A highly wear-resistant polyurethane material and preparation method thereof

Abstract

The present application provides a highly wear-resistant polyurethane material and a preparation method thereof. The polyurethane material comprises the following raw materials in parts by weight: 100 parts of isocyanate, 60-80 parts of polyester polyol, 8-12 parts of chain extender, 6-10 parts of cross-linking agent, 5-9 parts of bridging agent, and 0.5-1.5 parts of filler; wherein the cross-linking agent comprises a trihydroxy aromatic compound, and the bridging agent comprises a polyether polyamide block polymer. By introducing a trihydroxy aromatic compound having trifunctionality and a rigid structure into the polyurethane system, and synergistically coordinating with a polyether polyamide block polymer having polar segments and flexible segments, a molecular system having both a rigid reinforced network and a flexible connection structure is constructed. While improving the structural stability and wear resistance of the hard segment, the material effectively alleviates the problem of insufficient flexibility caused by high cross-linking density or rigid segments in traditional highly wear-resistant polyurethanes, enabling the polyurethane material to achieve both wear resistance and flexibility.

Description

Technical Field

[0001] The present application belongs to the technical field of polymer materials, and specifically relates to a highly wear-resistant polyurethane material and a preparation method thereof. Background Art

[0002] Polyurethane materials are widely used in wear-resistant components such as shoe soles, seals, conveyor belts, and industrial rollers due to their excellent mechanical properties, wear resistance, elasticity, and processability. In particular, thermoset polyurethanes, formed by the reaction of diisocyanates, polyols, and chain extenders, can achieve customized performance by adjusting the ratio of soft segments to hard segments. However, achieving both high wear resistance and good flexibility places higher demands on the microstructure of the polyurethane material.

[0003] In order to improve the wear resistance of polyurethane, the existing technology mainly adopts methods such as increasing the proportion of hard segments, increasing the cross-linking density or introducing inorganic fillers to strengthen the surface rigidity of the material. This type of method improves the cutting resistance and friction resistance to a certain extent, but it also brings about the problem of overall rigidification of the material, resulting in a decrease in its flexibility and ductility, limiting its adaptability in high deformation scenarios. On the other hand, in order to improve flexibility, plasticization modification or increasing the proportion of soft segments are often used, but these methods often sacrifice wear resistance, making it difficult to achieve an effective balance between the two.

[0004] For example, patent CN116694216A discloses a room temperature curing two-component high-strength, high-elasticity, and high-wear-resistant polyurethane resin. By introducing a combination of lightweight fillers and nanofillers, and combining polyols, isocyanates, and small molecule chain extenders to construct a main chain structure, it achieves good tensile strength and wear resistance. This solution is based on the in-situ modification polymerization strategy of the prepolymer, and designs film-forming and curing reaction paths in the A / B components respectively, which is suitable for the wear protection needs in coating applications. However, the dominant characteristics of the hard segment in this type of formula system are still relatively obvious. In scenarios requiring higher flexibility and deformation adaptability, there is still room for further optimization of its structural design.

[0005] Therefore, there is still room for improvement in the comprehensive performance of existing polyurethane materials, and in particular, there is a need to provide a polyurethane material that can simultaneously maintain high wear resistance and good flexibility. Summary of the Invention

[0006] In view of this, the present application provides a highly wear-resistant polyurethane material and a preparation method thereof, aiming to solve the problem that the improvement of wear resistance in existing polyurethane materials is often accompanied by a decrease in flexibility, and to provide a polyurethane material that structurally achieves both high wear resistance and good flexibility. By collaboratively designing chain extenders, cross-linking agents, bridging agents and filler systems, the overall structural stability and interface synergy of the material are effectively improved, and good flexibility is taken into account while having high wear resistance.

[0007] In a first aspect, the present application provides a highly wear-resistant polyurethane material, comprising the following raw materials in parts by mass: 100 parts of isocyanate, 60 to 80 parts of polyester polyol, 8 to 12 parts of chain extender, 6 to 10 parts of cross-linking agent, 5 to 9 parts of bridging agent, and 0.5 to 1.5 parts of filler; wherein the cross-linking agent comprises a trihydroxy aromatic compound, and the bridging agent comprises a polyether polyamide block polymer.

