Antistatic polyurethane resin, its preparation method and application

Abstract

The application provides an antistatic polyurethane resin and a preparation method and application thereof, and the antistatic polyurethane resin comprises a polyurethane resin, betel leaf carbon nanospheres and a solvent; and the preparation raw material of the polyurethane resin comprises a polyol, a chain extender, isocyanate and a catalyst. The antistatic polyurethane resin provided in the application has excellent antistatic property and heat resistance, is suitable for preparing antistatic polyurethane synthetic leather, and the preparation process of the antistatic polyurethane resin is simple, and the cost and energy consumption are low.

Description

Technical Field

[0001] This invention belongs to the field of polyurethane technology, specifically relating to an antistatic polyurethane resin, its preparation method, and its application. Background Technology

[0002] In recent years, antistatic materials have gradually become popular in the market, such as antistatic work clothes, antistatic four-piece sets, antistatic wristbands and antistatic watches. As a result, people have also conducted a lot of research on antistatic polyurethane.

[0003] CN115975523A discloses an antistatic polyurethane protective film and its preparation method. The antistatic polyurethane protective film is formed by sequentially laminating a substrate film, a pressure-sensitive adhesive, and a release film. The substrate film is an intercalated PET film; the pressure-sensitive adhesive is a polyurethane pressure-sensitive adhesive; and the ion-exchange film is a PET release film. The intercalated PET film is composed of the following components by weight: 76-82 parts PET resin, 1-3 parts intercalating agent, 12-15 parts nano-silica, 4-6 parts epoxidized soybean oil, and 0.5-0.8 parts additives. This technical solution, by introducing an intercalating agent into the intercalated PET film, can greatly improve the antistatic performance of the intercalated PET film. Simultaneously, by introducing the intercalating agent, the antistatic performance of the antistatic polyurethane protective film can be greatly extended. However, the preparation process of the intercalating agent is relatively complex.

[0004] CN116144255A discloses an antistatic waterborne polyurethane mortar flooring material and its preparation method. The antistatic waterborne polyurethane mortar flooring material includes a first component, a second component, and a third component. The first component includes: 60-70 parts of waterborne polyurethane plant resin, 10-25 parts of pure water, 10-25 parts of conductive mica powder, and 5-15 parts of color paste. The waterborne polyurethane plant resin is a hydroxyl-based waterborne polyol. The conductive mica powder is mica powder with a surface coated with titanium dioxide, tin dioxide, and antimony tetroxide. The second component includes: 15-30 parts of waterborne isocyanate and 1-6 parts of additives. The waterborne isocyanate is a hydrophilically modified aliphatic isocyanate curing agent. The additives are one of waterborne defoamers, leveling agents, and rheology modifiers. The third component includes: 5-15 parts of calcium hydroxide, 2-8 parts of quartz sand, 5-10 parts of 52.5 grade white cement, and 0.2-1 parts of carbon fiber. The antistatic water-based polyurethane mortar flooring material prepared by this technical solution dissipates static charge quickly, has excellent physical and chemical properties after film formation, and has a long service life.

[0005] However, in existing technologies, antistatic materials are prone to agglomeration when combined with polyurethane, and the performance of antistatic polyurethane still needs to be improved. At the same time, the preparation of antistatic polyurethane synthetic leather has not been given enough attention.

[0006] Therefore, there is a need to develop an antistatic polyurethane resin with good antistatic properties that is suitable for preparing antistatic polyurethane synthetic leather. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide an antistatic polyurethane resin, its preparation method, and its applications. The antistatic polyurethane resin possesses excellent antistatic properties and thermodynamic performance.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides an antistatic polyurethane resin, the antistatic polyurethane resin comprising a polyurethane resin, areca leaf carbon nanospheres and a solvent.

[0010] The raw materials for preparing the polyurethane resin include polyols, chain extenders, isocyanates, and catalysts.

[0011] In this invention, the areca leaf carbon nanospheres are carbon materials obtained from nature, which are safe, environmentally friendly, and renewable. Areca leaves are typically treated as waste; preparing them into carbon nanospheres represents waste recycling and is inexpensive. The carbon nanospheres possess good electrical conductivity and excellent heat resistance. An antistatic polyurethane resin is prepared by composite composition of polyurethane resin, areca leaf carbon nanospheres, and solvent. This resin exhibits excellent antistatic and thermodynamic properties, good heat resistance, and is suitable for preparing antistatic polyurethane synthetic leather.

[0012] Preferably, the solvent includes acetone.

[0013] Preferably, the polyol includes any one or a combination of at least two of the following: polytetramethyl ether glycol, polybutylene adipate glycol, polypropylene oxide ether glycol, or polymethyl propylene adipate glycol.

