Antistatic inorganic nano-hybrid waterborne polyurethane as well as preparation method and application thereof

Abstract

The invention relates to antistatic inorganic nano-hybrid waterborne polyurethane as well as a preparation method and application thereof, aiming at different hardness degrees of two surfaces of a bonded base material, two polyols with different glass transition temperatures are used for synthesizing a polyurethane prepolymer. Meanwhile, nano silicon dioxide or coupling agent modified nano silicon dioxide is introduced, so that the bonding force of the waterborne polyurethane is improved, and particularly, the bonding effect at high temperature is improved. In addition, the inorganic electrostatic agent is added into the system, and the waterborne polyurethane adhesive is endowed with antistatic performance, so that the adverse effect of static electricity on the production process is eliminated. The nano silicon dioxide or coupling agent modified nano silicon dioxide and the inorganic antistatic agent are synergistically used, so that the inorganic antistatic agent can be stably dispersed in a water gel system for a long time, and a better antistatic effect is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of adhesives, and relates to an antistatic inorganic nano-hybrid waterborne polyurethane, a preparation method thereof and an application thereof. Background Art

[0002] In the field of automotive interiors, solvent-based polyurethanes have always occupied the main market due to their strong initial adhesion and fast drying. In recent years, with the increasing awareness of environmental protection among people, the automotive industry has become increasingly strict with the requirements for VOCs. Compared with traditional solvent-based polyurethane adhesives, waterborne polyurethane automotive interior covering adhesives with low VOCs show a trend of gradually replacing solvent-based polyurethane automotive interior covering adhesives. However, the bonding performance of waterborne covering adhesives has decreased compared with similar solvent-based products, so some methods need to be adopted for improvement.

[0003] On the other hand, static electricity causes a large amount of dust to be adsorbed on automotive interiors. Even after wiping, the dust will quickly re-adsorb, and the sparks generated by static electricity are the main cause of explosion accidents in automobiles. Therefore, there is a high demand for the antistatic effect of materials in the field of automotive interiors. Among them, inorganic antistatic agents can always play a role during the service life of automobiles and are very suitable for use in automotive interior materials. By introducing inorganic antistatic agents into the waterborne polyurethane system, the antistatic performance of automotive interior covering adhesives can be imparted to eliminate the adverse effects of static electricity on the production process. Compared with organic antistatic agents, inorganic antistatic agents have better long-term effectiveness. However, in the waterborne adhesive system, the stability of inorganic antistatic agents is very poor, and they lack compatibility with the system, and are prone to precipitation and sedimentation, thus affecting the stability of waterborne adhesive products and the antistatic effect. The present invention can enable the antistatic agent to be stably dispersed in the water-based glue for a long time and have a better antistatic effect by introducing hydrophilic nano-silica so that the inorganic antistatic agent can play a synergistic role in the system. Summary of the Invention

[0004] Aiming at the defects of the prior art, the technical problem to be solved by the present invention is the problem that the inorganic antistatic agent is incompatible with the waterborne polyurethane adhesive system and the inorganic antistatic agent is prone to sedimentation.

[0005] To achieve the above technical objectives, the technical solutions adopted by the present invention are as follows: In a first aspect, an antistatic inorganic nano-hybrid waterborne polyurethane composition includes: a polyurethane prepolymer and nano-stannous oxide, and any one of nano-silica or amino-coupling agent-modified nano-silica; wherein, the nano-stannous oxide is selected from stannous oxide particles or a stannous oxide aqueous dispersion, and the average particle size of the stannous oxide does not exceed 100 nm; The nano-silica is selected from silica particles or silica aqueous dispersions, and the average particle size of the silica does not exceed 100 nm; The polyurethane prepolymer contains a hydrophilic chain extender, polyols with at least two different glass transition temperatures. At the same time, the polyurethane prepolymer is capped with -NCO groups, and the hydrophilic chain extender is a polyol or polyamine containing at least one -COOH or -SO3H group.