[0008] According to the present application, by introducing a trihydroxy aromatic compound with trifunctionality and a rigid structure into the polyurethane system, and synergistically coordinating it with a polyether polyamide block polymer having polar segments and flexible segments, a molecular system with both a rigid reinforced network and a flexible connection structure is constructed. While improving the stability and wear resistance of the hard segment structure, it effectively alleviates the problem of insufficient flexibility caused by high cross-linking density or rigid segmentation in traditional high-wear-resistant polyurethanes, so that the polyurethane material can take into account both wear resistance and flexibility.

[0009] Specifically, the isocyanate serves as a reactive component of the polyurethane backbone, providing -NCO functional groups to react with polyol components to form a basic polyurethane skeleton structure and regulate the degree of crosslinking and mechanical strength of the material; the polyester polyol serves as a source of flexible chain segments, and after introduction, provides chain segment slippage and deformation space in the polyurethane system, which helps to improve the overall flexibility and ductility of the material; the chain extender participates in the construction of the backbone as a chain growth monomer, enhances the integrity and continuity of the polyurethane hard segment structure, and provides the required basic strength support for the material; the crosslinking agent is a trihydroxy aromatic compound, which can react with isocyanate at multiple points to form multi-dimensional chemical crosslinking points. Its rigid aromatic ring can induce the polyurethane hard segment to form a stable microcrystalline phase, thereby improving the structural stability and wear resistance of the material; the bridging agent is a polyether polyamide block polymer, which contains both flexible polyether segments and polar polyamide segments in the molecule, and can form an interface connection area between the soft segment and the hard segment, providing a stress transfer effect. It can guide the segment distribution and stress dispersion during external mechanical stress, thereby improving the flexible response capability of the system.

[0010] It should be noted that the cross-linking agent constructs a stable hard segment connection structure, forming the strength framework of the polyurethane material; the bridging agent regulates the interface transition between the soft segment and the hard segment, buffers the local rigidity concentration caused by the cross-linking density, and stabilizes the microphase distribution. The two work together to construct a composite network structure in which a rigid reinforcement structure and a flexible transition segment coexist, so that the polyurethane material provided by the present invention can effectively improve flexibility while maintaining high wear resistance. The filler is dispersed in the matrix in a low addition amount, improves the surface wear resistance of the material, and works together with the cross-linking structure and the bridging structure to enhance the interface stability and overall structural consistency of the polyurethane.

[0011] Through the coordinated design and construction of the above-mentioned components, the polyurethane material provided in this application forms a multi-scale structural network that is collaboratively supported by rigid reinforcement structures, flexible connecting segments and dispersed reinforcing fillers, which significantly improves the overall flexibility while improving wear resistance. It is suitable for application scenarios that require both surface wear and deformation adaptability.

[0012] In some embodiments, the trihydroxy aromatic compound includes trimesoylethanolamine and mesityl alcohol, and the mass ratio of trimesoylethanolamine to mesityl alcohol is 1:1.5-2.5.

[0013] In some of the above embodiments, by compounding trimesoylethanolamine and mesityl alcohol as crosslinking agents, a crosslinked network structure with a flexible-rigid synergistic configuration is introduced into the polyurethane hard segment microdomain, thereby further improving the wear resistance and flexibility of the polyurethane material.

[0014] Specifically, both trimesoylethanolamine and mesitylbenzyl alcohol have symmetrical aromatic structures with regular molecular configurations and uniform functional group distribution. They can more effectively serve as induced crystallization centers in the microphase structure, prompting the polyurethane hard segments to form ordered microcrystalline regions. During the crosslinking reaction, they can form a well-directed, structurally symmetrical multi-point crosslinked network, which helps improve the density and size retention of the microdomain structure. Among them, trimesoylethanolamine, due to the introduction of amide-type side chains into its molecular structure, can still retain certain polar structural units after the crosslinking points are formed, and has strong interfacial compliance. Meanwhile, mesitylbenzyl alcohol has a higher structural rigidity and stronger induced stacking properties, which is more conducive to the regular arrangement of microdomain crosslinking points. This composite crosslinking design combines the regularity of the aromatic core with the complementary functional characteristics to construct a crosslinked network structure that is both stable and flexible. This allows the polyurethane system to enhance the stability and wear resistance of the hard segments while retaining the necessary space for chain segment movement, further improving the material's flexibility.

