A kind of antistatic polyurethane foam based on graphene and preparation method thereof

Abstract

The invention discloses a kind of antistatic polyurethane foam based on graphene and preparation method thereof, in the scheme, antistatic agent, surfactant, dibutyltin dilaurate, triethylene diamine, foaming agent, 1,2-propylene glycol and glycerol, polyether polyol, isocyanate and other components are mixed, foaming forms polyurethane foam;The present application first carries out surface treatment to ATO powder by silane coupling agent KH-550, to obtain amino-modified ATO powder, then it is loaded to graphene surface, on the one hand, graphene can be used to improve the dispersibility of ATO powder, on the other hand, ATO powder and graphene are compounded in the scheme, to form a conductive path, and its antistatic performance is far better than simple ATO powder, and the amount added by ATO powder is relatively less. The process design of the present invention is reasonable, and the component ratio is suitable, and the polyurethane foam prepared has excellent antistatic performance, excellent flame retardant performance, and the mechanical properties of the product are also improved, with high practicality.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane foam, in particular to a graphene-based antistatic polyurethane foam and a preparation method thereof. Background Art

[0002] Polyurethane rigid foam is a high molecular polymer made of isocyanate and polyether as the main raw materials, mixed with a variety of additives such as foaming agent, catalyst, flame retardant, etc. through special equipment, and foamed on-site by high-pressure spraying. Polyurethane foam is divided into two types: soft foam and hard foam. Soft foam has an open-cell structure, while hard foam has a closed-cell structure; soft foam is divided into two types: crusting and non-skinning.

[0003] In the current research and development process of polyurethane foam, flame retardancy and antistatic properties are the properties that researchers in this field are more concerned about. ATO powder is a more commonly used antistatic agent, but ATO is in powder form and is easy to agglomerate in polyurethane foam, with poor dispersibility. When used as an antistatic agent, a large amount needs to be added to form a conductive path, which is actually easy to affect the mechanical properties of the product.

[0004] Based on this situation, the present application discloses a graphene-based antistatic polyurethane foam and a preparation method thereof to solve this technical problem. Summary of the invention

[0005] The object of the present invention is to provide an antistatic polyurethane foam based on graphene and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A method for preparing an antistatic polyurethane foam based on graphene comprises the following steps:

[0008] S1: Take graphene oxide and N,N-dimethylformamide solution, ultrasonically disperse for 20-30 minutes to obtain graphene dispersion, add flame retardant ATO powder, adjust the pH to 9-10 with sodium hydroxide, stir and react in a water bath at 80-85°C for 20-24 hours, add hydrazine hydrate, continue to react for 7-8 hours, collect the product by centrifugation after the reaction is completed, wash to neutrality, and dry to obtain an antistatic agent;

[0009] S2: Take antistatic agent, surfactant, dibutyltin dilaurate, triethylenediamine, foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 20-30 minutes, add isocyanate, stir for 30-40 seconds, inject into the mold for foaming, and mature at 60-65°C for 10-12 hours to obtain the finished polyurethane foam.

[0010] In a more optimized solution, in step S2, the contents of each component are: by weight, 100-105 parts of polyether polyol, 105-110 parts of isocyanate, 15-20 parts of antistatic agent, 1-1.5 parts of surfactant, 0.2-0.3 parts of dibutyltin dilaurate, 0.5-0.8 parts of triethylenediamine, 3-4 parts of foaming agent, 1-1.2 parts of 1,2-propylene glycol, and 1-1.2 parts of glycerol.

[0011] In a more optimized solution, in step S2, the foaming agent is deionized water; the surfactant is fatty acid glyceride; in step S1, the concentration of the graphene dispersion is 8-10 g / L, and the mass ratio of the graphene oxide to the flame retardant ATO powder is 2:3.

