Wear-resistant polyurethane material and preparation method thereof

Abstract

The invention provides a wear-resistant polyurethane material and a preparation method thereof, and belongs to the technical field of polyurethane. Comprising a component A and a component B. The component A comprises the following raw materials in parts by weight: 102-120 parts of polyether polyol, 6-10 parts of a chain extender, 0.05-0.1 part of a catalyst, 0.3-0.5 part of an antioxidant, 5-10 parts of a wear-resistant reinforcing agent, 0.04-0.06 part of silicone oil and 0.3-0.5 part of an ultraviolet light absorber. The component B is prepared from the following raw materials in parts by weight: 35 to 45 parts of polyisocyanate, 0.02 to 0.04 part of polymerization inhibitor and 70 to 89 parts of polyether. By adding the special wear-resistant reinforcing agent and optimizing the preparation process, the wear resistance is excellent, the flame retardance, the strength, the toughness and the chemical corrosion resistance are higher, and good economic benefits and market application prospects are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of polyurethanes, and particularly relates to a wear-resistant polyurethane material and a preparation method thereof. Background Art

[0002] Due to its good mechanical properties, chemical corrosion resistance and processing properties, polyurethane materials are widely used in many fields. However, traditional polyurethane materials have certain deficiencies in wear resistance and are difficult to meet the usage requirements under some high-wear working conditions. At present, the methods for improving the wear resistance of polyurethane materials mainly include adding wear-resistant fillers, optimizing the molecular structure, etc. However, these methods have problems such as limited addition amount and easy influence on other properties of the materials, and it is impossible to effectively prepare a polyurethane material with both excellent wear resistance and other properties. Therefore, it is urgent to develop a new super wear-resistant polyurethane material.

[0003] Chinese invention patent CN103254387B discloses a high wear-resistant polyurethane elastomer and a preparation method thereof. By adding ultra-high molecular weight polyethylene powder, the wear resistance and tensile strength of the elastomer are improved, and the maximum tensile strength is 27.9 MPa, but its abrasion is greater than 100 mm 3 / 1000 m. Chinese invention patent CN109627413B discloses a high wear-resistant polyurethane material and a preparation method thereof. By adding molybdenum disulfide nanomaterials to modify the polyurethane material, the hardness, flexibility and wear resistance have also been significantly improved, but there is a problem of incompatibility in the addition of inorganic nanomaterials. Summary of the Invention

[0004] The purpose of the present invention is to provide a wear-resistant polyurethane material and a preparation method thereof, which not only have excellent wear resistance, but also have high flame retardancy, strength, toughness and chemical corrosion resistance, and can be widely used in various high-wear working condition fields. At the same time, the preparation method is simple and feasible, easy to realize industrial production, can effectively reduce production costs, and has good economic benefits and market application prospects.

[0005] The technical solution of the present invention is realized as follows: The present invention provides a wear-resistant polyurethane material, which comprises component A and component B with a mass ratio of 100:65 - 72; Component A comprises the following raw materials in parts by weight: 102 - 120 parts of polyether polyol, 6 - 10 parts of chain extender, 0.05 - 0.1 part of catalyst, 0.3 - 0.5 part of antioxidant, 5 - 10 parts of wear-resistant enhancer, 0.04 - 0.06 part of silicone oil, and 0.3 - 0.5 part of ultraviolet absorber; Component B comprises the following raw materials in parts by weight: 35 - 45 parts of polyisocyanate, 0.02 - 0.04 part of polymerization inhibitor, and 70 - 89 parts of polyether; The wear-resistant enhancer is a microcapsule with polyurethane prepared by reacting disulfide bond-crosslinked polyurethane and modified aramid with toluene 2,4-diisocyanate as the shell material and diisocyanate reacting with water as the core material.

[0006] As a further improvement of the present invention, the polyether polyol is selected from at least one of polyether polyol N330, polytetrahydrofuran ether diol, bisphenol A diethanol ether, polytrimethylene ether glycol, tetrahydrofuran - propylene oxide copolymer diol, and polypropylene oxide diol; The chain extender is 1,4-butanediol; The catalyst is dibutyltin dilaurate or Raney nickel catalyst; The antioxidant is antioxidant 168; The ultraviolet absorber is UV-P.

[0007] As a further improvement of the present invention, the polyether comprises polytetrahydrofuran ether diol with an average molecular weight Mn = 1000 and polytetrahydrofuran ether diol with an average molecular weight Mn = 2000, with a mass ratio of 10 - 19:60 - 70, the polymerization inhibitor is phosphoric acid; The polyisocyanate is selected from at least one of toluene diisocyanate, diphenylmethane diisocyanate, aliphatic isocyanate, naphthalene 1,5-diisocyanate, benzene diisomethylene diisocyanate, and tetramethyl-m-phenylene diisocyanate.

