A waterproof and flame-retardant high-performance composite corrugated paper and preparation method thereof

Abstract

The present invention discloses a waterproof, flame-retardant, high-performance composite corrugated paper and a preparation method thereof, comprising an outer waterproof, antistatic composite reinforced coating, a face paper layer, a corrugated paper core layer, a back paper layer, and an inner waterproof, antistatic reinforced composite coating, which are sequentially arranged from the outside to the inside. The waterproof, flame-retardant, high-performance composite corrugated paper of the present invention can impart excellent waterproof and antistatic properties to the surface by coating the face paper layer and the back paper layer with a waterproof, antistatic composite reinforced coating, and can also improve the flame retardant ability; further, the face paper layer, the corrugated paper core layer, and the back paper layer are bonded with a self-made flame retardant adhesive, which can further improve the flame retardant performance and improve the overall strength.

Description

Technical Field

[0001] The invention relates to the field of corrugated paper, and in particular to a waterproof and flame-retardant high-performance composite corrugated paper and a preparation method thereof. Background Art

[0002] Corrugated paperboard is a paper composite board with high mechanical strength and is widely used in the packaging field. However, the current corrugated paper has the following shortcomings in the application process:

[0003] 1. Corrugated paper is easy to burn when exposed to open flames, which poses a great safety hazard. In order to solve this problem, it is generally necessary to modify the corrugated paperboard to be flame retardant. The traditional method is mainly to add flame retardants to the inside of the corrugated paperboard or attach them to its surface by adding them to the pulp, impregnating the finished product or coating the surface to provide flame retardant properties. The flame retardant added to the pulp is easy to lose or migrate in the corrugated paper system, and will affect the processing and forming properties of the paper. On the other hand, the flame retardant migrates to the surface or reacts with other components in the corrugated paper system. It is also easy to gradually deactivate, and the flame retardant performance decreases and it is impossible to maintain long-term flame retardancy. The method of impregnation or surface coating of the finished product will affect the flatness and stiffness of the corrugated paper, and the flame retardant component only exists on the surface, and the overall flame retardant effect is not ideal.

[0004] 2. The trace amount of static electricity hidden in the packaging material will affect electronic components, integrated circuits and other precision electronic products and cause product defects. Therefore, for items that are easily damaged in static fields, the packaging cartons used must have certain antistatic properties to prevent static charges from accumulating on the surface of the cartons. However, traditional corrugated paper usually does not have surface antistatic properties.

[0005] 3. Traditional corrugated paper has poor waterproof properties and is easy to absorb moisture. Its performance will be greatly reduced, and it may even become unusable.

[0006] Some solutions are provided in the prior art to try to solve the above problems.

[0007] Patent CN116397461B_A waterproof and flame-retardant composite corrugated paperboard and its composite process, which effectively increases the compression, folding and impact resistance of the paperboard through glass fiber composite, increases the amount of flame retardant under the premise of ensuring the performance of corrugated paper, and improves the flame retardant effect. The adhesive used in the present invention is green and environmentally friendly, has good durability, and has flame retardant and waterproof functions at the same time, which effectively improves the durability of corrugated paper. However, this solution still cannot effectively inhibit the loss or migration of flame retardants in the system, and cannot provide long-term flame retardant performance; in addition, it cannot improve the excellent surface antistatic performance.

[0008] Patent CN117966517B discloses a waterproof and flame-retardant corrugated paper and its preparation method, which comprises compounding oxidized starch adhesive, magnesium hydroxide or aluminum hydroxide synergistic flame retardant, and starch-ammonium polyphosphate microcapsule flame retardant to obtain a flame retardant solution, and then coating the surface of the corrugated paper. The starch-ammonium polyphosphate microcapsule flame retardant uses starch as a carbon source, ammonium polyphosphate as an acid source, and triazine groups as a vapor source to form an expansion flame retardant system. The biphenyl hydrophobic group contained in the starch-ammonium polyphosphate microcapsule flame retardant can enhance the hydrophobicity of the flame retardant solution film to a certain extent, and can form a hydrophobic film on the surface of the corrugated paper, which is beneficial to improve the water resistance and waterproof performance of the corrugated paper. However, this scheme adopts the surface coating method to introduce the flame retardant, and there is no flame retardant component inside, which has limited improvement on the flame retardant performance; in addition, it also does not effectively improve the antistatic performance of the corrugated paper.

[0009] Therefore, it is necessary to improve the existing technology to provide a more reliable solution. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide a waterproof and flame-retardant high-performance composite corrugated paper and a preparation method thereof in view of the deficiencies in the above-mentioned prior art.

[0011] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: In the first aspect of the present invention, a waterproof and flame-retardant high-performance composite corrugated paper is provided, comprising an outer waterproof and antistatic composite enhanced coating, a surface paper layer, a corrugated paper core layer, a lining paper layer, and an inner waterproof and antistatic enhanced composite coating arranged in sequence from the outside to the inside;

[0012] The outer waterproof antistatic composite enhanced coating and the inner waterproof antistatic enhanced composite coating are both obtained by coating a waterproof antistatic composite enhanced coating and then curing it. The waterproof antistatic composite enhanced coating includes the following raw material components in parts by weight:

[0013] 55-75 parts of bisphenol A epoxy resin, 10-24 parts of methyl silicone resin, 2-6.5 parts of tetraethylene pentamine, 3-12 parts of chlorinated paraffin, 3-18 parts of composite multi-effect enhancer, and 40-70 parts of acetone.

[0014] Preferably, the composite multi-effect enhancer is prepared by the following steps:

[0015] S1, preparing acidified carbon nanotubes;

[0016] S2, preparing porous silica microspheres;

[0017] S3, using acidified carbon nanotubes and porous silica microspheres to prepare aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2;

[0018] S4, loading a flame retardant on MWCNTs@Al2O3@SiO2 to obtain a composite filler loaded with a flame retardant;

[0019] S5. Coating a hydrophobic modified film on the composite filler loaded with a flame retardant to obtain the composite multi-effect enhancer.

[0020] Preferably, step S1 specifically comprises: adding multi-walled carbon nanotubes to a mixed acid solution consisting of 95wt% concentrated sulfuric acid and 65wt% concentrated nitric acid, ultrasonicating, then stirring and refluxing under heating, cooling to room temperature and filtering, washing with deionized water until neutral, and vacuum drying to obtain acidified carbon nanotubes;

[0021] Step S2 is specifically as follows:

[0022] S2-1, adding hexadecyltrimethylammonium bromide and 1,3,5-trimethylbenzene to an alcohol solution consisting of isopropanol and deionized water, ultrasonically dispersing, adding ammonia water, and ultrasonically dispersing;

[0023] S2-2, adding ethyl orthosilicate to the mixture obtained in step S2-1 under stirring, reacting under heating, filtering after the reaction, washing the solid product, and calcining under air atmosphere to obtain porous silica microspheres.

[0024] Preferably, step S3 specifically comprises:

[0025] S3-1, taking porous silica microspheres and adding them into an ethanol aqueous solution composed of deionized water and ethanol, ultrasonically dispersing them, then adding Al(NO3)3·9H2O and stirring to obtain a microsphere dispersion;

[0026] S3-2, adding the acidified carbon nanotubes into deionized water, and dispersing by ultrasonication to obtain a carbon nanotube dispersion;

[0027] S3-3. Add the carbon nanotube dispersion to the microsphere dispersion under stirring, stir, transfer the obtained mixture to a reactor, react under heating, cool to room temperature after the reaction is completed, centrifuge and filter, wash the solid product, and vacuum dry to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2.

[0028] Preferably, step S4 is specifically as follows: adding dimethyl methylphosphonate to deionized water, stirring, adding MWCNTs@Al2O3@SiO2 prepared in step S3 under stirring, ultrasonically dispersing, then naturally cooling to room temperature, standing, centrifugal filtering, washing the solid product with ethanol, and vacuum drying to obtain a composite filler loaded with a flame retardant: DMMP-MWCNTs@Al2O3@SiO2.

[0029] Preferably, step S5 is specifically:

[0030] S5-1, taking the DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, adding it to ethanol, ultrasonically dispersing it, then adding 3-aminopropyltriethoxysilane, reacting under heating, centrifuging the product, adding the solid product to toluene, ultrasonically dispersing it, and obtaining a filler dispersion;

[0031] S5-2. Add styrene, hydroxy silicone oil and azobisisobutyronitrile to the filler dispersion, pass nitrogen under stirring, and heat to react; then add styrene, hydroxy silicone oil and azobisisobutyronitrile, and heat to react. After the reaction is completed, the product is centrifuged, the solid product is washed, and vacuum dried to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

[0032] Preferably, the composite multi-effect enhancer is prepared by the following steps:

[0033] S1. Preparation of acidified carbon nanotubes:

[0034] 2 g of multi-walled carbon nanotubes were added to 200 mL of a mixed acid solution consisting of 95 wt% concentrated sulfuric acid and 65 wt% concentrated nitric acid in a volume ratio of 3:1, ultrasonicated for 2 h, then stirred and refluxed at 80 ° C for 12 h, cooled to room temperature and filtered, washed with deionized water until neutral, and vacuum dried at 90 ° C for 8 h to obtain acidified carbon nanotubes;

[0035] S2. Preparation of porous silica microspheres:

[0036] S2-1, take 2g of hexadecyltrimethylammonium bromide (CTAB) and 0.85g of 1,3,5-trimethylbenzene, add them into 360mL of an alcohol solution composed of isopropanol and deionized water in a volume ratio of 1:1, ultrasonically disperse for 5min, add 5mL of 25% ammonia water, and ultrasonically disperse for 15min;

[0037] S2-2, adding 12.5 mL of tetraethyl orthosilicate to the mixture obtained in step S2-1 under stirring, reacting at 55° C. for 12 h, filtering after the reaction, washing the solid product with ethanol and deionized water in sequence, and calcining at 550° C. in air atmosphere for 5 h to obtain porous silica microspheres;

[0038] S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler:

[0039] S3-1, take 1g of porous silica microspheres and add them into an ethanol aqueous solution consisting of 80mL of deionized water and 120mL of ethanol, ultrasonically disperse for 30min, then add 1.125g of Al(NO3)3·9H2O, stir at 600rpm for 45min to obtain a microsphere dispersion;

[0040] S3-2, taking 0.8 g of acidified carbon nanotubes and adding them into 100 mL of deionized water, and ultrasonically dispersing them for 30 min to obtain a carbon nanotube dispersion;

[0041] S3-3, under stirring, adding the carbon nanotube dispersion to the microsphere dispersion, stirring for 60 minutes, transferring the obtained mixture to a reactor, reacting at 200°C for 12 hours, cooling to room temperature after the reaction, centrifuging and filtering, washing the solid product with deionized water, and vacuum drying at 90°C for 8 hours to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2;

