A polyurethane resin fiber composite material and a method for manufacturing and use thereof

Abstract

The application provides a polyurethane resin fiber composite material and a preparation method and application thereof, and belongs to the technical field of materials. Tea fiber and tea extract are extracted and obtained, the tea fiber is carbonized and then coated with multi-fold graphene oxide on the surface, reduced, and reacted with the tea extract, and then modified by phytic acid to obtain modified tea carbon fiber; modified cellulose is prepared by modifying maleic anhydride modified cellulose; the polyol, the modified tea carbon fiber, the modified cellulose, and modified TiO2 nanospheres are mixed, a catalyst, dimethyl methylphosphonate, and glycerol are added, and stirring is uniformly carried out, isocyanate is added, and after uniform mixing, solidification forming is carried out, so that the polyurethane resin fiber composite material is obtained, has good mechanical properties and degradable properties, good antibacterial properties and environmental protection, good antistatic and flame retardant properties, realizes resource utilization of tea residues, has low cost, the preparation method is simple, and has a wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of materials technology, specifically to a polyurethane resin fiber composite material, its preparation method, and its application. Background Technology

[0002] Although existing technologies have extracted cellulose from some tea leaves to prepare tea fiber materials, such methods only utilize the cellulose component and fail to make high-value utilization of bioactive substances such as tea polyphenols and residual carbon. The resource utilization rate is low and the added value of the product is limited.

[0003] Polyurethane (PU) materials have become indispensable polymer materials in automotive interiors, electronics, packaging materials, and building insulation due to their highly designable molecular structure, excellent mechanical properties (wear resistance 5-10 times higher than natural rubber), good adhesion, and adaptability to various substrates. However, with increasing demands from application end users for material safety, environmental friendliness, and functional versatility, traditional polyurethane materials have revealed the following technical bottlenecks: 1. Safety Performance Defects: Flammability and Static Electricity Accumulation Risks. Polyurethane's main chain contains a large amount of flammable hydrocarbon structures, classifying it as a flammable material. Combustion is accompanied by dripping and releases large amounts of toxic fumes (HCN, CO), severely limiting its application in fields with stringent flame-retardant requirements, such as transportation and electronic packaging. Simultaneously, polyurethane has a high volume resistivity, making it extremely prone to static electricity accumulation during use. Surface static voltage can reach thousands of volts, not only attracting dust and affecting appearance but also posing a safety hazard of fire and explosion caused by electrostatic discharge. Existing technologies often improve this by simply blending and adding phosphate ester flame retardants or conductive carbon black. However, flame retardants and antistatic agents often interfere with each other (e.g., carbon black promotes combustion, while flame retardants increase insulation), making it difficult to simultaneously improve flame-retardant and antistatic properties.

[0004] 2. The contradiction between mechanical properties and functionality. To impart antibacterial and UV-resistant functions to polyurethane, inorganic nanoparticles such as TiO2 and ZnO or natural antibacterial agents are usually added. However, these polar functional fillers have poor interfacial compatibility with the hydrophobic polyurethane matrix, easily leading to agglomeration and stress concentration, resulting in deterioration of mechanical properties such as reduced tensile strength and elongation at break. Existing surface modification techniques (such as silane coupling agent treatment) can improve dispersibility, but lack a chemical bonding mechanism with the polyurethane matrix, making the interface prone to debonding under dynamic loads or humid and hot environments, resulting in insufficient functional durability.

[0005] 3. Dependence on Petroleum-Based Raw Materials and Pressure for Sustainable Development. The polyol components of traditional polyurethanes are mainly derived from petrochemical products (polyether polyols, polyester polyols). Although biomass-based polyols (such as castor oil-based and soybean oil-based) have been studied, they suffer from high raw material costs and large performance fluctuations. Utilizing agricultural waste (such as tea residue) to extract fibers and bioactive components as reinforcing phases and functional additives for polyurethanes is an effective way to reduce costs and improve environmental friendliness. However, current technologies for utilizing tea residue are limited to simple crushing and filling, failing to achieve the graded extraction and targeted conversion of components such as cellulose, tea polyphenols, and lignin. This results in low reinforcement efficiency and uncontrollable functional release, while also hindering the improvement of the biodegradability of polyurethane materials.