[0015] It should be noted that the amide structure introduced by trimesoylethanolamine can also form hydrogen bonds or polar synergistic effects with the polyamide segments in the polyether polyamide block polymer, constructing a microscopic synergistic anchoring network between the cross-linking point area and the bridging structure, enhancing the stability of the bridging chain segment at the interface, preventing the structure from being disembedded or broken under load, and improving the stress response consistency and energy consumption capacity of the material.

[0016] In some embodiments, the polyether polyamide block polymer is obtained by co-condensation of hydroxyl-terminated polyethylene glycol and ω-aminododecanoic acid, wherein the molar ratio of the hydroxyl-terminated polyethylene glycol to ω-aminododecanoic acid is 1:2-2.5.

[0017] In some of the aforementioned embodiments, a hydroxyl-terminated polyethylene glycol (PEG) serves as a position-limiting flexible segment, which is then subjected to a polycondensation reaction with ω-aminododecanoic acid, which possesses both amino and carboxyl functional groups. This results in a block structure comprising both a flexible polyether segment and a polar polyamide segment within the resulting bridging agent molecule. The hydroxyl-terminated PEG, which can be either double-terminated or single-terminated, provides reactive sites or chain length control during the polycondensation reaction, helping to limit polymer molecular weight and adjust the structural ratio and distribution of the flexible segments.

[0018] After the obtained polyether polyamide block polymer is introduced into the polyurethane system as a bridging agent, its polyamide segment can enhance the interfacial affinity with the polar region or cross-linking point in the structure, forming a physical entanglement or hydrogen bond network, and improving the stability of the hard segment connection area; the polyether segment can also play a regulatory role in interchain connection, compatibility transition and stress dispersion in the structure, thereby giving the system better chain segment slip ability and structural flexibility.

[0019] By controlling the molar ratio of hydroxyl-terminated polyethylene glycol to ω-aminododecanoic acid within a range of 1:2 to 2.5, the resulting bridging agent maintains an appropriate molecular weight and block ratio within its structure. This ensures sufficient polar block anchoring capacity while preventing processing difficulties and reduced compatibility associated with overly long molecular segments. Ultimately, the bridging agent achieves its dual functions of structural flexibility regulation and interfacial stabilization, resulting in improved stress transfer and further enhanced polyurethane material flexibility without sacrificing wear resistance.

[0020] In some embodiments, the hydroxyl-terminated polyethylene glycol is a double-terminated hydroxyl-capped polyethylene glycol, and the weight average molecular weight of the hydroxyl-terminated polyethylene glycol is 500-700.

[0021] In some of the above embodiments, the double-end hydroxyl-terminated structure not only provides a limiting effect in the condensation reaction with ω-aminododecanoic acid, but also retains the hydroxyl group at one end as a reaction site, which is then reacted with isocyanate to connect to the main chain in the subsequent polyurethane synthesis to form a covalent bridging structure. This structural design enables the bridging agent to have the synergistic function of flexible segments and polar segments while also having the ability to embed into the main chain, significantly enhancing its stability and anchoring force in the interface area. Through this covalent insertion mechanism, the bridging agent not only plays the role of stress transition and flexibility regulation between segments in the polyurethane system, but also forms a continuous structural connection with the main chain, avoiding the phenomena of segment slippage, uneven dispersion or interface de-embedding that may occur under physical doping conditions, thereby further improving the coordination of the system's force response.

