阅读说明：本技术 一种高热稳定性的石墨烯-环氧树脂改性聚氨酯材料及制法 (Graphene-epoxy resin modified polyurethane material with high thermal stability and preparation method thereof ) 是由 覃翠连 于 2020-11-23 设计创作，主要内容包括：本发明涉及聚氨酯技术领域,且公开了一种高热稳定性的石墨烯-环氧树脂改性聚氨酯材料,巯基乙胺和氧化石墨烯缩合,再与环氧树脂反应,然后二乙醇胺与环氧官能团反应,得到石墨烯接枝羟基环氧树脂,参与到聚氨酯聚合过程中,得到石墨烯-环氧树脂改性聚氨酯材料,通过共价接枝,石墨烯和环氧树脂高度分散在水性聚氨酯基体中,减少了团聚现象,石墨烯形成三维网状结构,提高了水性聚氨酯的热稳定性,同时提高了水性聚氨酯的力学性能,环氧树脂与水性聚氨酯形成交联网状结构,进一步提高了水性聚氨酯的热稳定性和力学性能,赋予了石墨烯-环氧树脂改性聚氨酯材料优异的热稳定性、力学性能。(The invention relates to the technical field of polyurethane, and discloses a graphene-epoxy resin modified polyurethane material with high thermal stability, wherein mercaptoethylamine and graphene oxide are condensed and then react with epoxy resin, and then diethanolamine reacts with an epoxy functional group to obtain graphene grafted hydroxyl epoxy resin, the graphene grafted hydroxyl epoxy resin participates in the polyurethane polymerization process to obtain a graphene-epoxy resin modified polyurethane material, the graphene and the epoxy resin are highly dispersed in a waterborne polyurethane matrix through covalent grafting, the agglomeration phenomenon is reduced, the graphene forms a three-dimensional network structure, the thermal stability of the waterborne polyurethane is improved, the mechanical property of the waterborne polyurethane is improved at the same time, the epoxy resin and the waterborne polyurethane form a cross-linked network structure, the thermal stability and the mechanical property of the waterborne polyurethane are further improved, and the graphene-epoxy resin modified polyurethane material is endowed with excellent thermal stability, Mechanical properties.)

1. A graphene-epoxy resin modified polyurethane material with high thermal stability is characterized in that: the preparation method of the graphene-epoxy resin modified polyurethane material with high thermal stability comprises the following steps:

(1) adding 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, mercaptoethylamine and graphene oxide into a solvent dimethyl sulfoxide according to the mass ratio of 20-30:40-60:10, uniformly stirring, placing in a water bath stirrer, stirring and reacting for 24-72h at 35-45 ℃, centrifuging, washing and drying to obtain mercaptolated graphene;

(2) adding epoxy resin E51 and a catalyst 1, 8-bis-dimethylamino-naphthalene into deionized water, uniformly stirring, adding thiolated graphene, uniformly stirring, placing in a torque rheometer, and reacting at the temperature of 200-;

(3) adding graphene grafted epoxy resin into acetone, stirring and preheating at 50-70 ℃ for 20-40min, slowly dropwise adding diethanolamine, reacting at constant temperature for 3-5h, and distilling under reduced pressure to obtain graphene grafted hydroxyl epoxy resin;

(4) adding polypropylene glycol into poly adipic acid-1, 4-butanediol ester diol in nitrogen atmosphere, vacuum dehydrating at 100-120 deg.C for 1-2h, cooling, adding toluene diisocyanate, stirring, reacting for 1-3h at 80-90 ℃, cooling, adding hydrophilic chain extender 2, 2-dimethylolpropionic acid, chain extender 1, 4-butanediol, graphene grafted hydroxyl epoxy resin and catalyst dibutyltin dilaurate, adding a proper amount of acetone to adjust viscosity, reacting at 60-70 deg.C for 4-6h, cooling, neutralizing prepolymer with triethylamine, adding deionized water for high-speed emulsification, vacuum distilling, pouring into glass template, air-drying at room temperature to form a film and drying to obtain the graphene-epoxy resin modified polyurethane material with high thermal stability.