[0006] Therefore, developing a composite material with polyurethane as the matrix, which achieves synergistic improvement in flame retardancy, antibacterial properties, antistatic properties, and mechanical properties through the high-value utilization of all components of biomass resources and the functional modification of filler surfaces, is of great significance for expanding the application of polyurethane in high-end safety fields and promoting the industrialization of bio-based materials. Summary of the Invention

[0007] The purpose of this invention is to propose a polyurethane resin fiber composite material, its preparation method, and its application. Addressing the problems in existing technologies such as low resource utilization rate of tea residue, difficulty in simultaneously achieving mechanical properties and functionalities (antibacterial properties, photo-aging resistance, etc.) of polyurethane materials, weak interfacial bonding and poor dispersibility between inorganic fillers and organic matrices, poor water resistance and processing stability of biomass composite materials, and poor biodegradability of polyurethane materials, the resulting polyurethane resin fiber composite material exhibits good mechanical properties and biodegradability, good antibacterial and environmental friendliness, and good antistatic, antibacterial, UV-resistant, and flame-retardant properties. It realizes the resource utilization of tea residue, with low cost, a simple preparation method, and broad application prospects.

[0008] The technical solution of this invention is implemented as follows: This invention provides a method for preparing a polyurethane resin fiber composite material. The method involves extracting tea fiber and tea extract, carbonizing the tea fiber and then coating its surface with multi-folded graphene oxide, reducing it, reacting it with the tea extract, and then modifying it with phytic acid to obtain modified tea carbon fiber. Maleic anhydride is used to modify cellulose to obtain modified cellulose. Polyol, modified tea carbon fiber, modified cellulose, and modified TiO2 nanospheres are mixed, and a catalyst, dimethyl methylphosphonate, and glycerol are added. The mixture is stirred and mixed evenly, isocyanate is added, and after even mixing, it is cured and molded to obtain the polyurethane resin fiber composite material.

[0009] As a further improvement to the present invention, the following steps are included: S1. Processing of tea residue: Tea residue is added to an ethanol solution, heated for extraction, filtered, and the filtrate is dried to obtain tea extract; the residue is added to water with sodium hypochlorite, stirred for reaction, filtered, and washed until neutral; the residue is then added to an acid solution, stirred for reaction, filtered, and washed until neutral; the residue is then added to ether, stirred for reaction, filtered, and washed with ether; the residue is then added to an alkaline solution, stirred for reaction, filtered, washed until neutral, and dried to obtain tea fiber; the tea fiber is then heated and carbonized to obtain tea carbon fiber. This invention utilizes the principle that ethanol has good solubility for tea polyphenols to extract active substances such as tea polyphenols from tea residue, obtaining a tea extract containing catechins, tea polyphenols, etc. Then, the residue undergoes multi-stage chemical treatment, including oxidation, acid washing, organic solvent washing, and alkali washing, to remove impurities such as lignin, pectin, and fat-soluble pigments from the tea residue, improving fiber purity and obtaining tea fiber. This fiber is then heated and carbonized to produce tea carbon fiber, which improves antistatic effects, greatly increases the utilization rate of tea residue, realizes its resource utilization, reduces waste generation, and prepares composite materials, thereby increasing its economic value.

[0010] S2. Coating of tea extract / polypleated graphene: Graphene oxide is dispersed in water, tea carbon fibers are added, stirred and mixed evenly, and spray dried to obtain polypleated graphene oxide coated tea carbon fibers. After reduction by hydrazine hydrate vapor, the product is added to ethanol, tea extract is added, the reaction is stirred, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fibers. Tea carbon fibers are coated with graphene oxide and spray-dried for rapid water loss, forming a multi-folded structure. This effectively reduces the stacking of the graphene oxide inclusion complex in the polymer matrix, avoiding agglomeration and achieving uniform dispersion. After reduction with hydrazine hydrate, a graphene network is obtained, which facilitates the formation of a carbon network and improves the antistatic properties of the material. The resulting graphene inclusion complex, through its multi-folded structure, allows tea polyphenols and other substances to be loaded onto it, greatly improving the antibacterial properties of the material. The multi-folded structure increases the specific surface area, thereby increasing the loading capacity of tea polyphenols and other substances.

[0011] S3. Phytic acid modification: Tea extract / pleated graphene-coated tea carbon fiber and phytic acid were added to water, dipotassium hydrogen phosphate was added, hydrothermal reaction was carried out, centrifuged, washed, and dried to obtain modified tea carbon fiber. This invention further processes the prepared tea extract / polypleated graphene-coated tea carbon fiber with phytic acid to construct a "core-shell" structure, thereby forming a halogen-free flame-retardant system of tea carbon fiber (carbon source) + phytic acid (acid source) + pyrolysis components of tea extract (gas source). The tea carbon fiber provides carbon skeleton support and reacts with phytic acid to form a cross-linked carbon layer. The multipleated surface structure enhances the gas expansion effect. The tea carbon fiber decomposes to generate carbon, which, together with the pyrolysis components of tea extract (gas), forms an expanding porous carbon layer. The release of pyrolysis gas from the tea extract is synchronized with the formation of the carbon layer, forming a honeycomb-like expanding structure. The residual carbon of the pyrolysis components of tea extract participates in the reinforcement of the carbon layer. The three work synergistically to have an excellent flame-retardant effect.