[0008] As a further improvement of the present invention, the preparation method of the wear-resistant enhancer is as follows: S1. Chlorosulfonation modification of aramid: Immerse the aramid fiber in water, methanol, acetone, and dichloromethane in sequence, take it out, wash, dry, immerse it in a dichloromethane solution of chlorosulfonic acid, stir and react at low temperature, filter, add it to ethanol under an ice-water bath condition, soak and process, filter, wash, and dry to obtain chlorosulfonated aramid; S2. Fluorination reaction: Mix chlorosulfonated aramid and 2,2,2-trifluoroethanol and add them to a solvent, add a catalyst, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, filter to remove the catalyst, and remove the solvent under reduced pressure to obtain fluorinated / chlorosulfonated aramid; S3. Reaction with diol: Mix fluorinated / chlorosulfonated aramid and an excessive amount of diol and add them to a solvent, add a base, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, add it to water, precipitate, filter, wash the solid, and dry to obtain modified aramid; S4. Synthesis of disulfide intermediate: Cystamine dihydrochloride and acrylate are added to a solvent, stirred for reaction, precipitated with water, the solid is washed and dried to obtain the disulfide intermediate; S5. Preparation of disulfide-bonded crosslinked polyurethane: Polyether polyol and catalyst are mixed, diisocyanate is added, and the mixture is heated and stirred for reaction. Then, 1,4-butanediol is added, and the disulfide intermediate is added, followed by stirring for reaction to obtain the disulfide-bonded crosslinked polyurethane; S6. Preparation of wear-resistant enhancer: Water and emulsifier are mixed and dissolved to obtain the aqueous phase; Diisocyanate is dissolved in chlorobenzene, and the disulfide-bonded crosslinked polyurethane is added to obtain the oil phase; The aqueous phase and the oil phase are mixed, heated and stirred, modified aramid and 1,4-butanediol are added, and the mixture is stirred for reaction at a constant temperature, filtered, washed and dried to obtain the wear-resistant enhancer.

[0009] As a further improvement of the present invention, in step S1, the concentration of the dichloromethane solution of chlorosulfonic acid is 0.2-0.3 wt%, the temperature of the low-temperature stirring reaction is 8-12 °C, the time is 100-120 s, and the time of the soaking treatment is 0.5-1.5 h.

[0010] As a further improvement of the present invention, in step S2, the mass ratio of the chlorosulfonated aramid, 2,2,2-trifluoroethanol and the catalyst is 12-15:2-3:0.05-0.1, the solvent is acetonitrile, and the catalyst is aluminum trichloride.

[0011] As a further improvement of the present invention, in step S3, the mass ratio of the fluorinated / chlorosulfonated aramid, diol and base is 10:8-10:10-12, the base is selected from at least one of triethylamine, diethylamine, NaOH, KOH, the diol is selected from at least one of ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and the solvent is acetonitrile; In step S4, the mass ratio of cystamine dihydrochloride and acrylate is 4-6:7-10, the acrylate is selected from at least one of dodecyl acrylate, pentadecyl acrylate, octadecyl acrylate, docosyl acrylate, and the stirring reaction time is 10-20 min.

[0012] As a further improvement of the present invention, the mass ratio of the polyether polyol, catalyst, diisocyanate, 1,4-butanediol and disulfide intermediate in step S5 is 10-12:0.01-0.05:8-10:0.5-1:2-4. The polyether polyol is polyether polyol N330 (Mn = 3000), the catalyst is dibutyltin dilaurate, the diisocyanate is selected from at least one of toluene diisocyanate, diphenylmethane diisocyanate, aliphatic isocyanate, naphthalene 1,5-diisocyanate, benzene diisocyanate, tetramethyl-m-phenylene diisocyanate. The temperature of the heating and stirring reaction is 80-90 °C, the time is 0.5-1.5 h, and the time of the stirring reaction is 2-4 h.

[0013] As a further improvement of the present invention, the mass ratio of water and emulsifier in step S6 is 100:1-2. The emulsifier is selected from at least one of span-20, span-40, span-60, span-80, tween-20, tween-40, tween-60, tween-80, sodium dodecyl sulfate, sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate. The diisocyanate is toluene 2,4-diisocyanate and isophorone diisocyanate, and the mass ratio is 3-7:2-4. The mass ratio of the diisocyanate, disulfide bond cross-linked polyurethane, modified aramid and 1,4-butanediol is 5-11:3-5:1-2:0.5-1. The temperature of the heating and stirring is 55-65 °C, the time is 20-30 min, and the time of the heat preservation and stirring reaction is 1-2 h.

[0014] The present invention further protects a preparation method of the above-mentioned wear-resistant polyurethane material, comprising the following steps: (1) After vacuum dehydrating the polyether at 120-130 °C for 1-2 h, sampling to measure that the water content is lower than 0.05%, cooling to 65-75 °C, adding an inhibitor to the melted polyisocyanate, adding the dehydrated polyether, controlling the reaction temperature below 80 °C, and reacting for 2-4 h under stirring conditions to obtain a polyurethane prepolymer, which is component B; (2) After vacuum dehydrating the polyether polyol and chain extender at 120-130 °C for 1-2 h, sampling to measure that the water content is lower than 0.05%, cooling to 65-75 °C, adding a catalyst, antioxidant, silicone oil, ultraviolet absorber and wear-resistant enhancer, and stirring and mixing evenly to obtain component A; (3) Vacuum mixing components A and B in proportion for 20-40 s; (4) Injecting the mixture into a mold, curing and forming under the pressure conditions of 80-100 °C and 80-120 tons, and curing for 20-28 h under the condition of 75-85 °C to obtain the wear-resistant polyurethane material.