[0022] Compared with bridging agents that do not have main chain reaction activity, structural bridging agents constructed using double-ended hydroxyl polyethylene glycol have stronger anchoring effect and structural integration. Especially under stress, they can stably maintain the functional role of the bridging structure in the system, thereby further improving the flexibility of the polyurethane material while maintaining wear resistance.

[0023] At the same time, the molecular weight of the hydroxy-terminated polyethylene glycol is controlled in the range of 500~700. The dihydroxy-terminated polyethylene glycol within this molecular weight range has good melt fluidity and reactivity, and can efficiently construct a polyether-polyamide structure and form a bridging agent with a suitable chain length, so that it can better play the triple functions of structural connection, flexibility adjustment and polar anchoring in the polyurethane system, thereby enabling the polyurethane material to better balance wear resistance and flexibility.

[0024] In some embodiments, the filler includes an imidazole-modified filler, wherein the imidazole-modified filler is obtained by modifying an inorganic filler with an imidazole-based silane coupling agent.

[0025] In some of the aforementioned embodiments, by surface-modifying the inorganic filler with a silane coupling agent containing imidazole groups, polar imidazole functional groups can be introduced onto the filler surface, resulting in improved dispersibility and interfacial bonding within the polyurethane system. Imidazole groups contain heterocyclic structures within their molecules, exhibiting high polarity, high electron density, and multi-point coordination. These groups can form hydrogen bonds, π-π stacking, or electrostatic interactions with structures such as amides, ureas, and aromatic rings within the polyurethane system, building a stable interfacial bonding network.

[0026] Compared with common amino, carboxyl or alkoxy functional groups, the imidazole structure has stronger polar interaction ability and intermolecular compatibility, which can achieve tighter polar entanglement and structural synergy in the polyurethane hard segment microregion, thereby improving the anchoring stability of the filler in the interface area; at the same time, its excellent interfacial affinity can also reduce the risk of filler agglomeration and improve its dispersion uniformity in the matrix.

[0027] It is understood that imidazole-modified fillers and polar crosslinkers (trimellitic ethanolamine) or bridging agents (polyamide segments) can form multi-point polar synergy, building a stable synergistic anchoring network at the filler-polymer interface, which helps alleviate stress concentration and localized interfacial discontinuities. Compared to unmodified fillers or fillers modified with conventional grafting groups, imidazole-based fillers are more conducive to improving interfacial energy dissipation and structural continuity, enhancing material wear resistance while further improving flexibility.

[0028] In some embodiments, the inorganic filler includes a flake filler and a spherical filler, and the mass ratio of the flake filler to the spherical filler is 2 to 3:1.

[0029] In some of the aforementioned embodiments, by combining flaky fillers with spherical fillers of varying morphologies and reinforcement mechanisms, a multi-scale synergistic reinforcement structure can be constructed within the polyurethane material. The flaky fillers, which have a large specific surface area and two-dimensional structural characteristics, can be arranged in a planar direction within the matrix after dispersion, forming a slip-guiding layer and crack deflection channel, effectively extending the crack propagation path and improving surface shear resistance and overall wear resistance. The spherical fillers, with their uniform particle size and excellent rigidity, can provide structural support, gap filling, and dispersion stability within the system, avoiding the agglomeration effect caused by stacking the flaky fillers and mitigating the damage to the material's flexibility caused by sudden microscopic rigidity changes.

[0030] At the same time, the mass ratio of the two is controlled within the range of 2~3:1, so that the flake filler occupies a dominant reinforcing position in the system, thereby giving full play to its ability to construct a slip layer and anti-crack structure; at the same time, an appropriate amount of spherical filler is added to construct structural transition and dispersion auxiliary functions through point support, while maintaining the reinforcing effect, the structural uniformity and flexible foundation are improved, thereby effectively maintaining the flexibility of the polyurethane material while improving the wear resistance of the material.

[0031] In some embodiments, the flaky filler has an average flake diameter of 1 to 10 μm and an average thickness of 10 to 100 nm; the spherical filler has an average particle size of 5 to 20 μm. For example, in one embodiment of the present application, montmorillonite flakes with an average flake diameter of 5 μm and an average thickness of 60 nm are used as the flaky filler, and silica particles with an average particle size of 10 μm are used as the spherical filler.

