CN111363311A - Graphene-anhydride curing agent modified waterborne epoxy resin material and preparation method thereof - Google Patents
Graphene-anhydride curing agent modified waterborne epoxy resin material and preparation method thereof Download PDFInfo
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Abstract
The invention relates to the technical field of epoxy resin, and discloses a graphene-anhydride curing agent modified waterborne epoxy resin material which comprises the following formula raw materials and components: functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, an initiator and epoxy resin. According to the graphene-anhydride curing agent modified waterborne epoxy resin material, high-vinyl-content functionalized graphene is subjected to free radical polymerization with waterborne methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride to obtain graphene grafted succinic anhydride-waterborne acrylate resin serving as an anhydride curing agent, the epoxy resin is endowed with good hydrophilicity by the very-hydrophilic waterborne acrylate, and in the thermosetting and crosslinking process of the epoxy resin, the graphene is introduced into an epoxy resin matrix through covalent bond modification, so that the compatibility of the graphene and the epoxy resin is improved, and the impact strength and the tensile strength of the epoxy resin are enhanced.
Description
Technical Field
The invention relates to the technical field of epoxy resin, in particular to a graphene-anhydride curing agent modified waterborne epoxy resin material and a preparation method thereof.
Background
The water-based epoxy resin can be divided into anionic epoxy resin and cationic epoxy resin, can be prepared by a mechanical method, a chemical modification method, a phase inversion method and a curing agent emulsification method, has the advantages of excellent corrosion resistance, strong adaptability, no application of organic solvents, good environmental protection performance, good operability and the like, and has important application in the fields of automobile coating, medical appliances, electronic and electric products, light industrial products and the like.
In order to enhance the mechanical properties, the service performance and the like of the waterborne epoxy resin, the modification can be implemented from the aspects of curing agent modification, reactive diluent modification, filler modification, modified epoxy resin and the like, the graphene serving as a two-dimensional carbon nano material has excellent optical properties, electrical properties and mechanical properties, and can be used as a filler to be filled into organic polymers such as epoxy resin, polyurethane, acrylic resin and the like to enhance the comprehensive properties of the material, but the graphene has a large specific surface area, the van der waals force among graphene nanoparticles is strong, the compatibility of the graphene and the epoxy resin is poor, and the graphene is easy to agglomerate and agglomerate in the epoxy resin matrix, so that the mechanical properties of the tensile strength and the wear resistance of the material are seriously affected.
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a graphene-anhydride curing agent modified waterborne epoxy resin material and a preparation method thereof, which solve the problem that the traditional epoxy resin does not have waterborne property and simultaneously solve the problem that the compatibility of graphene nanoparticles and epoxy resin is poor.
(II) technical scheme
In order to achieve the purpose, the invention provides the following technical scheme: a graphene-anhydride curing agent modified waterborne epoxy resin material comprises the following raw materials and components: the modified graphene material comprises functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, an initiator and epoxy resin in a mass ratio of 0.5-5:1-2:8-15:1-3:35-45:0.3-0.5:100
Preferably, the initiator is dibenzoyl peroxide.
Preferably, the preparation method of the graphene-anhydride curing agent modified waterborne epoxy resin material comprises the following steps:
(1) adding graphene oxide and a distilled water solvent into a reaction bottle, after uniform ultrasonic dispersion, transferring the solution into a hydrothermal reaction kettle, heating to 190 ℃ for heat preservation treatment, carrying out freeze drying on the solution to remove the solvent, placing the obtained graphene aerogel into a potassium hydroxide solution, standing for 12-18h after uniform ultrasonic dispersion, carrying out vacuum drying on the solution to remove the solvent, placing the solid mixed product into an atmosphere furnace, heating to 800 ℃ in an argon atmosphere, carrying out heat preservation treatment for 1-2h, washing the calcined product with dilute hydrochloric acid and distilled water until the calcined product is neutral, and thus obtaining the three-dimensional porous graphene.
(2) Adding a distilled water solvent and three-dimensional porous graphene into a reaction bottle, adding dilute hydrochloric acid to adjust the pH of the solution to 2-3 after uniform ultrasonic dispersion, adding ferrous chloride at 30-40 ℃, dropwise adding a hydrogen peroxide aqueous solution by using a trace sample injection device after uniform stirring, stirring at a constant speed for reaction for 1-2h, centrifugally separating, washing and drying by using distilled water, and thus obtaining the hydroxyl-enriched graphene.
(3) Adding a toluene solvent and hydroxyl-rich graphene into a reaction bottle, uniformly dispersing by ultrasonic, adding a vinyl silane coupling agent, reacting for 5-10h at 100-120 ℃ under uniform stirring, centrifugally separating, washing and drying by using ethanol, and thus obtaining the functionalized graphene with high vinyl content.
