A fire-retardant multi-layer composite aluminum-plastic panel and its preparation method

Abstract

The present invention discloses a fire-retardant multi-layer composite aluminum-plastic panel and a preparation method thereof. The aluminum-plastic panel comprises the following structure: an aluminum sheet, an adhesive film, and a PE core plate. The upper and lower surfaces of the PE core plate are provided with an adhesive film, and the side of the adhesive film facing away from the PE core plate is provided with an aluminum sheet. The PE core plate comprises the following components by weight: 100 parts of low-density polyethylene, 20 to 25 parts of nylon 6, 10 to 20 parts of flame-retardant modified polyethylene, and 4 to 5 parts of coupled modified magnesium chloride. The present invention synthesizes a flame-retardant skeleton by hexachlorocyclotriphosphazene, 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone, mercaptopropionic acid, and piperazine, and introduces the skeleton into a dibutyl maleate-modified polyethylene structure. The skeleton is co-extruded with low-density polyethylene, nylon 6, and coupled modified calcium carbonate, so that the prepared PE core material has excellent mechanical properties and good flame retardant properties. The adhesive film, aluminum sheet, and PE core plate are composited to achieve the fire-retardant capability of the prepared aluminum-plastic panel.

Description

Technical Field

[0001] The present invention relates to the technical field, in particular to a fire-proof and flame-retardant multi-layer composite aluminum-plastic panel and a preparation method thereof. Background Art

[0002] Aluminum-plastic panels are a widely used decorative material, popular for their affordability, diverse colors, ease of construction, and excellent processing properties. They can be used in a variety of applications, including building exteriors, curtain wall panels, interior decoration, advertising signs, and display stands. Aluminum-plastic panels are made from a composite of multiple layers of materials, generally consisting of an organic core panel and aluminum sheets on the surface of the core panel, which are bonded together with a bonding resin. Polyethylene is often used for organic core panels, but polyethylene has poor heat resistance, which is detrimental to the fire-retardant performance of the resulting aluminum-plastic panel. Therefore, we propose a fire-retardant, multi-layer composite aluminum-plastic panel and a method for its preparation. Summary of the Invention

[0003] The object of the present invention is to provide a fire-resistant and flame-retardant multi-layer composite aluminum-plastic panel and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a fire-retardant multi-layer composite aluminum-plastic panel, the aluminum-plastic panel comprising the following structure: an aluminum sheet, an adhesive film and a PE core board, the upper and lower surfaces of the PE core board are provided with an adhesive film, and the side of the adhesive film facing away from the PE core board is provided with an aluminum sheet.

[0005] Furthermore, the PE core board includes the following components by weight: 100 parts of low-density polyethylene, 20 to 25 parts of nylon 6, 10 to 20 parts of flame-retardant modified polyethylene, and 4 to 5 parts of coupled modified magnesium chloride.

[0006] Furthermore, the flame retardant modified polyethylene includes the following components by weight: 100 parts of dibutyl maleate modified polyethylene and 10 to 30 parts of a flame retardant skeleton.

[0007] Furthermore, the flame retardant skeleton is made from the following components: hexachlorocyclotriphosphazene, 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone, mercaptopropionic acid, and piperazine.

[0008] Furthermore, the film includes the following components by weight: 10 to 15 parts of linear low-density polyethylene, 18 to 21 parts of low-density polyethylene, 23 to 27 parts of dibutyl maleate-modified polyethylene, 23 to 27 parts of ethylene-vinyl acetate copolyester, 4.5 to 5.6 parts of polyolefin elastomer, and 10 to 14 parts of impact-resistant polystyrene.

[0009] Furthermore, the aluminum plate is an aluminum-magnesium alloy; it includes the following weight components: Si: ≤0.30%, Cu: ≤0.20%, Mg: 0.5~1.1%, Zn: ≤0.20%, Mn: ≤0.20%, Cr: ≤0.10%, Fe: ≤0.7, and the balance is Al.

[0010] Furthermore, the thickness of the adhesive film is 0.045-0.055 mm; the thickness of the aluminum plate is 0.20-0.50 mm; and the thickness of the aluminum-plastic plate is 4.0-8.0 mm.

[0011] A method for preparing a fire-retardant multi-layer composite aluminum-plastic panel, comprising the following preparation processes:

[0012] Take two aluminum plates, lay a film on each surface, place the PE core board between the two films, and overlap them;

[0013] The plane is continuously heated and compounded, and the temperature of the heating end is: 120-130°C in the first heating zone, 140-150°C in the second heating zone, and 140-150°C in the third heating zone.