[0014] Preferably, the weight-average molecular weight of the polyol is 1000-4000, such as 1300, 1600, 1900, 2100, 2400, 2700, 3000, 3300, 3600 or 3900.

[0015] In this invention, the weight-average molecular weight of the polyol is preferably 1000-4000. If the weight-average molecular weight is too large, the reaction rate will be very slow when preparing polyurethane resin. If the weight-average molecular weight is too small, it will be detrimental to the foaming of polyurethane resin.

[0016] Preferably, the chain extender comprises any one or a combination of at least two of 1,4-butanediol, ethylene glycol, diethylene glycol, or monoethanolamine.

[0017] Preferably, the isocyanate includes any one or a combination of at least two of diphenylmethane diisocyanate (MDI), hydrogenated diphenylmethane diisocyanate (HMDI), or toluene diisocyanate (TDI).

[0018] Preferably, the catalyst comprises any one or a combination of at least two of organobismuth, stannous octoate, or dibutyltin dilaurate.

[0019] Preferably, the raw materials for preparing the polyurethane resin include the following components by weight: 60-70 parts of polyol (e.g., 61, 62, 63, 64, 65, 66, 67, 68, or 69 parts, etc.), 2-8 parts of chain extender (e.g., 3, 4, 5, 6, or 7 parts, etc.), 20-40 parts of isocyanate (e.g., 22, 24, 26, 28, 30, 32, 34, 36, or 38 parts, etc.), and 0.01-0.05 parts of catalyst (e.g., 0.015, 0.020, 0.025, 0.030, 0.035, 0.040, or 0.045 parts, etc.).

[0020] Preferably, the mass of the areca leaf carbon nanospheres is 0.2% to 1% of the mass of the polyurethane resin, such as 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, or 0.9%.

[0021] Preferably, the raw materials for preparing the polyurethane resin also include an organic solvent.

[0022] Preferably, the organic solvent includes any one or a combination of at least two of acetone, butanone, N,N-dimethylacetamide, or N,N-dimethylformamide.

[0023] Preferably, the organic solvent is 30% to 70% of the total mass of the polyol, chain extender, isocyanate and catalyst, for example, 35%, 40%, 45%, 50%, 55%, 60% or 65%.

[0024] In a second aspect, the present invention provides a method for preparing the antistatic polyurethane resin as described in the first aspect, the method comprising the following steps:

[0025] (1) Carbonize areca leaves and treat them with acid to obtain areca leaf carbon nanospheres;

[0026] (2) Mix polyol, chain extender, isocyanate and catalyst, and react to obtain polyurethane resin;

[0027] (3) The areca leaf carbon nanospheres obtained in step (1) are added to a solvent and ultrasonically dispersed, and then mixed with the polyurethane resin obtained in step (2) to obtain the antistatic polyurethane resin.

[0028] Steps (1) and (2) can be performed in any order, or simultaneously.

[0029] Preferably, the acid in step (1) includes a nitric acid solution.

[0030] Preferably, the concentration of the nitric acid solution is 3 to 6 mol / L, such as 3.3 mol / L, 3.6 mol / L, 3.9 mol / L, 4.2 mol / L, 4.5 mol / L, 4.8 mol / L, 5.1 mol / L, 5.4 mol / L, or 5.7 mol / L.

[0031] Preferably, step (1) specifically includes the following steps:

[0032] (I) Dry the areca leaves, carbonize them, and grind them to obtain a black fine powder.

[0033] (II) The black fine powder obtained in (I) is mixed with acid, heated and stirred under reflux, diluted, centrifuged and dried to obtain the areca leaf carbon nanospheres.

[0034] Preferably, the drying temperature in step (I) is 40-80℃ (e.g., 45℃, 50℃, 55℃, 60℃, 65℃, 70℃ or 75℃, etc.), and the time is 2-6h (e.g., 2.5h, 3h, 3.5h, 4h, 4.5h, 5h or 5.5h, etc.).

[0035] Preferably, the carbonization in step (I) is carried out in a tubular furnace or a muffle furnace.

[0036] Preferably, the carbonization temperature in step (I) is 300–500°C (e.g., 320°C, 340°C, 360°C, 380°C, 400°C, 420°C, 440°C, 460°C, or 480°C, etc.), and the carbonization time is 10–18 hours (e.g., 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, or 17 hours, etc.).

[0037] Preferably, the grinding time in step (I) is 3 to 5 hours, such as 3.2 hours, 3.4 hours, 3.6 hours, 3.8 hours, 4.0 hours, 4.2 hours, 4.4 hours, 4.6 hours or 4.8 hours.