(4) Adding a xylene solvent, methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride into a reaction bottle, uniformly stirring to prepare an acrylate mixed solution, preparing a xylene solution of functionalized graphene, uniformly dispersing by using ultrasonic waves, adding 2/3 volumes of the acrylate mixed solution, adding an initiator dibenzoyl peroxide, heating to 80-90 ℃ in a nitrogen atmosphere, uniformly stirring for reaction for 30-60min, dropwise adding the rest 1/3 volumes of the acrylate mixed solution by using a micro-sampling device, and uniformly stirring for reaction for 4-6h to obtain the graphene grafted succinic anhydride-water-based acrylate resin.
(5) Adding epoxy resin and graphene grafted succinic anhydride-waterborne acrylate resin into a distilled water solvent, uniformly stirring, pouring the materials into a film forming mold, and performing thermosetting film forming to prepare the graphene-anhydride curing agent modified waterborne epoxy resin material.
Preferably, the mass ratio of the graphene aerogel and the potassium hydroxide in the step (1) is 1: 3-6.
Preferably, the mass ratio of the three-dimensional porous graphene, the ferrous chloride and the hydrogen peroxide in the step (2) is 1:15-25: 80-120.
Preferably, the micro-sampling device in step (2) comprises a base, a reaction bottle arranged on the upper surface of the base, a support rod fixedly connected with the upper part of the base, a regulating valve movably connected with the support rod, a movable rod movably connected with the regulating valve, a movable clamping plate fixedly connected with the movable rod, a clamping groove arranged on the surface of the support rod, a clamping block movably connected with the clamping groove, a regulating rod fixedly connected with the clamping block, and a micro-sampler fixedly connected with the regulating rod and the regulating rod.
Preferably, the vinylsilane coupling agent in the step (3) is any one of vinyltriethoxysilane, vinyltrimethoxysilane, methylvinyldiethoxysilane and methylvinyldimethoxysilane, and the mass ratio of the vinylsilane coupling agent to the hydroxyl-enriched graphene is 1-4: 1.
(III) advantageous technical effects
Compared with the prior art, the invention has the following beneficial technical effects:
according to the graphene-anhydride curing agent modified waterborne epoxy resin material, a graphene hydrogel prepared by a high-pressure hydrothermal method generates a large number of pore structures under the etching action of potassium hydroxide to form three-dimensional porous graphene with a huge specific surface area, hydrogen peroxide generates hydroxyl radicals under the action of ferrous chloride to be bonded with carbon atoms on the surface of the three-dimensional porous graphene to prepare hydroxylated graphene with very high hydroxyl groups, and a large number of hydroxyl groups easily react with a vinyl silane coupling agent to obtain the functionalized graphene with high vinyl content.
The graphene-anhydride curing agent modified waterborne epoxy resin material is characterized in that under the action of dibenzoyl peroxide, rich vinyl groups of functionalized graphene are subjected to free radical polymerization with waterborne methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride to obtain graphene grafted succinic anhydride-waterborne acrylate resin, succinic anhydride groups are covalently grafted to the surfaces of graphene nanoparticles, the graphene grafted succinic anhydride-waterborne acrylate resin containing rich anhydride groups is used as an anhydride curing agent, the epoxy resin is endowed with good hydrophilicity by the waterborne acrylate with strong hydrophilicity, meanwhile, the anhydride groups and epoxy groups in the epoxy resin are subjected to ring-opening thermosetting crosslinking reaction, graphene and waterborne acrylate molecular chains are introduced into an epoxy resin matrix through covalent bond modification, so that the compatibility of the graphene nanoparticles and the epoxy resin is remarkably improved, the graphene with uniform dispersion enhances the mechanical properties of the epoxy resin, such as impact strength, tensile strength and the like.
Drawings
FIG. 1 is a schematic view of a microsyringe;
FIG. 2 is a schematic view of an adjustment lever and a travel bar adjustment;
fig. 3 is a Scanning Electron Microscope (SEM) image of functionalized graphene.
1-a base; 2-reaction flask; 3-supporting rods; 4-adjusting the valve; 5-moving the rod; 6-clamping plate; 7-a clamping groove; 8-a fixture block; 9-adjusting the rod; 10-microsampler.
Detailed Description
To achieve the above object, the present invention provides the following embodiments and examples: a graphene-anhydride curing agent modified waterborne epoxy resin material comprises the following raw materials and components: functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, initiator dibenzoyl peroxide and epoxy resin in a mass ratio of 0.5-5:1-2:8-15:1-3:35-45:0.3-0.5:100
The preparation method of the graphene-anhydride curing agent modified waterborne epoxy resin material comprises the following steps:
(1) adding graphene oxide and a distilled water solvent into a reaction bottle, after uniform ultrasonic dispersion, transferring the solution into a hydrothermal reaction kettle, heating to 190 ℃ for heat preservation treatment for 6-10h, freeze-drying the solution to remove the solvent, placing the obtained graphene aerogel into the distilled water solvent, adding potassium hydroxide, wherein the mass ratio of the potassium hydroxide to the graphene aerogel is 3-6:1, standing for 12-18h after uniform ultrasonic dispersion, vacuum-drying the solution to remove the solvent, placing the solid mixed product into an atmosphere furnace, heating to 800 ℃ in an argon atmosphere, heat preservation treatment for 1-2h, washing the calcined product with dilute hydrochloric acid and distilled water until the calcined product is neutral, and thus obtaining the three-dimensional porous graphene.