[0012] S4. Preparation of modified cellulose: Add cellulose to a solvent, add maleic anhydride, heat under reflux to react, filter, wash, and dry to obtain modified cellulose; This invention modifies maleic anhydride with cellulose, thereby reducing the polarity of cellulose, introducing carboxyl groups and double bonds, which can react with isocyanates to form a crosslinking network, increasing the crosslinking density of polyurethane, and improving the dispersion uniformity of modified cellulose in polyurethane. The resulting composite material has significantly improved mechanical properties and further improved biodegradability.

[0013] S5. Preparation of modified TiO2 nanospheres: Tetrabutyl titanate and thiourea were added to an organic solvent to obtain an oil phase; an emulsifier was dissolved in water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified, stirred, centrifuged, washed, and dried to obtain doped nanospheres; the doped nanospheres were added to ethanol, a silane coupling agent was added, heated and stirred, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; The modified TiO2 nanospheres prepared in this invention are first prepared by sol-gel reaction, where S / N-doped TiO2 nanospheres are formed. The doping of S and N replaces the O atoms in the TiO2 lattice, reducing the band gap of TiO2 and causing the absorption edge to redshift into the visible light region. This band shrinkage allows electrons to transition from the valence band to the conduction band under visible light excitation, enabling catalytic reactions in the visible light region. Furthermore, the surface of the prepared doped nanospheres is modified with an amino-containing silane coupling agent, allowing the modified TiO2 nanospheres to be uniformly dispersed in a polyurethane matrix system. This improves the material's compatibility, facilitates the photocatalytic decomposition of organic compounds such as formaldehyde, promotes the degradation of composite materials, and also exhibits good ultraviolet shielding efficiency, improving the composite material's resistance to photoaging, antibacterial properties, and environmental friendliness.

[0014] S6. Preparation of polyurethane resin fiber composite material: Polyol, modified carbon fiber, modified cellulose, and modified TiO2 nanospheres are mixed, and catalyst, dimethyl methylphosphonate and glycerol are added. The mixture is stirred and mixed evenly, isocyanate is added, and after being mixed evenly, it is cured and molded to obtain polyurethane resin fiber composite material.

[0015] The polyurethane resin fiber composite material prepared by this invention has good mechanical properties and biodegradability, good antibacterial and environmental protection properties, good antistatic and flame retardant properties, realizes the resource utilization of tea residue, and has low cost, simple preparation method, and broad application prospects.

[0016] As a further improvement of the present invention, the mass ratio of tea residue and sodium hypochlorite in step S1 is 10:5-7, the heating extraction temperature is 80-90℃ and the time is 1-3h, the acid solution is 1-2wt% hydrochloric acid or sulfuric acid solution, the alkaline solution is 2-5wt% NaOH or KOH solution, and the heating carbonization temperature is 550-750℃ and the time is 1-3h.

[0017] As a further improvement of the present invention, the mass ratio of graphene oxide to tea carbon fiber in step S2 is 7-10:5-7, the time for hydrazine hydrate vapor reduction is 8-10h, the mass ratio of multi-fold graphene oxide-coated tea carbon fiber to tea extract is 10-15:4-5, and the stirring reaction time is 20-40min.

[0018] As a further improvement of the present invention, the mass ratio of tea extract / poly-plastered graphene-coated tea carbon fiber, phytic acid and dipotassium hydrogen phosphate in step S3 is 10-15:4-7:0.2-0.5, the hydrothermal reaction temperature is 120-140℃, and the time is 7-10h.

[0019] As a further improvement of the present invention, the mass ratio of cellulose to maleic anhydride in step S4 is 10:2-3, the solvent is a mixed solvent of acetone and water with a volume ratio of 7-10:2-4, and the heating and reflux reaction time is 2-4 hours.

[0020] As a further improvement of the present invention, the mass ratio of tetrabutyl titanate, thiourea, and emulsifier in step S5 is 10-12:1-2:0.5-1, the emulsifier is selected from at least one of Tween-20, Tween-40, Tween-60, Tween-80, and Tween-85, the mass ratio of doped nanospheres and silane coupling agent is 10:2.2-3.5, the silane coupling agent is selected from at least one of KH550, KH602, and KH792, and the heating and stirring reaction temperature is 40-50°C, and the time is 1-3 hours.

[0021] As a further improvement of the present invention, the polyol in step S6 is a polyether polyol, the catalyst is dibutyltin dilaurate, and the isocyanate is selected from at least one of polyphenyl polymethylene polyisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, aliphatic isocyanate, naphthalene 1,5-diisocyanate, phenylenediamine diisocyanate, and tetramethyl isophthalimethylene diisocyanate. The mass ratio of the polyol, modified tea carbon fiber, modified cellulose, modified TiO2 nanospheres, catalyst, dimethyl methylphosphonate, glycerol, and isocyanate is 100:6-8:4-6:3-5:0.2-0.5:8-12:2-5:60-65.