2. The graphene-epoxy resin modified polyurethane material with high thermal stability according to claim 1, wherein: the water bath stirring instrument in the step (1) comprises a main body, a motor is movably connected to the bottom of the main body, a driving wheel is movably connected to the top of the motor, a driven wheel is movably connected to the left side of the driving wheel, a connecting rod is movably connected to the top of the driving wheel, a driven wheel is movably connected to the top of the connecting rod, a magnet is movably connected to the right side of the driven wheel, a partition plate is movably connected to the middle of the main body, and a beaker is movably connected to the top.

3. The graphene-epoxy resin modified polyurethane material with high thermal stability according to claim 1, wherein: the mass ratio of the epoxy resin E51, the 1, 8-bis-dimethylamino-naphthalene and the sulfhydrylation graphene in the step (2) is 100:0.5-1.5: 15-35.

4. The graphene-epoxy resin modified polyurethane material with high thermal stability according to claim 1, wherein: the mass ratio of the graphene grafted epoxy resin to the diethanolamine in the step (3) is 100: 10-25.

5. The graphene-epoxy resin modified polyurethane material with high thermal stability according to claim 1, wherein: in the step (4), the mass ratio of the poly adipic acid-1, 4-butanediol ester diol, the polypropylene glycol, the toluene diisocyanate, the 2, 2-dimethylolpropionic acid, the 1, 4-butanediol, the graphene grafted hydroxyl epoxy resin and the dibutyltin dilaurate is 100:14-18:50-65:7-9:12-20:15-25: 1-2.

Technical Field

The invention relates to the technical field of polyurethane, in particular to a graphene-epoxy resin modified polyurethane material with high thermal stability and a preparation method thereof.

Background

With the development of scientific technology, more and more new materials are developed, the damage to the environment is increased, and the environmental pollution is more and more serious, so that environment-friendly materials are required to be developed, the pollution to the environment is reduced, the polyurethane has the advantages of low temperature resistance, strong adhesive force, good flexibility and the like, the polyurethane is widely applied to the fields of coatings, adhesives, elastomers and the like, people modify the polyurethane in a water-based manner, and the polyurethane becomes an environment-friendly material which is environment-friendly, energy-saving, green and pollution-free, and has a wide application prospect.

However, due to the hydrophilic groups introduced into the molecules of the waterborne polyurethane and the defects of low molecular weight and the like, the waterborne polyurethane has poor thermal stability and poor mechanical property, the application of the waterborne polyurethane is greatly limited, the epoxy resin has excellent thermal stability and mechanical property, and the graphene has ultrahigh specific surface area, good heat conductivity and mechanical property, and is subjected to synergistic modification treatment to improve the thermal stability and mechanical property of the waterborne polyurethane, but the graphene is easy to agglomerate in an organic matrix to influence the addition effect of the graphene, so that the problems are solved by adopting a mode of modifying a polyurethane material by the graphene-epoxy resin.

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a graphene-epoxy resin modified polyurethane material with high thermal stability and a preparation method thereof, and solves the problem that the waterborne polyurethane has poor thermal stability and mechanical property.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: a graphene-epoxy resin modified polyurethane material with high thermal stability is prepared by the following steps:

(1) adding a solvent dimethyl sulfoxide, 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, mercaptoethylamine and graphene oxide into a reaction bottle, wherein the mass ratio of the dimethyl sulfoxide to the 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride to the mercaptoethylamine to the graphene oxide is 20-30:40-60:10, uniformly stirring, placing the mixture into a water bath stirrer, stirring and reacting for 24-72 hours at 35-45 ℃, centrifuging, washing with acetone and deionized water, and drying to obtain mercaptolated graphene;