(2) Adding distilled water solvent and three-dimensional porous graphene into a reaction bottle, adding dilute hydrochloric acid to adjust the pH value of the solution to 2-3 after uniform ultrasonic dispersion, adding ferrous chloride at 30-40 ℃, dropwise adding hydrogen peroxide solution by using a micro-sampling device after uniform stirring, wherein the micro-sampling device comprises a base, a reaction bottle is arranged on the upper surface of the base, a supporting rod is fixedly connected above the base, a regulating valve is movably connected with the supporting rod, the regulating valve is movably connected with a moving rod, the moving rod is fixedly connected with a clamping plate, the surface of the supporting rod is provided with a clamping groove, the clamping groove is movably connected with a clamping block, the clamping block is fixedly connected with a regulating rod, and a micro-sampler is fixedly connected between the regulating rods, wherein the mass ratio of the three-dimensional porous graphene, the ferrous chloride and the hydrogen peroxide is 1, and centrifugally separating, washing and drying by using distilled water to prepare the hydroxyl-enriched graphene.
(3) Adding a toluene solvent and hydroxyl-enriched graphene into a reaction bottle, ultrasonically dispersing uniformly, adding a vinyl silane coupling agent which is any one of vinyl triethoxysilane, vinyl trimethoxy silane, methyl vinyl diethoxy silane and methyl vinyl dimethoxy silane in a mass ratio of 1-4:1 to the hydroxyl-enriched graphene, stirring at a constant speed at 100-120 ℃ for reaction for 5-10h, centrifugally separating, washing and drying by using ethanol, and preparing the high-vinyl-content functionalized graphene.
(4) Adding a xylene solvent, methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride into a reaction bottle, uniformly stirring to prepare an acrylate mixed solution, preparing a xylene solution of functionalized graphene, uniformly dispersing by using ultrasonic waves, adding 2/3 volumes of the acrylate mixed solution, adding an initiator dibenzoyl peroxide, heating to 80-90 ℃ in a nitrogen atmosphere, uniformly stirring for reaction for 30-60min, dropwise adding the rest 1/3 volumes of the acrylate mixed solution by using a micro-sampling device, and uniformly stirring for reaction for 4-6h to obtain the graphene grafted succinic anhydride-water-based acrylate resin.
(5) Adding epoxy resin and graphene grafted succinic anhydride-waterborne acrylate resin into a distilled water solvent, uniformly stirring, pouring the materials into a film forming mold, and performing thermosetting film forming to prepare the graphene-anhydride curing agent modified waterborne epoxy resin material.
Example 1
(1) Adding graphene oxide and a distilled water solvent into a reaction bottle, after uniform ultrasonic dispersion, transferring the solution into a hydrothermal reaction kettle, heating to 170 ℃, carrying out heat preservation treatment for 6 hours, freeze-drying the solution to remove the solvent, placing the obtained graphene aerogel into the distilled water solvent, adding potassium hydroxide, wherein the mass ratio of the potassium hydroxide to the graphene aerogel is 3:1, standing for 12 hours after uniform ultrasonic dispersion, carrying out vacuum drying on the solution to remove the solvent, placing a solid mixed product into an atmosphere furnace, heating to 700 ℃ in an argon atmosphere, carrying out heat preservation treatment for 1 hour, washing the calcined product with dilute hydrochloric acid and distilled water until the calcined product is neutral, and thus obtaining the three-dimensional porous graphene.
(2) Adding a distilled water solvent and three-dimensional porous graphene into a reaction bottle, adding dilute hydrochloric acid to adjust the pH value of the solution to 3 after uniform ultrasonic dispersion, ferrous chloride is added at the temperature of 30 ℃, after being uniformly stirred, a micro-sampling device is used for dropwise adding hydrogen peroxide water solution, the micro-sampling device comprises a base, a reaction bottle is arranged on the upper surface of the base, a supporting rod is fixedly connected above the base, the supporting rod is movably connected with an adjusting valve, the adjusting valve is movably connected with a movable rod, the movable rod is fixedly connected with a clamping plate, a clamping groove is arranged on the surface of the supporting rod, the clamping groove is movably connected with a clamping block, the clamping block is fixedly connected with an adjusting rod, and, the mass ratio of the three-dimensional porous graphene to the ferrous chloride to the hydrogen peroxide is 1:15:80, the three-dimensional porous graphene and the ferrous chloride are stirred at a constant speed to react for 1 hour, and the three-dimensional porous graphene is centrifugally separated, washed and dried by using distilled water to prepare the hydroxyl-enriched graphene.