[0012] In a more optimized solution, in step S1, the specific preparation steps of the flame retardant ATO powder are:

[0013] S11: Mix KH-550, anhydrous ethanol and deionized water, and perform ultrasonic dispersion for 20-30 min to obtain solution A;

[0014] Take ATO powder and deionized water, ultrasonically disperse for 50-60 minutes, add solution A, stir and react in a water bath at 50-55°C for 8-9 hours, collect the product after the reaction, wash and dry to obtain amino-modified ATO powder;

[0015] S12: Mix 4,4-diaminodiphenylmethane and triethylamine, add acetonitrile and stir to dissolve, add acetonitrile solution of phenyl dichlorophosphate, stir for 20-30 minutes, then add amino-modified ATO powder, heat to 70-75°C under nitrogen environment, keep warm for 6-8 hours, remove the solvent after the reaction, wash and dry to obtain flame-retardant ATO powder.

[0016] According to a more optimized solution, in step S12, the molar ratio of phenyl dichlorophosphate, 4,4-diaminodiphenylmethane, and amino-modified ATO powder is 8:5:2; and the molar ratio of triethylamine and 4,4-diaminodiphenylmethane is 1.2:1.

[0017] In a more optimized solution, the ATO powder is magnetic ATO powder, and the preparation steps of the magnetic ATO powder are:

[0018] Take acrylic acid, deionized water and anhydrous ethanol, mix and stir evenly, add tin tetrachloride and antimony trichloride, and ultrasonically disperse for 20-30 minutes to obtain solution B;

[0019] Take urea and deionized water, mix and stir evenly, add ferrosoferric oxide powder and hexadecyltrimethylammonium bromide, ultrasonically disperse for 1-1.2 hours, add ammonium sulfate, stir evenly at 45-50°C, heat to 90-95°C, add solution B, condense and reflux to a pH of 2-2.5, let stand and cool after the reaction, collect the product by suction, wash and dry, grind and transfer to 540-550°C for calcination for 2-2.5 hours to obtain magnetic ATO powder.

[0020] In a more optimized solution, the foaming is carried out in an external magnetic field environment, the magnetic field strength of the external magnetic field is 0.5-1.5 T, the magnetic field holding time is 3-5 minutes, and the direction of the external magnetic field is horizontal.

[0021] In a more optimized solution, the concentration of solution B is 0.2 mol / L; the molar ratio of urea, tin tetrachloride and antimony trichloride is 10:1; and the molar ratio of tin tetrachloride to antimony trichloride is 12:1.

[0022] A more optimized solution is a polyurethane foam prepared according to any one of the above methods for preparing antistatic polyurethane foam based on graphene.

[0023] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0024] The invention discloses an antistatic polyurethane foam based on graphene and a preparation method thereof. In the scheme, components such as an antistatic agent, a surfactant, dibutyltin dilaurate, triethylenediamine, a foaming agent, 1,2-propylene glycol and glycerol, a polyether polyol, and an isocyanate are mixed and foamed to form a polyurethane foam. In order to improve the antistatic performance of the product, the present application introduces an antistatic agent in the scheme. In the prior art, ATO powder has excellent electrical conductivity and chemical stability, and is therefore a commonly used antistatic agent. However, since ATO is generally in powder form, it is easy to agglomerate in the polyurethane foam. The dispersibility is poor, and when it is used as an antistatic agent, a large amount needs to be added to form a conductive path, which is actually easy to affect the mechanical properties of the product; therefore, in order to solve this technical problem, the present application firstly treats the surface of ATO powder with a silane coupling agent KH-550 to obtain amino-modified ATO powder, and then loads it onto the surface of graphene. On the one hand, graphene can be used to improve the dispersion performance of ATO powder. On the other hand, the ATO powder and graphene in the scheme are compounded to form a conductive path. Its antistatic performance is far better than that of pure ATO powder, and the amount of ATO powder added is relatively small.

[0025] At the same time, in order to improve the flame retardant properties of the product, the solution is to graft flame retardant monomers on the surface of amino-modified ATO powder, introduce 4,4-diaminodiphenylmethane and dichlorophenyl phosphate components, and use the amino group and P-Cl bond reaction grafting to achieve improved flame retardant properties; it should be reminded here that the solution uses antistatic agents to achieve both antistatic and flame retardant effects, and no additional flame retardants are needed during subsequent foaming, which greatly reduces costs, and the product still has excellent flame retardant properties; this solution also avoids the impact of flame retardants on product performance.