(2) adding deionized water, epoxy resin E51 and a catalyst 1, 8-bis-dimethylamino naphthalene into a reaction bottle, uniformly stirring, adding thiolated graphene, uniformly stirring, placing in a torque rheometer, and reacting at the temperature of 200-;

(3) adding acetone and graphene grafted epoxy resin into a reaction bottle, stirring and preheating at 50-70 ℃ for 20-40min, slowly dropwise adding diethanolamine, reacting at constant temperature for 3-5h, and removing acetone by reduced pressure distillation to obtain graphene grafted hydroxy epoxy resin;

(4) adding poly adipic acid-1, 4-butanediol ester diol and polypropylene glycol into a reaction bottle in nitrogen atmosphere, vacuum dehydrating at 100-120 deg.C for 1-2h, cooling, adding toluene diisocyanate, stirring, reacting for 1-3h at 80-90 ℃, cooling, adding hydrophilic chain extender 2, 2-dimethylolpropionic acid, chain extender 1, 4-butanediol, graphene grafted hydroxyl epoxy resin and catalyst dibutyltin dilaurate, adding a proper amount of acetone to adjust viscosity, reacting for 4-6h at 60-70 ℃, cooling, neutralizing the prepolymer with triethylamine, adding deionized water for high-speed emulsification, distilling under reduced pressure to remove acetone, pouring into a glass template, air-drying at room temperature to form a film and drying to obtain the graphene-epoxy resin modified polyurethane material with high thermal stability.

Preferably, the water bath stirring instrument in the step (1) comprises a main body, a motor is movably connected to the bottom of the main body, a driving wheel is movably connected to the top of the motor, a driven wheel is movably connected to the left side of the driving wheel, a connecting rod is movably connected to the top of the driving wheel, a driven wheel is movably connected to the top of the connecting rod, a magnet is movably connected to the right side of the driven wheel, a partition plate is movably connected to the middle of the main body, and a beaker is movably connected to the top of.

Preferably, the mass ratio of the epoxy resin E51, the 1, 8-bis-dimethylamino-naphthalene and the thiolated graphene in the step (2) is 100:0.5-1.5: 15-35.

Preferably, the mass ratio of the graphene grafted epoxy resin to the diethanolamine in the step (3) is 100: 10-25.

Preferably, in the step (4), the mass ratio of the poly adipic acid-1, 4-butanediol ester diol, the polypropylene glycol, the toluene diisocyanate, the 2, 2-dimethylolpropionic acid, the 1, 4-butanediol, the graphene grafted hydroxy epoxy resin and the dibutyltin dilaurate is 100:14-18:50-65:7-9:12-20:15-25: 1-2.

(III) advantageous technical effects

Compared with the prior art, the invention has the following beneficial technical effects:

according to the graphene-epoxy resin modified polyurethane material with high thermal stability, under the action of a cross-linking agent 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, amino on mercaptoethylamine is condensed with carboxyl on graphene oxide to generate amido bond, mercaptoethylamine is grafted to graphene oxide to obtain mercaptolated graphene, under the action of an alkaline catalyst 1, 8-bis-dimethylamino naphthalene, mercapto on the mercaptolated graphene loses hydrogen ions to form mercaptan anions with strong nucleophilicity, the mercaptan anions attack epoxy functional groups of the epoxy resin and the ring opening form alkoxide anion intermediate products, the hydrogen ions in a reaction system are captured, the mercaptolated graphene and the epoxy resin are subjected to covalent grafting to obtain graphene grafted epoxy resin, and at a lower temperature, the imino group of diethanolamine and the epoxy functional groups undergo a ring opening reaction, and grafting the graphene-epoxy resin modified polyurethane material onto an epoxy resin matrix to hydroxylate epoxy resin to obtain graphene grafted hydroxyl epoxy resin which contains rich hydroxyl and participates in the polyurethane polymerization process to obtain the graphene-epoxy resin modified polyurethane material.