[0042] S4, loaded flame retardant:

[0043] 2 g of dimethyl methylphosphonate was added to 100 mL of deionized water, stirred at 90° C. for 15 min, 1.5 g of MWCNTs@Al2O3@SiO2 prepared in step S4 was added under stirring, ultrasonically dispersed at 90° C. for 60 min, then naturally cooled to room temperature, allowed to stand for 12 h, centrifuged and filtered, the solid product was washed with ethanol, and vacuum dried at 70° C. for 12 h to obtain a composite filler loaded with a flame retardant: DMMP-MWCNTs@Al2O3@SiO2;

[0044] S5, coating hydrophobic modified membrane:

[0045] S5-1, take 1g of DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, add it to 100mL of ethanol, ultrasonically disperse it for 30min, then add 1.2mL of 3-aminopropyltriethoxysilane, react at 60°C for 4h, centrifuge the product, add the solid product to 150mL of toluene, ultrasonically disperse it for 15min, and obtain a filler dispersion;

[0046] S5-2. Add 0.75g styrene, 0.3g hydroxy silicone oil and 0.15g azobisisobutyronitrile to the filler dispersion, flow nitrogen under stirring for 30 minutes, and react at 65°C for 1 hour; then add 1.25g styrene, 0.95g hydroxy silicone oil and 0.4g azobisisobutyronitrile, raise the temperature to 70°C, and react for 3 hours. After the reaction, the product is centrifuged, and the solid product is washed with ethanol and deionized water in turn, and vacuum dried at 60°C for 12 hours to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

[0047] Preferably, the face paper layer and the corrugated paper core layer, and the corrugated paper core layer and the inner paper layer are bonded by flame retardant adhesive, and the raw materials for preparing the flame retardant adhesive include, by weight: 12-28 parts of bisphenol F epoxy resin, 15-40 parts of bisphenol A epoxy resin, 15-48 parts of polyurethane acrylate, 3-15 parts of hydrogenated terpene resin, 0.2-1 parts of 2-phenylimidazole, 0.3-1 parts of 2-ethylimidazole, 5-30 parts of composite multi-effect enhancer, and 20-70 parts of toluene.

[0048] Preferably, the surface paper layer, the corrugated paper core layer and the inner paper layer are prepared from the same raw materials, and are all prepared from the following components in parts by weight:

[0049] 40-65 parts of lignin fiber;

[0050] 5-27 parts corn starch;

[0051] 5-15 parts of oxidized starch

[0052] 6-48 parts corn stalk powder;

[0053] 3-12 parts of polyvinyl alcohol;

[0054] 2-16 parts of polyacrylamide;

[0055] 2-8 parts of carboxymethyl cellulose

[0056] 180-500 parts of water.

[0057] The second aspect of the present invention provides a method for preparing the waterproof and flame-retardant high-performance composite corrugated paper as described above, comprising the following steps:

[0058] 1) adding lignin fiber, corn straw powder, oxidized starch and corn straw powder into water, stirring evenly and then crushing, passing through a 50-100 mesh sieve, then adding polyvinyl alcohol, polyacrylamide and carboxymethyl cellulose, beating at 100-350 rpm and 60-80° C. for 15-60 min, and then standing for 1-3 h to obtain pulp liquid;

[0059] 2) Drying and shaping the pulp liquid to prepare a surface paper layer and a lining paper layer; Making the pulp liquid into corrugated base paper, and then corrugating and shaping it to obtain a corrugated paper core layer;

[0060] 3) adding the composite multi-effect enhancer to acetone, ultrasonically dispersing for 15-90 minutes, then adding bisphenol A epoxy resin, methyl silicone resin, tetraethylene pentamine, and chlorinated paraffin, stirring at a speed of 1000-4000 rpm for 5-20 minutes to obtain a waterproof and antistatic composite enhanced coating;

[0061] The composite multi-effect enhancer is added to toluene, ultrasonically dispersed for 30-60 minutes, then bisphenol F epoxy resin, bisphenol A epoxy resin, polyurethane acrylate, hydrogenated terpene resin are added, stirred for 15-45 minutes, and finally 2-phenylimidazole and 2-ethylimidazole are added, stirred for 5-30 minutes to obtain a flame retardant adhesive;

[0062] 4) Apply flame retardant glue on the inner surface of the face paper layer and the outer surface of the inner paper layer respectively, then bond the inner surface of the face paper layer to the outer surface of the corrugated paper core layer, and bond the outer surface of the inner paper layer to the inner surface of the corrugated paper core layer, compact with a flattening roller, and dry at 60-85°C for 15-120 minutes;

[0063] A waterproof and antistatic composite reinforced coating is sprayed on the outer surface of the surface paper layer and the inner surface of the inner paper layer, respectively, with a spraying thickness of 0.2-1 mm, and cured at room temperature for 4-8 hours, and then cured at 70-85°C for 1-3 hours to form an outer waterproof and antistatic composite reinforced coating and an inner waterproof and antistatic reinforced composite coating, respectively, to finally obtain the waterproof, flame-retardant, high-performance composite corrugated paper.

[0064] The beneficial effects of the present invention are:

[0065] The waterproof and flame-retardant high-performance composite corrugated paper of the present invention can give the surface excellent waterproof and antistatic properties, and can also improve the flame retardant ability by coating the waterproof and antistatic composite reinforcing coating on the surface paper layer and the inner paper layer; further, the surface paper layer, the corrugated paper core layer and the inner paper layer are bonded by a homemade flame retardant glue, so that the flame retardant performance can be further improved and the overall strength can be improved.

[0066] The composite multi-effect enhancer in the present invention has multi-effect improvement functions, and can improve strength, flame retardant performance, waterproof performance and antistatic performance. By adding it to the waterproof and antistatic composite enhanced coating and flame retardant glue at the same time, it can give the prepared corrugated paper surface excellent waterproof performance and antistatic performance, and can also effectively improve the overall strength of the corrugated paper; at the same time, with the help of the structural system formed by the composite multi-effect enhancer, through the flame retardant sustained release effect and the performance of adaptive release of flame retardant active ingredients, it can maintain long-term flame retardant performance, thereby effectively solving the problem that the flame retardant is easy to lose, migrate or cause other performance reduction of the corrugated paper in the corrugated paper system. In the composite multi-effect enhancer system, each functional component plays a role in mutual cooperation and synergistic enhancement, which has significant help for the waterproof performance, antistatic performance, flame retardant performance and mechanical strength of the corrugated paper system. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 The test results of the sustained release performance of dimethyl methylphosphonate of the composite multi-effect enhancer prepared in Example 1;

[0068] Figure 2 The test results of the relationship between the aluminum doping amount in the composite multi-effect enhancer and the surface contact angle of the coating;

[0069] Figure 3 is the test result of the contact angle in the present invention;

[0070] Figure 4 The flame retardant performance test results of the present invention;

[0071] Figure 5 The test results of the antistatic performance in the present invention;

[0072] Figure 6 is the test result of the bursting strength in the present invention;

[0073] Figure 7 is the test result of the edge compression strength in the present invention;

[0074] Figure 8 This is the test result of the bonding strength in the present invention. DETAILED DESCRIPTION

[0075] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0076] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0077] The test methods used in the following examples are conventional methods unless otherwise specified. The materials and reagents used in the following examples are all commercially available unless otherwise specified. In the following examples, if no specific conditions are specified, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used, if the manufacturer is not specified, are all conventional products that can be purchased commercially.

[0078] The present invention provides a waterproof and flame-retardant high-performance composite corrugated paper, comprising an outer waterproof and antistatic composite enhanced coating, a surface paper layer, a corrugated paper core layer, a lining paper layer, and an inner waterproof and antistatic enhanced composite coating, which are sequentially arranged from the outside to the inside;

[0079] The outer waterproof antistatic composite enhanced coating and the inner waterproof antistatic enhanced composite coating are both obtained by coating the waterproof antistatic composite enhanced coating and then curing it. The waterproof antistatic composite enhanced coating includes the following raw material components in parts by weight:

[0080] 55-75 parts of bisphenol A epoxy resin, 10-24 parts of methyl silicone resin, 2-6.5 parts of tetraethylene pentamine, 3-12 parts of chlorinated paraffin, 3-18 parts of composite multi-effect enhancer, and 40-70 parts of acetone.

[0081] In the present invention, the composite multi-effect enhancer is prepared by the following steps:

[0082] S1. Preparation of acidified carbon nanotubes:

[0083] The multi-walled carbon nanotubes are added to a mixed acid solution consisting of 95 wt% concentrated sulfuric acid and 65 wt% concentrated nitric acid, ultrasonicated, then stirred and refluxed under heating, filtered after cooling to room temperature, washed with deionized water until neutral, and vacuum dried to obtain acidified carbon nanotubes;

[0084] S2. Preparation of porous silica microspheres:

[0085] S2-1, adding hexadecyltrimethylammonium bromide and 1,3,5-trimethylbenzene to an alcohol solution consisting of isopropanol and deionized water, ultrasonically dispersing, adding ammonia water, and ultrasonically dispersing;

[0086] S2-2, adding ethyl orthosilicate to the mixture obtained in step S2-1 under stirring, reacting under heating, filtering after the reaction, washing the solid product, and calcining under air atmosphere to obtain porous silica microspheres.

[0087] S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler:

[0088] S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler:

[0089] S3-1, taking porous silica microspheres and adding them into an ethanol aqueous solution composed of deionized water and ethanol, ultrasonically dispersing them, then adding Al(NO3)3·9H2O and stirring to obtain a microsphere dispersion;

[0090] S3-2, adding the acidified carbon nanotubes into deionized water, and dispersing by ultrasonication to obtain a carbon nanotube dispersion;

[0091] S3-3, under stirring, adding the carbon nanotube dispersion to the microsphere dispersion, stirring, transferring the obtained mixture to a reactor, reacting under heating, cooling to room temperature after the reaction, centrifuging, filtering, washing the solid product, and vacuum drying to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2;

[0092] S4. Loading flame retardant on MWCNTs@Al2O3@SiO2:

[0093] Take dimethyl methylphosphonate and add it to deionized water, stir it, add the MWCNTs@Al2O3@SiO2 prepared in step S3 under stirring, ultrasonically disperse it, then naturally cool it to room temperature, let it stand, centrifuge and filter it, wash the solid product with ethanol, and vacuum dry it to obtain a composite filler loaded with a flame retardant: DMMP-MWCNTs@Al2O3@SiO2.