[0032] In some embodiments, the chain extender comprises a dihydroxy aromatic compound, and the dihydroxy aromatic compound comprises hydroquinone dihydroxyethyl ether.

[0033] In some of the above-mentioned embodiments, the hydroquinone dihydroxyethyl ether molecule contains a symmetrical aromatic ring structure and hydroxyl functional groups at both ends, and can participate in the construction of the hard segment as a chain growth monomer in the polyurethane polymerization reaction. The central aromatic ring provides good regularity and rigid support, and the ethylene glycol segments at both ends have a certain flexibility and adjustable spacing, which helps to construct a hard segment structure with consistent direction and moderate segment length, thereby improving the microphase regularity of the polyurethane system and the continuity of the segment connection.

[0034] In this embodiment, the chain extender is used. On the one hand, it can work with aromatic isocyanate and aromatic cross-linker to construct a hard segment skeleton with consistent structural style, thereby improving the dimensional stability and shear resistance of the material. On the other hand, the flexible ethylene glycol segments at both ends introduce local deformable buffer segments in the hard segment connection area, which can establish a soft connection transition between the rigid structure and the flexible structure, alleviate the stress concentration caused by the sudden change in rigidity, and improve the stress transfer efficiency between structural regions.

[0035] Furthermore, this flexible chain segment enhances compatibility with flexible structures like bridging agents, creating a smooth transition between the crosslinked and bridging networks and improving the interfacial harmony of the entire system. Compared to chain extenders with overly soft or rigid structures, the chain segments constructed with hydroquinone dihydroxyethyl ether enhance the wear resistance of polyurethane materials while maintaining their flexibility.

[0036] In some embodiments, the isocyanate includes at least one of toluene diisocyanate and diphenylmethane diisocyanate. Based on the above embodiments, phenylene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI), as aromatic isocyanates, possess good reactivity and structural rigidity. Together with aromatic chain extenders and crosslinkers, they can construct a hard segment framework with strong regularity and high thermal stability, forming the fundamental components for achieving polyurethane wear resistance.

[0037] In some embodiments, the polyester polyol includes polycaprolactone diol, and the weight-average molecular weight of the polycaprolactone diol is 800-2000. Based on the above embodiments, polycaprolactone diol is a preferred source of soft segments in the polyester polyol, exhibiting high segment flexibility and good polar compatibility. Controlling the molecular weight within the range of 800-2000 ensures sufficient segment flexibility while maintaining system reaction efficiency and mechanical balance, thereby helping to maintain the flexibility of the polyurethane material.

[0038] In some embodiments, the raw materials further include 0.1 to 0.5 parts of an organotin catalyst. Based on the above embodiments, the introduction of an organotin catalyst, such as stannous octoate or dibutyltin dilaurate, can significantly increase the reaction rate between the isocyanate and the hydroxyl component, ensuring that the multifunctional components in the system, such as the bridging agent, chain extender, and crosslinking agent, can fully react, thereby avoiding network discontinuity or local performance degradation due to incomplete reaction.

[0039] In a second aspect, the present application provides a method for preparing a highly wear-resistant polyurethane material, comprising the following steps:

[0040] Providing a raw material for the polyurethane material according to any embodiment of the first aspect;

[0041] The raw materials are mixed and then cured to obtain a polyurethane material.

[0042] According to the present application, the method is based on a raw material system with a clear functional structure. The polymerization process does not require complex reaction control conditions. Conventional mixing and curing steps can form a polyurethane material structural network with high crosslinking stability and interfacial synergy. The various raw material components have good reaction matching and polarity compatibility in their molecular structures. During the reaction process, they can synergistically integrate into the system to construct a rigid hard segment network, a flexible segment buffer zone, and a multi-point interfacial anchoring structure.

[0043] This method has the advantages of simple operation, strong adaptability, and high system uniformity. The polyurethane material produced exhibits excellent wear resistance and flexibility, and is suitable for a variety of application scenarios that have dual requirements for material wear resistance and deformation adaptability.