[0014] Furthermore, the PE core board is made by the following process:

[0015] (1) Preparation of flame retardant skeleton:

[0016] Hexachlorocyclotriphosphazene and acetonitrile are mixed, triethylamine is added, and ultrasonic dissolution is carried out at a temperature of 60 to 70°C; 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone is added, the mixture is sealed, and ultrasonic reaction is carried out at a temperature of 60 to 70°C for 5 hours; centrifugation is carried out, and the mixture is washed with deionized water and acetonitrile, and dried at 38 to 45°C for 24 to 36 hours to obtain a phosphorus-containing derivative;

[0017] Take mercaptopropionic acid and piperazine and mix them, raise the temperature to 70-80°C and react for 24 hours; remove water by distillation under reduced pressure to obtain a nitrogen-containing monomer;

[0018] A nitrogen-containing monomer, a phosphorus-containing derivative, and dimethyl sulfoxide are mixed and reacted at a temperature of 25 to 35° C. for 24 hours; washed, dried, and subjected to reduced pressure distillation to obtain a flame-retardant skeleton;

[0019] (2) Preparation of PE core board:

[0020] The dibutyl maleate modified polyethylene and the flame retardant skeleton are mixed, and the mixture is extruded and pelletized through a twin-screw extruder at an extrusion temperature of 140-190°C, a die head temperature of 160°C, and a screw speed of 50-60 r / min to obtain flame retardant modified polyethylene.

[0021] Low-density polyethylene, nylon 6, flame-retardant modified polyethylene, and coupled modified calcium chloride are mixed and extruded through a twin-screw extruder at a temperature of 210-220°C and a screw speed of 40-45 r / min.

[0022] The PE core board is obtained by refining at a temperature of 88 to 92° C. for 5 to 15 minutes, packing 8 to 10 times, and pressing the sheet at a temperature of 172 to 180° C.

[0023] Furthermore, the mass ratio of the hexachlorocyclotriphosphazene to 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone is 0.8:(1.79-1.84);

[0024] The mass ratio of hexachlorocyclotriphosphazene, acetonitrile and triethylamine is (0.37-0.45):100:(1.8-2.1);

[0025] Ultrasonic conditions were 160 W, 59 kHz.

[0026] Furthermore, the mass ratio of mercaptopropionic acid to piperazine is (2.47-2.59):1.

[0027] Furthermore, the mass ratio of the nitrogen-containing monomer, the phosphorus-containing derivative, and dimethyl sulfoxide is (9.7-10.6):18:(180-240).

[0028] Furthermore, dibutyl maleate modified polyethylene is prepared by the following process:

[0029] Take dibutyl maleate, dicumyl peroxide, and acetone, stir and mix to obtain a mixed solution; mix it with low-density polyethylene at high speed and leave it open to allow the acetone to evaporate;

[0030] The dibutyl maleate-modified polyethylene was obtained by reaction extrusion through a twin-screw extruder at an extrusion temperature of 120-180°C, a die head temperature of 160°C, and a screw speed of 45 r / min.

[0031] Furthermore, the mass ratio of dibutyl maleate, dicumyl peroxide, and low-density polyethylene is 1.8:0.14:100; the mass ratio of dibutyl maleate and acetone is 20:100;

[0032] Furthermore, the coupled modified calcium chloride is prepared by the following process:

[0033] Calcium carbonate was dried, and 3-mercaptopropyltrimethoxysilane was added thereto. The mixture was stirred at 75° C. at a speed of 300 r / min for 1 h. The mass ratio of 3-mercaptopropyltrimethoxysilane to calcium carbonate was 1:100.

[0034] In the above technical solution, the phosphorus chloride in hexachlorocyclotriphosphazene reacts and crosslinks with the phenol in 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone to obtain a three-dimensional network macromolecular chain having a phosphazene and benzene ring structure, forming a large sterically hindered phosphorus-containing derivative; the carboxyl group in mercaptopropionic acid reacts with the amino group in piperazine to obtain a nitrogen-containing monomer having a dithiol group; the nitrogen-containing monomer is mixed with the phosphorus-containing derivative, and the thiol group therein reacts with double bonds and hydroxyl groups to obtain a flame-retardant skeleton containing nitrogen and phosphorus elements. The phosphoric acid and phosphorous acid produced by thermal decomposition can promote the carbonization of the benzene ring structure, thereby increasing the initial decomposition temperature and the solid residue rate. The residual carbon has abundant micropores, which reduce the mean free path of small molecules and prevent the escape of small molecules generated by combustion. The free radicals generated by the decomposition of hydroxyl groups in the system can capture free radicals generated by polyethylene, inhibiting the combustion of polyethylene and the generation of smoke, thereby achieving flame retardancy.