[0015] The present invention has the following beneficial effects: The wear-resistant polyurethane material prepared by the present invention overcomes the incompatibility problem of traditional inorganic additives by adding special wear-resistant enhancers and optimizing the preparation process, significantly improving the wear resistance of the material. It has good comprehensive properties, not only excellent wear resistance, but also high flame retardancy, strength, toughness and chemical corrosion resistance. It can be widely applied to various high-wear working condition fields. At the same time, the preparation method is simple and feasible, easy to realize industrial production, can effectively reduce production costs, and has good economic benefits and market application prospects.

[0016] The wear-resistant enhancer prepared by the present invention is obtained by chlorosulfonating aramid. Meta-aramid is a typical aromatic polyamide macromolecule. Due to the strong internal hydrogen bonds in its molecular structure, it has excellent properties such as high flame retardancy, thermal stability and high strength wear resistance. By grafting modification, its surface is coupled with fluorine-containing groups and alcohol hydroxyl groups. The fluorine-containing groups increase the heat resistance, wear resistance and mechanical properties of the material, and the alcohol hydroxyl groups enable it to react with diisocyanate subsequently, so that the modified aramid can be stably fixed on the polyurethane shell layer.

[0017] The present invention selects isophorone diisocyanate that can react and cure with water as the core material of the repair agent, and selects polyurethane prepared by reacting dithiol cross-linked polyurethane and modified aramid with toluene 2,4-diisocyanate as the shell material. When wear damage occurs, the shell layer will break, and the core material of the repair agent will flow out and react with the moisture in the air to achieve self-sensing and self-repair of mechanical damage inside the material. At the same time, under the stimulation of temperature and wear, the dithiol cross-linked polyurethane cracks into sulfur free radicals and then recombines to form new disulfide bonds, realizing the recombination of chemical bonds through the dynamic exchange of sulfur bonds, endowing the polyurethane with excellent self-repair performance.

[0018] The wear-resistant enhancer prepared by the present invention is embedded in the polyurethane polymer. When microcracks are generated due to the wear of the polyurethane polymer, the microcapsules break under the action of the cracks and release the repair agent. Under the capillary action, the repair agent penetrates into the cracks and undergoes a cross-linking reaction to achieve self-healing of the microcracks and restore the integrity of the polyurethane polymer. At the same time, the wear-resistant enhancer has dithiol cross-linked polyurethane with hydrophobic groups and modified aramid with fluorine-containing groups, providing excellent anti-corrosion performance. Specific Embodiments

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0020] Preparation Example 1 Preparation of Wear-Resistant Enhancer The method is as follows: S1. Chlorosulfonation modification of aramid: Soak meta-aramid fiber (DuPont) in water, methanol, acetone, and dichloromethane in sequence for 1 h each. Take it out, wash, and dry. Then soak it in a dichloromethane solution of 0.2 wt% chlorosulfonic acid, stir and react at 8 °C for 100 s, filter, add the solid to ethanol under an ice-water bath condition, soak and treat for 0.5 h, filter, wash, and dry to obtain chlorosulfonated aramid; S2. Fluorination reaction: Mix 12 g of chlorosulfonated aramid and 2 g of 2,2,2-trifluoroethanol, add them to 250 mL of acetonitrile, add 0.05 g of aluminum trichloride, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, filter to remove aluminum trichloride, remove the solvent under reduced pressure, wash, and dry to obtain fluorinated / chlorosulfonated aramid; S3. Reaction with diol: Mix 10 g of fluorinated / chlorosulfonated aramid and 8 g of 1,8-octanediol, add them to acetonitrile, add 10 g of NaOH, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, add to water, precipitate, filter, wash the solid, and dry to obtain modified aramid; S4. Synthesis of disulfide intermediate: Add 4 g of cystamine dihydrochloride and 7 g of dodecyl acrylate to a mixed solvent of 40 mL of ethanol and tetrahydrofuran (volume ratio 1:1), stir and react for 10 min, add water to precipitate for 1 h, wash the solid, and dry to obtain the disulfide intermediate; S5. Preparation of disulfide-crosslinked polyurethane: Mix 10 g of polyether polyol N330 (Mn = 3000) and 0.01 g of dibutyltin dilaurate, add 8 g of xylylene diisocyanate, heat to 80 °C, stir and react for 0.5 h, then add 0.5 g of 1,4-butanediol and 2 g of the disulfide intermediate, stir and react at 70 °C for 2 h to obtain disulfide-crosslinked polyurethane; S6. Preparation of wear-resistant enhancer: Dissolve 100 g of water and 1 g of sodium dodecyl sulfate to obtain the aqueous phase; Dissolve 3 g of toluene 2,4-diisocyanate in 150 mL of chlorobenzene, add 3 g of disulfide-crosslinked polyurethane and 2 g of isophorone diisocyanate to obtain the oil phase; Mix the aqueous phase and the oil phase, heat to 55 °C, stir for 20 min, add 1 g of modified aramid and 0.5 g of 1,4-butanediol, keep warm and stir to react for 1 h, filter by suction, wash, and dry to obtain the wear-resistant enhancer.