[0044] In some embodiments, the method specifically includes: adding polyester polyol, bridging agent, chain extender, crosslinking agent, filler and other components into a mixing container according to a predetermined ratio, and premixing at 60-90° C. for 30-60 minutes under stirring conditions to fully disperse and evenly mix the various raw materials; preferably, the bridging agent and crosslinking agent can be premixed with the polyester polyol to form a well-distributed state in the system;

[0045] Under nitrogen protection, heat the isocyanate component to 60-70°C until it is molten, then slowly add it to the mixed system and continue stirring and reacting for 20-30 minutes to form a uniform prepolymer mixture;

[0046] After the reaction mixture is poured into the mold, it is placed in an environment of 80-120°C for curing for 3-5 hours to complete the reaction molding. After cooling and demoulding, the polyurethane material is obtained.

[0047] In a third aspect, the present application provides a wear-resistant product, which includes the polyurethane material according to any embodiment of the first aspect, or the polyurethane material prepared by the method described in the second aspect.

[0048] According to the present application, the polyurethane material constructs a composite network structure with coexistence of rigidity and flexibility, stable interface and uniform stress dispersion at the molecular scale through cross-linking structure reinforcement, bridging structure adjustment and filler structure coordination. It has excellent wear resistance and flexibility and is suitable for preparing a variety of wear-resistant products that withstand repeated friction, shear, extrusion or deformation.

[0049] The wear-resistant polyurethane material described in this application can be processed and molded into structural components such as seals, conveyor belt coverings, shoe soles, shock-absorbing pads, roller rubber coatings, coating films, or elastic wear-resistant linings. During use, it can maintain excellent wear-resistant stability and reduce material wear rate, while also maintaining flexible response and structural integrity under deformation conditions. Compared to conventional highly cross-linked polyurethane materials that are prone to peeling and cracking due to increased brittleness, the polyurethane material in this application significantly improves the actual application life and processing adaptability of wear-resistant products through the coordinated design of flexible segments and structures.

[0050] Compared with the prior art, the present invention has the following advantages:

[0051] By collaboratively designing the cross-linking agent, bridging agent, chain extender and filler structure, a composite network system with rigid reinforcement structure, flexible connecting chain segments and multi-scale interface coordination is constructed in the polyurethane material. Without relying on complex processes, the wear resistance and flexibility of the polyurethane material are synergistically improved, which is more suitable for application scenarios that require both surface wear and deformation adaptability. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0053] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with an embodiment or example is included in at least one embodiment or example of the present application. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0055] In this application, unless otherwise specified, "parts" refer to "parts by mass".

[0056] The scheme of the present application is described below with reference to the following specific examples. Unless otherwise specified, the raw materials used in the following examples are all from common commercial products, and the devices or equipment used are all purchased from conventional market sales channels.

[0057] Flaky montmorillonite: average flake diameter is 5 μm, average thickness is 60 nm;

[0058] Silica particles: average particle size is 10 μm.

[0059] Preparation Example 1-1

[0060] Preparation of polyether polyamide block polymers:

[0061] Double-end hydroxyl-terminated polyethylene glycol with a weight-average molecular weight of 600 and ω-aminododecanoic acid were directly placed in a reactor with a molar ratio of 1:2.2. 1% of dibutyltin dilaurate and 0.5% of dibutylhydroxytoluene, accounting for 1% by mass of the reactants, were added. The mixture was stirred at 150° C. for 5 h to obtain a polyether polyamide block polymer A.

[0062] Preparation Example 1-2

[0063] Preparation of polyether polyamide block polymers:

[0064] A single-end hydroxyl-terminated polyethylene glycol with a weight-average molecular weight of 600 and ω-aminododecanoic acid were directly placed in a reactor with a molar ratio of 1:2.2. 1% by mass of dibutyltin dilaurate and 0.5% by mass of dibutylhydroxytoluene were added. The mixture was stirred at 150° C. for 5 h to obtain a polyether polyamide block polymer B.