[0022] The present invention further protects a polyurethane resin fiber composite material prepared by the above-described preparation method.

[0023] This invention further protects the application of the above-mentioned polyurethane resin fiber composite material in the preparation of automotive interior trim.

[0024] The present invention has the following beneficial effects: 1. This invention overcomes the problem of high brittleness of traditional biomass-filled polyurethane by introducing carboxyl groups and double bonds into maleic anhydride-modified cellulose and forming a chemical cross-linking network with amino groups on the surface of modified TiO2 nanospheres, and combining modified tea carbon fiber (multi-folded graphene coating + phytic acid interface bridging) with modified TiO2 nanospheres to synergistically enhance the mechanical properties of the material at the micro and nano scales.

[0025] 2. This invention utilizes phytic acid (acid source / catalyst) to catalyze the dehydration of tea carbon fiber (carbon source) and polyurethane matrix to form carbon, and synergistically uses dimethyl methylphosphonate (gas source) to release non-flammable gas to form an expanded carbon layer, thus constructing a highly efficient expanded flame retardant network, which significantly improves the flame retardancy of the material. Moreover, it does not contain any halogens, avoiding the release of toxic hydrogen halide gas during combustion, and meets the environmental protection and flame retardant requirements of electronic appliances and automotive interiors.

[0026] 3. This invention utilizes the reduction of hydrazine hydrate to form a tea carbon fiber / pleated graphene coating structure, which constructs an effective three-dimensional conductive network within a polyurethane matrix. This significantly improves the antistatic properties of the material and effectively prevents static electricity buildup. Slow-release antibacterial effects are achieved by loading tea extracts (including tea polyphenols, catechins, etc.) into the pleated graphene interlayer. Thiourea-doped TiO2 nanospheres generate ROS photocatalytic sterilization under visible light. The combined effect of these two components synergistically improves the antibacterial properties of the material, resulting in long-lasting antibacterial activity.

[0027] 4. This invention improves the degradation rate of composite materials by synergistically combining the photocatalytic activity of sulfur-doped TiO2 nanospheres with the degradability of tea carbon fibers and modified cellulose. Combined with the multiple utilization of tea residue raw materials, it achieves the unity of agricultural waste resource utilization and material life cycle environmental friendliness.

[0028] 5. Natural fibers are prone to moisture absorption, leading to poor material dimensional stability and easy interface hydrolysis. This invention reduces the material's water absorption rate and improves its performance retention in humid and hot environments through carbonization treatment (improving hydrophobicity), hydrophobic modification (ether washing to remove polar impurities), and cross-linking network construction (maleic anhydride introducing double bonds to participate in polyurethane curing). Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a SEM image of the tea extract / polypleated graphene-coated tea carbon fiber prepared in Example 1.

[0031] Figure 2 The image shows the infrared spectrum of the modified tea carbon fiber prepared in Example 1.

[0032] Figure 3 This is a SEM image of the modified TiO2 nanospheres prepared in Example 1.

[0033] Figure 4 The image shows the XRD pattern of the polyurethane resin fiber composite material prepared in Example 1. Detailed Implementation

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Graphene oxide, number of layers <5, content >99%, particle size <5μm; cellulose powder, TREVA™ GC6021 Clear, Eastman Chemical Company, USA.

[0036] Example 1 This embodiment provides a method for preparing a polyurethane resin fiber composite material, including the following steps: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 90℃ for 1h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 5g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered and washed with ether. The residue was then added to 2wt% NaOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 550℃ and carbonized for 1h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 140 mg of graphene oxide was dispersed in 200 mL of water, 100 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide coated tea carbon fiber. 200 mg of polypleated graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 8 h. The product was added to 100 mL of ethanol, 80 mg of tea extract was added, the mixture was stirred for 20 min, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fiber. Figure 2 SEM image of the prepared tea extract / pleated graphene-coated tea carbon fiber.

[0037] S3. Modification of phytic acid: 100 mg of tea extract / polypleated graphene-coated tea carbon fiber and 40 mg of phytic acid were added to 100 mL of water, 2 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 120 °C, and the hydrothermal reaction was carried out for 7 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. Figure 2 Infrared spectrum of the modified tea carbon fiber prepared.

[0038] S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2g of maleic anhydride was added, the mixture was heated and stirred under reflux for 2h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 7:2; S5. Preparation of modified TiO2 nanospheres: 10g tetrabutyl titanate and 1g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1g Tween-40 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 2.2g silane coupling agent KH792 was added, heated to 40℃, stirred for 1h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; Figure 3 SEM image of the prepared modified TiO2 nanospheres.

