples 6 to 7, it can be seen that the present invention further improves the flame retardant properties by controlling the melt flow rate of HDPE at 190° C. and 2.16 kg load to be greater than or equal to 4 g / 10 min and less than or equal to 7 g / 10 min.

[0136] By comparing Examples 2 and 8 with Examples 9 to 10, it can be seen that the present invention further improves the flame retardant properties by controlling the melt flow rate of polyetherimide at 337° C. and 6.6 kg load to be greater than or equal to 10 g / 10 min and less than or equal to 18 g / 10 min.

[0137] Comparing Examples 2 and 11 with Examples 12 to 13, it can be seen that the present invention controls the specific surface area of ​​the fumed silica to be greater than or equal to 300 m 2 / g and less than or equal to 3800m 2 / g, further improving the flame retardant properties.

[0138] By comparing Example 2 with Examples 15 to 20, it can be seen that the flame retardant performance is significantly improved by adopting the specific composite compatibilizer of the present invention.

[0139] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A flame retardant polyethylene nonwoven sheet, characterized in that: The invention comprises the following components in parts by weight: 60 to 80 parts of a first high-density polyethylene resin, 5 to 12 parts of polyetherimide, 2 to 8 parts of a sulfonate flame retardant, 2 to 7 parts of gas-phase silica, 2 to 6 parts of a composite compatibilizer, 1 to 4 parts of polyethylene glycol and 0.1 to 1 part of an auxiliary agent.

2. The flame retardant polyethylene nonwoven sheet according to claim 1, characterized in that: The melt flow rate of the first high-density polyethylene at 190° C. and 2.16 kg load is greater than or equal to 1 g / 10 min and less than or equal to 12 g / 10 min; The polyetherimide has a melt flow rate of greater than or equal to 5 g / 10 min and less than or equal to 24 g / 10 min at 337° C. and a load of 6.6 kg.

3. The flame retardant polyethylene nonwoven sheet according to claim 1, characterized in that: The sulfonate flame retardant includes at least one of potassium perfluorobutyl sulfonate, potassium 3-phenylsulfonylbenzenesulfonate, diphenyl sulfone-3-sulfonate, potassium benzenesulfonylbenzenesulfonate, and sodium p-toluenesulfonate.

4. The flame retardant polyethylene nonwoven sheet according to claim 1, characterized in that: The specific surface area of ​​the fumed silica is greater than or equal to 200 m 2 / g and less than or equal to 450m 2 / g; and / or The molecular weight of the polyethylene glycol is greater than or equal to 200 and less than or equal to 1000.

5. The flame retardant polyethylene nonwoven sheet according to claim 1, characterized in that: The composite compatibilizer comprises the following components in parts by weight: 85-87 parts of a second high-density polyethylene resin, 4-6 parts of maleic anhydride, 4-6 parts of glycidyl methacrylate, 2-4 parts of styrene, and 0.5-2 parts of an initiator.

6. The flame-retardant polyethylene nonwoven sheet according to claim 5, characterized in that: The preparation method of the composite compatibilizer comprises the following steps: uniformly mixing a second high-density polyethylene resin, maleic anhydride, glycidyl methacrylate, styrene and an initiator, and performing melt extrusion granulation to obtain the composite compatibilizer.

7. The flame-retardant polyethylene nonwoven sheet according to claim 5, characterized in that: The melt flow rate of the second high-density polyethylene at 190° C. and 2.16 kg load is greater than or equal to 1 g / 10 min and less than or equal to 12 g / 10 min; and / or The initiator includes at least one of azobisisobutyronitrile, potassium persulfate and ammonium persulfate.

8. The flame-retardant polyethylene nonwoven sheet according to claim 1, characterized in that: The weight of the flame retardant polyethylene nonwoven sheet is less than or equal to 110 g / m 2 The limiting oxygen index of the flame-retardant polyethylene nonwoven sheet is greater than or equal to 33%, and the flame retardant protection rate of the flame-retardant polyethylene nonwoven sheet is above 39%.

9. The method for preparing the flame-retardant polyethylene nonwoven sheet according to claims 1 to 8, characterized in that: The following steps are involved: The components are mixed uniformly to obtain a mixture, and the mixture is added into a reaction kettle containing a solvent, and then heated and nitrogen is introduced so that the temperature in the reaction kettle is greater than or equal to 200° C. and less than or equal to 230° C., and the pressure is greater than or equal to 10 MPa and less than or equal to 12 MPa, to obtain a spinning solution; The spinning solution is placed in a flash spinning device for spinning and received by a receiving device. The received product is cold pressed and hot rolled to obtain a flame-retardant polyethylene nonwoven sheet.

10. Use of the flame-retardant polyethylene nonwoven sheet according to any one of claims 1 to 8 in the preparation of home and decoration materials, personal protective equipment, transportation materials, construction and engineering materials, industrial application materials, military and defense materials, electronic and electrical product materials, and fire protection materials.

Images