[0006] Furthermore, the amino group-containing coupling agent-modified nano-silica comprises the following raw materials in parts by weight: 15 - 30 parts of an amino group-containing silane coupling agent, 5 - 15 parts of methyl orthosilicate or ethyl orthosilicate, 1 - 20 parts of water, 50 - 70 parts of an alcohol solvent, and 0.001 - 0.01 parts of a catalyst; Among them, the amino group-containing silane coupling agent is selected from any one or more of: 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, N-aminoethyl-3-aminopropyltrimethoxysilane, or N-aminoethyl-3-aminopropylmethyldimethoxysilane; Preferably, the alcohol solvent is selected from any one or more of: methanol, ethanol, or isopropanol; Preferably, the catalyst is selected from any one or more of: tetrabutyl titanate or dibutyltin dilaurate;

[0007] Preferably, the amino group-containing coupling agent-modified nano-silica is synthesized by the sol-gel method.

[0008] Furthermore, the polyurethane prepolymer comprises the following raw materials in parts by weight: 68 - 72 parts of polyol, 23 - 24 parts of diisocyanate, 4 - 7 parts of hydrophilic chain extender, 2 - 4 parts of polyol chain extender, 1 - 2 parts of neutralizer, and 0.001 - 0.01 parts of catalyst.

[0009] Among them, the number-average molecular weight range of the polyol is 200 - 4000; preferably, the number-average molecular weight range of the polyol is 600 - 4000; The polyol is selected from one or two of: polyester polyol or polyether polyol; The polyester polyol is selected from one or more of: adipic acid-based polyester polyol, phthalic acid-based polyester polyol, aliphatic polyester polyol, or polycaprolactone polyol; The polyether polyol is selected from one or more of: polytetrahydrofuran ether diol, polypropylene glycol; Preferably, the polyol is selected from at least two of: polybutylene adipate diol, polyisopropyl adipate, neopentyl glycol adipate diol, polytetrahydrofuran ether diol, polypropylene glycol.

[0010] The diisocyanate is selected from one or more of isophorone diisocyanate, diphenylmethane diisocyanate, toluene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and 1,6-hexamethylene diisocyanate; The diisocyanate is preferably isophorone diisocyanate or diphenylmethane diisocyanate.

[0011] The hydrophilic chain extender is selected from at least one of dimethylolbutanoic acid (DMBA), dimethylolpropionic acid (DMPA), and sodium 2-(2-aminoethylamino)ethanesulfonate (A95). Preferably, the hydrophilic chain extender is dimethylolpropionic acid.

[0012] The polyol chain extender is selected from one or more of 1,4-butanediol, 1,6-hexanediol, and 1,3-butanediol; The neutralizing agent is selected from one or more of triethylamine, triethanolamine, and N,N-dimethylethanolamine.

[0013] The catalyst is selected from any one or more of organobismuth catalysts and organotin catalysts; Preferably, the catalyst is selected from dibutyltin dilaurate (DBTDL).

[0014] Furthermore, the method for preparing the polyurethane prepolymer includes: S1. Mix the polyol, diisocyanate, and hydrophilic chain extender together for reaction, then add the polyol chain extender for reaction, and then add the catalyst for reaction until the -NCO content of the reaction mixture is ≤ 10 wt%; S2. Neutralization reaction: Cool the polyurethane prepolymer to 30 - 60 °C, and add the neutralizing agent under the shearing action of a high-speed disperser for reaction for 5 - 60 min.

[0015] Preferably, in step S1, acetone with a weight 1 - 2 times that of the total weight of the hydrophilic chain extender is added during the mixing of the polyol, diisocyanate, and hydrophilic chain extender; Preferably, after cooling in step S2, first add acetone with a weight of 40 - 60 wt% of the polyurethane prepolymer to reduce the viscosity of the polyurethane prepolymer, and then add the neutralizing agent for neutralization reaction under the shearing action of a high-speed disperser.