(3) Adding a toluene solvent and hydroxyl-enriched graphene into a reaction bottle, ultrasonically dispersing uniformly, adding a vinyl silane coupling agent which is any one of vinyl triethoxysilane, vinyl trimethoxy silane, methyl vinyl diethoxy silane and methyl vinyl dimethoxy silane in a mass ratio of 1:1 with the hydroxyl-enriched graphene, stirring at a constant speed at 100 ℃ for reaction for 5 hours, centrifugally separating, washing and drying by using ethanol, and preparing the high-vinyl-content functionalized graphene.
(4) Adding a xylene solvent, methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride into a reaction bottle, uniformly stirring to prepare an acrylate mixed solution, preparing a xylene solution of functionalized graphene, uniformly dispersing by using ultrasonic waves, adding 2/3 volumes of the acrylate mixed solution, adding an initiator dibenzoyl peroxide, heating to 80 ℃ in a nitrogen atmosphere, uniformly stirring for reaction for 30min, dropwise adding the rest 1/3 volumes of the acrylate mixed solution by using a micro-sampling device, and uniformly stirring for reaction for 4h to obtain the graphene grafted succinic anhydride-water-based acrylate resin.
(5) Adding epoxy resin and graphene grafted succinic anhydride-waterborne acrylate resin into a distilled water solvent, wherein the mass ratio of functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, initiator dibenzoyl peroxide to epoxy resin is 0.5:1:8:1:35:0.3:100, uniformly stirring, pouring the materials into a film forming mold, and performing thermosetting film forming to prepare the graphene-anhydride curing agent modified waterborne epoxy resin material 1.
Example 2
(1) Adding graphene oxide and a distilled water solvent into a reaction bottle, after uniform ultrasonic dispersion, transferring the solution into a hydrothermal reaction kettle, heating to 190 ℃, carrying out heat preservation treatment for 10 hours, freeze-drying the solution to remove the solvent, placing the obtained graphene aerogel into the distilled water solvent, adding potassium hydroxide, wherein the mass ratio of the potassium hydroxide to the graphene aerogel is 4:1, standing for 12 hours after uniform ultrasonic dispersion, carrying out vacuum drying on the solution to remove the solvent, placing a solid mixed product into an atmosphere furnace, heating to 800 ℃ in an argon atmosphere, carrying out heat preservation treatment for 2 hours, washing the calcined product with dilute hydrochloric acid and distilled water until the calcined product is neutral, and thus obtaining the three-dimensional porous graphene.
(2) Adding a distilled water solvent and three-dimensional porous graphene into a reaction bottle, adding dilute hydrochloric acid to adjust the pH value of the solution to 3 after uniform ultrasonic dispersion, ferrous chloride is added at the temperature of 30 ℃, after being uniformly stirred, a micro-sampling device is used for dropwise adding hydrogen peroxide water solution, the micro-sampling device comprises a base, a reaction bottle is arranged on the upper surface of the base, a supporting rod is fixedly connected above the base, the supporting rod is movably connected with an adjusting valve, the adjusting valve is movably connected with a movable rod, the movable rod is fixedly connected with a clamping plate, a clamping groove is arranged on the surface of the supporting rod, the clamping groove is movably connected with a clamping block, the clamping block is fixedly connected with an adjusting rod, and, the mass ratio of the three-dimensional porous graphene to the ferrous chloride to the hydrogen peroxide is 1:18:90, the three-dimensional porous graphene and the ferrous chloride are stirred at a constant speed to react for 2 hours, and the three-dimensional porous graphene is centrifugally separated, washed and dried by using distilled water to prepare the hydroxyl-enriched graphene.
(3) Adding a toluene solvent and hydroxyl-enriched graphene into a reaction bottle, ultrasonically dispersing uniformly, adding a vinyl silane coupling agent which is any one of vinyl triethoxysilane, vinyl trimethoxy silane, methyl vinyl diethoxy silane and methyl vinyl dimethoxy silane in a mass ratio of 1.5:1 to the hydroxyl-enriched graphene, stirring at a constant speed at 100 ℃ for 10 hours, centrifugally separating, washing and drying by using ethanol, and preparing the high-vinyl-content functionalized graphene.
(4) Adding a xylene solvent, methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride into a reaction bottle, uniformly stirring to prepare an acrylate mixed solution, preparing a xylene solution of functionalized graphene, uniformly dispersing by using ultrasonic waves, adding 2/3 volumes of the acrylate mixed solution, adding an initiator dibenzoyl peroxide, heating to 90 ℃ in a nitrogen atmosphere, uniformly stirring for reaction for 60min, dropwise adding the rest 1/3 volumes of the acrylate mixed solution by using a micro-sampling device, and uniformly stirring for reaction for 4h to obtain the graphene grafted succinic anhydride-water-based acrylate resin.