[0038] Preferably, the temperature of the heating, stirring and reflux in step (II) is 80-120°C (e.g., 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C or 120°C, etc.), and the time is 10-16h (e.g., 11h, 12h, 13h, 14h or 15h, etc.).

[0039] Preferably, the centrifugation speed in step (II) is 3000–5000 r / min (e.g., 3200 r / min, 3400 r / min, 3600 r / min, 3800 r / min, 4000 r / min, 4200 r / min, 4400 r / min, 4600 r / min or 4800 r / min, etc.), and the centrifugation time is 15–30 min (e.g., 17 min, 19 min, 21 min, 23 min, 25 min, 27 min or 29 min, etc.).

[0040] Preferably, the drying temperature in step (II) is 60-90℃ (e.g., 63℃, 66℃, 69℃, 72℃, 75℃, 78℃, 91℃, 94℃ or 97℃, etc.), and the drying time is 6-10h (e.g., 6.5h, 7h, 7.5h, 8h, 8.5h, 9h or 9.5h, etc.).

[0041] Preferably, step (2) specifically includes the following steps: mixing polyol, chain extender and organic solvent, adding isocyanate, performing a first reaction, adding catalyst, performing a second reaction, and obtaining polyurethane resin.

[0042] Preferably, the first and second reactions are carried out under the protection of an inert gas.

[0043] Preferably, the temperatures of the first and second reactions are each independently 65–85°C (e.g., 67°C, 69°C, 71°C, 73°C, 75°C, 77°C, 79°C, 81°C, or 83°C, etc.).

[0044] Preferably, the time for the first reaction is 6 to 10 hours (e.g., 6.5 hours, 7 hours, 7.5 hours, 8 hours, 8.5 hours, 9 hours, or 9.5 hours).

[0045] Preferably, the second reaction takes 4 to 8 hours, such as 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, or 7.5 hours.

[0046] Preferably, the power of the ultrasound in step (3) is 500-1000W (e.g., 550W, 600W, 650W, 700W, 750W, 800W, 850W, 900W or 950W, etc.), and the ultrasound time is 15-40min (e.g., 18min, 21min, 24min, 27min, 30min, 33min, 36min or 39min, etc.).

[0047] Preferably, the mass ratio of areca leaf carbon nanospheres to solvent in step (3) is 1:3 to 1:6, for example, 1:3.5, 1:4, 1:4.5, 1:5 or 1:5.5.

[0048] Preferably, the mixing in step (3) includes stirring and mixing for a time of 1 to 3 hours, such as 1.2 hours, 1.4 hours, 1.6 hours, 1.8 hours, 2.0 hours, 2.2 hours, 2.4 hours, 2.6 hours or 2.8 hours.

[0049] Thirdly, the present invention provides an antistatic polyurethane synthetic leather, the antistatic polyurethane synthetic leather comprising a polyurethane resin layer, an adhesive layer and a base fabric stacked sequentially, wherein the raw materials for preparing the polyurethane resin layer include the antistatic polyurethane resin as described in the first aspect.

[0050] Fourthly, the present invention provides a method for preparing antistatic polyurethane synthetic leather as described in the third aspect, the method comprising the following steps:

[0051] (a) Coating the surface of release paper with the antistatic polyurethane resin as described in the first aspect, and drying it to obtain a polyurethane resin layer;

[0052] (b) The surface of the polyurethane resin layer obtained in step (a) is coated with an adhesive, the base fabric is bonded, dried, and the release paper is removed to obtain the antistatic polyurethane synthetic leather.

[0053] Preferably, the coating thickness in step (a) is 0.5 to 2 mm, such as 0.7 mm, 0.9 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm or 1.9 mm.

[0054] Preferably, the drying temperature in step (a) is 80-100℃ (e.g., 82℃, 84℃, 86℃, 88℃, 90℃, 92℃, 94℃, 96℃ or 98℃, etc.), and the time is 10-30min, e.g., 12min, 14min, 16min, 18min, 20min, 22min, 24min, 26min or 28min, etc.

[0055] Preferably, the coating thickness in step (b) is 0.5 to 2 mm, for example, 0.7 mm, 0.9 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm or 1.9 mm.

[0056] Preferably, the drying temperature in step (b) is 100–140°C (e.g., 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, or 135°C, etc.), and the drying time is 20–40 min (e.g., 22 min, 24 min, 26 min, 28 min, 30 min, 32 min, 34 min, 36 min, or 38 min, etc.).

[0057] Preferably, the base fabric comprises microfiber base.

[0058] Preferably, the adhesive includes any one or a combination of at least two of adhesives XCA-4505, XCA-4515SE, XCA-4516H, or XCA-4525A.