[0016] Preferably, the method for preparing the polyurethane prepolymer further includes: S3. A ketone removal process, set the temperature at 40 - 60 °C, the pressure in the container does not exceed 0.1 Pa, and remove acetone by vacuum.

[0017] Second aspect, a preparation method of the above-mentioned antistatic inorganic nano-hybrid waterborne polyurethane composition, comprising: mixing a polyurethane prepolymer, nano stannous oxide, nano silica or amino-coupling-agent-modified nano silica, and then dispersing them evenly by mechanical means.

[0018] Preferably, the mechanical means is specifically: using a high-speed disperser to disperse at a rotation speed of 500 - 5000 rpm; Preferably, the dispersion time is 5 - 60 min; more preferably, the dispersion time is 30 min.

[0019] Third aspect, use of the above-mentioned antistatic inorganic nano-hybrid waterborne polyurethane composition for bonding between a polyurethane substrate and a plastic substrate.

[0020] Wherein, the plastic substrate includes any one of polybutylene terephthalate (PBT), polycarbonate (PC), polyamide (PA), acrylonitrile-butadiene-styrene copolymer (ABS) and polyphenylene sulfide (PPS).

[0021] Fourth aspect, use of the above-mentioned antistatic inorganic nano-hybrid waterborne polyurethane composition as an automotive interior covering adhesive.

[0022] The beneficial effects of the present invention are as follows: First, aiming at the different hardness levels of the two sides of the substrate to be bonded, polyols with two different glass transition temperatures are designed and used to synthesize the polyurethane prepolymer. Second, nano silica or coupling-agent-modified nano silica is introduced to increase the adhesion of the waterborne polyurethane to different substrates, especially to improve the bonding effect at high temperatures and avoid bonding failure or cohesive failure. Finally, an inorganic antistatic agent is continuously added to the system to endow the waterborne polyurethane adhesive with long-term antistatic performance. Compared with organic antistatic agents, inorganic antistatic agents have better long-term effectiveness. However, in the waterborne adhesive system, inorganic antistatic agents are prone to sedimentation, affecting the stability of the product. In the present invention, nano silica or coupling-agent-modified nano silica and the inorganic antistatic agent are used synergistically. Nano silica or coupling-agent-modified nano silica forms a hydrogen bond network with the polyurethane prepolymer, enabling the inorganic antistatic agent to be stably dispersed in the water-based adhesive system for a long time and having a better antistatic effect. Specific embodiments

[0023] The following combines specific embodiments to further elaborate the present invention. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0024] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] If the specific experimental conditions are not specified in the examples, they are usually in accordance with the conventional conditions in the art or the conditions recommended by the reagent company; the materials, reagents, etc. used in the examples, unless otherwise specified, can be obtained through commercial channels.

[0026] Example 1 Synthesis of amino-coupling agent modified nano-silica by sol-gel method: Add 22.5 parts of 3-aminopropylmethyldiethoxysilane and 7.5 parts of tetraethyl orthosilicate to 70 parts of a mixed solvent of water / ethanol, where the weight ratio of water / ethanol is 1:6. Then add 0.005 parts of dibutyltin dilaurate (DBTDL) catalyst, heat up to 50 °C, stir and react for 2 h until the solution is clear and transparent, and then let it stand for 1 h to obtain the amino-coupling agent modified nano-silica solution.

[0027] Example 2 Synthesis of amino-coupling agent modified nano-silica by sol-gel method: Add 24 parts of N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane and 6 parts of tetraethyl orthosilicate to 70 parts of a mixed solvent of water / ethanol, where the weight ratio of water / ethanol is 1:13. Then add 0.005 parts of DBTDL catalyst, heat up to 50 °C, stir and react for 2 h until the solution is clear and transparent, and then let it stand for 1 h to obtain the amino-coupling agent modified nano-silica solution.