(5) Adding epoxy resin and graphene grafted succinic anhydride-waterborne acrylate resin into a distilled water solvent, wherein the mass ratio of functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, initiator dibenzoyl peroxide to epoxy resin is 1:1.2:10:1.5:38:0.35:100, uniformly stirring, pouring the materials into a film forming mold, and performing thermosetting film forming to prepare the graphene-anhydride curing agent modified waterborne epoxy resin material 2.
Example 3
(1) Adding graphene oxide and a distilled water solvent into a reaction bottle, after uniform ultrasonic dispersion, transferring the solution into a hydrothermal reaction kettle, heating to 180 ℃, carrying out heat preservation treatment for 8 hours, freeze-drying the solution to remove the solvent, placing the obtained graphene aerogel into the distilled water solvent, adding potassium hydroxide, wherein the mass ratio of the potassium hydroxide to the graphene aerogel is 4.5:1, standing for 15 hours after uniform ultrasonic dispersion, carrying out vacuum drying on the solution to remove the solvent, placing the solid mixed product into an atmosphere furnace, heating to 750 ℃ in an argon atmosphere, carrying out heat preservation treatment for 1.5 hours, washing the calcined product with dilute hydrochloric acid and distilled water until the calcined product is neutral, and thus obtaining the three-dimensional porous graphene.
(2) Adding a distilled water solvent and three-dimensional porous graphene into a reaction bottle, adding dilute hydrochloric acid to adjust the pH value of the solution to 3 after uniform ultrasonic dispersion, ferrous chloride is added at the temperature of 35 ℃, after being uniformly stirred, a micro-sampling device is used for dropwise adding hydrogen peroxide water solution, the micro-sampling device comprises a base, a reaction bottle is arranged on the upper surface of the base, a supporting rod is fixedly connected above the base, the supporting rod is movably connected with an adjusting valve, the adjusting valve is movably connected with a movable rod, the movable rod is fixedly connected with a clamping plate, a clamping groove is arranged on the surface of the supporting rod, the clamping groove is movably connected with a clamping block, the clamping block is fixedly connected with an adjusting rod, and, the mass ratio of the three-dimensional porous graphene to the ferrous chloride to the hydrogen peroxide is 1:20:100, the three-dimensional porous graphene and the ferrous chloride are stirred at a constant speed and react for 1.5 hours, and distilled water is used for centrifugal separation, washing and drying to prepare the hydroxyl-enriched graphene.
(3) Adding a toluene solvent and hydroxyl-enriched graphene into a reaction bottle, ultrasonically dispersing uniformly, adding a vinyl silane coupling agent which is any one of vinyl triethoxysilane, vinyl trimethoxy silane, methyl vinyl diethoxy silane and methyl vinyl dimethoxy silane in a mass ratio of 2.5:1 to the hydroxyl-enriched graphene, stirring at a constant speed at 110 ℃ for reacting for 8 hours, centrifugally separating, washing and drying by using ethanol, and preparing the high-vinyl-content functionalized graphene.
(4) Adding a xylene solvent, methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride into a reaction bottle, uniformly stirring to prepare an acrylate mixed solution, preparing a xylene solution of functionalized graphene, uniformly dispersing by using ultrasonic waves, adding 2/3 volumes of the acrylate mixed solution, adding an initiator dibenzoyl peroxide, heating to 85 ℃ in a nitrogen atmosphere, uniformly stirring for reaction for 45min, dropwise adding the rest 1/3 volumes of the acrylate mixed solution by using a micro-sampling device, and uniformly stirring for reaction for 5h to obtain the graphene grafted succinic anhydride-water-based acrylate resin.
(5) Adding epoxy resin and graphene grafted succinic anhydride-waterborne acrylate resin into a distilled water solvent, wherein the mass ratio of functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, initiator dibenzoyl peroxide to epoxy resin is 3:1.5:12:2:40:0.4:100, uniformly stirring, pouring the materials into a film forming mold, and performing thermal curing to form a film to prepare the graphene-anhydride curing agent modified waterborne epoxy resin material 3.
Example 4
(1) Adding graphene oxide and a distilled water solvent into a reaction bottle, after uniform ultrasonic dispersion, transferring the solution into a hydrothermal reaction kettle, heating to 190 ℃, carrying out heat preservation treatment for 10 hours, freeze-drying the solution to remove the solvent, placing the obtained graphene aerogel into the distilled water solvent, adding potassium hydroxide, wherein the mass ratio of the potassium hydroxide to the graphene aerogel is 6:1, standing for 18 hours after uniform ultrasonic dispersion, carrying out vacuum drying on the solution to remove the solvent, placing the solid mixed product into an atmosphere furnace, heating to 700 ℃ in an argon atmosphere, carrying out heat preservation treatment for 2 hours, washing the calcined product with dilute hydrochloric acid and distilled water until the calcined product is neutral, and thus obtaining the three-dimensional porous graphene.