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] In this invention, the areca leaf carbon nanospheres are carbon materials obtained from nature, which are safe, environmentally friendly, and renewable. The antistatic polyurethane resin prepared by composite composition of polyurethane resin, areca leaf carbon nanospheres, and solvent exhibits better thermodynamic properties, excellent antistatic properties, and heat resistance, making it suitable for preparing antistatic polyurethane synthetic leather. The preparation process of the antistatic polyurethane resin of this invention is simple, with low cost and energy consumption, and the resulting product has excellent performance and promising application prospects. The softening point of the antistatic polyurethane resin is 182-226℃, and the surface insulation resistance of the antistatic polyurethane synthetic leather is 1.1×10⁻⁶. 3 ~2.2×10 7 Ω; Preferably, the softening point of the antistatic polyurethane resin is 201-205℃, it has good heat resistance, and the surface insulation resistance of the antistatic polyurethane synthetic leather is 1.1×10⁻⁶. 3 -2.3×10 4 Ω. Detailed Implementation

[0061] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0062] Example 1

[0063] This embodiment provides an antistatic polyurethane resin, its preparation method, and an antistatic polyurethane synthetic leather. The antistatic polyurethane resin includes polyurethane resin, areca leaf carbon nanospheres, and a solvent (acetone); the mass of the areca leaf carbon nanospheres is 1% of the mass of the polyurethane resin.

[0064] The raw materials for preparing the polyurethane resin include the following components by weight: 70 parts of polyol (polytetramethyl ether glycol, weight average molecular weight of 1000), 2 parts of chain extender (1,4-butanediol), 23 parts of isocyanate (diphenylmethane diisocyanate), 0.05 parts of catalyst (bismuth quinocetate, Shandong Rongxin Chemical), and 66.5 parts of organic solvent (acetone). The organic solvent accounts for 70% of the total mass of the polyol, chain extender, isocyanate, and catalyst.

[0065] The preparation method of the antistatic polyurethane resin is as follows:

[0066] (1) Dry the areca leaves in an oven at 40°C for 6 hours, then put them in a crucible and heat them in a tube furnace at 300°C for 18 hours. Grind them for 4 hours to obtain a black fine powder.

[0067] Take 1g of the above black fine powder and mix it with 60mL of 3mol / L nitric acid solution in a 100mL single-necked flask equipped with a condenser. Heat and stir under reflux at 80℃ for 16h. After cooling, dilute with distilled water and centrifuge at 3000r / min for 30min. Finally, dry in a 60℃ oven for 10h to obtain the areca leaf carbon nanospheres.

[0068] (2) Mix the polyol, chain extender and organic solvent, add isocyanate, purge with nitrogen, heat to 65°C, react for 6 hours, add catalyst, and continue to react for 4 hours until the isocyanate is completely reacted to obtain the polyurethane resin.

[0069] (3) Add 1.6 parts by weight of the areca leaf carbon nanospheres obtained in step (1) to 9.7 parts by weight of solvent (acetone), disperse them under an ultrasonic generator with a power of 1000W for 40 minutes, and then mix them with the polyurethane resin obtained in step (2) to obtain the antistatic polyurethane resin.

[0070] The preparation method of the antistatic polyurethane synthetic leather is as follows:

[0071] (a) Coating the surface of the release paper with the above-mentioned antistatic polyurethane resin with a coating thickness of 2 mm, and then drying it in an 80°C oven for 30 min to obtain a polyurethane resin layer.

[0072] (b) The surface of the polyurethane resin layer obtained in step (a) is coated with an adhesive (XCA-4505 adhesive from Asahikawa Chemicals) with a coating thickness of 0.5 mm, and the base fabric (microfiber base) is attached. The layer is then placed in an oven at 140°C and dried for 20 min. The release paper is removed to obtain the antistatic polyurethane synthetic leather.

[0073] Example 2

[0074] This embodiment provides an antistatic polyurethane resin and its preparation method, as well as an antistatic polyurethane synthetic leather. The antistatic polyurethane resin includes polyurethane resin, areca leaf carbon nanospheres, and solvent (acetone); the mass of the areca leaf carbon nanospheres is 0.5% of the mass of the polyurethane resin.

[0075] The raw materials for preparing the polyurethane resin include the following components by weight: 65 parts of polyol (polypropylene ether glycol, weight average molecular weight of 2000), 5 parts of chain extender (ethylene glycol), 29.7 parts of isocyanate (hydrogenated diphenylmethane diisocyanate), 0.03 parts of catalyst (stannous octoate), and 49.8 parts of organic solvent (butanone). The organic solvent accounts for 50% of the total mass of the polyol, chain extender, isocyanate, and catalyst.