[0039] S6. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 6g of modified carbon fiber, 4g of modified cellulose, and 3g of modified TiO2 nanospheres were mixed and stirred for 1 min. Then, 0.2g of dibutyltin dilaurate, 8g of dimethyl methylphosphonate, and 2g of glycerol were added and stirred until uniform. Finally, 60g of polyphenylene polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured to obtain polyurethane resin fiber composite material. Figure 4 The image shows the XRD pattern of the polyurethane resin fiber composite material.

[0040] Example 2 This embodiment provides a method for preparing a polyurethane resin fiber composite material, including the following steps: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 80℃ for 3h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 7g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 2wt% sulfuric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered and washed with ether. The residue was then added to 5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 750℃ and carbonized for 3h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 200 mg of graphene oxide was dispersed in 200 mL of water, 140 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide coated tea carbon fiber. 300 mg of polypleated graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 10 h. The product was added to 100 mL of ethanol, 100 mg of tea extract was added, the mixture was stirred for 40 min, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fiber. S3. Phytic acid modification: 150 mg of tea extract / polypleated graphene-coated tea carbon fiber and 70 mg of phytic acid were added to 100 mL of water, 5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 140 °C, and the hydrothermal reaction was carried out for 10 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 3g of maleic anhydride was added, the mixture was heated and stirred under reflux for 4h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 10:4; S5. Preparation of modified TiO2 nanospheres: 12g tetrabutyl titanate and 2g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 2g Tween-60 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3.5g silane coupling agent KH602 was added, heated to 50℃, stirred for 3h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S6. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 8g of modified carbon fiber, 6g of modified cellulose, and 5g of modified TiO2 nanospheres were mixed and stirred for 1 min. Then, 0.5g of dibutyltin dilaurate, 12g of dimethyl methylphosphonate, and 5g of glycerol were added and stirred until uniform. Finally, 65g of polyphenylene polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured to obtain polyurethane resin fiber composite material.

[0041] Example 3 This embodiment provides a method for preparing a polyurethane resin fiber composite material, including the following steps: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide coated tea carbon fiber. 250 mg of polypleated graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 9 h. The product was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred for 30 min, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fiber. S3. Modification of phytic acid: 125 mg of tea extract / polypleated graphene-coated tea carbon fiber and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S5. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3g silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S6. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, 5g of modified cellulose, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. Then, 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. Finally, 62g of polyphenylene polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured and shaped to obtain the polyurethane resin fiber composite material.

[0042] Comparative Example 1 The difference from Example 3 is that tea extract was not added in step S2.

[0043] Specifically as follows: S1. Processing of tea residue: 10g of tea residue and 6g of sodium hypochlorite were added to 200mL of water and stirred for 2 hours. The mixture was then filtered and washed until neutral. The residue was then added to a 1.5wt% hydrochloric acid solution and stirred for 1 hour. The mixture was then filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1 hour. The mixture was then filtered and washed with ether. The residue was then added to a 3.5wt% KOH solution and stirred for 1 hour. The mixture was then filtered and washed until neutral. The residue was dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2 hours to obtain tea carbon fiber. S2. Coating of polypleated graphene oxide: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, spray dried, and the product was reduced by hydrazine hydrate vapor for 9 h to obtain polypleated graphene coated tea carbon fiber. S3. Modification of phytic acid: 125 mg of multi-folded graphene-coated tea carbon fiber and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S5. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3g silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S6. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, 5g of modified cellulose, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. Then, 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. Finally, 62g of polyphenylene polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured and shaped to obtain the polyurethane resin fiber composite material.

[0044] Comparative Example 2 The difference from Example 3 is that graphene oxide was not added in step S2.

[0045] Specifically as follows: S2. Coating with tea polyphenols: 250 mg of tea carbon fiber was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred and reacted for 30 min, centrifuged, washed, and dried to obtain tea polyphenol-coated tea carbon fiber.

[0046] S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Mixing: Add 250mg of tea carbon fiber to 100mL of ethanol, add 90mg of tea extract, stir and react for 30min, centrifuge, wash, dry, and obtain a tea extract / tea carbon fiber mixture; S3. Modification of phytic acid: 125 mg of tea extract / tea carbon fiber mixture and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, modified tea carbon fiber was obtained. S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S5. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3g silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S6. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, 5g of modified cellulose, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. Then, 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. Finally, 62g of polyphenylene polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured and shaped to obtain the polyurethane resin fiber composite material.

[0047] Comparative Example 3 The difference from Example 3 is that spray drying in step S2 is replaced by conventional drying.