[0028] Example 3 Waterborne polyurethane is synthesized according to the following steps (where each raw material is in parts by weight): S1. Preparation of polyurethane prepolymer containing hydrophilic monomer: Add two polyols in a three-necked flask: 15 parts of neopentyl glycol adipate diol and 125 parts of butanediol adipate diol. Vacuum dehydrate the polyols at 120 °C for 2 h, cool down to 80 - 85 °C, add 4 parts of dimethylolpropionic acid and 6 parts of acetone, stir for 20 min, add 45 parts of isophorone diisocyanate, and react at 80 - 85 °C for 2 h. Then add 6 parts of 1,4-butanediol and react at 80 - 85 °C for 1 h. Then add 0.001 parts of catalyst DBTDL and react at 70 - 80 °C until the content of -NCO is reduced to 5 wt%, thus obtaining the polyurethane prepolymer containing hydrophilic monomer. S2. Neutralization reaction: Cool the polyurethane prepolymer to 40 - 45 °C, add 82 parts of acetone to reduce the viscosity of the polyurethane prepolymer, and then, under the shearing action of a high-speed disperser, add 3 parts of triethylamine and react for 15 - 20 min; S3. Ketone removal process: Set the temperature at 55 °C and the pressure in the container at 0.098 Pa, and remove acetone by vacuum for 1 - 3 h until the acetone content is < 200 ppm, thereby obtaining an aqueous polyurethane automotive interior coating adhesive with a solid content of 50%; S4. Take 95 parts of the water-based glue prepared above, sequentially add 4 parts of 30% nano-silica sol (average particle size 15 nm) and 1 part of 30% stannous oxide sol (average particle size 10 nm), and disperse at 1000 rpm for 30 min with a high-speed disperser to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0029] Example 4 The synthesis steps of the aqueous polyurethane are the same as those in Example 3, except that in S4, take 95 parts of the water-based glue prepared above, sequentially add 4 parts of the amino-coupling agent-modified nano-silica solution prepared in Example 1 and 1 part of 30% stannous oxide sol (average particle size 10 nm), and disperse at 1000 rpm for 30 min with a high-speed disperser to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0030] Example 5 The synthesis steps of the aqueous polyurethane are the same as those in Example 3, except that in S4, take 95 parts of the water-based glue prepared above, sequentially add 4 parts of the amino-coupling agent-modified nano-silica solution prepared in Example 2 and 1 part of 30% stannous oxide sol (average particle size 10 nm), and disperse at 1000 rpm for 30 min with a high-speed disperser to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0031] Example 6 The aqueous polyurethane is synthesized according to the following steps (where each raw material is in parts by weight); S1. Preparation of a polyurethane prepolymer containing a hydrophilic monomer: Add two polyols in a three-necked flask: 130 parts of polybutylene adipate diol and 10 parts of polytetrahydrofuran ether diol. Vacuum dehydrate the polyols at 120 °C for 2 h, cool to 80 - 85 °C, add 5 parts of dimethylolpropionic acid and 4 parts of acetone, stir for 20 min, add 24 parts of diphenylmethane diisocyanate, and react at 80 - 85 °C for 2 h. Then add 4 parts of 1,4-butanediol and react at 80 - 85 °C for 1 h. Then add 0.002 parts of a catalyst and react at 70 - 80 °C until the -NCO content is reduced to 10 wt%, thereby obtaining a polyurethane prepolymer containing a hydrophilic monomer.

[0032] S2, Neutralization reaction: Cool the polyurethane prepolymer to 40 - 45 °C, add 76 parts of acetone to reduce the viscosity of the polyurethane prepolymer, and then add 4 parts of triethylamine under the shearing action of a high-speed disperser and react for 15 - 20 min.

[0033] S3, Ketone removal process: Set the temperature at 55 °C and the pressure at 0.098 Pa, remove ketone for 1 - 3 h, and the acetone content < 200 ppm to obtain an aqueous polyurethane adhesive with a solid content of 50%.