[0026] The plan also proposed another optimization plan. When preparing ATO powder, tin tetrachloride and antimony trichloride are used to coat and deposit on the surface of ferroferric oxide to obtain magnetic ATO powder. At the same time, during the foaming process, the plan introduced a magnetic field. The direction of the magnetic field is horizontal and parallel to the foaming mold. Under the action of the magnetic field, the antistatic agents can continuously overlap with each other and form a conductive network to improve the antistatic performance of the product.

[0027] It should be emphasized here: In order to avoid the influence of the magnetic field on the comprehensive performance of the product, the magnetic field intensity in the solution is relatively small, at 0.5~1.5T, and the holding time is relatively short, at 3~5min. Under the condition of this parameter limitation, the mechanical properties of the product will not be greatly affected, but will be improved; however, if the magnetic field intensity is larger or the holding time is longer, it will affect the mechanical properties and antistatic properties of the product.

[0028] The invention discloses an antistatic polyurethane foam based on graphene and a preparation method thereof. The process design is reasonable and the component ratio is appropriate. The prepared polyurethane foam has excellent antistatic performance and flame retardant performance, and the mechanical properties of the product are also improved. The polyurethane foam can be widely applied to multiple fields and has high practicality. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In this embodiment, the ATO powder has a particle size of 7-10 nm and is purchased from Shanghai Huben New Material Technology Co., Ltd. The graphene oxide is prepared by the Hummers method; phenyl dichlorophosphate is purchased from Aladdin Reagent Co., Ltd., the polyether polyol is polyether polyol 4110; and the isocyanate is isocyanate (PM-200).

[0031] Example 1

[0032] A method for preparing an antistatic polyurethane foam based on graphene comprises the following steps:

[0033] S11: KH-550, anhydrous ethanol and deionized water were mixed and ultrasonically dispersed for 20 minutes to obtain solution A; the mass ratio of the anhydrous ethanol to the deionized water was 1:1, and the concentration of KH-550 in solution B was 0.12 g / mL.

[0034] Take ATO powder and deionized water, ultrasonically disperse for 50 minutes, add solution A, stir and react in a 50°C water bath for 9 hours, collect the product after the reaction, wash and dry to obtain amino-modified ATO powder; the mass ratio of the ATO powder to KH-550 is 1:8.

[0035] S12: Mix 4,4-diaminodiphenylmethane and triethylamine, add acetonitrile and stir to dissolve, add acetonitrile solution of dichlorophenyl phosphate (concentration of 0.5 mol / L), stir for 20 minutes, then add amino-modified ATO powder, heat to 70°C in a nitrogen environment, keep warm for 8 hours, remove the solvent after the reaction, wash, and dry to obtain flame-retardant ATO powder. The molar ratio of dichlorophenyl phosphate, 4,4-diaminodiphenylmethane, and amino-modified ATO powder is 8:5:2; the molar ratio of triethylamine and 4,4-diaminodiphenylmethane is 1.2:1.

[0036] S13: Take graphene oxide and N,N-dimethylformamide solution, ultrasonically disperse for 20 minutes to obtain a graphene dispersion, add flame-retardant ATO powder, adjust the pH to 9 with sodium hydroxide, stir and react in a water bath at 80°C for 24 hours, add hydrazine hydrate, and continue the reaction for 7 hours. After the reaction is completed, collect the product by centrifugation, wash to neutrality, and dry to obtain an antistatic agent; the concentration of the graphene dispersion is 8 g / L, and the mass ratio of the graphene oxide to the flame-retardant ATO powder is 2:3.

[0037] S2: Take antistatic agent, surfactant, dibutyltin dilaurate, triethylenediamine, foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 20 minutes, add isocyanate, stir for 30 seconds, inject into the mold for foaming, and mature at 60°C for 12 hours to obtain the finished polyurethane foam.

[0038] The content of each component is: by weight, 100 parts of polyether polyol, 105 parts of isocyanate, 16 parts of antistatic agent, 1.3 parts of surfactant, 0.25 parts of dibutyltin dilaurate, 0.6 parts of triethylenediamine, 3.5 parts of foaming agent, 1.2 parts of 1,2-propylene glycol, and 1.2 parts of glycerol. The foaming agent is deionized water; the surfactant is fatty acid glyceride.