[0048] Specifically as follows: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and dried at 105 °C to constant weight to obtain graphene oxide coated tea carbon fiber. 250 mg of graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 9 h. The product was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred for 30 min, centrifuged, washed, and dried to obtain tea extract / graphene coated tea carbon fiber. S3. Modification of phytic acid: 125 mg of tea extract / graphene-coated tea carbon fiber and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S5. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3g silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S6. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, 5g of modified cellulose, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. Then, 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. Finally, 62g of polyphenylene polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured and shaped to obtain the polyurethane resin fiber composite material.

[0049] Comparative Example 4 The difference from Example 3 is that step S3 was not performed.

[0050] Specifically as follows: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Coating with tea extract / polypleated graphene: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide-coated tea carbon fiber. 250 mg of polypleated graphene oxide-coated tea carbon fiber was reduced by hydrazine hydrate vapor for 9 h. The product was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred for 30 min, centrifuged, washed, and dried to obtain modified tea carbon fiber. S3. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S4. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3g silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S5. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, 5g of modified cellulose, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. 62g of polyphenylene polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured to obtain polyurethane resin fiber composite material.

[0051] Comparative Example 5 Compared with Example 3, the difference is that step S5 was not performed, and the modified cellulose in step S7 was replaced by cellulose powder.

[0052] Specifically as follows: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide coated tea carbon fiber. 250 mg of polypleated graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 9 h. The product was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred for 30 min, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fiber. S3. Modification of phytic acid: 125 mg of tea extract / polypleated graphene-coated tea carbon fiber and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3g silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S5. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, 5g of cellulose, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. 62g of polyphenyl polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured to obtain polyurethane resin fiber composite material.

[0053] Comparative Example 6 The difference from Example 3 is that thiourea was not added in step S6.

[0054] Specifically as follows: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide coated tea carbon fiber. 250 mg of polypleated graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 9 h. The product was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred for 30 min, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fiber. S3. Modification of phytic acid: 125 mg of tea extract / polypleated graphene-coated tea carbon fiber and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S5. Preparation of modified TiO2 nanospheres: 12.5g tetrabutyl titanate was added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain nanospheres; 10g of nanospheres were added to 200mL ethanol, 3g of silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S6. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, 5g of modified cellulose, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. Then, 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. Finally, 62g of polyphenylene polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured and shaped to obtain the polyurethane resin fiber composite material.

[0055] Comparative Example 7 The difference from Example 3 is that the silane coupling agent KH550 was not modified in step S6.

[0056] Specifically as follows: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide coated tea carbon fiber. 250 mg of polypleated graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 9 h. The product was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred for 30 min, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fiber. S3. Modification of phytic acid: 125 mg of tea extract / polypleated graphene-coated tea carbon fiber and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S5. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; S6. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, 5g of modified cellulose, and 4g of doped nanospheres were mixed and stirred for 1 min. Then, 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. Finally, 62g of polyphenyl polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured to obtain polyurethane resin fiber composite material.

[0057] Comparative Example 8 The difference from Example 3 is that no modified TiO2 nanospheres were added in step S7.

[0058] Specifically as follows: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide coated tea carbon fiber. 250 mg of polypleated graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 9 h. The product was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred for 30 min, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fiber. S3. Modification of phytic acid: 125 mg of tea extract / polypleated graphene-coated tea carbon fiber and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S5. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, and 5g of modified cellulose were mixed and stirred for 1 min. 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. 62g of polyphenyl polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured to obtain polyurethane resin fiber composite material.

[0059] Comparative Example 9 The difference from Example 3 is that no modified tea carbon fiber was added in step S7.

[0060] Specifically as follows: S1. Preparation of modified cellulose: 10g of cellulose powder was added to 100mL of solvent, 2.5g of maleic anhydride was added, the mixture was heated and stirred under reflux for 3h, filtered, washed, and dried to obtain modified cellulose; The solvent is a mixture of acetone and water in a volume ratio of 8:3; S2. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3g silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S3. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 5g of modified cellulose, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. Then, 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. Finally, 62g of polyphenyl polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured to obtain polyurethane resin fiber composite material.

[0061] Comparative Example 10 The difference from Example 3 is that no modified cellulose was added in step S7.