[0076] The preparation method of the antistatic polyurethane resin is as follows:

[0077] (1) Dry the areca leaves in an oven at 60°C for 4 hours, then put them in a crucible and heat them in a tube furnace at 400°C for 14 hours. Grind them for 3 hours to obtain a black fine powder.

[0078] Take 3g of the above-mentioned black fine powder and mix it with 60mL of 5mol / L nitric acid solution in a 100mL single-necked flask equipped with a condenser. Heat and stir under reflux at 90℃ for 13h. After cooling, dilute with distilled water and centrifuge at 4000r / min for 20min. Finally, dry in a 70℃ oven for 8h to obtain the areca leaf carbon nanospheres.

[0079] (2) Mix the polyol, chain extender and organic solvent, add isocyanate, purge with nitrogen, heat to 70°C, react for 8 hours, add catalyst, and continue to react for 5 hours until the isocyanate is completely reacted to obtain the polyurethane resin.

[0080] (3) Add 0.75 parts by weight of the areca leaf carbon nanospheres obtained in step (1) to 3.4 parts by weight of solvent (acetone), disperse them under an 800W ultrasonic generator for 30 minutes, and then mix them with the polyurethane resin obtained in step (2) to obtain the antistatic polyurethane resin.

[0081] The preparation method of the antistatic polyurethane synthetic leather is as follows:

[0082] (a) Coating the surface of the release paper with the above-mentioned antistatic polyurethane resin with a coating thickness of 1.5 mm, and then drying it in a 90°C oven for 20 min to obtain a polyurethane resin layer.

[0083] (b) The surface of the polyurethane resin layer obtained in step (a) is coated with an adhesive (Asahikawa Chemical Adhesive XCA-4515SE) with a coating thickness of 1 mm, and then bonded with a base fabric (microfiber base). The layer is then placed in an oven at 120°C and dried for 30 min. The release paper is removed to obtain the antistatic polyurethane synthetic leather.

[0084] Example 3

[0085] This embodiment provides an antistatic polyurethane resin and its preparation method, as well as an antistatic polyurethane synthetic leather. The antistatic polyurethane resin includes polyurethane resin, areca leaf carbon nanospheres, and solvent (acetone); the mass of the areca leaf carbon nanospheres is 0.2% of the mass of the polyurethane resin.

[0086] The raw materials for preparing the polyurethane resin include the following components by weight: 60 parts of polyol (polypropylene ether glycol, weight average molecular weight of 4000), 8 parts of chain extender (monoethanolamine), 38 parts of isocyanate (hydrogenated diphenylmethane diisocyanate), 0.01 parts of catalyst (dibutyltin dilaurate), and 31.8 parts of organic solvent (N,N-dimethylformamide). The organic solvent accounts for 30% of the total mass of the polyol, chain extender, isocyanate, and catalyst.

[0087] The preparation method of the antistatic polyurethane resin is as follows:

[0088] (1) Dry the areca leaves in an oven at 80°C for 2 hours, then put them in a crucible and heat them in a tube furnace at 500°C for 10 hours. Grind them for 5 hours to obtain a black fine powder.

[0089] Take 5g of the above-mentioned black fine powder and mix it with 60mL of 6mol / L nitric acid solution in a 100mL single-necked flask equipped with a condenser. Heat and stir under reflux at 100℃ for 10h. After cooling, dilute with distilled water and centrifuge at 5000r / min for 15min. Finally, dry in a 90℃ oven for 6h to obtain the areca leaf carbon nanospheres.

[0090] (2) Mix the polyol, chain extender and organic solvent, add isocyanate, purge with nitrogen, heat to 85°C, react for 10 h, add catalyst, and continue to react for 6 h until the isocyanate is completely reacted to obtain the polyurethane resin.

[0091] (3) Add 0.27 parts by weight of the areca leaf carbon nanospheres obtained in step (1) to 0.85 parts by weight of solvent (acetone), disperse them under an ultrasonic generator with a power of 500W for 40 minutes, and then mix them with the polyurethane resin obtained in step (2) to obtain the antistatic polyurethane resin.

[0092] The preparation method of the antistatic polyurethane synthetic leather is as follows:

[0093] (a) The above-mentioned antistatic polyurethane resin is coated on the surface of the release paper with a coating thickness of 0.5 mm, and then placed in an oven at 100°C for 10 min to dry, thereby obtaining a polyurethane resin layer.

[0094] (b) The surface of the polyurethane resin layer obtained in step (a) is coated with an adhesive (XACHA-4516H adhesive from Asahikawa Chemicals) with a coating thickness of 2 mm. The base fabric (microfiber base) is then bonded to the surface and dried in an oven at 100°C for 20 min. The release paper is then removed to obtain the antistatic polyurethane synthetic leather.