According to the graphene-epoxy resin modified polyurethane material with high thermal stability, through covalent grafting, graphene and epoxy resin are highly dispersed in a waterborne polyurethane matrix, the agglomeration phenomenon is reduced, the graphene forms a three-dimensional network structure, the heat conduction path is increased, the contact thermal resistance and the interface thermal resistance are reduced, the propagation rate of phonons is accelerated, the thermal stability of the waterborne polyurethane is improved, meanwhile, the mechanical property of the waterborne polyurethane is greatly improved due to the excellent mechanical property of the graphene, the epoxy resin containing abundant hydroxyl groups forms a cross-linked network structure in the synthesis process of the waterborne polyurethane, so that the waterborne polyurethane matrix contains abundant rigid benzene ring structures, the cross-linking density is improved, the thermal stability and the mechanical property of the waterborne polyurethane are further improved, the graphene-epoxy resin modified polyurethane material is endowed with excellent thermal stability, Mechanical properties.

Drawings

FIG. 1 is a schematic front view of a water bath stirrer;

FIG. 2 is a first schematic view of a gear structure;

fig. 3 is a schematic view of a gear structure two.

1. A main body; 2. a motor; 3. a driving wheel; 4. a driven wheel; 5. a connecting rod; 6. a driven wheel; 7. a magnet; 8. a partition plate; 9. and (4) a beaker.

Detailed Description

To achieve the above object, the present invention provides the following embodiments and examples: a graphene-epoxy resin modified polyurethane material with high thermal stability is prepared by the following steps:

(1) adding dimethyl sulfoxide, 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, mercaptoethylamine and graphene oxide which are used as solvents in a mass ratio of 20-30:40-60:10 into a reaction bottle, uniformly stirring, placing in a water bath stirrer, the water bath stirring instrument comprises a main body, wherein the bottom of the main body is movably connected with a motor, the top of the motor is movably connected with a driving wheel, the left side of the driving wheel is movably connected with a driven wheel, the top of the driving wheel is movably connected with a connecting rod, the top of the connecting rod is movably connected with a driven wheel, the right side of the driven wheel is movably connected with a magnet, the middle of the main body is movably connected with a clapboard, the top of the clapboard is movably connected, stirring and reacting for 24-72h at 35-45 ℃, centrifuging, washing with acetone and deionized water, and drying to obtain sulfhydrylated graphene;

(2) adding deionized water, epoxy resin E51 and a catalyst 1, 8-bis-dimethylamino naphthalene into a reaction bottle, uniformly stirring, adding thiolated graphene, wherein the mass ratio of the epoxy resin E51 to the 1, 8-bis-dimethylamino naphthalene to the thiolated graphene is 100:0.5-1.5:15-35, uniformly stirring, placing in a torque rheometer, and reacting at 260 ℃ for 40-80min to obtain graphene grafted epoxy resin;

(3) adding acetone and graphene grafted epoxy resin into a reaction bottle, stirring and preheating for 20-40min at 50-70 ℃, slowly dropwise adding diethanolamine, reacting at constant temperature for 3-5h with the mass ratio of the graphene grafted epoxy resin to the diethanolamine being 100:10-25, and removing the acetone by reduced pressure distillation to obtain graphene grafted hydroxyl epoxy resin;