[0062] Specifically as follows: S1. Processing of tea residue: 10g of tea residue was added to 100mL of 80% ethanol solution, and extracted by refluxing at 85℃ for 2h using a Soxhlet extractor. The residue was filtered, and the filtrate was dried to obtain tea extract. The residue was then added to 200mL of water with 6g of sodium hypochlorite and stirred for 2h. The mixture was filtered and washed until neutral. The residue was then added to 1.5wt% hydrochloric acid solution and stirred for 1h. The mixture was filtered and washed until neutral. The residue was then added to 200mL of ether and stirred for 1h. The mixture was filtered, and the residue was washed with ether. The residue was then added to 3.5wt% KOH solution and stirred for 1h. The mixture was filtered, washed until neutral, and dried to obtain tea fiber. The tea fiber was then heated to 650℃ and carbonized for 2h to obtain tea carbon fiber. S2. Coating of tea extract / polypleated graphene: 170 mg of graphene oxide was dispersed in 200 mL of water, 120 mg of tea carbon fiber was added, the mixture was stirred for 15 min, and spray dried to obtain polypleated graphene oxide coated tea carbon fiber. 250 mg of polypleated graphene oxide coated tea carbon fiber was reduced by hydrazine hydrate vapor for 9 h. The product was added to 100 mL of ethanol, 90 mg of tea extract was added, the mixture was stirred for 30 min, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fiber. S3. Modification of phytic acid: 125 mg of tea extract / polypleated graphene-coated tea carbon fiber and 55 mg of phytic acid were added to 100 mL of water, 3.5 mg of dipotassium hydrogen phosphate was added, the mixture was heated to 130 °C, and the hydrothermal reaction was carried out for 8 h. After centrifugation, washing and drying, the modified tea carbon fiber was obtained. S4. Preparation of modified TiO2 nanospheres: 11g tetrabutyl titanate and 1.5g thiourea were added to 200mL ethyl acetate to obtain an oil phase; 1.5g Tween-85 was dissolved in 100mL water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified at 8000r / min for 15min, stirred for 2h, centrifuged, washed, and dried to obtain doped nanospheres; 10g of doped nanospheres were added to 200mL ethanol, 3g silane coupling agent KH550 was added, heated to 45℃, stirred for 2h, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; S5. Preparation of polyurethane resin fiber composite material: 100g of polyether polyol N330 (Mn=3000), 7g of modified carbon fiber, and 4g of modified TiO2 nanospheres were mixed and stirred for 1 min. 0.3g of dibutyltin dilaurate, 10g of dimethyl methylphosphonate, and 3g of glycerol were added and stirred until uniform. 62g of polyphenyl polymethylene polyisocyanate was added and stirred until uniform. The mixture was then cured to obtain polyurethane resin fiber composite material.

[0063] Test Example 1 The mechanical properties of the materials prepared in Examples 1-3 and Comparative Examples 1-10 of the present invention were tested, and the results are shown in Table 1.

[0064] Tensile strength (MPa) and elongation at break (%) were tested in accordance with ASTM D-638-22, "Standard Test Methods for Tensile Properties of Plastics".

[0065] Notched impact strength (kJ / m) 2 The test was conducted in accordance with the standard ASTM D-256-24, "Standard Test Method for Impact Strength of Plastic Cantilever Beam Pendulum (Izod Impact Test)".

[0066] Table 1 ; As can be seen from the table above, the polyurethane resin fiber composite materials prepared in Examples 1-3 of the present invention have good mechanical properties.

[0067] Test Example 2 The materials prepared in Examples 1-3 and Comparative Examples 1-9 of this invention were subjected to comprehensive performance tests, and the results are shown in Table 2.

[0068] Water absorption rate (%): Tested according to ASTM D-570-22, "Standard Test Method for Water Absorption of Plastics".

[0069] Vertical burning test (UL94): The test was conducted in accordance with standard GB / T 2408-2021, with a sample size of 130×13×3mm. 3 .

[0070] Antibacterial rate (%): Tested according to the test method of standard GB21551.2-2010. Detection bacteria: Escherichia coli (AATCC8099).

[0071] Volume resistivity (Ω·m): Tested according to ASTM D-257-14(2021)e1 "Standard Test Method for DC Resistance or Conductivity of Insulating Materials", with a test temperature of 23℃ and a relative humidity of 50±5%.

[0072] Complete degradation time (d): The sample was cut into 1cm×1cm×2mm pieces and dried in a vacuum drying oven at 40℃ for 24h. The initial mass was then measured. The sample was then placed in a reagent bottle containing 50mL of PBS buffer (pH=7.4) and placed in a constant temperature and humidity chamber at 37℃ and 50% relative humidity. The solution was changed every 10 days. The sample was then removed, its surface moisture was wiped dry, and its mass was measured after thorough drying. The time (d) required for complete degradation was recorded.