[0065] Preparation Example 2-1

[0066] Preparation of filler:

[0067] 10 parts of inorganic filler (flaky montmorillonite and silica particles in a mass ratio of 2.5:1) were dispersed in 200 parts of a mixed solution of ethanol and water in a volume ratio of 70 / 30. After ultrasonic dispersion for 20 minutes, 1 part of N-(trimethoxysilylpropyl)imidazole was added. The mixture was heated under reflux at 70°C for 3 hours. After the reaction, the mixture was centrifuged, washed with water three times, and vacuum dried at 50°C to obtain an imidazole-modified filler as filler A.

[0068] Preparation Example 2-2

[0069] Preparation of filler:

[0070] Similar to Preparation Example 2-1, the only difference is that the inorganic filler is flaky montmorillonite, and an imidazole-modified filler is obtained as filler B.

[0071] Preparation Example 2-3

[0072] Preparation of filler:

[0073] Similar to Preparation Example 2-1, the only difference is that the inorganic filler is silica particles, and an imidazole-modified filler is obtained as filler C.

[0074] Preparation Example 2-4

[0075] Preparation of filler:

[0076] Similar to Preparation Example 2-1, the only difference is that γ-aminopropyltriethoxysilane is used instead of N-(trimethoxysilylpropyl)imidazole to obtain an amino-modified filler as filler D.

[0077] Example 1

[0078] Preparation of highly wear-resistant polyurethane materials:

[0079] 70 parts of polycaprolactone diol with a weight-average molecular weight of 1200 and 10 parts of hydroquinone dihydroxyethyl ether are mixed evenly and stirred to dissolve at 50°C; then 8 parts of a crosslinker (trimethylene glycol amine and tribenzyl alcohol in a mass ratio of 1:2) and 7 parts of a polyether polyamide block polymer A are added and continued to be stirred and dispersed; the temperature is then raised to 70°C, 1 part of a filler A is added, and ultrasonic dispersion is performed evenly; then 100 parts of diphenylmethane diisocyanate are heated and melted at 65°C and slowly added to the above mixture, and the mixture is reacted at 70°C for 30 minutes to obtain a polyurethane prepolymer; then 0.3 parts of dibutyltin dilaurate are added to the polyurethane prepolymer, which is then transferred to a mold, heated and cured at 100°C for 4 hours, cooled and demolded after curing to obtain a polyurethane material.

[0080] Example 2

[0081] Preparation of highly wear-resistant polyurethane materials:

[0082] The process is substantially the same as Example 1, except that only 8 parts of trimesoylethanolamine are used as the cross-linking agent.

[0083] Example 3

[0084] Preparation of highly wear-resistant polyurethane materials:

[0085] The process is substantially the same as Example 1, except that only 8 parts of mesityl alcohol are used as the cross-linking agent.

[0086] Example 4

[0087] Preparation of highly wear-resistant polyurethane materials:

[0088] The process is substantially the same as Example 1, except that polyether polyamide block polymer B is used instead of polyether polyamide block polymer A.

[0089] Example 5

[0090] Preparation of highly wear-resistant polyurethane materials:

[0091] The process is substantially the same as Example 1, with the only difference being that filler B is used instead of filler A.

[0092] Example 6

[0093] Preparation of highly wear-resistant polyurethane materials:

[0094] The process is substantially the same as Example 1, with the only difference being that filler C is used instead of filler A.

[0095] Example 7

[0096] Preparation of highly wear-resistant polyurethane materials:

[0097] The process is substantially the same as Example 1, with the only difference being that filler D is used instead of filler A.

[0098] Example 8

[0099] Preparation of highly wear-resistant polyurethane materials:

[0100] The process is substantially the same as Example 1, except that bis(2-hydroxyethyl)terephthalate is used instead of hydroquinone dihydroxyethyl ether as the chain extender.

[0101] Comparative Example 1

[0102] Preparation of highly wear-resistant polyurethane materials:

[0103] The process is substantially the same as Example 1, except that polyethylene glycol 2000 is used instead of polyether polyamide block polymer A.