(4) adding poly (1, 4-butanediol adipate) glycol and polypropylene glycol into a reaction bottle in a nitrogen atmosphere, carrying out vacuum dehydration for 1-2h at the temperature of 100-120 ℃, cooling, adding toluene diisocyanate, stirring uniformly, reacting for 1-3h at the temperature of 80-90 ℃, cooling, adding a hydrophilic chain extender 2, 2-dimethylolpropionic acid, a chain extender 1, 4-butanediol, graphene grafted hydroxyl epoxy resin and a catalyst dibutyltin dilaurate, wherein the mass ratio of the poly (1, 4-butanediol adipate) glycol, the polypropylene glycol, the toluene diisocyanate, the 2, 2-dimethylolpropionic acid, the 1, 4-butanediol, the graphene grafted hydroxyl epoxy resin and the dibutyltin dilaurate is 100:14-18:50-65:7-9:12-20:15-25:1-2, and adding a proper amount of acetone to adjust viscosity, reacting for 4-6h at 60-70 ℃, cooling, neutralizing the prepolymer with triethylamine, adding deionized water to perform high-speed emulsification, distilling under reduced pressure to remove acetone, pouring into a glass template, air-drying at room temperature to form a film, and drying to obtain the graphene-epoxy resin modified polyurethane material with high thermal stability.

Example 1

(1) Adding solvents of dimethyl sulfoxide, 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, mercaptoethylamine and graphene oxide into a reaction bottle, wherein the mass ratio of the dimethyl sulfoxide to the 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride to the mercaptoethylamine to the graphene oxide is 20:40:10, uniformly stirring, placing the mixture into a water bath stirrer, wherein the water bath stirrer comprises a main body, the bottom of the main body is movably connected with a motor, the top of the motor is movably connected with a driving wheel, the left side of the driving wheel is movably connected with a driven wheel, the top of the driving wheel is movably connected with a connecting rod, the top of the connecting rod is movably connected with a driven wheel, the right side of the driven wheel is movably connected with a magnet, the middle of the main body is movably connected with a partition plate, the top of the partition plate is movably connected with;

(2) adding deionized water, epoxy resin E51 and a catalyst 1, 8-bis-dimethylamino naphthalene into a reaction bottle, uniformly stirring, adding thiolated graphene, wherein the mass ratio of the epoxy resin E51 to the 1, 8-bis-dimethylamino naphthalene to the thiolated graphene is 100:0.5:15, uniformly stirring, placing in a torque rheometer, and reacting for 40min at 200 ℃ to obtain graphene grafted epoxy resin;

(3) adding acetone and graphene grafted epoxy resin into a reaction bottle, stirring and preheating for 20min at 50 ℃, slowly dropwise adding diethanolamine, reacting for 3h at constant temperature, and distilling under reduced pressure to remove acetone to obtain graphene grafted hydroxy epoxy resin, wherein the mass ratio of the graphene grafted epoxy resin to the diethanolamine is 100: 10;

(4) adding poly (1, 4-butanediol adipate) glycol and polypropylene glycol into a reaction bottle in a nitrogen atmosphere, carrying out vacuum dehydration for 1h at 100 ℃, cooling, adding toluene diisocyanate, uniformly stirring, reacting for 1h at 80 ℃, cooling, adding a hydrophilic chain extender 2, 2-dimethylolpropionic acid, a chain extender 1, 4-butanediol, graphene grafted hydroxyl epoxy resin and a catalyst dibutyltin dilaurate, wherein the mass ratio of the poly (1, 4-butanediol adipate) glycol, the polypropylene glycol, the toluene diisocyanate, the 2, 2-dimethylolpropionic acid, the 1, 4-butanediol, the graphene grafted hydroxyl epoxy resin and the dibutyltin dilaurate is 100:14:50:7:12:15:1, adding an appropriate amount of acetone for adjusting the viscosity, reacting for 4h at 60 ℃, and cooling, neutralizing the prepolymer with triethylamine, adding deionized water for high-speed emulsification, distilling under reduced pressure to remove acetone, pouring into a glass template, air-drying at room temperature to form a film, and drying to obtain the graphene-epoxy resin modified polyurethane material with high thermal stability.