[0021] Preparation Example 2 Preparation of wear-resistant enhancer The method is as follows: S1. Chlorosulfonated modified aramid: Immerse meta-aramid fibers successively in water, methanol, acetone, and dichloromethane for 1 h each. Take them out, wash, and dry. Then immerse them in a dichloromethane solution of 0.3 wt% chlorosulfonic acid and stir at 12 °C for 120 s. Filter, add the solid to ethanol under an ice-water bath condition, soak for 1.5 h, filter, wash, and dry to obtain chlorosulfonated aramid; S2. Fluorination reaction: Mix 15 g of chlorosulfonated aramid and 3 g of 2,2,2-trifluoroethanol, add them to 250 mL of acetonitrile, add 0.1 g of aluminum trichloride, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, filter to remove aluminum trichloride, remove the solvent under reduced pressure, wash, and dry to obtain fluorinated / chlorosulfonated aramid; S3. Reaction with diol: Mix 10 g of fluorinated / chlorosulfonated aramid and 10 g of 1,6-hexanediol, add them to acetonitrile, add 12 g of diethylamine, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, add to water, precipitate, filter, wash the solid, and dry to obtain modified aramid; S4. Synthesis of disulfide intermediate: Add 6 g of cystamine dihydrochloride and 10 g of pentadecyl acrylate to a mixed solvent of 40 mL of ethanol and tetrahydrofuran (volume ratio 1:1), stir to react for 20 min, add water to precipitate for 1 h, wash the solid, and dry to obtain the disulfide intermediate; S5. Preparation of disulfide-crosslinked polyurethane: Mix 12 g of polyether polyol N330 (Mn = 3000) and 0.05 g of dibutyltin dilaurate, add 10 g of diphenylmethane diisocyanate, heat to 90 °C, stir to react for 1.5 h, then add 1 g of 1,4-butanediol and 4 g of the disulfide intermediate, stir at 70 °C for 4 h to obtain disulfide-crosslinked polyurethane; S6. Preparation of wear-resistant enhancer: Dissolve 100 g of water and 2 g of sodium dodecylbenzenesulfonate to obtain the aqueous phase; dissolve 7 g of toluene 2,4-diisocyanate in 150 mL of chlorobenzene, add 5 g of disulfide-crosslinked polyurethane and 4 g of isophorone diisocyanate to obtain the oil phase; mix the aqueous phase and the oil phase, heat to 65 °C, stir for 30 min, add 2 g of modified aramid and 1 g of 1,4-butanediol, keep warm and stir to react for 2 h, filter by suction, wash, and dry to obtain the wear-resistant enhancer.

[0022] Preparation Example 3 Preparation of Wear-Resistant Enhancer The method is as follows: S1. Chlorosulfonation modification of aramid: Immerse meta-aramid fibers successively in water, methanol, acetone, and dichloromethane for 1 h each. Take them out, wash, and dry. Then immerse them in a dichloromethane solution of 0.25 wt% chlorosulfonic acid and stir at 10 °C for 110 s. Filter, add the solid to ethanol under an ice-water bath condition, soak for 1 h, filter, wash, and dry to obtain chlorosulfonated aramid; S2. Fluorination reaction: Mix 13 g of chlorosulfonated aramid and 2.5 g of 2,2,2-trifluoroethanol, add them to 250 mL of acetonitrile, add 0.07 g of aluminum trichloride, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, filter to remove aluminum trichloride, remove the solvent under reduced pressure, wash, and dry to obtain fluorinated / chlorosulfonated aramid; S3. Reaction with diol: Mix 10 g of fluorinated / chlorosulfonated aramid and 9 g of 1,5-pentanediol, add them to acetonitrile, add 11 g of triethylamine, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, add to water, precipitate, filter, wash the solid, and dry to obtain modified aramid; S4. Synthesis of disulfide intermediate: Add 5 g of cystamine dihydrochloride and 8.5 g of docosyl acrylate to a mixed solvent of 40 mL of ethanol and tetrahydrofuran (volume ratio 1:1), stir to react for 15 min, add water to precipitate for 1 h, wash the solid, and dry to obtain the disulfide intermediate; S5. Preparation of disulfide-crosslinked polyurethane: Mix 11 g of polyether polyol N330 (Mn = 3000) and 0.03 g of dibutyltin dilaurate, add 9 g of toluene diisocyanate, heat to 85 °C, stir to react for 1 h, then add 0.7 g of 1,4-butanediol and 3 g of the disulfide intermediate, stir to react at 70 °C for 3 h to obtain disulfide-crosslinked polyurethane; S6. Preparation of wear-resistant enhancer: Dissolve 100 g of water and 1.5 g of sodium dodecyl sulfate to obtain the aqueous phase; dissolve 5 g of toluene 2,4-diisocyanate in 150 mL of chlorobenzene, add 4 g of disulfide-crosslinked polyurethane and 3 g of isophorone diisocyanate to obtain the oil phase; mix the aqueous phase and the oil phase, heat to 60 °C, stir for 25 min, add 1.5 g of modified aramid and 0.7 g of 1,4-butanediol, keep warm and stir to react for 1.5 h, filter by suction, wash, and dry to obtain the wear-resistant enhancer.