[0094] S5. Coating a hydrophobic modified film on the composite filler loaded with flame retardant:

[0095] S5-1, S5-1, take the DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, add it to ethanol, ultrasonically disperse it, then add 3-aminopropyltriethoxysilane, react under heating, centrifuge the product, add the solid product to toluene, ultrasonically disperse it, and obtain a filler dispersion;

[0096] S5-2. Add styrene, hydroxy silicone oil and azobisisobutyronitrile to the filler dispersion, pass nitrogen under stirring, and heat to react; then add styrene, hydroxy silicone oil and azobisisobutyronitrile, and heat to react. After the reaction is completed, the product is centrifuged, the solid product is washed, and vacuum dried to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

[0097] In the present invention, the surface paper layer and the corrugated paper core layer, and the corrugated paper core layer and the inner paper layer are bonded by flame retardant adhesive, and the raw materials for preparing the flame retardant adhesive include, by weight, 12-28 parts of bisphenol F epoxy resin, 15-40 parts of bisphenol A epoxy resin, 15-48 parts of polyurethane acrylate, 3-15 parts of hydrogenated terpene resin, 0.2-1 parts of 2-phenylimidazole, 0.3-1 parts of 2-ethylimidazole, 5-30 parts of composite multi-effect enhancer, and 20-70 parts of toluene.

[0098] In the present invention, the surface paper layer, the corrugated paper core layer and the inner paper layer are prepared from the same raw materials, and are all prepared from the following components in parts by weight:

[0099] 40-65 parts of lignin fiber;

[0100] 5-27 parts corn starch;

[0101] 5-15 parts of oxidized starch

[0102] 6-48 parts corn stalk powder;

[0103] 3-12 parts of polyvinyl alcohol;

[0104] 2-16 parts of polyacrylamide;

[0105] 2-8 parts of carboxymethyl cellulose

[0106] 180-500 parts of water.

[0107] In the present invention, the preparation method of waterproof and flame-retardant high-performance composite corrugated paper comprises the following steps:

[0108] 1) adding lignin fiber, corn straw powder, oxidized starch and corn straw powder into water, stirring evenly and then crushing, passing through a 50-100 mesh sieve, then adding polyvinyl alcohol, polyacrylamide and carboxymethyl cellulose, beating at 100-350 rpm and 60-80° C. for 15-60 min, and then standing for 1-3 h to obtain pulp liquid;

[0109] 2) Drying and shaping the pulp liquid to prepare a surface paper layer and a lining paper layer; Making the pulp liquid into corrugated base paper, and then corrugating and shaping it to obtain a corrugated paper core layer;

[0110] 3) adding the composite multi-effect enhancer to acetone, ultrasonically dispersing for 15-90 minutes, then adding bisphenol A epoxy resin, methyl silicone resin, tetraethylene pentamine, and chlorinated paraffin, stirring at a speed of 1000-4000 rpm for 5-20 minutes to obtain a waterproof and antistatic composite enhanced coating;

[0111] The composite multi-effect enhancer is added to toluene, ultrasonically dispersed for 30-60 minutes, then bisphenol F epoxy resin, bisphenol A epoxy resin, polyurethane acrylate, hydrogenated terpene resin are added, stirred for 15-45 minutes, and finally 2-phenylimidazole and 2-ethylimidazole are added, stirred for 5-30 minutes to obtain a flame retardant adhesive;

[0112] 4) Apply flame retardant glue on the inner surface of the face paper layer and the outer surface of the inner paper layer respectively, then bond the inner surface of the face paper layer to the outer surface of the corrugated paper core layer, and bond the outer surface of the inner paper layer to the inner surface of the corrugated paper core layer, compact with a flattening roller, and dry at 60-85°C for 15-120 minutes;

[0113] The outer surface of the face paper layer and the inner surface of the lining paper layer are sprayed with a waterproof and antistatic composite reinforced coating with a spraying thickness of 0.2-1mm. The coating is cured at room temperature for 4-8 hours and then cured at 70-85°C for 1-3 hours to form an outer waterproof and antistatic composite reinforced coating and an inner waterproof and antistatic reinforced composite coating, respectively, to finally obtain a waterproof and flame-retardant high-performance composite corrugated paper.

[0114] In the present invention, the composite multi-effect enhancer has multi-effect improvement functions, and can improve strength, flame retardant performance, waterproof performance and antistatic performance. By adding it to the waterproof and antistatic composite enhanced coating and flame retardant glue at the same time, it can give the prepared corrugated paper surface excellent waterproof and antistatic performance, and at the same time can effectively improve the overall strength of the corrugated paper. At the same time, with the help of the structural system formed by the composite multi-effect enhancer, it can give it the performance of adaptively releasing flame retardant active ingredients, thereby effectively solving the problem that the flame retardant is easy to lose, migrate or cause other performance reductions of the corrugated paper in the corrugated paper system. The following is an explanation of its mechanism of action in conjunction with its specific preparation process to facilitate the understanding of the present invention.

[0115] Firstly, the present invention prepares carboxyl-modified acidified carbon nanotubes, whose surfaces have abundant carboxyl functional groups, and prepares porous silica microspheres with abundant pore structures;

[0116] Then, porous silica is grafted onto carbon nanotubes through a hydrothermal reaction, and a large amount of Al2O3 particles are modified on the surface of the porous silica to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2. In this process, Al3+ is first mixed with a porous silica microsphere dispersion, and Al3+ is loaded onto the surface of the porous silica microsphere by combining with the silanol groups on the surface of the porous silica microsphere. Then, after mixing with the acidified carbon nanotubes, Al3+ combines with the carboxyl groups on the surface of the acidified carbon nanotubes through coordination and / or electrostatic adsorption, so that the acidified carbon nanotubes are combined with the porous silica microspheres through the intermediate bridging effect of Al3+. Then, Al3+ forms Al2O3 particles through a hydrothermal reaction, and the acidified carbon nanotubes are firmly combined with the porous silica microspheres to obtain MWCNTs@Al2O3@SiO2.

[0117] Then, the flame retardant dimethyl methylphosphonate was loaded on MWCNTs@Al2O3@SiO2 by the impregnation method. The pore structure of the porous silica microspheres can achieve a large amount of dimethyl methylphosphonate loading, and the hollow structure of the acidified carbon nanotubes can also adsorb and load a certain amount of dimethyl methylphosphonate, thus obtaining a composite filler loaded with flame retardant: DMMP-MWCNTs@Al2O3@SiO2;

[0118] Finally, a polysiloxane-modified polystyrene composite membrane (hydrophobic modified membrane) was coated on DMMP-MWCNTs@Al2O3@SiO2 to obtain the final composite multi-effect enhancer: ATP-MWCNTs@Al2O3@SiO2-PS-PDMS.

[0119] 1. In the composite multi-effect enhancer system, the acidified carbon nanotubes can effectively improve the electrical conductivity and mechanical strength of the material, while also providing a certain dimethyl methylphosphonate loading function, and it itself also has a certain flame retardant effect; the addition of the acidified carbon nanotubes can give the final prepared external waterproof and antistatic composite enhanced coating and the internal waterproof and antistatic enhanced composite coating good antistatic properties.

[0120] 2. After dimethyl methylphosphonate is loaded onto MWCNTs@Al2O3@SiO2, it is then coated with a hydrophobic modified membrane. On the one hand, it can give the system excellent sustained-release properties, that is, after being added to the corrugated paper system, dimethyl methylphosphonate can be released into the system slowly and for a long time, and can maintain a long-lasting flame retardant effect. At the same time, it can also avoid the negative impact on other properties of the system when the flame retardant is directly added to the system at one time, as well as the loss and migration of the flame retardant. On the other hand, the coating treatment of the hydrophobic modified membrane not only enhances the sustained-release control effect, but also provides the function of adaptively adjusting the release of the flame retardant. Specifically, when the temperature rises due to a fire, the hydrophobic modified membrane will soften or even melt. At this time, the release rate of the internal flame retardant will be significantly accelerated, thereby rapidly improving the flame retardant performance to achieve the effect of preventing the spread of the fire.

[0121] 3. In the composite multi-effect enhancer system, the coating of the hydrophobic modified membrane also has the following effects:

[0122] (1) Significantly improve the compatibility of the composite multi-effect enhancer with the waterproof and antistatic composite enhanced coating system and the flame retardant adhesive system, overcome the poor compatibility of inorganic material acidified carbon nanotubes and porous silica microspheres with the organic resin system, and ensure that the composite multi-effect enhancer can be evenly dispersed in the organic resin system;

[0123] (2) The hydrophobic modified membrane is a polystyrene composite membrane modified by polysiloxane. Polysiloxane is derived from the silicon-oxygen bond (Si-O bond) and alkyl group in its molecular structure, which makes it have excellent hydrophobicity. The coating of the hydrophobic modified membrane gives the composite multi-effect enhancer good hydrophobic properties. Its addition to the waterproof and antistatic composite enhanced coating system makes the final prepared external waterproof and antistatic composite enhanced coating and internal waterproof and antistatic enhanced composite coating have excellent hydrophobic properties.

[0124] 4. In this composite multi-effect enhancer system, the doped Al2O3 not only plays a bridging role in the preparation process, but also has the following effects: Al2O3 forms a slightly convex spherical structure on the surface of porous silica microspheres, which can increase the surface roughness and thus improve the hydrophobicity; in addition, Al2O3, as a connecting node between acidified carbon nanotubes and porous silica microspheres, can improve the mechanical strength of the system and play a role in improving the cohesive strength in flame retardant rubber.

[0125] Therefore, in the composite multi-effect enhancer system of the present invention, each functional component plays a role of cooperating with each other and synergistically enhancing the effect, which has a significant help in the waterproof performance, antistatic performance, flame retardant performance and mechanical strength of the corrugated paper system.

[0126] The above is the overall concept of the present invention, and detailed embodiments and comparative examples are provided below on the basis of the overall concept of the present invention to further illustrate the present invention.