[0073] Table 2 ; As shown in the table above, the polyurethane resin fiber composite materials prepared in Examples 1-3 of the present invention have good flame retardant, antibacterial, and antistatic properties, and low water absorption.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a polyurethane resin fiber composite material, characterized in that, Includes the following steps: S1. Processing of tea residue: Tea residue is added to ethanol, heated and stirred for extraction, filtered, and the filtrate is dried to obtain tea extract; the residue is added to water with sodium hypochlorite, stirred for reaction, filtered, and washed until neutral; the residue is then added to acid solution, stirred for reaction, filtered, and washed until neutral; the residue is then added to ether, stirred for reaction, filtered, and washed with ether; the residue is then added to alkaline solution, stirred for reaction, filtered, washed until neutral, and dried to obtain tea fiber; the tea fiber is then heated and carbonized to obtain tea carbon fiber; the mass ratio of tea residue to sodium hypochlorite is 10:5-7; S2. Coating of tea extract / polypleated graphene: Graphene oxide is dispersed in water, tea carbon fibers are added, stirred and mixed evenly, and spray-dried to obtain polypleated graphene oxide coated tea carbon fibers. After reduction by hydrazine hydrate vapor, the product is added to ethanol, tea extract is added, the reaction is stirred, centrifuged, washed, and dried to obtain tea extract / polypleated graphene coated tea carbon fibers; the mass ratio of graphene oxide to tea carbon fibers is 7-10:5-7; the mass ratio of polypleated graphene oxide coated tea carbon fibers to tea extract is 10-15:4-5. S3. Modification of phytic acid: Tea extract / poly-plastic graphene-coated tea carbon fiber and phytic acid were added to water, dipotassium hydrogen phosphate was added, hydrothermal reaction was carried out, centrifuged, washed, and dried to obtain modified tea carbon fiber; the mass ratio of tea extract / poly-plastic graphene-coated tea carbon fiber, phytic acid and dipotassium hydrogen phosphate was 10-15:4-7:0.2-0.

5. S4. Preparation of modified cellulose: cellulose is added to a solvent, maleic anhydride is added, the mixture is heated under reflux, filtered, washed, and dried to obtain modified cellulose; the mass ratio of cellulose to maleic anhydride is 10:2-3; S5. Preparation of modified TiO2 nanospheres: Tetrabutyl titanate and thiourea were added to an organic solvent to obtain an oil phase; an emulsifier was dissolved in water to obtain an aqueous phase; the aqueous phase was added dropwise to the oil phase, emulsified, stirred, centrifuged, washed, and dried to obtain doped nanospheres; the doped nanospheres were added to ethanol, a silane coupling agent was added, heated and stirred, centrifuged, washed, and dried to obtain modified TiO2 nanospheres; the mass ratio of tetrabutyl titanate, thiourea, and emulsifier was 10-12:1-2:0.5-1; S6. Preparation of polyurethane resin fiber composite material: Polyol, modified carbon fiber, modified cellulose, and modified TiO2 nanospheres are mixed, and a catalyst, dimethyl methylphosphonate, and glycerol are added. The mixture is stirred and mixed evenly, and then isocyanate is added. After mixing evenly, the mixture is cured and molded to obtain polyurethane resin fiber composite material. The polyol is a polyether polyol, and the catalyst is dibutyltin dilaurate. The mass ratio of the polyol, modified carbon fiber, modified cellulose, modified TiO2 nanospheres, catalyst, dimethyl methylphosphonate, glycerol, and isocyanate is 100:6-8:4-6:3-5:0.2-0.5:8-12:2-5:60-65.

2. The preparation method according to claim 1, characterized in that, In step S1, the heating extraction temperature is 80-90℃ and the time is 1-3h. The acid solution is 1-2wt% hydrochloric acid or sulfuric acid solution, the alkaline solution is 2-5wt% NaOH or KOH solution, and the heating carbonization temperature is 550-750℃ and the time is 1-3h.

3. The preparation method according to claim 1, characterized in that, The time for the hydrazine hydrate vapor reduction in step S2 is 8-10 hours, and the time for the stirring reaction is 20-40 minutes.

4. The preparation method according to claim 1, characterized in that, The hydrothermal reaction in step S3 is carried out at a temperature of 120-140℃ for 7-10 hours.

5. The preparation method according to claim 1, characterized in that, The solvent in step S4 is a mixture of acetone and water in a volume ratio of 7-10:2-4, and the heating and reflux reaction time is 2-4 hours.

6. The preparation method according to claim 1, characterized in that, In step S5, the emulsifier is selected from at least one of Tween-20, Tween-40, Tween-60, Tween-80, and Tween-85. The mass ratio of the doped nanospheres to the silane coupling agent is 10:2.2-3.

5. The silane coupling agent is selected from at least one of KH550, KH602, and KH792. The heating and stirring reaction is carried out at a temperature of 40-50°C for 1-3 hours.

7. The preparation method according to claim 1, characterized in that, The isocyanate mentioned in step S6 is selected from at least one of polyphenyl polymethylene polyisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, aliphatic isocyanate, naphthalene 1,5-diisocyanate, phenylmethylene diisocyanate, and tetramethyl isophenylmethylene diisocyanate.

8. A polyurethane resin fiber composite material prepared by the preparation method according to any one of claims 1-7.

9. The application of a polyurethane resin fiber composite material as described in claim 8 in automotive interiors.

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