[0035] The flame-retardant skeleton is co-extruded with dibutyl maleate-modified polyethylene, so that the flame-retardant skeleton is grafted onto the polyethylene molecular chain to obtain flame-retardant modified polyethylene; the flame-retardant skeleton has a high surface energy and has good compatibility with low-density polyethylene, nylon 6, and coupled modified calcium chloride. It cooperates with the coupled modified calcium chloride to produce a certain cross-linking and bonding effect, thereby improving the mechanical properties and heat resistance of the prepared PE core board, and effectively improving the fire retardant ability of the prepared PE core board; and the amide groups in nylon 6 are complexed with calcium ions in calcium chloride, destroying the hydrogen bonding effect of the nylon 6 molecular chain, hindering the movement of the nylon 6 molecular chain, and further improving the mechanical properties of the prepared PE core board.

[0036] Furthermore, the adhesive film is prepared by the following process:

[0037] Take linear low-density polyethylene, dibutyl maleate-modified polyethylene, ethylene-vinyl acetate copolyester, low-density polyethylene, polyolefin elastomer, and impact polystyrene and mix them for 20 to 30 minutes;

[0038] The film is formed by twin-screw extrusion and stretching, with an extrusion temperature of 150 to 230° C. and a screw speed of 250 to 450 rpm.

[0039] In the above technical solution, impact-resistant polystyrene is added to the film component system. It has butyl rubber and benzene ring structure and has good compatibility with polyethylene. At the same time, it can improve the separation of polarity and non-polarity in the system, promote the movement of dibutyl maleate to the interface between the film and the aluminum plate, facilitate the bonding between the aluminum plate and the PE core plate, and improve the bonding strength and stability.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The invention discloses a fireproof and flame-retardant multi-layer composite aluminum-plastic panel and a preparation method thereof. The flame-retardant skeleton is synthesized by using hexachlorocyclotriphosphazene, 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone, mercaptopropionic acid and piperazine, and the synthesized flame-retardant skeleton is introduced into a dibutyl maleate-modified polyethylene structure. The skeleton is then co-extruded with low-density polyethylene, nylon 6 and coupled modified calcium carbonate, so that the prepared PE core material has excellent mechanical properties and good flame-retardant properties. The fireproof and flame-retardant capabilities of the prepared aluminum-plastic panel are achieved by compounding an adhesive film, an aluminum plate and the PE core plate. DETAILED DESCRIPTION

[0042] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0043] Example 1

[0044] (1) Preparation of PE core board:

[0045] 1.1. Mix hexachlorocyclotriphosphazene and acetonitrile, add triethylamine, and sonicate at 60°C to dissolve. Add 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone, seal, and sonicate at 60°C for 5 h. Centrifuge, wash with deionized water and acetonitrile, and dry at 38°C for 24 h to obtain a phosphorus-containing derivative.

[0046] The mass ratio of hexachlorocyclotriphosphazene to 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone was 0.8:1.79; the mass ratio of hexachlorocyclotriphosphazene to acetonitrile to triethylamine was 0.37:100:1.8; and the ultrasonic conditions were 160W, 59kHz.

[0047] Take mercaptopropionic acid and piperazine and mix them, heat them to 70°C and react for 24 hours; remove water by distillation under reduced pressure to obtain a nitrogen-containing monomer; the mass ratio of mercaptopropionic acid to piperazine is 2.47:1;

[0048] A nitrogen-containing monomer, a phosphorus-containing derivative, and dimethyl sulfoxide were mixed and reacted at 25°C for 24 hours; washed, dried, and distilled under reduced pressure to obtain a flame retardant skeleton; the mass ratio of the nitrogen-containing monomer, the phosphorus-containing derivative, and the dimethyl sulfoxide was 9.7:18:180;

[0049] 1.2. Take dibutyl maleate modified polyethylene and flame retardant skeleton mixed, through the twin-screw extruder reaction extrusion, pelletization, extrusion temperature of 140 ~ 190 ℃, head temperature of 160 ℃, screw speed of 50 r / min, to obtain flame retardant modified polyethylene; flame retardant modified polyethylene comprises the following components by weight: 100 parts of dibutyl maleate modified polyethylene, 10 parts of flame retardant skeleton;

[0050] Low-density polyethylene, nylon 6, flame-retardant modified polyethylene, and coupled modified calcium chloride were mixed and extruded through a twin-screw extruder at a temperature of 210-220°C and a screw speed of 40 r / min.