[0127] The main raw materials of the following examples and comparative examples are described as follows:

[0128] Bisphenol A epoxy resin, bisphenol F epoxy resin, Suzhou Senfeida Chemical Co., Ltd.;

[0129] Methyl silicone resin, model SI-MQ102, Laiyang Shengbang Silicone Technology Co., Ltd.;

[0130] Tetraethylenepentamine, chlorinated paraffin, Shanghai Hongzhuang Chemical Technology Co., Ltd.;

[0131] Polyurethane acrylate, polyurethane acrylate oligomer resin A2116, Hubei Handafei Biotechnology Co., Ltd.;

[0132] Hydrogenated terpene resin, Shandong Xinghai Chemical Co., Ltd.;

[0133] 2-phenylimidazole, Jiangsu Rayen Environmental Protection Technology Co., Ltd.;

[0134] 2-Ethylimidazole, Nantong Runfeng Petrochemical Co., Ltd.;

[0135] Multi-walled carbon nanotubes, average length 5um, diameter 60nm, Guangzhou Hongwu Materials Technology Co., Ltd.;

[0136] Hexadecyltrimethylammonium bromide, Jiangsu Rayen Environmental Protection Technology Co., Ltd.;

[0137] Dimethyl methylphosphonate (DMMP), Jiangsu Runfeng Synthetic Technology Co., Ltd.;

[0138] 3-Aminopropyltriethoxysilane, Nanjing Xuanhao New Material Technology Co., Ltd.;

[0139] Styrene, Jiangsu Runfeng Synthetic Technology Co., Ltd.;

[0140] Hydroxy silicone oil, SI-205 hydroxy silicone oil, Laiyang Shengbang Silicone Technology Co., Ltd.;

[0141] Lignin fiber, Xuzhou Yihuiyang New Materials Co., Ltd.;

[0142] Corn starch, Xuzhou Yihuiyang New Materials Co., Ltd.;

[0143] Oxidized starch, Jiangsu Caiwei Biotechnology Co., Ltd.;

[0144] Corn straw powder, Henan Mingjie Animal Husbandry Co., Ltd.;

[0145] Polyvinyl alcohol, polyacrylamide, Jiangsu Rayen Environmental Protection Technology Co., Ltd.;

[0146] Carboxymethyl cellulose, Shanghai Hongzhuang Chemical Technology Co., Ltd.

[0147] Example 1

[0148] A waterproof and flame-retardant high-performance composite corrugated paper comprises an outer waterproof and antistatic composite enhanced coating, a surface paper layer, a corrugated paper core layer, a lining paper layer and an inner waterproof and antistatic enhanced composite coating which are arranged in sequence from the outside to the inside.

[0149] Among them, the outer waterproof and antistatic composite reinforced coating and the inner waterproof and antistatic reinforced composite coating are both obtained by coating the waterproof and antistatic composite reinforced coating and then curing. The waterproof and antistatic composite reinforced coating includes the following raw material components in parts by weight: 62 parts of bisphenol A epoxy resin, 18 parts of methyl silicone resin, 3.5 parts of tetraethylene pentamine, 4.8 parts of chlorinated paraffin, 13 parts of composite multi-effect enhancer, and 55 parts of acetone.

[0150] Among them, the surface paper layer and the corrugated paper core layer, and the corrugated paper core layer and the inner paper layer are bonded by flame retardant adhesive. The raw materials for preparing the flame retardant adhesive include, by weight: 22 parts of bisphenol F epoxy resin, 36 parts of bisphenol A epoxy resin, 27 parts of polyurethane acrylate, 7.5 parts of hydrogenated terpene resin, 0.35 parts of 2-phenylimidazole, 0.4 parts of 2-ethylimidazole, 20 parts of composite multi-effect enhancer, and 50 parts of toluene.

[0151] The composite multi-effect enhancer is prepared by the following steps:

[0152] S1. Preparation of acidified carbon nanotubes:

[0153] 2 g of multi-walled carbon nanotubes were added to 200 mL of a mixed acid solution consisting of 95 wt% concentrated sulfuric acid and 65 wt% concentrated nitric acid in a volume ratio of 3:1, ultrasonicated for 2 h, then stirred and refluxed at 80 ° C for 12 h, cooled to room temperature and filtered, washed with deionized water until neutral, and vacuum dried at 90 ° C for 8 h to obtain acidified carbon nanotubes;

[0154] S2. Preparation of porous silica microspheres:

[0155] S2-1, take 2g of hexadecyltrimethylammonium bromide (CTAB) and 0.85g of 1,3,5-trimethylbenzene, add them into 360mL of an alcohol solution composed of isopropanol and deionized water in a volume ratio of 1:1, ultrasonically disperse for 5min, add 5mL of 25% ammonia water, and ultrasonically disperse for 15min;

[0156] S2-2. Add 12.5 mL of tetraethyl orthosilicate to the mixture obtained in step S2-1 under stirring, and react at 55° C. for 12 h. After the reaction is completed, filter the solid product, wash it with ethanol and deionized water in sequence, and calcine it at 550° C. in air atmosphere for 5 h to obtain porous silica microspheres.

[0157] S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler:

[0158] S3-1, take 1g of porous silica microspheres and add them into an ethanol aqueous solution consisting of 80mL of deionized water and 120mL of ethanol, ultrasonically disperse for 30min, then add 1.125g of Al(NO3)3·9H2O, stir at 600rpm for 45min to obtain a microsphere dispersion;

[0159] S3-2, taking 0.8 g of acidified carbon nanotubes and adding them into 100 mL of deionized water, and ultrasonically dispersing them for 30 min to obtain a carbon nanotube dispersion;

[0160] S3-3, under stirring, adding the carbon nanotube dispersion to the microsphere dispersion, stirring for 60 minutes, transferring the obtained mixture to a reactor, reacting at 200°C for 12 hours, cooling to room temperature after the reaction, centrifuging and filtering, washing the solid product with deionized water, and vacuum drying at 90°C for 8 hours to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2;

[0161] S4, loaded flame retardant:

[0162] 2 g of dimethyl methylphosphonate was added to 100 mL of deionized water, stirred at 90° C. for 15 min, 1.5 g of MWCNTs@Al2O3@SiO2 prepared in step S4 was added under stirring, ultrasonically dispersed at 90° C. for 60 min, then naturally cooled to room temperature, allowed to stand for 12 h, centrifuged and filtered, the solid product was washed with ethanol, and vacuum dried at 70° C. for 12 h to obtain a composite filler loaded with a flame retardant: DMMP-MWCNTs@Al2O3@SiO2;

[0163] S5, coating hydrophobic modified membrane:

[0164] S5-1, take 1g of DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, add it to 100mL of ethanol, ultrasonically disperse it for 30min, then add 1.2mL of 3-aminopropyltriethoxysilane, react at 60°C for 4h, centrifuge the product, add the solid product to 150mL of toluene, ultrasonically disperse it for 15min, and obtain a filler dispersion;

[0165] S5-2. Add 0.75g styrene, 0.3g hydroxy silicone oil and 0.15g azobisisobutyronitrile (AIBN) to the filler dispersion, flow nitrogen for 30 minutes with stirring, and react at 65°C for 1 hour; then add 1.25g styrene, 0.95g hydroxy silicone oil and 0.4g azobisisobutyronitrile (AIBN), raise the temperature to 70°C, and react for 3 hours. After the reaction, the product is centrifuged, and the solid product is washed with ethanol and deionized water in turn, and vacuum dried at 60°C for 12 hours to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

[0166] The surface paper layer, the corrugated paper core layer and the inner paper layer are prepared from the same raw materials, and are all prepared from the following components by weight:

[0167]

[0168] The preparation method of the waterproof and flame-retardant high-performance composite corrugated paper comprises the following steps:

[0169] 1) adding lignin fiber, corn straw powder, oxidized starch and corn straw powder into water, stirring evenly and then crushing, passing through a 100-mesh sieve, then adding polyvinyl alcohol, polyacrylamide and carboxymethyl cellulose, beating at 200 rpm and 70° C. for 30 min, and then standing for 2 h to obtain pulp;

[0170] 2) Drying and shaping the pulp liquid to prepare a surface paper layer and a lining paper layer; Making the pulp liquid into corrugated base paper, and then corrugating and shaping it to obtain a corrugated paper core layer;

[0171] 3) adding the composite multi-effect enhancer to acetone, ultrasonically dispersing for 60 minutes, then adding bisphenol A epoxy resin, methyl silicone resin, tetraethylene pentamine, and chlorinated paraffin, stirring at 2000 rpm for 10 minutes, to obtain a waterproof and antistatic composite reinforced coating;

[0172] The composite multi-effect enhancer was added to toluene, and ultrasonically dispersed for 45 minutes, and then bisphenol F epoxy resin, bisphenol A epoxy resin, polyurethane acrylate, and hydrogenated terpene resin were added and stirred for 30 minutes, and finally 2-phenylimidazole and 2-ethylimidazole were added and stirred for 15 minutes to obtain a flame retardant adhesive;

[0173] 4) Apply flame retardant glue on the inner surface of the face paper layer and the outer surface of the inner paper layer respectively, then bond the inner surface of the face paper layer to the outer surface of the corrugated paper core layer, and bond the outer surface of the inner paper layer to the inner surface of the corrugated paper core layer, compact with a flattening roller, and dry at 70°C for 60 minutes;

[0174] The waterproof and antistatic composite reinforced coating is sprayed on the outer surface of the surface paper layer and the inner surface of the inner paper layer, respectively, with a spraying thickness of 0.6 mm. The coating is cured at room temperature for 6 hours and then at 80°C for 1.5 hours to form an outer waterproof and antistatic composite reinforced coating and an inner waterproof and antistatic reinforced composite coating, respectively, and finally a waterproof and flame-retardant high-performance composite corrugated paper is obtained.

[0175] Example 2

[0176] A waterproof and flame-retardant high-performance composite corrugated paper comprises an outer waterproof and antistatic composite enhanced coating, a surface paper layer, a corrugated paper core layer, a lining paper layer and an inner waterproof and antistatic enhanced composite coating which are arranged in sequence from the outside to the inside.

[0177] Among them, the outer waterproof and antistatic composite reinforced coating and the inner waterproof and antistatic reinforced composite coating are both obtained by coating the waterproof and antistatic composite reinforced coating and then curing. The waterproof and antistatic composite reinforced coating includes the following raw material components in parts by weight: 65 parts of bisphenol A epoxy resin, 18 parts of methyl silicone resin, 3.5 parts of tetraethylene pentamine, 5 parts of chlorinated paraffin, 11 parts of composite multi-effect enhancer, and 55 parts of acetone.

[0178] Among them, the surface paper layer and the corrugated paper core layer, and the corrugated paper core layer and the inner paper layer are bonded by flame retardant adhesive. The raw materials for preparing the flame retardant adhesive include, by weight: 20 parts of bisphenol F epoxy resin, 38 parts of bisphenol A epoxy resin, 27 parts of polyurethane acrylate, 7.5 parts of hydrogenated terpene resin, 0.35 parts of 2-phenylimidazole, 0.4 parts of 2-ethylimidazole, 18 parts of composite multi-effect enhancer, and 50 parts of toluene.

[0179] The composite multi-effect enhancer is prepared by the following steps:

[0180] S1. Preparation of acidified carbon nanotubes:

[0181] 2 g of multi-walled carbon nanotubes were added to 200 mL of a mixed acid solution consisting of 95 wt% concentrated sulfuric acid and 65 wt% concentrated nitric acid in a volume ratio of 3:1, ultrasonicated for 2 h, then stirred and refluxed at 80 ° C for 12 h, cooled to room temperature and filtered, washed with deionized water until neutral, and vacuum dried at 90 ° C for 8 h to obtain acidified carbon nanotubes;

[0182] S2. Preparation of porous silica microspheres:

[0183] S2-1, take 2g of hexadecyltrimethylammonium bromide (CTAB) and 0.85g of 1,3,5-trimethylbenzene, add them into 360mL of an alcohol solution composed of isopropanol and deionized water in a volume ratio of 1:1, ultrasonically disperse for 5min, add 5mL of 25% ammonia water, and ultrasonically disperse for 15min;

[0184] S2-2. Add 12.5 mL of tetraethyl orthosilicate to the mixture obtained in step S2-1 under stirring, and react at 55° C. for 12 h. After the reaction is completed, filter the solid product, wash it with ethanol and deionized water in sequence, and calcine it at 550° C. in air atmosphere for 5 h to obtain porous silica microspheres.