Example 2

(1) Adding solvents of dimethyl sulfoxide, 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, mercaptoethylamine and graphene oxide into a reaction bottle, wherein the mass ratio of the dimethyl sulfoxide to the 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride to the mercaptoethylamine to the graphene oxide is 25:50:10, uniformly stirring, placing the mixture into a water bath stirrer, wherein the water bath stirrer comprises a main body, the bottom of the main body is movably connected with a motor, the top of the motor is movably connected with a driving wheel, the left side of the driving wheel is movably connected with a driven wheel, the top of the driving wheel is movably connected with a connecting rod, the top of the connecting rod is movably connected with a driven wheel, the right side of the driven wheel is movably connected with a magnet, the middle of the main body is movably connected with a partition plate, the top of the partition plate is movably connected with;

(2) adding deionized water, epoxy resin E51 and a catalyst 1, 8-bis-dimethylamino naphthalene into a reaction bottle, uniformly stirring, adding thiolated graphene, wherein the mass ratio of the epoxy resin E51 to the 1, 8-bis-dimethylamino naphthalene to the thiolated graphene is 100:1:25, uniformly stirring, placing in a torque rheometer, and reacting for 60min at 230 ℃ to obtain graphene grafted epoxy resin;

(3) adding acetone and graphene grafted epoxy resin into a reaction bottle, stirring and preheating for 30min at 60 ℃, slowly dropwise adding diethanolamine, reacting for 4h at constant temperature, and distilling under reduced pressure to remove acetone to obtain graphene grafted hydroxy epoxy resin, wherein the mass ratio of the graphene grafted epoxy resin to the diethanolamine is 100: 18;

(4) adding poly (1, 4-butanediol adipate) glycol and polypropylene glycol into a reaction bottle in a nitrogen atmosphere, carrying out vacuum dehydration for 1.5h at 110 ℃, cooling, adding toluene diisocyanate, stirring uniformly, reacting for 2h at 85 ℃, cooling, adding a hydrophilic chain extender 2, 2-dimethylolpropionic acid, a chain extender 1, 4-butanediol, graphene grafted hydroxyl epoxy resin and a catalyst dibutyltin dilaurate, wherein the mass ratio of the poly (1, 4-butanediol adipate), the polypropylene glycol, the toluene diisocyanate, the 2, 2-dimethylolpropionic acid, the 1, 4-butanediol, the graphene grafted hydroxyl epoxy resin and the dibutyltin dilaurate is 100:16:58:8:16:20:1.5, adding a proper amount of acetone for adjusting the viscosity, reacting for 5h at 65 ℃, and cooling, neutralizing the prepolymer with triethylamine, adding deionized water for high-speed emulsification, distilling under reduced pressure to remove acetone, pouring into a glass template, air-drying at room temperature to form a film, and drying to obtain the graphene-epoxy resin modified polyurethane material with high thermal stability.

Example 3

(1) Adding a solvent dimethyl sulfoxide, 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, mercaptoethylamine and graphene oxide into a reaction bottle, wherein the mass ratio of the dimethyl sulfoxide to the 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride to the graphene oxide is 30:60:10, uniformly stirring, placing the mixture into a water bath stirrer, wherein the water bath stirrer comprises a main body, the bottom of the main body is movably connected with a motor, the top of the motor is movably connected with a driving wheel, the left side of the driving wheel is movably connected with a driven wheel, the top of the driving wheel is movably connected with a connecting rod, the top of the connecting rod is movably connected with a driven wheel, the right side of the driven wheel is movably connected with a magnet, the middle of the main body is movably connected with a partition plate, the top of the partition plate is movably connected with a beaker, stirring;

(2) adding deionized water, epoxy resin E51 and a catalyst 1, 8-bis-dimethylamino naphthalene into a reaction bottle, uniformly stirring, adding thiolated graphene, wherein the mass ratio of the epoxy resin E51 to the 1, 8-bis-dimethylamino naphthalene to the thiolated graphene is 100:1.5:35, uniformly stirring, placing in a torque rheometer, and reacting for 80min at 260 ℃ to obtain graphene grafted epoxy resin;