[0023] Comparative Preparation Example 1 Compared with Preparation Example 3, the difference is that step S2 is not carried out.

[0024] Specifically as follows: S1. Chlorosulfonation-modified aramid: Soak meta-aramid fibers successively in water, methanol, acetone, and dichloromethane for 1 h each. Take them out, wash, and dry. Then soak them in a dichloromethane solution of 0.25 wt% chlorosulfonic acid and stir at 10 °C for 110 s. Filter, add the solid to ethanol under an ice-water bath condition, soak for 1 h, filter, wash, and dry to obtain chlorosulfonated aramid; S2. Reaction with diol: Mix 10 g of fluorinated / chlorosulfonated aramid and 9 g of 1,5-pentanediol, add them to acetonitrile, add 11 g of triethylamine, heat under reflux and stir to react until no obvious HCl escapes, then stop the reaction. Add to water, precipitate, filter, wash the solid, and dry to obtain modified aramid; S3. Synthesis of disulfide intermediate: Add 5 g of cystamine dihydrochloride and 8.5 g of docosyl acrylate to a mixed solvent of 40 mL of ethanol and tetrahydrofuran (volume ratio 1:1), stir and react for 15 min, add water to precipitate for 1 h, wash the solid, and dry to obtain the disulfide intermediate; S4. Preparation of disulfide-crosslinked polyurethane: Mix 11 g of polyether polyol N330 (Mn = 3000) and 0.03 g of dibutyltin dilaurate, add 9 g of toluene diisocyanate, heat to 85 °C, stir and react for 1 h. Then add 0.7 g of 1,4-butanediol and 3 g of the disulfide intermediate, stir and react at 70 °C for 3 h to obtain disulfide-crosslinked polyurethane; S5. Preparation of wear-resistant enhancer: Mix and dissolve 100 g of water and 1.5 g of sodium dodecyl sulfate to obtain the aqueous phase; dissolve 5 g of toluene 2,4-diisocyanate in 150 mL of chlorobenzene, add 4 g of disulfide-crosslinked polyurethane and 3 g of isophorone diisocyanate to obtain the oil phase; mix the aqueous phase and the oil phase, heat to 60 °C, stir for 25 min, add 1.5 g of modified aramid and 0.7 g of 1,4-butanediol, keep warm and stir to react for 1.5 h, filter by suction, wash, and dry to obtain the wear-resistant enhancer.

[0025] Comparative Preparation Example 2 Compared with Preparation Example 3, the difference is that the disulfide intermediate is not added in step S5.

[0026] Specifically as follows: S5. Preparation of polyurethane: Mix 11 g of polyether polyol N330 (Mn = 3000) and 0.03 g of dibutyltin dilaurate, add 9 g of toluene diisocyanate, heat to 85 °C, stir and react for 1 h. Then add 0.7 g of 1,4-butanediol and 3 g of polyether polyol N330 (Mn = 3000), stir and react at 70 °C for 3 h to obtain polyurethane.

[0027] S6. Preparation of wear-resistant enhancer: 100 g of water and 1.5 g of sodium dodecyl sulfate were mixed and dissolved to obtain an aqueous phase; 5 g of toluene 2,4-diisocyanate was dissolved in 150 mL of chlorobenzene, and 4 g of polyurethane and 3 g of isophorone diisocyanate were added to obtain an oil phase; the aqueous phase and the oil phase were mixed, heated to 60 °C, stirred for 25 min, 1.5 g of modified aramid and 0.7 g of 1,4-butanediol were added, and the mixture was kept warm and stirred for reaction for 1.5 h, then filtered, washed, and dried to obtain the wear-resistant enhancer.

[0028] Comparative Preparation Example 3 Compared with Preparation Example 3, the difference lies in that no modified aramid was added in step S6.

[0029] Specifically as follows: S6. Preparation of wear-resistant enhancer: 100 g of water and 1.5 g of sodium dodecyl sulfate were mixed and dissolved to obtain an aqueous phase; 5 g of toluene 2,4-diisocyanate was dissolved in 150 mL of chlorobenzene, and 4 g of disulfide-crosslinked polyurethane and 3 g of isophorone diisocyanate were added to obtain an oil phase; the aqueous phase and the oil phase were mixed, heated to 60 °C, stirred for 25 min, 2.2 g of 1,4-butanediol was added, and the mixture was kept warm and stirred for reaction for 1.5 h, then filtered, washed, and dried to obtain the wear-resistant enhancer.

[0030] The specifications and manufacturer information of various raw materials in the examples are shown in Table 1.

[0031] Table 1 Example 1

[0032] This example provides a wear-resistant polyurethane material, including component A and component B, with a mass ratio of 100:65.

[0033] Component A includes the following raw materials in parts by weight: 102 parts of polytetrahydrofuran ether glycol (Mn = 2000), 6 parts of 1,4-butanediol, 0.05 part of dibutyltin dilaurate, 0.3 part of antioxidant 168, 5 parts of the wear-resistant enhancer prepared in Preparation Example 1, 0.04 part of silicone oil, and 0.3 part of ultraviolet absorber UV-P.