[0185] S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler:

[0186] S3-1, take 1g of porous silica microspheres and add them into an ethanol aqueous solution consisting of 80mL of deionized water and 120mL of ethanol, ultrasonically disperse for 30min, then add 1.125g of Al(NO3)3·9H2O, stir at 600rpm for 45min to obtain a microsphere dispersion;

[0187] S3-2, taking 0.8 g of acidified carbon nanotubes and adding them into 100 mL of deionized water, and ultrasonically dispersing them for 30 min to obtain a carbon nanotube dispersion;

[0188] S3-3, under stirring, adding the carbon nanotube dispersion to the microsphere dispersion, stirring for 60 minutes, transferring the obtained mixture to a reactor, reacting at 200°C for 12 hours, cooling to room temperature after the reaction, centrifuging and filtering, washing the solid product with deionized water, and vacuum drying at 90°C for 8 hours to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2;

[0189] S4, loaded flame retardant:

[0190] 2 g of dimethyl methylphosphonate was added to 100 mL of deionized water, stirred at 90° C. for 15 min, 1.5 g of MWCNTs@Al2O3@SiO2 prepared in step S4 was added under stirring, ultrasonically dispersed at 90° C. for 60 min, then naturally cooled to room temperature, allowed to stand for 12 h, centrifuged and filtered, the solid product was washed with ethanol, and vacuum dried at 70° C. for 12 h to obtain a composite filler loaded with a flame retardant: DMMP-MWCNTs@Al2O3@SiO2;

[0191] S5, coating hydrophobic modified membrane:

[0192] S5-1, take 1g of DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, add it to 100mL of ethanol, ultrasonically disperse it for 30min, then add 1.2mL of 3-aminopropyltriethoxysilane, react at 60°C for 4h, centrifuge the product, add the solid product to 150mL of toluene, ultrasonically disperse it for 15min, and obtain a filler dispersion;

[0193] S5-2. Add 0.75g styrene, 0.3g hydroxy silicone oil and 0.15g azobisisobutyronitrile (AIBN) to the filler dispersion, flow nitrogen for 30 minutes with stirring, and react at 65°C for 1 hour; then add 1.25g styrene, 0.95g hydroxy silicone oil and 0.4g azobisisobutyronitrile (AIBN), raise the temperature to 70°C, and react for 3 hours. After the reaction, the product is centrifuged, and the solid product is washed with ethanol and deionized water in turn, and vacuum dried at 60°C for 12 hours to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

[0194] The surface paper layer, the corrugated paper core layer and the inner paper layer are prepared from the same raw materials, and are all prepared from the following components by weight:

[0195]

[0196] The preparation method of the waterproof and flame-retardant high-performance composite corrugated paper comprises the following steps:

[0197] 1) adding lignin fiber, corn straw powder, oxidized starch and corn straw powder into water, stirring evenly and then crushing, passing through a 100-mesh sieve, then adding polyvinyl alcohol, polyacrylamide and carboxymethyl cellulose, beating at 200 rpm and 70° C. for 30 min, and then standing for 2 h to obtain pulp;

[0198] 2) Drying and shaping the pulp liquid to prepare a surface paper layer and a lining paper layer; Making the pulp liquid into corrugated base paper, and then corrugating and shaping it to obtain a corrugated paper core layer;

[0199] 3) adding the composite multi-effect enhancer to acetone, ultrasonically dispersing for 60 minutes, then adding bisphenol A epoxy resin, methyl silicone resin, tetraethylene pentamine, and chlorinated paraffin, stirring at 2000 rpm for 10 minutes, to obtain a waterproof and antistatic composite reinforced coating;

[0200] The composite multi-effect enhancer was added to toluene, and ultrasonically dispersed for 45 minutes, and then bisphenol F epoxy resin, bisphenol A epoxy resin, polyurethane acrylate, and hydrogenated terpene resin were added and stirred for 30 minutes, and finally 2-phenylimidazole and 2-ethylimidazole were added and stirred for 15 minutes to obtain a flame retardant adhesive;

[0201] 4) Apply flame retardant glue on the inner surface of the face paper layer and the outer surface of the inner paper layer respectively, then bond the inner surface of the face paper layer to the outer surface of the corrugated paper core layer, and bond the outer surface of the inner paper layer to the inner surface of the corrugated paper core layer, compact with a flattening roller, and dry at 70°C for 60 minutes;

[0202] The waterproof and antistatic composite reinforced coating is sprayed on the outer surface of the surface paper layer and the inner surface of the inner paper layer, respectively, with a spraying thickness of 0.6 mm. The coating is cured at room temperature for 6 hours and then at 80°C for 1.5 hours to form an outer waterproof and antistatic composite reinforced coating and an inner waterproof and antistatic reinforced composite coating, respectively, and finally a waterproof and flame-retardant high-performance composite corrugated paper is obtained.

[0203] Example 3

[0204] A waterproof and flame-retardant high-performance composite corrugated paper comprises an outer waterproof and antistatic composite enhanced coating, a surface paper layer, a corrugated paper core layer, a lining paper layer and an inner waterproof and antistatic enhanced composite coating which are arranged in sequence from the outside to the inside.

[0205] Among them, the outer waterproof and antistatic composite reinforced coating and the inner waterproof and antistatic reinforced composite coating are both obtained by coating the waterproof and antistatic composite reinforced coating and then curing. The waterproof and antistatic composite reinforced coating includes the following raw material components in parts by weight: 60 parts of bisphenol A epoxy resin, 20 parts of methyl silicone resin, 3.8 parts of tetraethylene pentamine, 4.8 parts of chlorinated paraffin, 13 parts of composite multi-effect enhancer, and 55 parts of acetone.

[0206] Among them, the surface paper layer and the corrugated paper core layer, and the corrugated paper core layer and the inner paper layer are bonded by flame retardant adhesive. The raw materials for preparing the flame retardant adhesive include, by weight: 25 parts of bisphenol F epoxy resin, 33 parts of bisphenol A epoxy resin, 28 parts of polyurethane acrylate, 7 parts of hydrogenated terpene resin, 0.3 parts of 2-phenylimidazole, 0.45 parts of 2-ethylimidazole, 20 parts of composite multi-effect enhancer, and 50 parts of toluene.

[0207] The composite multi-effect enhancer is prepared by the following steps:

[0208] S1. Preparation of acidified carbon nanotubes:

[0209] 2 g of multi-walled carbon nanotubes were added to 200 mL of a mixed acid solution consisting of 95 wt% concentrated sulfuric acid and 65 wt% concentrated nitric acid in a volume ratio of 3:1, ultrasonicated for 2 h, then stirred and refluxed at 80 ° C for 12 h, cooled to room temperature and filtered, washed with deionized water until neutral, and vacuum dried at 90 ° C for 8 h to obtain acidified carbon nanotubes;

[0210] S2. Preparation of porous silica microspheres:

[0211] S2-1, take 2g of hexadecyltrimethylammonium bromide (CTAB) and 0.85g of 1,3,5-trimethylbenzene, add them into 360mL of an alcohol solution composed of isopropanol and deionized water in a volume ratio of 1:1, ultrasonically disperse for 5min, add 5mL of 25% ammonia water, and ultrasonically disperse for 15min;

[0212] S2-2. Add 12.5 mL of tetraethyl orthosilicate to the mixture obtained in step S2-1 under stirring, and react at 55° C. for 12 h. After the reaction is completed, filter the solid product, wash it with ethanol and deionized water in sequence, and calcine it at 550° C. in air atmosphere for 5 h to obtain porous silica microspheres.

[0213] S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler:

[0214] S3-1, take 1g of porous silica microspheres and add them into an ethanol aqueous solution consisting of 80mL of deionized water and 120mL of ethanol, ultrasonically disperse for 30min, then add 1.125g of Al(NO3)3·9H2O, stir at 600rpm for 45min to obtain a microsphere dispersion;

[0215] S3-2, taking 0.8 g of acidified carbon nanotubes and adding them into 100 mL of deionized water, and ultrasonically dispersing them for 30 min to obtain a carbon nanotube dispersion;

[0216] S3-3, under stirring, adding the carbon nanotube dispersion to the microsphere dispersion, stirring for 60 minutes, transferring the obtained mixture to a reactor, reacting at 200°C for 12 hours, cooling to room temperature after the reaction, centrifuging and filtering, washing the solid product with deionized water, and vacuum drying at 90°C for 8 hours to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2;

[0217] S4, loaded flame retardant:

[0218] 2 g of dimethyl methylphosphonate was added to 100 mL of deionized water, stirred at 90° C. for 15 min, 1.5 g of MWCNTs@Al2O3@SiO2 prepared in step S4 was added under stirring, ultrasonically dispersed at 90° C. for 60 min, then naturally cooled to room temperature, allowed to stand for 12 h, centrifuged and filtered, the solid product was washed with ethanol, and vacuum dried at 70° C. for 12 h to obtain a composite filler loaded with a flame retardant: DMMP-MWCNTs@Al2O3@SiO2;

[0219] S5, coating hydrophobic modified membrane:

[0220] S5-1, take 1g of DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, add it to 100mL of ethanol, ultrasonically disperse it for 30min, then add 1.2mL of 3-aminopropyltriethoxysilane, react at 60°C for 4h, centrifuge the product, add the solid product to 150mL of toluene, ultrasonically disperse it for 15min, and obtain a filler dispersion;

[0221] S5-2. Add 0.75g styrene, 0.3g hydroxy silicone oil and 0.15g azobisisobutyronitrile (AIBN) to the filler dispersion, flow nitrogen for 30 minutes with stirring, and react at 65°C for 1 hour; then add 1.25g styrene, 0.95g hydroxy silicone oil and 0.4g azobisisobutyronitrile (AIBN), raise the temperature to 70°C, and react for 3 hours. After the reaction, the product is centrifuged, and the solid product is washed with ethanol and deionized water in turn, and vacuum dried at 60°C for 12 hours to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

[0222] The surface paper layer, the corrugated paper core layer and the inner paper layer are prepared from the same raw materials, and are all prepared from the following components by weight:

[0223] 58 parts of lignin fiber;

[0224] 15 parts corn starch;

[0225] 10 parts oxidized starch

[0226] Corn stalk powder 31 parts;

[0227] 7 parts of polyvinyl alcohol;

[0228] Polyacrylamide 5.5 parts;

[0229] 4 parts of carboxymethyl cellulose

[0230] 250 parts of water.