[0039] Example 2

[0040] A method for preparing an antistatic polyurethane foam based on graphene comprises the following steps:

[0041] S11: KH-550, anhydrous ethanol and deionized water were mixed and ultrasonically dispersed for 25 minutes to obtain solution A; the mass ratio of the anhydrous ethanol to the deionized water was 1:1, and the concentration of KH-550 in solution B was 0.12 g / mL.

[0042] Take ATO powder and deionized water, ultrasonically disperse for 55 minutes, add solution A, stir and react in a 55°C water bath for 8.5 hours, collect the product after the reaction, wash and dry to obtain amino-modified ATO powder; the mass ratio of the ATO powder to KH-550 is 1:8.

[0043] S12: Mix 4,4-diaminodiphenylmethane and triethylamine, add acetonitrile and stir to dissolve, add acetonitrile solution of dichlorophenyl phosphate (concentration of 0.5 mol / L), stir for 25 minutes, then add amino-modified ATO powder, heat to 75°C under nitrogen environment, keep warm for 7 hours, remove solvent after the reaction, wash, and dry to obtain flame-retardant ATO powder. The molar ratio of dichlorophenyl phosphate, 4,4-diaminodiphenylmethane, and amino-modified ATO powder is 8:5:2; the molar ratio of triethylamine and 4,4-diaminodiphenylmethane is 1.2:1.

[0044] S13: Take graphene oxide and N,N-dimethylformamide solution, ultrasonically disperse for 25 minutes to obtain a graphene dispersion, add flame-retardant ATO powder, adjust the pH to 9 with sodium hydroxide, stir and react for 22 hours in a water bath at 85°C, add hydrazine hydrate, and continue the reaction for 7.5 hours. After the reaction is completed, collect the product by centrifugation, wash to neutrality, and dry to obtain an antistatic agent; the concentration of the graphene dispersion is 8 g / L, and the mass ratio of the graphene oxide and the flame-retardant ATO powder is 2:3.

[0045] S2: Take antistatic agent, surfactant, dibutyltin dilaurate, triethylenediamine, foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 25 minutes, add isocyanate, stir for 35 seconds, inject into the mold for foaming, and mature at 65°C for 11 hours to obtain the finished polyurethane foam.

[0046] The content of each component is: by weight, 100 parts of polyether polyol, 105 parts of isocyanate, 16 parts of antistatic agent, 1.3 parts of surfactant, 0.25 parts of dibutyltin dilaurate, 0.6 parts of triethylenediamine, 3.5 parts of foaming agent, 1.2 parts of 1,2-propylene glycol, and 1.2 parts of glycerol. The foaming agent is deionized water; the surfactant is fatty acid glyceride.

[0047] Example 3

[0048] A method for preparing an antistatic polyurethane foam based on graphene comprises the following steps:

[0049] S11: KH-550, anhydrous ethanol and deionized water were mixed and ultrasonically dispersed for 30 minutes to obtain solution A; the mass ratio of the anhydrous ethanol to the deionized water was 1:1, and the concentration of KH-550 in solution B was 0.12 g / mL.

[0050] Take ATO powder and deionized water, ultrasonically disperse for 60 minutes, add solution A, stir and react in a 55°C water bath for 8 hours, collect the product after the reaction, wash and dry to obtain amino-modified ATO powder; the mass ratio of the ATO powder to KH-550 is 1:8.

[0051] S12: Mix 4,4-diaminodiphenylmethane and triethylamine, add acetonitrile and stir to dissolve, add acetonitrile solution of dichlorophenyl phosphate (concentration of 0.5 mol / L), stir for 30 minutes, then add amino-modified ATO powder, heat to 75°C under nitrogen environment, keep warm for 6 hours, remove solvent after the reaction, wash, and dry to obtain flame-retardant ATO powder. The molar ratio of dichlorophenyl phosphate, 4,4-diaminodiphenylmethane, and amino-modified ATO powder is 8:5:2; the molar ratio of triethylamine and 4,4-diaminodiphenylmethane is 1.2:1.