[0051] The PE core board includes the following components by weight: 100 parts of low-density polyethylene, 20 parts of nylon 6, 10 parts of flame-retardant modified polyethylene, and 4 parts of coupled modified magnesium chloride;

[0052] The PE core board was obtained by refining at 88°C for 5 minutes, packing 8 times, and pressing at 172°C.

[0053] (2) Preparation of film:

[0054] Take linear low-density polyethylene, dibutyl maleate-modified polyethylene, ethylene-vinyl acetate copolyester, low-density polyethylene, polyolefin elastomer, and impact polystyrene and mix them for 20 minutes;

[0055] The film is formed by twin-screw extrusion at a temperature of 150-230°C and a screw speed of 250 rpm.

[0056] The film comprises the following components by weight: 10 parts of linear low-density polyethylene, 18 parts of low-density polyethylene, 23 parts of dibutyl maleate-modified polyethylene, 23 parts of ethylene-vinyl acetate copolyester, 4.5 parts of polyolefin elastomer, and 10 parts of impact-resistant polystyrene;

[0057] (3) Preparation of aluminum-plastic panels:

[0058] Take two aluminum plates, lay a film on each surface, place the PE core board between the two films, and overlap them;

[0059] Perform continuous heating and lamination on the plane, with the heating end temperatures being: 120°C in the first heating zone, 140°C in the second heating zone, and 140°C in the third heating zone;

[0060] The thickness of the film is 0.05mm; the thickness of the aluminum plate is 0.20mm; the thickness of the aluminum-plastic plate is 6mm.

[0061] Example 2

[0062] (1) Preparation of PE core board:

[0063] 1.1. Mix hexachlorocyclotriphosphazene and acetonitrile, add triethylamine, and dissolve by ultrasonication at 65°C. Add 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone, seal, and ultrasonicate at 65°C for 5 h. Centrifuge, wash with deionized water and acetonitrile, and dry at 40°C for 30 h to obtain a phosphorus-containing derivative.

[0064] The mass ratio of hexachlorocyclotriphosphazene to 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone was 0.8:1.81; the mass ratio of hexachlorocyclotriphosphazene to acetonitrile to triethylamine was 0.41:100:2.0; and the ultrasonic conditions were 160W, 59kHz.

[0065] Mercaptopropionic acid and piperazine were mixed and heated to 75°C for 24 hours. Water was removed by distillation under reduced pressure to obtain a nitrogen-containing monomer. The mass ratio of mercaptopropionic acid to piperazine was 2.55:1. The mass ratio of nitrogen-containing monomer, phosphorus-containing derivative, and dimethyl sulfoxide was 10.2:18:210.

[0066] A nitrogen-containing monomer, a phosphorus-containing derivative, and dimethyl sulfoxide are mixed and reacted at 30°C for 24 hours; washed, dried, and subjected to reduced pressure distillation to obtain a flame-retardant skeleton;

[0067] 1.2. Take dibutyl maleate modified polyethylene and flame retardant skeleton mixed, through the twin-screw extruder reaction extrusion, pelletization, extrusion temperature of 140 ~ 190 ℃, head temperature of 160 ℃, screw speed of 55 r / min, to obtain flame retardant modified polyethylene; flame retardant modified polyethylene comprises the following components by weight: 100 parts of dibutyl maleate modified polyethylene, 20 parts of flame retardant skeleton;

[0068] Low-density polyethylene, nylon 6, flame-retardant modified polyethylene, and coupled modified calcium chloride were mixed and extruded through a twin-screw extruder at a temperature of 210-220°C and a screw speed of 45 r / min.

[0069] The PE core board includes the following components by weight: 100 parts of low-density polyethylene, 22 parts of nylon 6, 15 parts of flame-retardant modified polyethylene, and 4.5 parts of coupled modified magnesium chloride;

[0070] The PE core board was obtained by refining at 90°C for 10 minutes, packing 9 times, and pressing at 176°C.