(3) adding acetone and graphene grafted epoxy resin into a reaction bottle, stirring and preheating for 40min at 70 ℃, slowly dropwise adding diethanolamine, reacting for 5h at constant temperature, and distilling under reduced pressure to remove acetone to obtain graphene grafted hydroxy epoxy resin, wherein the mass ratio of the graphene grafted epoxy resin to the diethanolamine is 100: 25;

(4) adding poly (1, 4-butanediol adipate) glycol and polypropylene glycol into a reaction bottle in a nitrogen atmosphere, carrying out vacuum dehydration for 2h at 120 ℃, cooling, adding toluene diisocyanate, uniformly stirring, reacting for 3h at 90 ℃, cooling, adding a hydrophilic chain extender 2, 2-dimethylolpropionic acid, a chain extender 1, 4-butanediol, graphene grafted hydroxyl epoxy resin and a catalyst dibutyltin dilaurate, wherein the mass ratio of the poly (1, 4-butanediol adipate) glycol, the polypropylene glycol, the toluene diisocyanate, the 2, 2-dimethylolpropionic acid, the 1, 4-butanediol, the graphene grafted hydroxyl epoxy resin and the dibutyltin dilaurate is 100:18:65:9:20:25:2, adding an appropriate amount of acetone for adjusting the viscosity, reacting for 6h at 70 ℃, and cooling, neutralizing the prepolymer with triethylamine, adding deionized water for high-speed emulsification, distilling under reduced pressure to remove acetone, pouring into a glass template, air-drying at room temperature to form a film, and drying to obtain the graphene-epoxy resin modified polyurethane material with high thermal stability.

Comparative example 1

(1) Adding a solvent dimethyl sulfoxide, 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, mercaptoethylamine and graphene oxide into a reaction bottle, wherein the mass ratio of the dimethyl sulfoxide to the 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride to the graphene oxide is 15:30:10, uniformly stirring, placing the mixture into a water bath stirrer, wherein the water bath stirrer comprises a main body, the bottom of the main body is movably connected with a motor, the top of the motor is movably connected with a driving wheel, the left side of the driving wheel is movably connected with a driven wheel, the top of the driving wheel is movably connected with a connecting rod, the top of the connecting rod is movably connected with a driven wheel, the right side of the driven wheel is movably connected with a magnet, the middle of the main body is movably connected with a partition plate, the top of the partition plate is movably connected with a beaker, stirring;

(2) adding deionized water, epoxy resin E51 and a catalyst 1, 8-bis-dimethylamino naphthalene into a reaction bottle, uniformly stirring, adding thiolated graphene, wherein the mass ratio of the epoxy resin E51 to the 1, 8-bis-dimethylamino naphthalene to the thiolated graphene is 100:0.3:10, uniformly stirring, placing in a torque rheometer, and reacting for 40min at 200 ℃ to obtain graphene grafted epoxy resin;

(3) adding acetone and graphene grafted epoxy resin into a reaction bottle, stirring and preheating for 20min at 50 ℃, slowly dropwise adding diethanolamine, reacting for 3h at constant temperature, and distilling under reduced pressure to remove acetone to obtain graphene grafted hydroxy epoxy resin, wherein the mass ratio of the graphene grafted epoxy resin to the diethanolamine is 100: 5;

(4) adding poly (1, 4-butanediol adipate) glycol and polypropylene glycol into a reaction bottle in a nitrogen atmosphere, carrying out vacuum dehydration for 1h at 100 ℃, cooling, adding toluene diisocyanate, uniformly stirring, reacting for 1h at 80 ℃, cooling, adding a hydrophilic chain extender 2, 2-dimethylolpropionic acid, a chain extender 1, 4-butanediol, graphene grafted hydroxyl epoxy resin and a catalyst dibutyltin dilaurate, wherein the mass ratio of the poly (1, 4-butanediol adipate) glycol, the polypropylene glycol, the toluene diisocyanate, the 2, 2-dimethylolpropionic acid, the 1, 4-butanediol, the graphene grafted hydroxyl epoxy resin and the dibutyltin dilaurate is 100:10:45:6:10:10:0.5, adding a proper amount of acetone for adjusting the viscosity, reacting for 4h at 60 ℃, and cooling, neutralizing the prepolymer with triethylamine, adding deionized water for high-speed emulsification, distilling under reduced pressure to remove acetone, pouring into a glass template, air-drying at room temperature to form a film, and drying to obtain the graphene-epoxy resin modified polyurethane material with high thermal stability.