[0231] The preparation method of the waterproof and flame-retardant high-performance composite corrugated paper comprises the following steps:

[0232] 1) adding lignin fiber, corn straw powder, oxidized starch and corn straw powder into water, stirring evenly and then crushing, passing through a 100-mesh sieve, then adding polyvinyl alcohol, polyacrylamide and carboxymethyl cellulose, beating at 200 rpm and 70° C. for 30 min, and then standing for 2 h to obtain pulp;

[0233] 2) Drying and shaping the pulp liquid to prepare a surface paper layer and a lining paper layer; Making the pulp liquid into corrugated base paper, and then corrugating and shaping it to obtain a corrugated paper core layer;

[0234] 3) adding the composite multi-effect enhancer to acetone, ultrasonically dispersing for 60 minutes, then adding bisphenol A epoxy resin, methyl silicone resin, tetraethylene pentamine, and chlorinated paraffin, stirring at 2000 rpm for 10 minutes, to obtain a waterproof and antistatic composite reinforced coating;

[0235] The composite multi-effect enhancer was added to toluene, and ultrasonically dispersed for 45 minutes, and then bisphenol F epoxy resin, bisphenol A epoxy resin, polyurethane acrylate, and hydrogenated terpene resin were added and stirred for 30 minutes, and finally 2-phenylimidazole and 2-ethylimidazole were added and stirred for 15 minutes to obtain a flame retardant adhesive;

[0236] 4) Apply flame retardant glue on the inner surface of the face paper layer and the outer surface of the inner paper layer respectively, then bond the inner surface of the face paper layer to the outer surface of the corrugated paper core layer, and bond the outer surface of the inner paper layer to the inner surface of the corrugated paper core layer, compact with a flattening roller, and dry at 70°C for 60 minutes;

[0237] The waterproof and antistatic composite reinforced coating is sprayed on the outer surface of the surface paper layer and the inner surface of the inner paper layer, respectively, with a spraying thickness of 0.6 mm. The coating is cured at room temperature for 6 hours and then at 80°C for 1.5 hours to form an outer waterproof and antistatic composite reinforced coating and an inner waterproof and antistatic reinforced composite coating, respectively, and finally a waterproof and flame-retardant high-performance composite corrugated paper is obtained.

[0238] Example 4

[0239] A waterproof and flame-retardant high-performance composite corrugated paper comprises an outer waterproof and antistatic composite enhanced coating, a surface paper layer, a corrugated paper core layer, a lining paper layer and an inner waterproof and antistatic enhanced composite coating which are arranged in sequence from the outside to the inside.

[0240] Among them, the outer waterproof and antistatic composite reinforced coating and the inner waterproof and antistatic reinforced composite coating are both obtained by coating the waterproof and antistatic composite reinforced coating and then curing. The waterproof and antistatic composite reinforced coating includes the following raw material components in parts by weight: 64 parts of bisphenol A epoxy resin, 17 parts of methyl silicone resin, 3.5 parts of tetraethylene pentamine, 4.8 parts of chlorinated paraffin, 14 parts of composite multi-effect enhancer, and 55 parts of acetone.

[0241] Among them, the surface paper layer and the corrugated paper core layer, and the corrugated paper core layer and the inner paper layer are bonded by flame retardant adhesive. The raw materials for preparing the flame retardant adhesive include, by weight: 25 parts of bisphenol F epoxy resin, 35 parts of bisphenol A epoxy resin, 27 parts of polyurethane acrylate, 8.5 parts of hydrogenated terpene resin, 0.4 parts of 2-phenylimidazole, 0.4 parts of 2-ethylimidazole, 19 parts of composite multi-effect enhancer, and 50 parts of toluene.

[0242] The composite multi-effect enhancer is prepared by the following steps:

[0243] S1. Preparation of acidified carbon nanotubes:

[0244] 2 g of multi-walled carbon nanotubes were added to 200 mL of a mixed acid solution consisting of 95 wt% concentrated sulfuric acid and 65 wt% concentrated nitric acid in a volume ratio of 3:1, ultrasonicated for 2 h, then stirred and refluxed at 80 ° C for 12 h, cooled to room temperature and filtered, washed with deionized water until neutral, and vacuum dried at 90 ° C for 8 h to obtain acidified carbon nanotubes;

[0245] S2. Preparation of porous silica microspheres:

[0246] S2-1, take 2g of hexadecyltrimethylammonium bromide (CTAB) and 0.85g of 1,3,5-trimethylbenzene, add them into 360mL of an alcohol solution composed of isopropanol and deionized water in a volume ratio of 1:1, ultrasonically disperse for 5min, add 5mL of 25% ammonia water, and ultrasonically disperse for 15min;

[0247] S2-2. Add 12.5 mL of tetraethyl orthosilicate to the mixture obtained in step S2-1 under stirring, and react at 55° C. for 12 h. After the reaction is completed, filter the solid product, wash it with ethanol and deionized water in sequence, and calcine it at 550° C. in air atmosphere for 5 h to obtain porous silica microspheres.

[0248] S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler:

[0249] S3-1, take 1g of porous silica microspheres and add them into an ethanol aqueous solution consisting of 80mL of deionized water and 120mL of ethanol, ultrasonically disperse for 30min, then add 1.125g of Al(NO3)3·9H2O, stir at 600rpm for 45min to obtain a microsphere dispersion;

[0250] S3-2, taking 0.8 g of acidified carbon nanotubes and adding them into 100 mL of deionized water, and ultrasonically dispersing them for 30 min to obtain a carbon nanotube dispersion;

[0251] S3-3, under stirring, adding the carbon nanotube dispersion to the microsphere dispersion, stirring for 60 minutes, transferring the obtained mixture to a reactor, reacting at 200°C for 12 hours, cooling to room temperature after the reaction, centrifuging and filtering, washing the solid product with deionized water, and vacuum drying at 90°C for 8 hours to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2;

[0252] S4, loaded flame retardant:

[0253] 2 g of dimethyl methylphosphonate was added to 100 mL of deionized water, stirred at 90° C. for 15 min, 1.5 g of MWCNTs@Al2O3@SiO2 prepared in step S4 was added under stirring, ultrasonically dispersed at 90° C. for 60 min, then naturally cooled to room temperature, allowed to stand for 12 h, centrifuged and filtered, the solid product was washed with ethanol, and vacuum dried at 70° C. for 12 h to obtain a composite filler loaded with a flame retardant: DMMP-MWCNTs@Al2O3@SiO2;

[0254] S5, coating hydrophobic modified membrane:

[0255] S5-1, take 1g of DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, add it to 100mL of ethanol, ultrasonically disperse it for 30min, then add 1.2mL of 3-aminopropyltriethoxysilane, react at 60°C for 4h, centrifuge the product, add the solid product to 150mL of toluene, ultrasonically disperse it for 15min, and obtain a filler dispersion;

[0256] S5-2. Add 0.75g styrene, 0.3g hydroxy silicone oil and 0.15g azobisisobutyronitrile (AIBN) to the filler dispersion, flow nitrogen for 30 minutes with stirring, and react at 65°C for 1 hour; then add 1.25g styrene, 0.95g hydroxy silicone oil and 0.4g azobisisobutyronitrile (AIBN), raise the temperature to 70°C, and react for 3 hours. After the reaction, the product is centrifuged, and the solid product is washed with ethanol and deionized water in turn, and vacuum dried at 60°C for 12 hours to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

[0257] The surface paper layer, the corrugated paper core layer and the inner paper layer are prepared from the same raw materials, and are all prepared from the following components by weight:

[0258]

[0259] 4 parts of carboxymethyl cellulose

[0260] 250 parts of water.

[0261] The preparation method of the waterproof and flame-retardant high-performance composite corrugated paper comprises the following steps:

[0262] 1) adding lignin fiber, corn straw powder, oxidized starch and corn straw powder into water, stirring evenly and then crushing, passing through a 100-mesh sieve, then adding polyvinyl alcohol, polyacrylamide and carboxymethyl cellulose, beating at 200 rpm and 70° C. for 30 min, and then standing for 2 h to obtain pulp;

[0263] 2) Drying and shaping the pulp liquid to prepare a surface paper layer and a lining paper layer; Making the pulp liquid into corrugated base paper, and then corrugating and shaping it to obtain a corrugated paper core layer;

[0264] 3) adding the composite multi-effect enhancer to acetone, ultrasonically dispersing for 60 minutes, then adding bisphenol A epoxy resin, methyl silicone resin, tetraethylene pentamine, and chlorinated paraffin, stirring at 2000 rpm for 10 minutes, to obtain a waterproof and antistatic composite reinforced coating;

[0265] The composite multi-effect enhancer was added to toluene, and ultrasonically dispersed for 45 minutes, and then bisphenol F epoxy resin, bisphenol A epoxy resin, polyurethane acrylate, and hydrogenated terpene resin were added and stirred for 30 minutes, and finally 2-phenylimidazole and 2-ethylimidazole were added and stirred for 15 minutes to obtain a flame retardant adhesive;

[0266] 4) Apply flame retardant glue on the inner surface of the face paper layer and the outer surface of the inner paper layer respectively, then bond the inner surface of the face paper layer to the outer surface of the corrugated paper core layer, and bond the outer surface of the inner paper layer to the inner surface of the corrugated paper core layer, compact with a flattening roller, and dry at 75°C for 60 minutes;

[0267] The waterproof and antistatic composite reinforced coating is sprayed on the outer surface of the surface paper layer and the inner surface of the inner paper layer, respectively, with a spraying thickness of 0.6 mm. The coating is cured at room temperature for 6 hours and then at 80°C for 1.5 hours to form an outer waterproof and antistatic composite reinforced coating and an inner waterproof and antistatic reinforced composite coating, respectively, and finally a waterproof and flame-retardant high-performance composite corrugated paper is obtained.

[0268] Comparative Example 1

[0269] This example is basically the same as Example 1, except that the waterproof and antistatic composite reinforced coating of this example does not contain a composite multi-effect enhancer.

[0270] Comparative Example 2

[0271] This example is basically the same as Example 1, except that the raw materials for preparing the flame retardant rubber in this example do not contain a composite multi-effect enhancer.