(2) Adding a distilled water solvent and three-dimensional porous graphene into a reaction bottle, adding dilute hydrochloric acid to adjust the pH value of the solution to 3 after uniform ultrasonic dispersion, ferrous chloride is added at the temperature of 30 ℃, after being uniformly stirred, a micro-sampling device is used for dropwise adding hydrogen peroxide water solution, the micro-sampling device comprises a base, a reaction bottle is arranged on the upper surface of the base, a supporting rod is fixedly connected above the base, the supporting rod is movably connected with an adjusting valve, the adjusting valve is movably connected with a movable rod, the movable rod is fixedly connected with a clamping plate, a clamping groove is arranged on the surface of the supporting rod, the clamping groove is movably connected with a clamping block, the clamping block is fixedly connected with an adjusting rod, and, the mass ratio of the three-dimensional porous graphene to the ferrous chloride to the hydrogen peroxide is 1:22:110, the three-dimensional porous graphene and the ferrous chloride are stirred at a constant speed to react for 2 hours, and the three-dimensional porous graphene is centrifugally separated, washed and dried by using distilled water to prepare the hydroxyl-enriched graphene.
(3) Adding a toluene solvent and hydroxyl-enriched graphene into a reaction bottle, ultrasonically dispersing uniformly, adding a vinyl silane coupling agent which is any one of vinyl triethoxysilane, vinyl trimethoxy silane, methyl vinyl diethoxy silane and methyl vinyl dimethoxy silane in a mass ratio of 3.5:1 with the hydroxyl-enriched graphene, stirring at a constant speed at 120 ℃ for 10 hours, centrifugally separating, washing and drying by using ethanol, and preparing the high-vinyl-content functionalized graphene.
(4) Adding a xylene solvent, methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride into a reaction bottle, uniformly stirring to prepare an acrylate mixed solution, preparing a xylene solution of functionalized graphene, uniformly dispersing by using ultrasonic waves, adding 2/3 volumes of the acrylate mixed solution, adding an initiator dibenzoyl peroxide, heating to 90 ℃ in a nitrogen atmosphere, uniformly stirring for reaction for 30min, dropwise adding the rest 1/3 volumes of the acrylate mixed solution by using a micro-sampling device, and uniformly stirring for reaction for 6h to obtain the graphene grafted succinic anhydride-water-based acrylate resin.
(5) Adding epoxy resin and graphene grafted succinic anhydride-waterborne acrylate resin into a distilled water solvent, wherein the mass ratio of functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, initiator dibenzoyl peroxide to epoxy resin is 4:1.8:14:2.5:40:0.45:100, uniformly stirring, pouring the materials into a film forming mold, and performing thermosetting film forming to prepare the graphene-anhydride curing agent modified waterborne epoxy resin material 4.
Example 5
(1) Adding graphene oxide and a distilled water solvent into a reaction bottle, after uniform ultrasonic dispersion, transferring the solution into a hydrothermal reaction kettle, heating to 190 ℃, carrying out heat preservation treatment for 10 hours, freeze-drying the solution to remove the solvent, placing the obtained graphene aerogel into the distilled water solvent, adding potassium hydroxide, wherein the mass ratio of the potassium hydroxide to the graphene aerogel is 6:1, standing for 18 hours after uniform ultrasonic dispersion, carrying out vacuum drying on the solution to remove the solvent, placing the solid mixed product into an atmosphere furnace, heating to 800 ℃ in an argon atmosphere, carrying out heat preservation treatment for 2 hours, washing the calcined product with dilute hydrochloric acid and distilled water until the calcined product is neutral, and thus obtaining the three-dimensional porous graphene.
(2) Adding a distilled water solvent and three-dimensional porous graphene into a reaction bottle, adding dilute hydrochloric acid to adjust the pH value of the solution to 2 after uniform ultrasonic dispersion, ferrous chloride is added at 40 ℃, after uniform stirring, a micro-sampling device is used for dropwise adding hydrogen peroxide water solution, the micro-sampling device comprises a base, a reaction bottle is arranged on the upper surface of the base, a supporting rod is fixedly connected above the base, the supporting rod is movably connected with a regulating valve, the regulating valve is movably connected with a movable rod, the movable rod is fixedly connected with a clamping plate, a clamping groove is arranged on the surface of the supporting rod, the clamping groove is movably connected with a clamping block, the clamping block is fixedly connected with a regulating rod, and a micro-sampler, the mass ratio of the three-dimensional porous graphene to the ferrous chloride to the hydrogen peroxide is 1:25:120, the three-dimensional porous graphene and the ferrous chloride are stirred at a constant speed to react for 2 hours, and the three-dimensional porous graphene is centrifugally separated, washed and dried by using distilled water to prepare the hydroxyl-enriched graphene.