[0034] Component B includes the following raw materials in parts by weight: 35 parts of isocyanate MDI-100, 0.02 part of phosphoric acid, and 70 parts of polytetrahydrofuran ether glycol (Mn = 1000).

[0035] The preparation method includes the following steps: (1) After vacuum dehydrating polytetrahydrofuran ether glycol (Mn = 1000) at 120 °C for 1 h, the water content was measured to be less than 0.05% after sampling. The temperature was lowered to 65 °C, phosphoric acid was added to the melted isocyanate MDI-100, and the dehydrated polyether was added. The reaction temperature was controlled below 80 °C, and the reaction was carried out for 2 - 4 h under stirring conditions to obtain a polyurethane prepolymer, which is Component B; (2) After vacuum dehydrating polytetrahydrofuran ether glycol (Mn = 2000) and 1,4-butanediol at 120 °C for 1 h, the water content was measured to be less than 0.05% after sampling. The temperature was lowered to 65 °C, dibutyltin dilaurate, antioxidant 168, silicone oil, ultraviolet absorber UV-P, and wear-resistant enhancer were added, and the mixture was stirred and mixed evenly to obtain Component A; (3) Vacuum mix Components A and B in proportion for 20 s; (4) Inject the mixture into a mold, carry out curing and molding under the conditions of 80 °C and a pressure of 80 tons, and cure at 75 °C for 20 h to obtain a wear-resistant polyurethane material.

[0036] Example 2 This example provides a wear-resistant polyurethane material, including Component A and Component B, with a mass ratio of 100:72.

[0037] Component A includes the following raw materials in parts by weight: 120 parts of polyether polyol N330, 10 parts of 1,4-butanediol, 0.1 part of dibutyltin dilaurate, 0.5 part of antioxidant 168, 10 parts of the wear-resistant enhancer prepared in Preparation Example 2, 0.06 part of silicone oil, and 0.5 part of ultraviolet absorber UV-P.

[0038] Component B includes the following raw materials in parts by weight: 45 parts of isocyanate MDI-100, 0.04 part of phosphoric acid, and 89 parts of polytetrahydrofuran ether glycol (Mn = 1000).

[0039] The preparation method includes the following steps: (1) After vacuum dehydrating polytetrahydrofuran ether glycol (Mn = 1000) at 130 °C for 2 h, the water content was measured to be less than 0.05% after sampling. The temperature was lowered to 75 °C, phosphoric acid was added to the melted isocyanate MDI-100, and the dehydrated polyether was added. The reaction temperature was controlled below 80 °C, and the reaction was carried out for 4 h under stirring conditions to obtain a polyurethane prepolymer, which is Component B; (2) After vacuum dehydrating polyether polyol N330 and 1,4-butanediol at 130 °C for 2 h, the water content was measured to be less than 0.05% after sampling. The temperature was lowered to 75 °C, dibutyltin dilaurate, antioxidant 168, silicone oil, ultraviolet absorber UV-P, and wear-resistant enhancer were added, and the mixture was stirred and mixed evenly to obtain Component A; (3) Vacuum mix Components A and B in proportion for 40 s; (4) Inject the mixture into a mold, cure and mold it under the conditions of 100 °C and a pressure of 120 tons, and cure it at 85 °C for 28 h to obtain the wear-resistant polyurethane material.

[0040] Example 3 This example provides a wear-resistant polyurethane material, including component A and component B, with a mass ratio of 100:69.

[0041] Component A includes the following raw materials in parts by weight: 110 parts of polytetrahydrofuran ether glycol (Mn = 2000), 8 parts of 1,4-butanediol, 0.07 part of dibutyltin dilaurate, 0.4 part of antioxidant 168, 7 parts of the wear-resistant enhancer prepared in Preparation Example 3, 0.05 part of silicone oil, and 0.4 part of ultraviolet absorber UV-P.

[0042] Component B includes the following raw materials in parts by weight: 40 parts of isocyanate MDI-100, 0.03 part of phosphoric acid, and 82 parts of polytetrahydrofuran ether glycol (Mn = 2000).

[0043] The preparation method includes the following steps: (1) After vacuum dehydrating polytetrahydrofuran ether glycol (Mn = 2000) at 125 °C for 1.5 h, take a sample and measure that the water content is lower than 0.05%, cool down to 70 °C, add phosphoric acid to the melted isocyanate MDI-100, add the dehydrated polyether, control the reaction temperature below 80 °C, and react for 3 h under stirring conditions to obtain the polyurethane prepolymer, which is component B; (2) After vacuum dehydrating polytetrahydrofuran ether glycol (Mn = 2000) and 1,4-butanediol at 120 - 130 °C for 1.5 h, take a sample and measure that the water content is lower than 0.05%, cool down to 70 °C, add dibutyltin dilaurate, antioxidant 168, silicone oil, ultraviolet absorber UV-P and the wear-resistant enhancer, and stir and mix evenly to obtain component A; (3) Vacuum mix component A and component B in proportion for 30 s; (4) Inject the mixture into a mold, cure and mold it under the conditions of 90 °C and a pressure of 100 tons, and cure it at 80 °C for 24 h to obtain the wear-resistant polyurethane material.