[0071] (2) Preparation of film:

[0072] Take linear low-density polyethylene, dibutyl maleate-modified polyethylene, ethylene-vinyl acetate copolyester, low-density polyethylene, polyolefin elastomer, and high-impact polystyrene and mix them for 25 minutes;

[0073] The film is formed by twin-screw extrusion and stretching, with an extrusion temperature of 150-230°C and a screw speed of 350 rpm;

[0074] The film comprises the following components by weight: 12 parts of linear low-density polyethylene, 20 parts of low-density polyethylene, 25 parts of dibutyl maleate-modified polyethylene, 25 parts of ethylene-vinyl acetate copolyester, 5 parts of polyolefin elastomer, and 12 parts of impact-resistant polystyrene;

[0075] (3) Preparation of aluminum-plastic panels:

[0076] Take two aluminum plates, lay a film on each surface, place the PE core board between the two films, and overlap them;

[0077] Perform continuous heating and lamination on the plane, with the heating end temperatures being: 125°C in the first heating zone, 145°C in the second heating zone, and 145°C in the third heating zone;

[0078] The thickness of the film is 0.05mm; the thickness of the aluminum plate is 0.20mm; the thickness of the aluminum-plastic plate is 6mm.

[0079] Example 3

[0080] (1) Preparation of PE core board:

[0081] 1.1. Mix hexachlorocyclotriphosphazene and acetonitrile, add triethylamine, and sonicate at 70°C to dissolve. Add 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone, seal, and sonicate at 70°C for 5 h. Centrifuge, wash with deionized water and acetonitrile, and dry at 45°C for 36 h to obtain a phosphorus-containing derivative.

[0082] The mass ratio of hexachlorocyclotriphosphazene to 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone was 0.8:1.84; the mass ratio of hexachlorocyclotriphosphazene to acetonitrile to triethylamine was 0.45:100:2.1; and the ultrasonic conditions were 160W, 59kHz.

[0083] Mercaptopropionic acid and piperazine were mixed and heated to 80°C for 24 hours. Water was removed by distillation under reduced pressure to obtain a nitrogen-containing monomer. The mass ratio of mercaptopropionic acid to piperazine was 2.59:1. The mass ratio of nitrogen-containing monomer, phosphorus-containing derivative, and dimethyl sulfoxide was 10.6:18:240.

[0084] A nitrogen-containing monomer, a phosphorus-containing derivative, and dimethyl sulfoxide are mixed and reacted at 35°C for 24 hours; washed, dried, and subjected to reduced pressure distillation to obtain a flame-retardant skeleton;

[0085] 1.2. Take dibutyl maleate modified polyethylene and flame retardant skeleton mixed, through the twin-screw extruder reaction extrusion, pelletization, extrusion temperature of 140 ~ 190 ℃, head temperature of 160 ℃, screw speed of 60 r / min, to obtain flame retardant modified polyethylene; flame retardant modified polyethylene comprises the following components by weight: 100 parts of dibutyl maleate modified polyethylene, 30 parts of flame retardant skeleton;

[0086] Low-density polyethylene, nylon 6, flame-retardant modified polyethylene, and coupled modified calcium chloride were mixed and extruded through a twin-screw extruder at a temperature of 210-220°C and a screw speed of 45 r / min.

[0087] The PE core board includes the following components by weight: 100 parts of low-density polyethylene, 25 parts of nylon 6, 20 parts of flame-retardant modified polyethylene, and 5 parts of coupled modified magnesium chloride;

[0088] The PE core board was obtained by refining at 92°C for 15 minutes, packing 10 times, and pressing at 180°C.

[0089] (2) Preparation of film:

[0090] Take linear low-density polyethylene, dibutyl maleate-modified polyethylene, ethylene-vinyl acetate copolyester, low-density polyethylene, polyolefin elastomer, and high-impact polystyrene and mix them for 30 minutes;

[0091] The film is formed by twin-screw extrusion and stretching, with an extrusion temperature of 150-230°C and a screw speed of 450 rpm;

[0092] The film comprises the following components by weight: 15 parts of linear low-density polyethylene, 21 parts of low-density polyethylene, 27 parts of dibutyl maleate-modified polyethylene, 27 parts of ethylene-vinyl acetate copolyester, 5.6 parts of polyolefin elastomer, and 14 parts of high-impact polystyrene;

[0093] (3) Preparation of aluminum-plastic panels:

[0094] Take two aluminum plates, lay a film on each surface, place the PE core board between the two films, and overlap them;

[0095] Perform continuous heating and lamination on the plane, with the heating end temperatures being: 130°C in the first heating zone, 150°C in the second heating zone, and 150°C in the third heating zone;

[0096] The thickness of the film is 0.05mm; the thickness of the aluminum plate is 0.20mm; the thickness of the aluminum-plastic plate is 6mm.

[0097] Comparative Example 1

[0098] The nitrogen-containing monomer in process (1) is replaced with hexanedithiol to prepare a PE core board;

[0099] Processes (2) and (3) are the same as in Example 1 to obtain an aluminum-plastic panel.