[0095] Example 4

[0096] This embodiment provides an antistatic polyurethane resin and its preparation method, as well as an antistatic polyurethane synthetic leather. The only difference between this embodiment and Embodiment 1 is that the weight of areca leaf carbon nanospheres in step (3) is adjusted to 0.2 parts, and the mass of the areca leaf carbon nanospheres is 0.1% of the mass of the polyurethane resin. The rest is the same as in Embodiment 1.

[0097] Example 5

[0098] This embodiment provides an antistatic polyurethane resin and its preparation method, as well as an antistatic polyurethane synthetic leather. The only difference between this embodiment and Embodiment 1 is that the weight of areca leaf carbon nanospheres in step (3) is adjusted to 2 parts, and the mass of the areca leaf carbon nanospheres is 1.2% of the mass of the polyurethane resin. The rest is the same as in Embodiment 1.

[0099] Example 6

[0100] This embodiment provides an antistatic polyurethane resin and its preparation method, as well as an antistatic polyurethane synthetic leather. The only difference between this embodiment and Example 1 is that the concentration of the nitric acid solution is adjusted to 1 mol / L, while the rest is the same as Example 1.

[0101] Example 7

[0102] This embodiment provides an antistatic polyurethane resin and its preparation method, as well as an antistatic polyurethane synthetic leather. The only difference between this embodiment and Embodiment 1 is that the heating, stirring and reflux temperature in step (1) is adjusted to 60°C and the reflux time is adjusted to 6h. The rest is the same as in Embodiment 1.

[0103] Comparative Example 1

[0104] This comparative example provides an antistatic polyurethane resin and its preparation method, as well as an antistatic polyurethane synthetic leather. The only difference between this example and Example 1 is that step (3) does not include the step of adding 9.7 parts by weight of solvent (acetone) and dispersing it for 40 minutes under a 1000W ultrasonic generator. The rest is the same as Example 1.

[0105] Comparative Example 2

[0106] This comparative example provides a polyurethane resin and its preparation method, as well as a polyurethane synthetic leather. The only difference between this example and Example 1 is that areca leaf carbon nanospheres are not added. The preparation method of the polyurethane synthetic leather is adjusted as follows:

[0107] (a) Coat the surface of the release paper with the polyurethane resin obtained in step (2) with a coating thickness of 2 mm, and then dry it in an 80°C oven for 30 min to obtain a polyurethane resin layer.

[0108] (b) The surface of the polyurethane resin layer obtained in step (a) is coated with an adhesive (XCA-4505 adhesive from Asahikawa Chemicals) with a coating thickness of 0.5 mm, and then bonded with a base fabric (microfiber base). The layer is then placed in an oven at 140°C and dried for 20 min. The release paper is then removed to obtain the polyurethane synthetic leather.

[0109] Comparative Example 3

[0110] This comparative example provides an antistatic polyurethane resin and its preparation method, as well as an antistatic polyurethane synthetic leather. The only difference between this example and Example 1 is that the areca leaves are replaced with wheat straw of the same mass; otherwise, they are the same as in Example 1.

[0111] Everything else is the same as in Example 1.

[0112] The antistatic polyurethane resin, antistatic polyurethane synthetic leather, polyurethane resin, and polyurethane synthetic leather provided in the above embodiments and comparative examples were subjected to the following performance tests.

[0113] (1) Surface insulation resistance: The surface insulation resistance of antistatic polyurethane synthetic leather and polyurethane synthetic leather shall be tested in accordance with GB / T 24249-2009.

[0114] (2) Softening point: The softening point of antistatic polyurethane resin and polyurethane resin shall be tested in accordance with GB / T 12007.6-1989.3.

[0115] The test results are shown in Table 1 below:

[0116] Table 1

[0117] Softening point (°C) Surface insulation resistance (Ω) Example 1 205 <![CDATA[1.1×10 3 ]]> Example 2 201 <![CDATA[1.6×10 3 ]]> Example 3 205 <![CDATA[2.3×10 4 ]]> Example 4 195 <![CDATA[3.3×10 6 ]]> Example 5 226 <![CDATA[1.1×10 3 ]]> Example 6 182 <![CDATA[2.2×10 7 ]]> Example 7 189 <![CDATA[1.5×10 7 <!-- 7 -->]]> Comparative Example 1 178 <![CDATA[2.3×10 10 ]]> Comparative Example 2 171 <![CDATA[3.2×10 15 ]]> Comparative Example 3 169 <![CDATA[4.5×10 10 ]]>

[0118] As shown in Table 1, the softening point of the antistatic polyurethane resin provided in Examples 1-7 is 182-226℃, and the surface insulation resistance of the antistatic polyurethane synthetic leather is 1.1×10⁻⁶. 3 ~2.2×10 7 Ω; The antistatic polyurethane resins provided in Examples 1-3 have a softening point of 201-205℃, good heat resistance, and the surface insulation resistance of the antistatic polyurethane synthetic leather is 1.1×10⁻⁶. 3 -2.3×104 Ω.