[0044] Comparative Example 1 Compared with Example 3, the difference is that the wear-resistant enhancer is prepared from Comparative Preparation Example 1.

[0045] Comparative Example 2 Compared with Example 3, the difference is that the wear-resistant enhancer is prepared from Comparative Preparation Example 2.

[0046] Comparative Example 3 Compared with Example 3, the difference lies in that the wear-resistant enhancer is prepared from Comparative Preparation Example 3.

[0047] Comparative Example 4 Compared with Example 3, the difference lies in that no wear-resistant enhancer is added.

[0048] Test Example 1 The wear-resistant polyurethane materials prepared in Examples 1-3 and Comparative Examples 1-4 were tested for properties such as wear resistance, strength, and toughness, and the test results were recorded, as shown in Table 2.

[0049] Table 2

[0050] As can be seen from the above table, the wear-resistant polyurethane materials prepared in Examples 1-3 of the present invention have good wear resistance, strength, and toughness.

[0051] Test Example 2 The wear-resistant polyurethane materials prepared in Examples 1-3 and Comparative Examples 1-4 were tested for self-healing performance, and the results are shown in Table 3.

[0052] The tensile properties of the material before and after self-healing were tested using a universal testing machine at a tensile rate of 50 mm / min. The material was cut into rectangular specimens with dimensions of 35.0 mm × 2.0 mm × 0.5 mm, and the self-healing performance of the material was evaluated by comparing the ultimate tensile strength of the specimens before and after self-healing. There were 3 specimens in each group, and the results were averaged.

[0053] In the self-healing test, the specimen was first cut in the middle with a knife, then spliced, and the spliced specimen was induced to self-heal at 60 °C and a humidity of 90 RH%, and a tensile test was performed on the self-healed specimen.

[0054] Self-healing efficiency H E is: H E = σ a / σ b × 100% In the formula: σ b , σ a are the ultimate tensile strengths of the specimens before and after self-healing, respectively.

[0055] Table 3

[0056] As can be seen from the above table, the wear-resistant polyurethane materials prepared in Examples 1-3 of the present invention have good self-healing performance.

[0057] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A wear-resistant polyurethane material, characterized in that, It includes Component A and Component B with a mass ratio of 100:65 - 72; Component A includes the following raw materials in parts by weight: 102 - 120 parts of polyether polyol, 6 - 10 parts of chain extender, 0.05 - 0.1 part of catalyst, 0.3 - 0.5 part of antioxidant, 5 - 10 parts of wear-resistant enhancer, 0.04 - 0.06 part of silicone oil, 0.3 - 0.5 part of ultraviolet absorber; Component B includes the following raw materials in parts by weight: 35 - 45 parts of polyisocyanate, 0.02 - 0.04 part of polymerization inhibitor, 70 - 89 parts of polyether; The wear-resistant enhancer is a microcapsule with polyurethane prepared by reacting disulfide bond-crosslinked polyurethane and modified aramid with toluene 2,4-diisocyanate as the shell material and diisocyanate reacting with water as the core material.

2. The wear-resistant polyurethane material according to claim 1, wherein The polyether polyol is selected from at least one of polyether polyol N330, polytetrahydrofuran ether diol, bisphenol A bis(2-hydroxyethyl) ether, polytrimethylene ether glycol, tetrahydrofuran-oxypropylene copolymer diol, polyoxypropylene diol; The chain extender is 1,4-butanediol; The catalyst is dibutyltin dilaurate or Raney nickel catalyst; The antioxidant is antioxidant 168; The ultraviolet absorber is UV-P.

3. The wear-resistant polyurethane material according to claim 1, characterized in that, The polyether includes polytetrahydrofuran ether diol with an average molecular weight Mn = 1000 and polytetrahydrofuran ether diol with an average molecular weight Mn = 2000, with a mass ratio of 10 - 19:60 - 70, the polymerization inhibitor is phosphoric acid; The polyisocyanate is selected from at least one of toluene diisocyanate, diphenylmethane diisocyanate, aliphatic isocyanate, naphthalene 1,5-diisocyanate, benzylidene diisocyanate, tetramethyl-m-xylylene diisocyanate.