[0052] S13: Take graphene oxide and N,N-dimethylformamide solution, ultrasonically disperse for 30 minutes to obtain a graphene dispersion, add flame-retardant ATO powder, adjust the pH to 9 with sodium hydroxide, stir and react in a water bath at 85°C for 24 hours, add hydrazine hydrate, and continue to react for 8 hours. After the reaction is completed, collect the product by centrifugation, wash to neutrality, and dry to obtain an antistatic agent; the concentration of the graphene dispersion is 8 g / L, and the mass ratio of the graphene oxide to the flame-retardant ATO powder is 2:3.

[0053] S2: Take antistatic agent, surfactant, dibutyltin dilaurate, triethylenediamine, foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 30 minutes, add isocyanate, stir for 40 seconds, inject into the mold for foaming, and mature at 65°C for 10 hours to obtain the finished polyurethane foam.

[0054] The content of each component is: by weight, 100 parts of polyether polyol, 105 parts of isocyanate, 16 parts of antistatic agent, 1.3 parts of surfactant, 0.25 parts of dibutyltin dilaurate, 0.6 parts of triethylenediamine, 3.5 parts of foaming agent, 1.2 parts of 1,2-propylene glycol, and 1.2 parts of glycerol. The foaming agent is deionized water; the surfactant is fatty acid glyceride.

[0055] Example 4: Compared with Example 2, Example 4 differs in that ATO powder is replaced by magnetic ATO powder.

[0056] A method for preparing an antistatic polyurethane foam based on graphene comprises the following steps:

[0057] S11: Take acrylic acid, deionized water and anhydrous ethanol, mix and stir evenly, add tin tetrachloride and antimony trichloride, and ultrasonically disperse for 25 minutes to obtain solution B; the volume ratio of acrylic acid, deionized water and anhydrous ethanol is 7:3:3, and the concentration of solution B is 0.2 mol / L; the molar ratio of tin tetrachloride and antimony trichloride is 12:1.

[0058] Take urea and deionized water, mix and stir evenly, add ferroferric oxide powder and hexadecyltrimethylammonium bromide, ultrasonically disperse for 1.2 hours, add ammonium sulfate, stir evenly at 45°C, heat to 90°C, add solution B, condense and reflux until the pH is 2, let stand and cool after the reaction, collect the product by suction filtration, wash and dry, grind and transfer to calcine at 550°C, the calcination time is 2.5 hours, and obtain magnetic ATO powder. The molar ratio of urea, tin tetrachloride and antimony trichloride is 10:1; the amount of CTAB is 0.07wt% of the ferroferric oxide powder; the molar ratio of sulfate to chloride ion in the system is 1:25.

[0059] S12: KH-550, anhydrous ethanol and deionized water were mixed and ultrasonically dispersed for 25 minutes to obtain solution A; the mass ratio of the anhydrous ethanol to the deionized water was 1:1, and the concentration of KH-550 in solution B was 0.12 g / mL.

[0060] Take ATO powder and deionized water, ultrasonically disperse for 55 minutes, add solution A, stir and react in a 55°C water bath for 8.5 hours, collect the product after the reaction, wash and dry to obtain amino-modified ATO powder; the mass ratio of the ATO powder to KH-550 is 1:8.

[0061] S13: Mix 4,4-diaminodiphenylmethane and triethylamine, add acetonitrile and stir to dissolve, add acetonitrile solution of dichlorophenyl phosphate (concentration of 0.5 mol / L), stir for 25 minutes, then add amino-modified ATO powder, heat to 75°C under nitrogen environment, keep warm for 7 hours, remove solvent after the reaction, wash, and dry to obtain flame-retardant ATO powder. The molar ratio of dichlorophenyl phosphate, 4,4-diaminodiphenylmethane, and amino-modified ATO powder is 8:5:2; the molar ratio of triethylamine and 4,4-diaminodiphenylmethane is 1.2:1.

[0062] S14: Take graphene oxide and N,N-dimethylformamide solution, ultrasonically disperse for 25 minutes to obtain a graphene dispersion, add flame-retardant ATO powder, adjust the pH to 9 with sodium hydroxide, stir and react in a water bath at 85°C for 22 hours, add hydrazine hydrate, and continue to react for 7.5 hours. After the reaction is completed, collect the product by centrifugation, wash to neutrality, and dry to obtain an antistatic agent; the concentration of the graphene dispersion is 8 g / L, and the mass ratio of the graphene oxide and the flame-retardant ATO powder is 2:3.