[0119] Compared to Example 1, if the percentage of areca leaf carbon nanospheres to polyurethane resin is too low (Example 4), the prepared antistatic polyurethane synthetic leather has a lower softening point, a higher surface insulation resistance, and poorer antistatic performance. If the percentage of areca leaf carbon nanospheres to polyurethane resin is too high (Example 5), the softening point is higher, and the antistatic performance is better. However, the excessive carbon nanosphere content results in a lower polyurethane resin content, leading to a stiff feel and easy precipitation causing fogging in the prepared antistatic polyurethane synthetic leather. Therefore, it can be concluded that within a specific range of the percentage of areca leaf carbon nanospheres to polyurethane resin, the prepared antistatic polyurethane resin and antistatic polyurethane synthetic leather exhibit better performance.

[0120] Compared to Example 1, if the concentration of the nitric acid solution is too low (Example 6), the softening point of the antistatic polyurethane resin decreases, and the surface insulation resistance of the antistatic polyurethane synthetic leather decreases. This is because a low nitric acid concentration prevents impurities in the black fine powder from being effectively removed, leaving a significant amount of residue. Therefore, it can be concluded that within a specific range of nitric acid solution concentration, the prepared antistatic polyurethane resin and antistatic polyurethane synthetic leather exhibit better performance.

[0121] Compared with Example 1, if the reflow temperature is lower (Example 7), impurities in the black fine powder cannot be effectively removed, leaving more impurities, lowering the softening point, and increasing the surface insulation resistance.

[0122] Compared with Example 1, if the ultrasonic dispersion step (3) of the preparation method of antistatic polyurethane resin is not included (Comparative Example 1), the softening point of antistatic polyurethane resin is reduced and the surface insulation resistance of antistatic polyurethane synthetic leather is reduced. The reason is that ultrasound is beneficial to the uniform dispersion of areca leaf carbon nanospheres. Without the ultrasonic dispersion step, the uneven dispersion of areca leaf carbon nanospheres is likely to cause them to agglomerate in the final antistatic polyurethane synthetic leather, affecting the antistatic performance of the final product.

[0123] Compared with Example 1, if areca leaf carbon nanospheres are not added (Comparative Example 2), the softening point of the polyurethane resin is lower, and the surface insulation resistance of the resulting polyurethane synthetic leather is reduced.

[0124] Compared with Example 1, if the areca leaves are replaced with wheat straw, the antistatic performance decreases. This is because the carbon nanomaterials prepared from wheat straw have lower performance than the areca leaf carbon nanospheres prepared from areca leaves.

[0125] The applicant declares that the present invention is illustrated by the above embodiments to demonstrate an antistatic polyurethane resin, its preparation method, and its application. However, the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials of the product, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. An antistatic polyurethane synthetic leather, characterized in that, The antistatic polyurethane synthetic leather comprises a polyurethane resin layer, an adhesive layer, and a base fabric stacked sequentially, wherein the raw material for preparing the polyurethane resin layer includes antistatic polyurethane resin. The antistatic polyurethane resin includes polyurethane resin, areca leaf carbon nanospheres, and solvent. The raw materials for preparing the polyurethane resin include polyols, chain extenders, isocyanates, and catalysts. The antistatic polyurethane resin is prepared by the following method, which includes the following steps: (1) Carbonize areca leaves and treat them with acid to obtain the areca leaf carbon nanospheres; (2) Mix polyol, chain extender, isocyanate and catalyst, and react to obtain polyurethane resin; (3) The areca leaf carbon nanospheres obtained in step (1) are added to a solvent and ultrasonically dispersed, and then mixed with the polyurethane resin obtained in step (2) to obtain the antistatic polyurethane resin. Steps (1) and (2) can be performed in any order, or simultaneously. The mass of the areca leaf carbon nanospheres is 0.2% to 1% of the mass of the polyurethane resin.

2. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The solvent includes acetone.

3. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The polyols include any one or a combination of at least two of the following: polytetramethylene ether glycol, polybutylene adipate glycol, polypropylene oxide ether glycol, or polymethyl propylene adipate glycol.

4. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The weight-average molecular weight of the polyol is 1000-4000.

5. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The chain extender includes any one or a combination of at least two of 1,4-butanediol, ethylene glycol, diethylene glycol, or monoethanolamine.

6. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The isocyanate includes any one or a combination of at least two of diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, or toluene diisocyanate.

7. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The catalyst comprises any one or a combination of at least two of organobismuth, stannous octoate, or dibutyltin dilaurate.

8. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The raw materials for preparing the polyurethane resin include the following components by weight: 60-70 parts of polyol, 2-8 parts of chain extender, 20-40 parts of isocyanate and 0.01-0.05 parts of catalyst.

9. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The raw materials for preparing the polyurethane resin also include organic solvents.

10. The antistatic polyurethane synthetic leather according to claim 9, characterized in that, The organic solvent includes any one or a combination of at least two of acetone, butanone, N,N-dimethylacetamide, or N,N-dimethylformamide.

11. The antistatic polyurethane synthetic leather according to claim 9, characterized in that, The organic solvent comprises 30% to 70% of the total mass of the polyol, chain extender, isocyanate, and catalyst.

12. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The acid mentioned in step (1) includes a nitric acid solution.

13. The antistatic polyurethane synthetic leather according to claim 12, characterized in that, The concentration of the nitric acid solution is 3~6 mol / L.

14. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, Step (1) specifically includes the following steps: (I) Dry the areca leaves, carbonize them, and grind them to obtain a fine black powder; (II) The black fine powder obtained in (I) is mixed with acid, heated and stirred under reflux, diluted, centrifuged and dried to obtain the areca leaf carbon nanospheres.

15. The antistatic polyurethane synthetic leather according to claim 14, characterized in that, The drying temperature in step (I) is 40~80℃, and the drying time is 2~6 h.

16. The antistatic polyurethane synthetic leather according to claim 14, characterized in that, The carbonization described in step (I) is carried out in a tubular furnace or a muffle furnace.

17. The antistatic polyurethane synthetic leather according to claim 14, characterized in that, The carbonization temperature in step (I) is 300~500℃, and the carbonization time is 10~18 h.

18. The antistatic polyurethane synthetic leather according to claim 14, characterized in that, The grinding time in step (I) is 3-5 hours.

19. The antistatic polyurethane synthetic leather according to claim 14, characterized in that, The heating, stirring, and refluxing temperature in step (II) is 80~120℃, and the time is 10~16 h.

20. The antistatic polyurethane synthetic leather according to claim 14, characterized in that, In step (II), the centrifugation speed is 3000~5000 r / min, and the centrifugation time is 15~30 min.

21. The antistatic polyurethane synthetic leather according to claim 14, characterized in that, The drying temperature in step (II) is 60~90℃, and the drying time is 6~10 h.

22. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, Step (2) specifically includes the following steps: mixing polyol, chain extender and organic solvent, adding isocyanate, reacting for the first time, adding catalyst, reacting for the second time, to obtain polyurethane resin.

23. The antistatic polyurethane synthetic leather according to claim 22, characterized in that, The first and second reactions were carried out under the protection of an inert gas.

24. The antistatic polyurethane synthetic leather according to claim 22, characterized in that, The temperatures for the first and second reactions are each independently between 65 and 85°C.

25. The antistatic polyurethane synthetic leather according to claim 22, characterized in that, The first reaction takes 6 to 10 hours.

26. The antistatic polyurethane synthetic leather according to claim 22, characterized in that, The second reaction takes 4 to 8 hours.

27. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The ultrasonic power in step (3) is 500~1000W, and the ultrasonic time is 15~40 min.

28. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The mass ratio of areca leaf carbon nanospheres to solvent in step (3) is 1:3 to 1:

6.

29. The antistatic polyurethane synthetic leather according to claim 1, characterized in that, The mixing in step (3) includes stirring and mixing for a period of 1 to 3 hours.

30. A method for preparing antistatic polyurethane synthetic leather according to any one of claims 1-29, characterized in that, The preparation method includes the following steps: (a) Coating the surface of release paper with antistatic polyurethane resin and drying it to obtain a polyurethane resin layer; (b) The surface of the polyurethane resin layer obtained in step (a) is coated with an adhesive, the base fabric is bonded, dried, and the release paper is removed to obtain the antistatic polyurethane synthetic leather.

31. The preparation method according to claim 30, characterized in that, The coating thickness in step (a) is 0.5~2mm.

32. The preparation method according to claim 30, characterized in that, The drying temperature in step (a) is 80~100℃ and the time is 10~30 min.

33. The preparation method according to claim 30, characterized in that, The coating thickness in step (b) is 0.5~2mm.

34. The preparation method according to claim 30, characterized in that, The drying temperature in step (b) is 100~140℃ and the time is 20~40 min.

35. The preparation method according to claim 30, characterized in that, The base fabric includes microfiber base.