4. The wear-resistant polyurethane material according to claim 1, characterized in that, The preparation method of the wear-resistant enhancer is as follows: S1. Chlorosulfonation modification of aramid: Immerse aramid fiber in water, methanol, acetone, dichloromethane in sequence, take out, wash, dry, immerse in dichloromethane solution of chlorosulfonic acid, stir and react at low temperature, filter, add to ethanol under ice-water bath condition, soak and treat, filter, wash, dry to obtain chlorosulfonated aramid; S2. Fluorination reaction: Mix chlorosulfonated aramid and 2,2,2-trifluoroethanol and add to a solvent, add a catalyst, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, filter to remove the catalyst, remove the solvent under reduced pressure to obtain fluorinated / chlorosulfonated aramid; S3. Reaction with diol: Mix fluorinated / chlorosulfonated aramid and excessive diol and add to a solvent, add a base, heat under reflux and stir to react until no obvious HCl escapes, stop the reaction, add to water, precipitate, filter, wash the solid, dry to obtain modified aramid; S4. Synthesis of disulfide intermediate: Add cystamine dihydrochloride and acrylate to a solvent, stir to react, add water to precipitate, wash the solid, dry to obtain the disulfide intermediate; S5. Preparation of disulfide bond-crosslinked polyurethane: Mix polyether polyol and catalyst, add diisocyanate, heat and stir to react, then add 1,4-butanediol, add the disulfide intermediate, stir to react to obtain disulfide bond-crosslinked polyurethane; S6. Preparation of wear-resistant enhancer: Mix and dissolve water and an emulsifier to obtain an aqueous phase; dissolve a diisocyanate in chlorobenzene, add disulfide-crosslinked polyurethane to obtain an oil phase; mix the aqueous phase and the oil phase, heat and stir, add modified aramid and 1,4-butanediol, keep warm and stir for reaction, filter, wash, and dry to obtain the wear-resistant enhancer.

5. The wear-resistant polyurethane material according to claim 4, wherein In step S1, the concentration of the dichloromethane solution of chlorosulfonic acid is 0.2 - 0.3 wt%, the temperature of the low-temperature stirring reaction is 8 - 12 °C, the time is 100 - 120 s, and the time of the soaking treatment is 0.5 - 1.5 h.

6. The wear-resistant polyurethane material according to claim 4, characterized in that, In step S2, the mass ratio of the chlorosulfonated aramid, 2,2,2-trifluoroethanol, and the catalyst is 12 - 15:2 - 3:0.05 - 0.1, the solvent is acetonitrile, and the catalyst is aluminum trichloride.

7. The wear-resistant polyurethane material according to claim 4, wherein In step S3, the mass ratio of the fluorinated / chlorosulfonated aramid, diol, and base is 10:8 - 10:10 - 12, the base is selected from at least one of triethylamine, diethylamine, NaOH, and KOH, the diol is selected from at least one of ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol, and the solvent is acetonitrile; in step S4, the mass ratio of cystamine dihydrochloride and acrylate is 4 - 6:7 - 10, the acrylate is selected from at least one of dodecyl acrylate, pentadecyl acrylate, octadecyl acrylate, and docosyl acrylate, and the time of the stirring reaction is 10 - 20 min.

8. The wear-resistant polyurethane material according to claim 4, characterized in that, In step S5, the mass ratio of the polyether polyol, catalyst, diisocyanate, 1,4-butanediol, and disulfide intermediate is 10 - 12:0.01 - 0.05:8 - 10:0.5 - 1:2 - 4, the polyether polyol is polyether polyol N330 (Mn = 3000), the catalyst is dibutyltin dilaurate, the diisocyanate is selected from at least one of toluene diisocyanate, diphenylmethane diisocyanate, aliphatic isocyanate, naphthalene 1,5-diisocyanate, benzylidene diisocyanate, and tetramethyl-m-xylylene diisocyanate, the temperature of the heating and stirring reaction is 80 - 90 °C, the time is 0.5 - 1.5 h, and the time of the stirring reaction is 2 - 4 h.

9. The wear-resistant polyurethane material according to claim 4, characterized in that, In step S6, the mass ratio of water and the emulsifier is 100:1 - 2, the emulsifier is selected from at least one of Span-20, Span-40, Span-60, Span-80, Tween-20, Tween-40, Tween-60, Tween-80, sodium dodecyl sulfate, sodium dodecyl sulfonate, and sodium dodecylbenzenesulfonate, the diisocyanate is toluene 2,4-diisocyanate and isophorone diisocyanate, with a mass ratio of 3 - 7:2 - 4, the mass ratio of the diisocyanate, disulfide-crosslinked polyurethane, modified aramid, and 1,4-butanediol is 5 - 11:3 - 5:1 - 2:0.5 - 1, the temperature of the heating and stirring is 55 - 65 °C, the time is 20 - 30 min, and the time of the heat-preserving and stirring reaction is 1 - 2 h.

10. A method for preparing a wear-resistant polyurethane material according to any one of claims 1-9, characterized in that, It includes the following steps: (1) After vacuum dehydrating polyether at 120 - 130 °C for 1 - 2 h, sampling to measure that the water content is lower than 0.05%, cooling down to 65 - 75 °C, adding an inhibitor to the melted polyisocyanate, adding the dehydrated polyether, controlling the reaction temperature below 80 °C, and reacting for 2 - 4 h under stirring conditions to obtain a polyurethane prepolymer, which is Component B; (2) After vacuum dehydrating polyether polyol and chain extender at 120 - 130 °C for 1 - 2 h, sampling to measure that the water content is lower than 0.05%, cooling down to 65 - 75 °C, adding a catalyst, antioxidant, silicone oil, ultraviolet absorber and wear-resistant enhancer, and stirring and mixing evenly to obtain Component A; (3) Vacuum mixing Component A and Component B in proportion for 20 - 40 s; (4) Injecting the mixture into a mold, curing and forming under the pressure conditions of 80 - 100 °C and 80 - 120 tons, and aging for 20 - 28 h under the condition of 75 - 85 °C to obtain a wear-resistant polyurethane material.

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