[0063] S2: Take antistatic agent, surfactant, dibutyltin dilaurate, triethylenediamine, foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 25 minutes, add isocyanate, stir for 35 seconds, inject into the mold for foaming, and ripen at 65°C for 11 hours to obtain a polyurethane foam product. The foaming is carried out under an external magnetic field environment, the magnetic field strength of the external magnetic field is 1T, the magnetic field holding time is 4 minutes, and the direction of the external magnetic field is horizontal.

[0064] The content of each component is: by weight, 100 parts of polyether polyol, 105 parts of isocyanate, 16 parts of antistatic agent, 1.3 parts of surfactant, 0.25 parts of dibutyltin dilaurate, 0.6 parts of triethylenediamine, 3.5 parts of foaming agent, 1.2 parts of 1,2-propylene glycol, and 1.2 parts of glycerol. The foaming agent is deionized water; the surfactant is fatty acid glyceride.

[0065] Comparative Example 1: Compared with Example 2, Comparative Example 1 differs in that the surface of the ATO powder is not subjected to surface flame retardancy.

[0066] A method for preparing an antistatic polyurethane foam based on graphene comprises the following steps:

[0067] S11: KH-550, anhydrous ethanol and deionized water were mixed and ultrasonically dispersed for 25 minutes to obtain solution A; the mass ratio of the anhydrous ethanol to the deionized water was 1:1, and the concentration of KH-550 in solution B was 0.12 g / mL.

[0068] Take ATO powder and deionized water, ultrasonically disperse for 55 minutes, add solution A, stir and react in a 55°C water bath for 8.5 hours, collect the product after the reaction, wash and dry to obtain amino-modified ATO powder; the mass ratio of the ATO powder to KH-550 is 1:8.

[0069] S12: Take graphene oxide and N,N-dimethylformamide solution, ultrasonically disperse for 25 minutes to obtain a graphene dispersion, add amino-modified ATO powder, adjust the pH to 9 with sodium hydroxide, stir and react in a water bath at 85°C for 22 hours, add hydrazine hydrate, and continue the reaction for 7.5 hours. After the reaction is completed, collect the product by centrifugation, wash to neutrality, and dry to obtain an antistatic agent; the concentration of the graphene dispersion is 8 g / L, and the mass ratio of the graphene oxide and the amino-modified ATO powder is 2:3.

[0070] S2: Take antistatic agent, surfactant, dibutyltin dilaurate, triethylenediamine, foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 25 minutes, add isocyanate, stir for 35 seconds, inject into the mold for foaming, and mature at 65°C for 11 hours to obtain the finished polyurethane foam.

[0071] The content of each component is: by weight, 100 parts of polyether polyol, 105 parts of isocyanate, 16 parts of antistatic agent, 1.3 parts of surfactant, 0.25 parts of dibutyltin dilaurate, 0.6 parts of triethylenediamine, 3.5 parts of foaming agent, 1.2 parts of 1,2-propylene glycol, and 1.2 parts of glycerol. The foaming agent is deionized water; the surfactant is fatty acid glyceride.

[0072] Comparative Example 2: Compared with Example 2, Comparative Example 2 differs in that ATO powder is directly mixed with graphene.

[0073] A method for preparing an antistatic polyurethane foam based on graphene comprises the following steps:

[0074] S1: Take graphene oxide and N,N-dimethylformamide solution, ultrasonically disperse for 25 minutes to obtain a graphene dispersion, add ATO powder, adjust the pH to 9 with sodium hydroxide, stir and react in a water bath at 85°C for 22 hours, add hydrazine hydrate, and continue to react for 7.5 hours. After the reaction is completed, collect the product by centrifugation, wash to neutrality, and dry to obtain an antistatic agent; the concentration of the graphene dispersion is 8 g / L, and the mass ratio of the graphene oxide to the ATO powder is 2:3.