(3) Adding a toluene solvent and hydroxyl-enriched graphene into a reaction bottle, ultrasonically dispersing uniformly, adding a vinyl silane coupling agent which is any one of vinyl triethoxysilane, vinyl trimethoxy silane, methyl vinyl diethoxy silane and methyl vinyl dimethoxy silane in a mass ratio of 4:1 to the hydroxyl-enriched graphene, stirring at a constant speed at 120 ℃ for reaction for 10 hours, centrifugally separating, washing and drying by using ethanol, and preparing the high-vinyl-content functionalized graphene.
(4) Adding a xylene solvent, methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride into a reaction bottle, uniformly stirring to prepare an acrylate mixed solution, preparing a xylene solution of functionalized graphene, uniformly dispersing by using ultrasonic waves, adding 2/3 volumes of the acrylate mixed solution, adding an initiator dibenzoyl peroxide, heating to 90 ℃ in a nitrogen atmosphere, uniformly stirring for reaction for 60min, dropwise adding the rest 1/3 volumes of the acrylate mixed solution by using a micro-sampling device, and uniformly stirring for reaction for 4-6h to obtain the graphene grafted succinic anhydride-water-based acrylate resin.
(5) Adding epoxy resin and graphene grafted succinic anhydride-waterborne acrylate resin into a distilled water solvent, wherein the mass ratio of functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, initiator dibenzoyl peroxide to epoxy resin is 5:2:15:3:45:0.5:100, uniformly stirring, pouring the materials into a film forming mold, and performing thermosetting film forming to obtain the graphene-anhydride curing agent modified waterborne epoxy resin material 5.
The impact strength of the graphene-anhydride curing agent modified waterborne epoxy resin material in examples 1-5 was tested by using a JJ-20 memory impact tester, with the test standard of CB/T1843-.
The graphene-anhydride curing agent modified waterborne epoxy resin materials in examples 1-5 were tested for tensile strength using a DR-106 tensile strength tester, with test standards GB/T1043.1-2008 and GB/T1040.2: 2006.
In summary, according to the graphene-anhydride curing agent modified waterborne epoxy resin material, the graphene hydrogel prepared by a high-pressure hydrothermal method generates a large amount of pore structures under the etching action of potassium hydroxide to form three-dimensional porous graphene with a huge specific surface area, hydrogen peroxide generates hydroxyl radicals under the action of ferrous chloride to bond with carbon atoms on the surface of the three-dimensional porous graphene to prepare hydroxylated graphene with very high hydroxyl groups, and a large amount of hydroxyl groups easily react with a vinyl silane coupling agent to obtain the functionalized graphene with high vinyl content.
Under the action of dibenzoyl peroxide, free radical polymerization is carried out on abundant ethylene groups of functionalized graphene, aqueous methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride to obtain graphene grafted succinic anhydride-aqueous acrylate resin, succinic anhydride groups are covalently grafted to the surfaces of graphene nano particles, graphene grafted succinic anhydride-water-based acrylate resin containing rich anhydride groups is used as an anhydride curing agent, the water-based acrylate with strong hydrophilicity endows the epoxy resin with good hydrophilicity, meanwhile, the anhydride group and the epoxy group in the epoxy resin are subjected to ring-opening thermosetting crosslinking reaction, graphene and a waterborne acrylate molecular chain are introduced into an epoxy resin matrix through covalent bond modification, the compatibility of the graphene nanoparticles and the epoxy resin is obviously improved, and the uniformly dispersed graphene enhances the mechanical properties of the epoxy resin, such as impact strength, tensile strength and the like.
Claims (7)
1. A graphene-anhydride curing agent modified waterborne epoxy resin material comprises the following raw materials and components, and is characterized in that: the modified graphene material comprises functionalized graphene, methacrylic acid, methyl acrylate, hydroxypropyl acrylate, maleic anhydride, an initiator and epoxy resin in a mass ratio of 0.5-5:1-2:8-15:1-3:35-45:0.3-0.5: 100.
2. The graphene-anhydride curing agent modified waterborne epoxy resin material as claimed in claim 1, wherein: the initiator is dibenzoyl peroxide.