[0034] S4, Take 90 parts of the water-based glue prepared above, sequentially add 8 parts of 30% nano-silica sol (average particle size 15 nm) and 2 parts of 30% stannous oxide sol (average particle size 10 nm), and disperse at 1000 rpm for 30 min with a high-speed disperser to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0035] Example 7 The synthesis steps of the aqueous polyurethane are the same as those in Example 6, except that in S4, take 90 parts of the water-based glue prepared above, sequentially add 8 parts of the amino-coupling agent-modified nano-silica solution prepared in Example 1 and 2 parts of 30% stannous oxide sol (particle size 10 nm), and disperse at 1000 rpm for 30 min with a high-speed disperser to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0036] Example 8 The synthesis steps of the aqueous polyurethane are the same as those in Example 6, except that in S4, take 90 parts of the water-based glue prepared above, sequentially add 8 parts of the amino-coupling agent-modified nano-silica solution prepared in Example 1 and 2 parts of 30% stannous oxide sol (average particle size 10 nm), and disperse at 1000 rpm for 30 min with a high-speed disperser to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0037] Comparative Example 1 The synthesis steps of the aqueous polyurethane are the same as those in Example 3, except that in S4, take 100 parts of the water-based glue prepared above and directly disperse at 1000 rpm for 30 min with a high-speed disperser to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0038] Comparative Example 2 The synthesis steps of the aqueous polyurethane are the same as those in Example 6, except that in S4, take 98 parts of the water-based glue prepared above, add 2 parts of 30% stannous oxide sol (average particle size 10 nm), and disperse at 1000 rpm for 30 min with a high-speed disperser to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0039] Comparative Example 3 The synthesis steps of the aqueous polyurethane are the same as those in Example 6, except that in S4, 92 parts of the water-based glue prepared above are taken, and 8 parts of the amino-coupling agent-modified nano-silica solution prepared in Example 1 are added, and dispersed at a speed of 1000 rpm by a high-speed disperser for 30 min to obtain antistatic inorganic nano-hybrid aqueous polyurethane.

[0040] Testing part: The properties of the aqueous polyurethane adhesive samples prepared in Examples 3-8 and Comparative Examples 1 and 2 were tested, and the test results are listed in Table 1.

[0041] Sample preparation: The prepared aqueous polyurethane adhesive sample was evenly brushed on the surface of a 10 cm × 10 cm polyurethane (PU) leather, with a wet film thickness of 15-20 μm, and baked at 80 °C for 30 min to obtain a PU rubber sheet sample to be tested with a dry film thickness of the adhesive layer of 5-10 μm. An adhesive layer less than 5 microns will result in insufficient adhesion, and too thick an adhesive layer will also cause defects such as bubbles, which will affect the adhesion.

[0042] Bonding strength: Referring to the standard of ISO 29863:2018, the above-mentioned PU rubber sheet sample was bonded to an acrylonitrile-butadiene-styrene copolymer (ABS) test piece. After maintaining the bonding pressure for 20 min, static shear tests were carried out at room temperature and 80 °C, and the shear test time was recorded. The longer the test time, the better the bonding strength of the adhesive.

[0043] Antistatic performance: Referring to the standard of GB / T 1410-2006, the surface resistance of the PU rubber sheet surface was measured with a surface resistance meter.

[0044] Stability test of aqueous polyurethane: The aqueous polyurethane adhesive samples prepared in Examples 3-8 and Comparative Examples 1 and 2 were placed in an oven, and the temperature and placement time were set to 60 °C × 7 days. After the expiration date, the samples were taken out of the oven and left to stand at room temperature for 1 h, and then observed whether the adhesive samples showed delamination.