[0272] Comparative Example 3

[0273] Antistatic remains unchanged, contact angle decreases by 3, flame retardancy decreases by 3, and the rest decrease slightly

[0274] This example is basically the same as Example 1, except that:

[0275] In this example, the composite multi-effect enhancer is prepared by the following steps:

[0276] S1, preparing acidified carbon nanotubes, the same as in Example 1;

[0277] S2, preparing porous silica microspheres, the same as in Example 1;

[0278] S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler:

[0279] S3-1, take 1g of porous silica microspheres and add them into an ethanol aqueous solution consisting of 80mL of deionized water and 120mL of ethanol, ultrasonically disperse for 30min, then add 0.375g of Al(NO3)3·9H2O, stir at 600rpm for 45min to obtain a microsphere dispersion;

[0280] S3-2, taking 0.8 g of acidified carbon nanotubes and adding them into 100 mL of deionized water, and ultrasonically dispersing them for 30 min to obtain a carbon nanotube dispersion;

[0281] S3-3. Add the carbon nanotube dispersion to the microsphere dispersion under stirring and stir for 60 minutes. Transfer the resulting mixture to a reactor and react at 200°C for 12 hours. After the reaction is completed, cool to room temperature and centrifuge to filter. Wash the solid product with deionized water and vacuum dry at 90°C for 8 hours to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2.

[0282] S4, loading flame retardant, the same as in Example 1;

[0283] S5, coating with a hydrophobic modified membrane, the same as in Example 1.

[0284] Comparative Example 4

[0285] This example is basically the same as Example 1, except that:

[0286] In this example, the composite multi-effect enhancer is prepared by the following steps:

[0287] S1, preparing porous silica microspheres, the same as step S2 of Example 1;

[0288] S2. Preparation of aluminum-doped porous silica composite filler:

[0289] 1 g of porous silica microspheres was added to an ethanol aqueous solution consisting of 80 mL of deionized water and 120 mL of ethanol, and ultrasonically dispersed for 30 min. Then, 1.125 g of Al(NO3)3·9H2O was added and stirred at 600 rpm for 45 min. The obtained microsphere dispersion was transferred to a reactor and reacted at 200°C for 12 h. After the reaction was completed, it was cooled to room temperature and centrifuged. The solid product was washed with deionized water and vacuum dried at 90°C for 8 h to obtain an aluminum-doped porous silica composite filler: Al2O3@SiO2.

[0290] S3, loaded flame retardant:

[0291] 2 g of dimethyl methylphosphonate was added to 100 mL of deionized water, stirred at 90° C. for 15 min, 1.5 g of Al2O3@SiO2 prepared in step S3 was added under stirring, ultrasonically dispersed at 90° C. for 60 min, then naturally cooled to room temperature, allowed to stand for 12 h, centrifuged and filtered, the solid product was washed with ethanol, and vacuum dried at 70° C. for 12 h to obtain a composite filler loaded with a flame retardant: DMMP-Al2O3@SiO2;

[0292] S4, coating hydrophobic modified membrane:

[0293] S4-1, take 1g of DMMP-Al2O3@SiO2 prepared in step S3, add it to 100mL of ethanol, ultrasonically disperse it for 30min, then add 1.2mL of 3-aminopropyltriethoxysilane, react at 60°C for 4h, centrifuge the product, add the solid product to 150mL of toluene, ultrasonically disperse it for 15min, and obtain a filler dispersion;

[0294] S4-2. Add 0.75g styrene, 0.3g hydroxy silicone oil and 0.15g azobisisobutyronitrile (AIBN) to the filler dispersion, flow nitrogen for 30 minutes with stirring, and react at 65°C for 1 hour; then add 1.25g styrene, 0.95g hydroxy silicone oil and 0.4g azobisisobutyronitrile (AIBN), raise the temperature to 70°C, and react for 3 hours. After the reaction, the product is centrifuged, and the solid product is washed with ethanol and deionized water in turn, and vacuum dried at 60°C for 12 hours to obtain a composite multi-effect enhancer.

[0295] Comparative Example 5

[0296] In this example, the composite filler loaded with flame retardant prepared in Example 1 is used as the composite multi-effect reinforcing agent.

[0297] Comparative Example 6

[0298] This example is basically the same as Example 1, except that:

[0299] In this example, the composite multi-effect enhancer is prepared by the following steps:

[0300] S1, preparing acidified carbon nanotubes, the same as in Example 1;

[0301] S2, preparing porous silica microspheres, the same as in Example 1;

[0302] S3, preparing aluminum-doped porous silica grafted carbon nanotube composite filler, the same as in Example 1;

[0303] S4, loading flame retardant, the same as in Example 1;

[0304] S5, coating hydrophobic modified membrane:

[0305] S5-1, take 1g of DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, add it to 100mL of ethanol, ultrasonically disperse it for 30min, then add 1.2mL of 3-aminopropyltriethoxysilane, react at 60°C for 4h, centrifuge the product, add the solid product to 150mL of toluene, ultrasonically disperse it for 15min, and obtain a filler dispersion;

[0306] S5-2. Add 0.75g styrene and 0.15g azobisisobutyronitrile (AIBN) to the filler dispersion, flow nitrogen for 30 minutes with stirring, and react at 65°C for 1 hour; then add 1.25g styrene, 0.95g hydroxy silicone oil, and 0.4g azobisisobutyronitrile (AIBN), raise the temperature to 70°C, and react for 3 hours. After the reaction is completed, the product is centrifuged, and the solid product is washed with ethanol and deionized water in turn, and vacuum dried at 60°C for 12 hours to obtain a composite multi-effect enhancer.

[0307] Performance Test:

[0308] 1. Sustained release performance

[0309] The sustained release performance of dimethyl methylphosphonate of the composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS prepared in Example 1 was tested, and the test method was as follows:

[0310] Take 1g of DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS prepared in Example 1 and add it to deionized water, dilute to 100mL, stir for 15min, and then stand at room temperature. Sampling (sampling volume is 0.5mL) is performed every other day to test the concentration of dimethyl methylphosphonate, and then deionized water is added to 100mL; the release percentage of dimethyl methylphosphonate at different times is calculated according to the following formula: t :

[0311]

[0312] Wherein, V = 100 mL, Q0 represents the initial loading amount of dimethyl methylphosphonate in DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS (the method for obtaining the dimethyl methylphosphonate is as follows: the concentration of dimethyl methylphosphonate in the deionized water after immersion in step S4 is measured, and then its content Q1 is calculated, Q0 = Q1-Q2, Q2 is the amount of dimethyl methylphosphonate added in step S4, i.e., Q2 = 2 g);

[0313] The test was continued for 200 h, and a release curve was plotted with the cumulative value of the released percentage (cumulative released percentage) as the ordinate and the release time as the abscissa.

[0314] Among them, the concentration of dimethyl methylphosphonate is detected by gas chromatography, referring to the standard "HG / T5714-2020 Dimethyl Methylphosphonate for Industrial Use".

[0315] Reference Figure 1 As shown in the test results, the composite multi-effect enhancer can achieve the long-term sustained release of dimethyl methylphosphonate.

[0316] 2. Contact angle: Measure the surface contact angle of the coating on the outer surface of each sample's surface paper layer according to standard ASTM D7334-08. Test each sample 5 times and take the average value as the measurement result. Since the coating material of the outer surface of the surface paper layer and the inner surface of the inner paper layer is the same, only the contact angle of one of the coatings is measured.

[0317] The influence of aluminum doping amount on contact angle is explored:

[0318] According to the method of Example 1, the amount of Al(NO3)3·9H2O added in step S3 of preparing the composite multi-effect enhancer was changed (0.1875 g, 0.375 g, 0.75 g, 1.125 g, and 1.5 g, respectively), to prepare the corresponding waterproof and flame-retardant high-performance composite corrugated paper, and then test the surface contact angle of the coating on the outer surface of the surface paper layer to obtain the surface contact angle of the coating obtained by different aluminum doping amounts. The test results are as follows: Figure 2 As shown, it can be seen that within a certain range, with the increase of aluminum doping amount, the contact angle gradually increases, which is mainly attributed to the formation of a slightly convex spherical structure of Al2O3 on the surface of the porous silica microspheres, which can increase the surface roughness and thus improve the hydrophobicity; when the aluminum doping amount reaches 1.125g, the contact angle is no longer significantly changed when the doping amount is increased. Considering comprehensively, the preferred Al(NO3)3·9H2O addition amount in the present invention is 1.125g.

[0319] 3. Flame retardant performance: Limiting oxygen index (LOI) test is carried out in accordance with the standard "GB / T5454-1997";

[0320] 4. Antistatic performance: Measure the surface resistance of the coating on the outer surface of the face paper layer of each sample, referring to the standard GB / T1410-2006 solid insulating material volume resistivity and surface resistivity test method; because the coating materials of the outer surface of the face paper layer and the inner surface of the inner paper layer are the same, only the surface resistance of one of the coatings is measured.

[0321] 4. Burst strength: tested according to the standard "GB / T6544-2008";

[0322] 5. Edge compression strength: tested in accordance with the standard "GB / T6544-2008";

[0323] 6. Bond strength: tested according to the standard "GB / T6548-2011";

[0324] The test results are shown in Table 1 and Figure 3-8 As shown:

[0325] Table 1

[0326]

[0327]

[0328] It can be seen from the test results in Table 1 that the surface of the corrugated paper prepared in Examples 1-4 has excellent hydrophobicity and antistatic properties, and both the flame retardant property and the overall strength are excellent; the composite multi-effect enhancer is not added to the waterproof and antistatic composite reinforced coating of Comparative Example 1, resulting in a significant decrease in the hydrophobicity and antistatic properties, and the flame retardant property is also greatly decreased; the composite multi-effect enhancer is not added to the flame retardant glue of Comparative Example 2, resulting in a significant decrease in the overall flame retardant property, and the mechanical strength is also greatly decreased; the doped Al in Comparative Example 3 is reduced, resulting in a decrease in the contact angle; the absence of the addition of acidified carbon nanotubes in Comparative Example 4 leads to a decrease in the antistatic property and the mechanical strength; the hydrophobic modified film is not coated in Comparative Example 5, and the overall performance is reduced; hydroxy silicone oil is not added to the coating film in Comparative Example 6, and the hydrophobic property is reduced.