[0100] Comparative Example 2

[0101] The nitrogen-containing monomer in process (1) is replaced by hexamethylenedithiol, and the phosphorus-containing derivative is replaced by 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone to prepare a PE core board;

[0102] Processes (2) and (3) are the same as in Example 1 to obtain an aluminum-plastic panel.

[0103] Comparative Example 3

[0104] Low-density polyethylene, nylon 6, flame-retardant skeleton, dibutyl maleate-modified polyethylene, and coupled modified calcium chloride are mixed and extruded through a twin-screw extruder at a temperature of 210-220°C and a screw speed of 40 r / min. The mixture is then refining at 88°C for 5 minutes, baling the mixture 8 times, and sheeting is performed at 172°C to obtain a PE core board.

[0105] The PE core board includes the following components by weight: 100 parts of low-density polyethylene, 20 parts of nylon 6, 1 part of flame-retardant skeleton, 9 parts of dibutyl maleate modified polyethylene, and 4 parts of coupled modified magnesium chloride;

[0106] Processes 1.1, (2) and (3) are the same as those in Example 1 to obtain an aluminum-plastic panel.

[0107] Comparative Example 4

[0108] Low-density polyethylene, nylon 6, flame-retardant skeleton, dibutyl maleate-modified polyethylene, and coupled modified calcium chloride are mixed and extruded through a twin-screw extruder at a temperature of 210-220°C and a screw speed of 40 r / min. The mixture is then refining at 88°C for 5 minutes, baling the mixture 8 times, and sheeting is performed at 172°C to obtain a PE core board.

[0109] The PE core board includes the following components by weight: 100 parts of low-density polyethylene, 20 parts of nylon 6, 1 part of flame-retardant skeleton, 9 parts of dibutyl maleate modified polyethylene, and 4 parts of coupled modified magnesium chloride;

[0110] Processes 1.1, (2) and (3) are the same as those in Comparative Example 2 to obtain an aluminum-plastic panel.

[0111] Comparative Example 5

[0112] Low-density polyethylene, nylon 6, maleic anhydride-modified polyethylene, and coupled modified calcium chloride are mixed and extruded through a twin-screw extruder at a temperature of 210-220°C and a screw speed of 40 r / min. The mixture is then refining at 88°C for 5 minutes, baling the mixture 8 times, and sheeting is performed at 172°C to obtain a PE core board.

[0113] The PE core board includes the following components by weight: 100 parts of low-density polyethylene, 20 parts of nylon 6, 10 parts of maleic anhydride-modified polyethylene, and 4 parts of coupled modified magnesium chloride;

[0114] Processes (2) and (3) are the same as in Example 1 to obtain an aluminum-plastic panel.

[0115] Comparative Example 6

[0116] (2) Preparation of film:

[0117] Take linear low-density polyethylene, maleic anhydride-modified polyethylene, ethylene-vinyl acetate copolyester, low-density polyethylene, and polyolefin elastomer and mix them for 25 minutes;

[0118] The film is formed by twin-screw extrusion and stretching, with an extrusion temperature of 150-230°C and a screw speed of 350 rpm;

[0119] The film comprises the following components by weight: 20 parts of linear low-density polyethylene, 24 parts of low-density polyethylene, 25 parts of maleic anhydride-modified polyethylene, 25 parts of ethylene-vinyl acetate copolyester, and 5 parts of polyolefin elastomer;

[0120] Processes (1) and (3) are the same as those in Comparative Example 5 to obtain an aluminum-plastic panel.

[0121] The above-mentioned low-density polyethylene: 1C7A, purchased from Sinopec Beijing Yanshan Petrochemical Co., Ltd., melt index 6.91g / 10min;

[0122] Nylon 6: M2800, purchased from Nanjing Xinhui Meida Chemical Plastic Co., Ltd., with a melt index of 15.7 g / 10 min;

[0123] Calcium carbonate: ZS-1, purchased from Zibo Zengsheng Chemical Co., Ltd.;

[0124] Linear low-density polyethylene: 7042, purchased from Ningxia Baofeng Energy Group Co., Ltd., melt index 1.89 g / 10 min;

[0125] Ethylene-vinyl acetate copolyester: 14-2, purchased from Beijing Dongfang Petrochemical Co., Ltd., melt index 2.03 g / 10 min;

[0126] Polyolefin elastomer: 0201, purchased from ExxonMobil, melt index 2.5 g / 10 min;

[0127] Impact polystyrene: 825, purchased from PetroChina Dushanzi Petrochemical Company, melt index 2.5 g / 10 min.