[0045] Table 1

[0046] From the results in Table 1, it can be seen that the antistatic inorganic nano-hybrid aqueous polyurethanes in Examples 3-8 improve the bonding performance of the aqueous polyurethane adhesive at room temperature and at a high temperature of 80 °C by adding nano-silica or amino-coupling agent-modified nano-silica. This is because a large number of Si-OH are contained on the surface of nano-silica, and its own polar groups can increase the bonding strength between the adhesive and the adherend, and also react with -COO in polyurethane. -Or the urethane bond -NHCOO- forms hydrogen bonds, thereby improving the adhesive strength and cohesive strength of the adhesive. At the same time, this hydrogen bond network can increase the stability of the inorganic stannous oxide sol, making it not easy to settle in the waterborne polyurethane system. Thus, the stannous oxide sol is evenly dispersed, which can provide a lower surface resistance, make the surface charge distribution of the PU rubber sheet more uniform, and reduce the local charge density to obtain a higher antistatic effect.

[0047] In Comparative Example 1, nano-silica or amino-coupling agent modified nano-silica and stannous oxide sol were not used, and the adhesive strength at 80 °C was significantly reduced. Moreover, after brushing on the surface of the PU rubber sheet, the measured surface resistance was significantly higher, resulting in slow dissipation of surface charges and poor antistatic performance.

[0048] In Comparative Example 2, nano-silica or amino-coupling agent modified nano-silica was not used, and only stannous oxide hydrosol was added. The adhesive strength at 80 °C was significantly reduced, and the stability of the stannous oxide sol in the waterborne polyurethane system was poor. Through the accelerated stability test, it was found that stannous oxide was easy to precipitate out of the polyurethane system, resulting in a significantly higher measured surface resistance after brushing on the surface of the PU rubber sheet and poor antistatic effect.

[0049] In Comparative Example 3, the amino-coupling agent modified nano-silica of Example 1 was used, but stannous oxide hydrosol was not used. The adhesive strength at 80 °C was improved, but the lack of an inorganic antistatic agent led to a significantly higher measured surface resistance after brushing on the surface of the PU rubber sheet and poor antistatic effect.

[0050] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of them. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention. Although the specific implementation manners of the present invention have been described above, it does not limit the protection scope of the present invention. Those skilled in the art should understand that based on the technical solutions of the present invention, various modifications or deformations that can be made without creative efforts by those skilled in the art are still within the protection scope of the present invention.

Claims

1. An antistatic inorganic nano-hybrid waterborne polyurethane composition, characterized in that: include: Any one of polyurethane prepolymer, nano-tin oxide, nano-silicon dioxide or nano-silicon dioxide modified by an amino coupling agent; Wherein, the nano-tin oxide is selected from tin oxide particles or tin oxide aqueous dispersion, and the average particle size of the tin oxide is not more than 100 nm; Nano-silicon dioxide is selected from silicon dioxide particles or silicon dioxide aqueous dispersion, and the average particle size of the silicon dioxide does not exceed 100nm; The polyurethane prepolymer comprises a hydrophilic chain extender and at least two polyols with different glass transition temperatures. The polyurethane prepolymer is terminated with -NCO groups. The hydrophilic chain extender is a polyol or polyamine containing at least one -COOH or -SO3H group.

2. The antistatic inorganic nano-hybrid waterborne polyurethane composition according to claim 1, characterized in that: The nano silicon dioxide modified by an amino coupling agent comprises the following raw materials in parts by weight: 15 to 30 parts of an amino silane coupling agent, 5 to 15 parts of methyl orthosilicate or ethyl orthosilicate, 1 to 20 parts of water, 50 to 70 parts of an alcohol solvent, and 0.001 to 0.01 parts of a catalyst; Wherein, the amino-containing silane coupling agent is selected from: any one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, N-aminoethyl-3-aminopropyltrimethoxysilane or N-aminoethyl-3-aminopropylmethyldimethoxysilane.

3. The antistatic inorganic nano-hybrid waterborne polyurethane composition according to claim 2, characterized in that: The alcohol solvent is selected from any one or more of methanol, ethanol or isopropanol; And / or, the catalyst is selected from any one or more of tetrabutyl titanate or dibutyltin dilaurate; And / or, using a sol-gel method to synthesize nano-silica modified with an amino coupling agent.