[0075] S2: Take antistatic agent, surfactant, dibutyltin dilaurate, triethylenediamine, foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 25 minutes, add isocyanate, stir for 35 seconds, inject into the mold for foaming, and mature at 65°C for 11 hours to obtain the finished polyurethane foam.

[0076] The content of each component is: by weight, 100 parts of polyether polyol, 105 parts of isocyanate, 16 parts of antistatic agent, 1.3 parts of surfactant, 0.25 parts of dibutyltin dilaurate, 0.6 parts of triethylenediamine, 3.5 parts of foaming agent, 1.2 parts of 1,2-propylene glycol, and 1.2 parts of glycerol. The foaming agent is deionized water; the surfactant is fatty acid glyceride.

[0077] Comparative Example 3: Compared with Example 2, Comparative Example 3 differs in that only flame retardant ATO powder is added.

[0078] A method for preparing an antistatic polyurethane foam based on graphene comprises the following steps:

[0079] S11: KH-550, anhydrous ethanol and deionized water were mixed and ultrasonically dispersed for 25 minutes to obtain solution A; the mass ratio of the anhydrous ethanol to the deionized water was 1:1, and the concentration of KH-550 in solution B was 0.12 g / mL.

[0080] Take ATO powder and deionized water, ultrasonically disperse for 55 minutes, add solution A, stir and react in a 55°C water bath for 8.5 hours, collect the product after the reaction, wash and dry to obtain amino-modified ATO powder; the mass ratio of the ATO powder to KH-550 is 1:8.

[0081] S12: Mix 4,4-diaminodiphenylmethane and triethylamine, add acetonitrile and stir to dissolve, add acetonitrile solution of dichlorophenyl phosphate (concentration of 0.5 mol / L), stir for 25 minutes, then add amino-modified ATO powder, heat to 75°C under nitrogen environment, keep warm for 7 hours, remove solvent after the reaction, wash, and dry to obtain flame-retardant ATO powder. The molar ratio of dichlorophenyl phosphate, 4,4-diaminodiphenylmethane, and amino-modified ATO powder is 8:5:2; the molar ratio of triethylamine and 4,4-diaminodiphenylmethane is 1.2:1.

[0082] S2: Take flame retardant ATO powder, surfactant, dibutyltin dilaurate, triethylenediamine, foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 25 minutes, add isocyanate, stir for 35 seconds, inject into the mold for foaming, and mature at 65°C for 11 hours to obtain a polyurethane foam product.

[0083] The content of each component is: by weight, 100 parts of polyether polyol, 105 parts of isocyanate, 26 parts of flame retardant ATO powder, 1.3 parts of surfactant, 0.25 parts of dibutyltin dilaurate, 0.6 parts of triethylenediamine, 3.5 parts of foaming agent, 1.2 parts of 1,2-propylene glycol, and 1.2 parts of glycerol. The foaming agent is deionized water; the surfactant is fatty acid glyceride.

[0084] Comparative Example 4: Compared with Example 4, Comparative Example 4 differs in that the magnetic field intensity is 5T.

[0085] Detection experiment:

[0086] The polyurethane foams prepared in Examples 1-4 and Comparative Examples 1-3 were cut and polished into samples of 80 mm×10 mm×10 mm in size, and the following tests were performed:

[0087] 1. Test the limiting oxygen index of the sample according to the method disclosed in GB / T2406-1993 "Plastic Combustion Performance Test Method Oxygen Index Method".

[0088] 2. Test the volume resistivity according to the test standard published in GB / T2439-2001.

[0089]

[0090] Conclusion: The present invention discloses an antistatic polyurethane foam based on graphene and a preparation method thereof. The process design is reasonable and the component ratio is appropriate. The prepared polyurethane foam has excellent antistatic performance and excellent flame retardant performance, and the mechanical properties of the product are also improved. It can be widely used in multiple fields and has high practicality.