[0128] The aluminum plate is an aluminum-magnesium alloy; it includes the following weight components: Si: 0.24%, Cu: 0.09%, Mg: 0.87%, Zn: 0.12%, Mn: 0.12%, Cr: 0.06%, Fe: 0.11, and the balance is Al.

[0129] The above-mentioned dibutyl maleate modified polyethylene is prepared by the following process:

[0130] Take dibutyl maleate, dicumyl peroxide, and acetone, stir and mix to obtain a mixed solution; mix it with low-density polyethylene at high speed and leave it open to allow the acetone to evaporate;

[0131] The dibutyl maleate-modified polyethylene was obtained by reaction extrusion through a twin-screw extruder at an extrusion temperature of 120-180°C, a die head temperature of 160°C, and a screw speed of 45 r / min.

[0132] The mass ratio of dibutyl maleate, dicumyl peroxide, and low-density polyethylene is 1.8:0.14:100; the mass ratio of dibutyl maleate and acetone is 20:100;

[0133] The above-mentioned coupled modified calcium chloride is prepared by the following process:

[0134] Calcium carbonate was dried, and 3-mercaptopropyltrimethoxysilane was added thereto. The mixture was stirred at 75° C. at a speed of 300 r / min for 1 h. The mass ratio of 3-mercaptopropyltrimethoxysilane to calcium carbonate was 1:100.

[0135] experiment

[0136] The aluminum-plastic panels obtained in Examples 1-3 and Comparative Examples 1-6 were taken to prepare samples, and their properties were tested and the test results were recorded:

[0137] Tensile properties: GB / T 1040-2006 was used as the reference standard. The tensile test was carried out using an electronic universal testing machine. The specimen was dumbbell-shaped, the test gauge length was 25 mm, and the tensile speed was 50 mm / min.

[0138] Flame retardant properties: GB / T 2406-1993 was used as the reference standard to test the limiting oxygen index (LOI) of the sample. The sample size was 150 mm × 10 mm × 3 mm.

[0139] Fire rating: Based on GB / T 8625-2005 as the reference standard, the smoke density level of the sample is tested to determine the fire rating of the sample.

[0140] Table 1:

[0141] PE core board Tensile strength (MPa) Elongation at break (%) Limiting oxygen index Example 1 17.43 82.42 32.4 Example 2 18.26 70.13 33.8 Example 3 19.64 56.63 35.3 Comparative Example 1 16.74 84.59 29.5 Comparative Example 2 16.42 87.52 28.6 Comparative Example 3 16.38 89.72 26.7 Comparative Example 4 15.96 91.32 25.5 Comparative Example 5 15.78 92.62 23.9

[0142] Table 2:

[0143] Aluminum-plastic panels 180° peel strength (N / mm) Fire rating Example 1 7.8 Level A2 Example 2 8.3 Level A2 Example 3 9.0 Level A1 Comparative Example 1 / Level A2 Comparative Example 2 / Level B1 Comparative Example 3 / Level B1 Comparative Example 4 / Level B1 Comparative Example 5 / Level B1 Comparative Example 6 6.3 Level B1

[0144] According to the data in the above table, we can clearly draw the following conclusions:

[0145] The aluminum-plastic panels obtained in Examples 1-3 were compared with those obtained in Comparative Examples 1-6. The test results show that:

[0146] Compared with Comparative Example 6, the PE core board obtained in Example 1-3 has more excellent tensile strength and limiting oxygen index data, and the aluminum-plastic panel has a better fire rating; this fully demonstrates that the present invention achieves improvements in the mechanical properties and flame retardant properties of the prepared PE core board and the fire retardant properties of the aluminum-plastic panel;

[0147] Compared with Example 1, the tensile strength and limiting oxygen index data of the PE core boards obtained in Comparative Examples 1-5 deteriorated, and the fire resistance level of the aluminum-plastic board decreased; the peel strength data between the film and the aluminum plate in Comparative Example 6 was even lower; it can be seen that the present invention's setting of the PE core board process and the components used can promote the improvement of the mechanical properties, flame retardant properties of the PE core board and the fire retardant properties of the aluminum-plastic board; the setting of the film process and the components used can improve the bonding strength between the film and the aluminum plate.