4. The antistatic inorganic nano-hybrid waterborne polyurethane composition according to claim 1, characterized in that: The polyurethane prepolymer comprises the following raw materials in parts by weight: 68-72 parts of polyol, 23-24 parts of diisocyanate, 4-7 parts of hydrophilic chain extender, 2-4 parts of polyol chain extender, 1-2 parts of neutralizer, and 0.001-0.01 parts of catalyst; Wherein, the number average molecular weight of the polyol is in the range of 200 to 4000.

5. The antistatic inorganic nano-hybrid waterborne polyurethane composition according to claim 4, characterized in that: The polyol is selected from: one or both of polyester polyol and polyether polyol; And / or, the diisocyanate is selected from: one or more of isophorone diisocyanate, diphenylmethane diisocyanate, toluene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and 1,6-hexamethylene diisocyanate; And / or, the hydrophilic chain extender is selected from at least one of dimethylolbutyric acid, dimethylolpropionic acid, and sodium ethylenediaminesulfonate; And / or, the polyol chain extender is selected from: one or more of 1,4-butanediol, 1,6-hexanediol, and 1,3-butanediol; And / or, the neutralizing agent is selected from: one or more of triethylamine, triethanolamine, and N,N-dimethylethanolamine; And / or, the catalyst is selected from any one or more of an organic bismuth catalyst and an organic tin catalyst.

6. The antistatic inorganic nano-hybrid waterborne polyurethane composition according to claim 1, characterized in that: The preparation method of the polyurethane prepolymer comprises: S1, mixing a polyol, a diisocyanate and a hydrophilic chain extender together for reaction, then adding a polyol chain extender for reaction, and then adding a catalyst for reaction until the -NCO content of the reaction mixture is ≤10wt%; S2, neutralization reaction: cool the polyurethane prepolymer to 30-60°C, add a neutralizing agent under the shearing action of a high-speed disperser, and react for 5-60 minutes.

7. The antistatic inorganic nano-hybrid waterborne polyurethane composition according to claim 6, characterized in that: In step S1, acetone in an amount of 1 to 2 times the total weight of the hydrophilic chain extender is added during the mixing of the polyol, the diisocyanate and the hydrophilic chain extender; and / or, after cooling in step S2, first adding 40-60 wt % of acetone to the polyurethane prepolymer to reduce the viscosity of the polyurethane prepolymer, and then adding a neutralizing agent to carry out a neutralization reaction under the shearing action of a high-speed disperser; And / or, the method for preparing the polyurethane prepolymer further includes: S3, a deketone process, wherein the temperature is set at 40-60° C., the pressure in the container does not exceed 0.1 Pa, and the acetone is removed by vacuum.

8. A method for preparing an antistatic inorganic nano-hybrid waterborne polyurethane composition, characterized in that: The polyurethane prepolymer, nano-stannous oxide, nano-silicon dioxide or nano-silicon dioxide modified by an amino coupling agent are mixed and uniformly dispersed by a mechanical method to obtain the antistatic inorganic nano-hybrid waterborne polyurethane composition as claimed in any one of claims 1 to 7.

9. A use for bonding a polyurethane substrate to a plastic substrate, characterized in that: Use of the antistatic inorganic nano-hybrid waterborne polyurethane composition as claimed in any one of claims 1 to 7 for bonding between a polyurethane substrate and a plastic substrate; Wherein, the plastic substrate includes any one of polybutylene terephthalate, polycarbonate, polyamide, acrylonitrile-butadiene-styrene copolymer and polyphenylene sulfide.

10. A use of an automobile interior coating adhesive, characterized in that: Use of the antistatic inorganic nano-hybrid waterborne polyurethane composition as claimed in any one of claims 1 to 7 as an automotive interior coating adhesive.

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