Comparative example 2

(1) Adding solvents of dimethyl sulfoxide, 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride, mercaptoethylamine and graphene oxide into a reaction bottle, wherein the mass ratio of the dimethyl sulfoxide to the 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride to the mercaptoethylamine to the graphene oxide is 40:80:10, uniformly stirring, placing the mixture into a water bath stirrer, wherein the water bath stirrer comprises a main body, the bottom of the main body is movably connected with a motor, the top of the motor is movably connected with a driving wheel, the left side of the driving wheel is movably connected with a driven wheel, the top of the driving wheel is movably connected with a connecting rod, the top of the connecting rod is movably connected with a driven wheel, the right side of the driven wheel is movably connected with a magnet, the middle of the main body is movably connected with a partition plate, the top of the partition plate is movably connected with;

(2) adding deionized water, epoxy resin E51 and a catalyst 1, 8-bis-dimethylamino naphthalene into a reaction bottle, uniformly stirring, adding thiolated graphene, wherein the mass ratio of the epoxy resin E51 to the 1, 8-bis-dimethylamino naphthalene to the thiolated graphene is 100:2:45, uniformly stirring, placing in a torque rheometer, and reacting for 80min at 260 ℃ to obtain graphene grafted epoxy resin;

(3) adding acetone and graphene grafted epoxy resin into a reaction bottle, stirring and preheating for 40min at 70 ℃, slowly dropwise adding diethanolamine, reacting for 5h at constant temperature, and distilling under reduced pressure to remove acetone to obtain graphene grafted hydroxy epoxy resin, wherein the mass ratio of the graphene grafted epoxy resin to the diethanolamine is 100: 40;

(4) adding poly (1, 4-butanediol adipate) glycol and polypropylene glycol into a reaction bottle in a nitrogen atmosphere, carrying out vacuum dehydration for 2h at 120 ℃, cooling, adding toluene diisocyanate, uniformly stirring, reacting for 3h at 90 ℃, cooling, adding a hydrophilic chain extender 2, 2-dimethylolpropionic acid, a chain extender 1, 4-butanediol, graphene grafted hydroxyl epoxy resin and a catalyst dibutyltin dilaurate, wherein the mass ratio of the poly (1, 4-butanediol adipate) glycol, the polypropylene glycol, the toluene diisocyanate, the 2, 2-dimethylolpropionic acid, the 1, 4-butanediol, the graphene grafted hydroxyl epoxy resin and the dibutyltin dilaurate is 100:20:75:12:25:30:2.5, adding a proper amount of acetone for adjusting the viscosity, reacting for 6h at 70 ℃, and cooling, neutralizing the prepolymer with triethylamine, adding deionized water for high-speed emulsification, distilling under reduced pressure to remove acetone, pouring into a glass template, air-drying at room temperature to form a film, and drying to obtain the graphene-epoxy resin modified polyurethane material with high thermal stability.

The initial thermal decomposition temperature and the maximum thermal decomposition temperature of the graphene-epoxy resin modified polyurethane materials with high thermal stability obtained in the examples and the comparative examples at room temperature are measured by using an MI-BP thermogravimetric analyzer, and the test standard is GB/T31850-2015.

The tensile strength of the graphene-epoxy resin modified polyurethane materials with high thermal stability obtained in the examples and the comparative examples is tested by using a WDW-5 type universal testing machine, and the test standard is GB/T1040.3-2006.