3. The graphene-anhydride curing agent modified waterborne epoxy resin material as claimed in claim 1, wherein: the preparation method of the graphene-anhydride curing agent modified waterborne epoxy resin material comprises the following steps:
(1) adding graphene oxide into a distilled water solvent, after uniform ultrasonic dispersion, transferring the solution into a hydrothermal reaction kettle, heating to 190 ℃ for heat preservation treatment for 6-10h, removing the solvent by freeze drying, placing the obtained graphene aerogel in a potassium hydroxide solution, standing for 12-18h after uniform ultrasonic dispersion, removing the solvent by vacuum drying, placing the solid mixed product in an atmosphere furnace, heating to 800 ℃ in an argon atmosphere, performing heat preservation treatment for 1-2h, washing the calcined product by using dilute hydrochloric acid and distilled water until the calcined product is neutral, and preparing to obtain the three-dimensional porous graphene;
(2) adding three-dimensional porous graphene into a distilled water solvent, adding dilute hydrochloric acid to adjust the pH of the solution to 2-3 after uniform ultrasonic dispersion, adding ferrous chloride at 30-40 ℃, dropwise adding a hydrogen peroxide aqueous solution by using a micro-sampling device, reacting for 1-2h, performing centrifugal separation, washing and drying to prepare hydroxyl-enriched graphene;
(3) adding the hydroxylated graphene into a toluene solvent, uniformly dispersing by ultrasonic, adding a vinyl silane coupling agent, reacting for 5-10h at the temperature of 100-120 ℃, centrifugally separating, washing and drying to prepare the functionalized graphene with high vinyl content;
(4) adding methacrylic acid, methyl acrylate, hydroxypropyl acrylate and maleic anhydride into a xylene solvent, uniformly stirring to prepare an acrylate mixed solution, preparing a xylene solution of functionalized graphene, uniformly ultrasonically dispersing, adding 2/3 volumes of the acrylate mixed solution, adding an initiator dibenzoyl peroxide, heating to 80-90 ℃ in a nitrogen atmosphere, reacting for 30-60min, dropwise adding the rest 1/3 volumes of the acrylate mixed solution by using a micro-sampling device, and reacting for 4-6h to obtain the graphene grafted succinic anhydride-water-based acrylate resin;
(5) adding epoxy resin and graphene grafted succinic anhydride-waterborne acrylate resin into a distilled water solvent, uniformly stirring, pouring the materials into a film forming mold, and performing thermosetting film forming to prepare the graphene-anhydride curing agent modified waterborne epoxy resin material.
4. The graphene-anhydride curing agent modified waterborne epoxy resin material as claimed in claim 3, wherein: the mass ratio of the graphene aerogel and the potassium hydroxide in the step (1) is 1: 3-6.
5. The graphene-anhydride curing agent modified waterborne epoxy resin material as claimed in claim 3, wherein: the mass ratio of the three-dimensional porous graphene, the ferrous chloride and the hydrogen peroxide in the step (2) is 1:15-25: 80-120.
6. The graphene-anhydride curing agent modified waterborne epoxy resin material as claimed in claim 3, wherein: the micro-sampling device in step (2) comprises a base, a reaction bottle arranged on the upper surface of the base, a supporting rod fixedly connected with the upper part of the base, a regulating valve movably connected with the supporting rod, a movable rod movably connected with the regulating valve, a clamping plate fixedly connected with the movable rod, a clamping groove arranged on the surface of the supporting rod, a clamping block movably connected with the clamping block, a regulating rod fixedly connected with the clamping plate, and a micro-sampler fixedly connected with the clamping groove and the regulating rod.
7. The graphene-anhydride curing agent modified waterborne epoxy resin material as claimed in claim 3, wherein: the vinyl silane coupling agent in the step (3) is any one of vinyl triethoxysilane, vinyl trimethoxysilane, methyl vinyl diethoxy silane and methyl vinyl dimethoxy silane, and the mass ratio of the vinyl silane coupling agent to the hydroxyl-rich graphene is 1-4: 1.
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| CN111718638A (en) * | 2020-07-16 | 2020-09-29 | 王康 | Functionalized graphene-water-based epoxy resin anticorrosive material and preparation method thereof |
| CN112625553A (en) * | 2020-12-28 | 2021-04-09 | 陕西科技大学 | Latent self-curing resin coating composition and construction method thereof |
| CN114539551A (en) * | 2022-03-23 | 2022-05-27 | 华南农业大学 | Modified graphene oxide/elaeostearic acid maleic anhydride vinyl ester anticorrosive resin and preparation method and application thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111718638A (en) * | 2020-07-16 | 2020-09-29 | 王康 | Functionalized graphene-water-based epoxy resin anticorrosive material and preparation method thereof |
| CN112625553A (en) * | 2020-12-28 | 2021-04-09 | 陕西科技大学 | Latent self-curing resin coating composition and construction method thereof |
| CN112625553B (en) * | 2020-12-28 | 2022-02-01 | 陕西科技大学 | Latent self-curing resin coating composition and construction method thereof |
| CN114656750A (en) * | 2021-12-31 | 2022-06-24 | 华侨大学 | Outdoor epoxy resin-based anti-ultraviolet aging insulating material, preparation method and application |
| CN114539551A (en) * | 2022-03-23 | 2022-05-27 | 华南农业大学 | Modified graphene oxide/elaeostearic acid maleic anhydride vinyl ester anticorrosive resin and preparation method and application thereof |
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