[0091] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing an antistatic polyurethane foam based on graphene, characterized in that: The following steps are involved: S1: Take graphene oxide and N,N-dimethylformamide solution, ultrasonically disperse to obtain graphene dispersion, add flame retardant ATO powder, adjust pH to 9-10 with sodium hydroxide, stir and react in a water bath at 80-85°C for 20-24h, add hydrazine hydrate, continue to react for 7-8h, collect the product by centrifugation after the reaction is completed, wash to neutral, and dry to obtain an antistatic agent; S2: Take an antistatic agent, a surfactant, dibutyltin dilaurate, triethylenediamine, a foaming agent, 1,2-propylene glycol and propylene glycol, mix and stir evenly, add polyether polyol, continue stirring for 20-30 minutes, add isocyanate, stir for 30-40 seconds, inject into a mold for foaming, and ripen at 60-65°C for 10-12 hours to obtain a polyurethane foam product; In step S1, the specific preparation steps of the flame retardant ATO powder are: S11: Mix KH-550, anhydrous ethanol and deionized water, and disperse by ultrasonic to obtain solution A; Take ATO powder and deionized water, disperse them by ultrasonic, add solution A, stir and react in a water bath at 50-55°C for 8-9 hours, collect the product after the reaction, wash and dry it to obtain amino-modified ATO powder; S12: Mix 4,4-diaminodiphenylmethane and triethylamine, add acetonitrile and stir to dissolve, then add acetonitrile solution of phenyl dichlorophosphate, stir for 20-30 minutes, add amino-modified ATO powder, heat to 70-75°C under nitrogen environment, keep warm for 6-8 hours, remove the solvent after the reaction, wash and dry to obtain flame-retardant ATO powder.

2. The method for preparing a graphene-based antistatic polyurethane foam according to claim 1, characterized in that: In step S2, the content of each component is: by weight, 100-105 parts of polyether polyol, 105-110 parts of isocyanate, 15-20 parts of antistatic agent, 1-1.5 parts of surfactant, 0.2-0.3 parts of dibutyltin dilaurate, 0.5-0.8 parts of triethylenediamine, 3-4 parts of foaming agent, 1-1.2 parts of 1,2-propylene glycol, and 1-1.2 parts of glycerol.

3. The method for preparing a graphene-based antistatic polyurethane foam according to claim 1, characterized in that: In step S2, the foaming agent is deionized water; the surfactant is fatty acid glyceride; in step S1, the concentration of the graphene dispersion is 8-10 g / L, and the mass ratio of the graphene oxide to the flame-retardant ATO powder is 2:

3.

4. The method for preparing a graphene-based antistatic polyurethane foam according to claim 1, characterized in that: In step S12, the molar ratio of phenyl dichlorophosphate, 4,4-diaminodiphenylmethane, and amino-modified ATO powder is 8:5:2; the molar ratio of triethylamine and 4,4-diaminodiphenylmethane is 1.2:

1.

5. The method for preparing a graphene-based antistatic polyurethane foam according to claim 1, characterized in that: The ATO powder is magnetic ATO powder, and the preparation steps of the magnetic ATO powder are: Take acrylic acid, deionized water and anhydrous ethanol, mix and stir evenly, add tin tetrachloride and antimony trichloride, and disperse by ultrasonic to obtain solution B; Take urea and deionized water, mix and stir evenly, add ferrosoferric oxide powder and hexadecyltrimethylammonium bromide, ultrasonically disperse for 1-1.2 hours, add ammonium sulfate, stir evenly at 45-50°C, heat to 90-95°C, add solution B, condense and reflux to a pH of 2-2.5, let stand and cool after the reaction, collect the product by suction, wash and dry, grind and transfer to 540-550°C for calcination for 2-2.5 hours to obtain magnetic ATO powder.

6. The method for preparing a graphene-based antistatic polyurethane foam according to claim 5, characterized in that: The foaming is carried out under an external magnetic field environment, the magnetic field strength of the external magnetic field is 0.5-1.5 T, the magnetic field holding time is 3-5 minutes, and the direction of the external magnetic field is horizontal.

7. The method for preparing a graphene-based antistatic polyurethane foam according to claim 5, characterized in that: The concentration of the solution B is 0.2 mol / L; the molar ratio of the urea, tin tetrachloride and antimony trichloride is 10:1; and the molar ratio of tin tetrachloride to antimony trichloride is 12:

1.

8. A polyurethane foam prepared according to the method for preparing an antistatic polyurethane foam based on graphene according to any one of claims 1 to 7.

Images