[0329] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. A waterproof and flame-retardant high-performance composite corrugated paper, characterized in that: It includes an outer waterproof and antistatic composite enhanced coating, a surface paper layer, a corrugated paper core layer, a lining paper layer, and an inner waterproof and antistatic enhanced composite coating which are arranged in sequence from the outside to the inside; The outer waterproof antistatic composite enhanced coating and the inner waterproof antistatic enhanced composite coating are both obtained by coating a waterproof antistatic composite enhanced coating and then curing it. The waterproof antistatic composite enhanced coating includes the following raw material components in parts by weight: 55-75 parts of bisphenol A epoxy resin, 10-24 parts of methyl silicone resin, 2-6.5 parts of tetraethylene pentamine, 3-12 parts of chlorinated paraffin, 3-18 parts of composite multi-effect enhancer, and 40-70 parts of acetone; The composite multi-effect enhancer is prepared by the following steps: S1, preparing acidified carbon nanotubes; S2, preparing porous silica microspheres; S3, using acidified carbon nanotubes and porous silica microspheres to prepare aluminum-doped porous silica grafted carbon nanotube composite filler: S3-1, taking porous silica microspheres and adding them into an ethanol aqueous solution composed of deionized water and ethanol, ultrasonically dispersing them, then adding Al(NO3)3·9H2O and stirring to obtain a microsphere dispersion; S3-2, adding the acidified carbon nanotubes into deionized water, and dispersing by ultrasonication to obtain a carbon nanotube dispersion; S3-3, under stirring, adding the carbon nanotube dispersion to the microsphere dispersion, stirring, transferring the obtained mixture to a reactor, reacting under heating, cooling to room temperature after the reaction, centrifuging, filtering, washing the solid product, and vacuum drying to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2; S4, loading a flame retardant on MWCNTs@Al2O3@SiO2 to obtain a composite filler loaded with a flame retardant; S5. Coating a hydrophobic modified film on the composite filler loaded with a flame retardant to obtain the composite multi-effect enhancer, wherein the hydrophobic modified film is a polysiloxane-modified polystyrene composite film.

2. The waterproof and flame-retardant high-performance composite corrugated paper according to claim 1, characterized in that: Step S1 specifically comprises: adding multi-walled carbon nanotubes to a mixed acid solution consisting of 95 wt % concentrated sulfuric acid and 65 wt % concentrated nitric acid, ultrasonicating, then stirring and refluxing under heating, cooling to room temperature and filtering, washing with deionized water until neutral, and vacuum drying to obtain acidified carbon nanotubes; Step S2 is specifically as follows: S2-1, adding hexadecyltrimethylammonium bromide and 1,3,5-trimethylbenzene to an alcohol solution consisting of isopropanol and deionized water, ultrasonically dispersing, adding ammonia water, and ultrasonically dispersing; S2-2, adding ethyl orthosilicate to the mixture obtained in step S2-1 under stirring, reacting under heating, filtering after the reaction, washing the solid product, and calcining under air atmosphere to obtain porous silica microspheres.

3. The waterproof and flame-retardant high-performance composite corrugated paper according to claim 1, characterized in that: Step S4 is specifically as follows: add dimethyl methylphosphonate to deionized water, stir, add MWCNTs@Al2O3@SiO2 prepared in step S3 under stirring, ultrasonically disperse, then naturally cool to room temperature, stand, centrifuge and filter, wash the solid product with ethanol, and vacuum dry to obtain a composite filler loaded with flame retardant: DMMP-MWCNTs@Al2O3@SiO2.

4. The waterproof and flame-retardant high-performance composite corrugated paper according to claim 1, characterized in that: Step S5 is specifically as follows: S5-1, taking the DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, adding it to ethanol, ultrasonically dispersing it, then adding 3-aminopropyltriethoxysilane, reacting under heating, centrifuging the product, adding the solid product to toluene, ultrasonically dispersing it, and obtaining a filler dispersion; S5-2. Add styrene, hydroxy silicone oil and azobisisobutyronitrile to the filler dispersion, pass nitrogen under stirring, and heat to react; then add styrene, hydroxy silicone oil and azobisisobutyronitrile, and heat to react. After the reaction is completed, the product is centrifuged, the solid product is washed, and vacuum dried to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

5. The waterproof and flame-retardant high-performance composite corrugated paper according to claim 1, characterized in that: The composite multi-effect enhancer is prepared by the following steps: S1. Preparation of acidified carbon nanotubes: 2 g of multi-walled carbon nanotubes were added to 200 mL of a mixed acid solution consisting of 95 wt% concentrated sulfuric acid and 65 wt% concentrated nitric acid in a volume ratio of 3:1, ultrasonicated for 2 h, then stirred and refluxed at 80 ° C for 12 h, cooled to room temperature and filtered, washed with deionized water until neutral, and vacuum dried at 90 ° C for 8 h to obtain acidified carbon nanotubes; S2. Preparation of porous silica microspheres: S2-1, take 2g of hexadecyltrimethylammonium bromide and 0.85g of 1,3,5-trimethylbenzene, add them into 360mL of an alcohol solution composed of isopropanol and deionized water in a volume ratio of 1:1, ultrasonically disperse for 5min, add 5mL of 25% ammonia water, and ultrasonically disperse for 15min; S2-2, adding 12.5 mL of tetraethyl orthosilicate to the mixture obtained in step S2-1 under stirring, reacting at 55° C. for 12 h, filtering after the reaction, washing the solid product with ethanol and deionized water in sequence, and calcining at 550° C. in air atmosphere for 5 h to obtain porous silica microspheres; S3. Preparation of aluminum-doped porous silica grafted carbon nanotube composite filler: S3-1, take 1g of porous silica microspheres and add them into an ethanol aqueous solution consisting of 80mL of deionized water and 120mL of ethanol, ultrasonically disperse for 30min, then add 1.125g of Al(NO3)3·9H2O, stir at 600rpm for 45min to obtain a microsphere dispersion; S3-2, taking 0.8 g of acidified carbon nanotubes and adding them into 100 mL of deionized water, and ultrasonically dispersing them for 30 min to obtain a carbon nanotube dispersion; S3-3, under stirring, adding the carbon nanotube dispersion to the microsphere dispersion, stirring for 60 minutes, transferring the obtained mixture to a reactor, reacting at 200°C for 12 hours, cooling to room temperature after the reaction, centrifuging and filtering, washing the solid product with deionized water, and vacuum drying at 90°C for 8 hours to obtain aluminum-doped porous silica grafted carbon nanotube composite filler: MWCNTs@Al2O3@SiO2; S4, loaded flame retardant: 2 g of dimethyl methylphosphonate was added to 100 mL of deionized water, stirred at 90° C. for 15 min, 1.5 g of MWCNTs@Al2O3@SiO2 prepared in step S4 was added under stirring, ultrasonically dispersed at 90° C. for 60 min, then naturally cooled to room temperature, allowed to stand for 12 h, centrifuged and filtered, the solid product was washed with ethanol, and vacuum dried at 70° C. for 12 h to obtain a composite filler loaded with a flame retardant: DMMP-MWCNTs@Al2O3@SiO2; S5, coating hydrophobic modified membrane: S5-1, take 1g of DMMP-MWCNTs@Al2O3@SiO2 prepared in step S4, add it to 100mL of ethanol, and disperse it by ultrasonication for 30min, then add 1.2mL of 3-aminopropyltriethoxysilane, react at 60°C for 4h, separate the product by centrifugation, add the solid product to 150mL of toluene, and disperse it by ultrasonication for 15min to obtain a filler dispersion; S5-2. Add 0.75g styrene, 0.3g hydroxy silicone oil and 0.15g azobisisobutyronitrile to the filler dispersion, flow nitrogen for 30 minutes with stirring, and react at 65°C for 1 hour; then add 1.25g styrene, 0.95g hydroxy silicone oil and 0.4g azobisisobutyronitrile, raise the temperature to 70°C and react for 3 hours. After the reaction, the product is centrifuged and the solid product is washed with ethanol and deionized water in turn, and vacuum dried at 60°C for 12 hours to obtain a composite multi-effect enhancer: DMMP-MWCNTs@Al2O3@SiO2-PS-PDMS.

6. The waterproof and flame-retardant high-performance composite corrugated paper according to claim 1, characterized in that: in, The surface paper layer and the corrugated paper core layer, as well as the corrugated paper core layer and the inner paper layer are bonded by flame retardant adhesive. The raw materials for preparing the flame retardant adhesive include, by weight: 12-28 parts of bisphenol F epoxy resin, 15-40 parts of bisphenol A epoxy resin, 15-48 parts of polyurethane acrylate, 3-15 parts of hydrogenated terpene resin, 0.2-1 parts of 2-phenylimidazole, 0.3-1 parts of 2-ethylimidazole, 5-30 parts of composite multi-effect enhancer, and 20-70 parts of toluene.

7. The waterproof and flame-retardant high-performance composite corrugated paper according to claim 1, characterized in that: The surface paper layer, the corrugated paper core layer and the inner paper layer are prepared from the same raw materials, and are all prepared from the following components by weight: 40-65 parts of lignin fiber; 5-27 parts corn starch; 5-15 parts of oxidized starch; 6-48 parts corn stalk powder; 3-12 parts of polyvinyl alcohol; 2-16 parts of polyacrylamide; Carboxymethyl cellulose 2- 8 parts; 180-500 parts of water.

8. A method for preparing the waterproof, flame-retardant, high-performance composite corrugated paper according to any one of claims 1 to 7, characterized in that: The following steps are involved: 1) Add lignin fiber, corn straw powder, oxidized starch and corn straw powder into water, stir evenly and then crush, pass through a 50-100 mesh sieve, then add polyvinyl alcohol, polyacrylamide and carboxymethyl cellulose, beat at 100-350rpm and 60-80℃ for 15-60min, then let stand for 1-3h to obtain pulp liquid; 2) Drying and shaping the pulp liquid to prepare the surface paper layer and the inner paper layer; Making the pulp liquid into corrugated base paper, and then corrugating and shaping to obtain the corrugated paper core layer; 3) Add the composite multi-effect enhancer to acetone, ultrasonically disperse for 15-90 minutes, then add bisphenol A epoxy resin, methyl silicone resin, tetraethylene pentamine, and chlorinated paraffin, and stir at a speed of 1000-4000 rpm for 5-20 minutes to obtain a waterproof and antistatic composite reinforced coating; The composite multi-effect enhancer is added to toluene, ultrasonically dispersed for 30-60 minutes, then bisphenol F epoxy resin, bisphenol A epoxy resin, polyurethane acrylate, hydrogenated terpene resin are added, stirred for 15-45 minutes, and finally 2-phenylimidazole and 2-ethylimidazole are added, stirred for 5-30 minutes to obtain a flame retardant adhesive; 4) Apply flame retardant glue on the inner surface of the face paper layer and the outer surface of the inner paper layer respectively, then bond the inner surface of the face paper layer to the outer surface of the corrugated paper core layer, and bond the outer surface of the inner paper layer to the inner surface of the corrugated paper core layer, compact with a flattening roller, and dry at 60-85℃ for 15-120min; A waterproof and antistatic composite reinforced coating is sprayed on the outer surface of the surface paper layer and the inner surface of the inner paper layer, respectively, with a spraying thickness of 0.2-1 mm, and cured at room temperature for 4-8 hours, and then cured at 70-85°C for 1-3 hours to form an outer waterproof and antistatic composite reinforced coating and an inner waterproof and antistatic reinforced composite coating, respectively, to finally obtain the waterproof, flame-retardant, high-performance composite corrugated paper.

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