[0148] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include," "comprise," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0149] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A fire-retardant multi-layer composite aluminum-plastic panel, characterized by: The aluminum-plastic panel comprises the following structure: An aluminum plate, an adhesive film, and a PE core plate, wherein the upper and lower surfaces of the PE core plate are provided with adhesive films, and an aluminum plate is provided on the side of the adhesive film facing away from the PE core plate; The PE core board comprises the following components by weight: 100 parts of low-density polyethylene, 20-25 parts of nylon 6, 10-20 parts of flame-retardant modified polyethylene, and 4-5 parts of coupled modified magnesium chloride; The flame retardant modified polyethylene comprises the following components by weight: 100 parts of dibutyl maleate modified polyethylene, 10 to 30 parts of flame retardant skeleton; The flame retardant skeleton is prepared from the following components: hexachlorocyclotriphosphazene, 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone, mercaptopropionic acid, and piperazine; The flame retardant skeleton is prepared by the following process: Mix hexachlorocyclotriphosphazene and acetonitrile, add triethylamine, and dissolve by ultrasonication at 60-70°C; add 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone, seal, and react by ultrasonication at 60-70°C for 5 hours; The mixture was centrifuged, washed with deionized water and acetonitrile, and dried at 38-45°C for 24-36 hours to obtain a phosphorus-containing derivative; Take mercaptopropionic acid and piperazine and mix them, raise the temperature to 70-80°C and react for 24 hours; remove water by distillation under reduced pressure to obtain a nitrogen-containing monomer; A nitrogen-containing monomer, a phosphorus-containing derivative and dimethyl sulfoxide are mixed and reacted at a temperature of 25-35° C. for 24 hours; washed, dried and subjected to reduced pressure distillation to obtain a flame retardant skeleton.

2. The fire-retardant multi-layer composite aluminum-plastic panel according to claim 1, characterized in that: The adhesive film comprises the following components by weight: 10 to 15 parts of linear low-density polyethylene, 18 to 21 parts of low-density polyethylene, 23 to 27 parts of dibutyl maleate-modified polyethylene, 23 to 27 parts of ethylene-vinyl acetate copolyester, 4.5 to 5.6 parts of polyolefin elastomer, and 10 to 14 parts of impact-resistant polystyrene.

3. The fire-retardant multi-layer composite aluminum-plastic panel according to claim 1, characterized in that: The aluminum plate is an aluminum-magnesium alloy.

4. The fire-retardant multi-layer composite aluminum-plastic panel according to claim 1, characterized in that: The thickness of the adhesive film is 0.045-0.055 mm; the thickness of the aluminum plate is 0.20-0.50 mm; and the thickness of the aluminum-plastic plate is 4.0-8.0 mm.

5. The method for preparing a fire-retardant multi-layer composite aluminum-plastic panel according to any one of claims 1 to 4, characterized in that: The preparation process includes the following: Take two aluminum plates, lay a film on each surface, place the PE core board between the two films, and overlap them; Carry out plane continuous heating and compounding, the temperature of the heating end is: 120-130℃ in the first heating zone, 140-150℃ in the second heating zone, and 140-150℃ in the third heating zone; The PE core board is made by the following process: The dibutyl maleate modified polyethylene and the flame retardant skeleton are mixed, and the mixture is extruded and pelletized through a twin-screw extruder at an extrusion temperature of 140-190°C, a die head temperature of 160°C, and a screw speed of 50-60 r / min to obtain flame retardant modified polyethylene. Low-density polyethylene, nylon 6, flame-retardant modified polyethylene, and coupled modified calcium chloride are mixed and extruded through a twin-screw extruder at a temperature of 210-220°C and a screw speed of 40-45 r / min. The PE core board is obtained by refining at a temperature of 88 to 92° C. for 5 to 15 minutes, packing 8 to 10 times, and pressing the sheet at a temperature of 172 to 180° C.

6. The method for preparing a fire-retardant multi-layer composite aluminum-plastic panel according to claim 5, characterized in that: The mass ratio of the hexachlorocyclotriphosphazene to 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone is 0.8:(1.79-1.84); The mass ratio of the mercaptopropionic acid to piperazine is (2.47-2.59):

1.

7. The method for preparing a fire-retardant multi-layer composite aluminum-plastic panel according to claim 5, characterized in that: The film is prepared by the following process: Take linear low-density polyethylene, dibutyl maleate-modified polyethylene, ethylene-vinyl acetate copolyester, low-density polyethylene, polyolefin elastomer, and impact polystyrene and mix them for 20 to 30 minutes; The film is formed by twin-screw extrusion and stretching, with an extrusion temperature of 150 to 230° C. and a screw speed of 250 to 450 rpm.