[0104] Comparative Example 2

[0105] Preparation of highly wear-resistant polyurethane materials:

[0106] The process is substantially the same as Example 1, except that only trimethylolpropane is used as the cross-linking agent.

[0107] Test section

[0108] The relative volume wear of the polyurethane materials obtained in each embodiment and comparative example relative to the No. 1 standard reference rubber was measured in accordance with GB / T 9867-2008 "Determination of wear resistance of vulcanized rubber or thermoplastic rubber (rotating roller abrader method)". 3 The elongation at break δ (%) of the polyurethane materials obtained in each embodiment and comparative example was tested with reference to GB / T 528-2009 “Vulcanized rubber or thermoplastic rubber — Determination of tensile stress-strain properties”. The results are shown in Table 1.

[0109] Table 1

[0110]

[0111] According to Table 1, the polyurethane materials obtained in each embodiment have lower relative volume wear and higher elongation at break than the comparative examples, indicating that the highly wear-resistant polyurethane materials provided by the present application not only have good wear resistance but also good flexibility. Specifically, in Comparative Example 1, polyethylene glycol is used instead of polyether polyamide block polymer. Since it is only a flexible polyether segment, it cannot effectively form an interface connection area between the soft segment and the hard segment of the polyurethane material, and therefore cannot effectively disperse the stress to which the material is subjected, resulting in poor wear resistance and flexibility. In Comparative Example 2, trimethylolpropane is used as a crosslinking agent. However, it cannot form a regular hard segment structure within the polyurethane system, resulting in poor stability and density of the crosslinked network. Moreover, it does not contain polar segments and cannot effectively cooperate with the bridging agent to disperse the stress to which the material is subjected, resulting in poor wear resistance and flexibility.

[0112] Examples 1-3 show that using different types of trihydroxyaromatic compounds as crosslinkers has a certain impact on the wear resistance and flexibility of polyurethane materials. When a certain ratio of benzyltrimethylolamine and mesityl alcohol is used as the crosslinker, the resulting polyurethane material has better wear resistance and flexibility.

[0113] According to Examples 1 and 4, the polyether polyamide block polymers prepared using different hydroxyl-terminated polyethylene glycols have a certain impact on the wear resistance and flexibility of the polyurethane material. When the polyether polyamide block polymer prepared using dihydroxyl-terminated polyethylene glycol is used as a bridging agent, the resulting polyurethane material has better wear resistance and flexibility.

[0114] Examples 1, 5, and 7 show that the use of different fillers has a certain impact on the wear resistance and flexibility of polyurethane materials. When a certain ratio of imidazole-modified flaky fillers and imidazole-modified spherical fillers is used, the resulting polyurethane material has better wear resistance and flexibility.

[0115] According to Examples 1 and 8, the use of different types of chain extenders has a certain impact on the wear resistance and flexibility of the polyurethane material. When hydroquinone dihydroxyethyl ether is used as the chain extender, the resulting polyurethane material has better wear resistance and flexibility.

[0116] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the principles of the present application should be included in the scope of protection of the present application.

Claims

1. A highly wear-resistant polyurethane material, characterized in that: Including the following raw materials by weight: 100 parts of isocyanate, 60-80 parts of polyester polyol, 8-12 parts of chain extender, 6-10 parts of cross-linking agent, 5-9 parts of bridging agent, 0.5-1.5 parts of filler; The cross-linking agent comprises a trihydroxy aromatic compound, the trihydroxy aromatic compound comprises trimesoylethanolamine and mesityl alcohol, and the mass ratio of trimesoylethanolamine to mesityl alcohol is 1:1.5~2.5; the bridging agent comprises a polyether polyamide block polymer, and the polyether polyamide block polymer is obtained by co-condensation of terminal hydroxyl polyethylene glycol and ω-aminododecanoic acid.

2. The polyurethane material according to claim 1, characterized in that The molar ratio of the hydroxy-terminated polyethylene glycol to ω-aminododecanoic acid is 1:2-2.

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3. The polyurethane material according to claim 1, characterized in that The hydroxyl-terminated polyethylene glycol is a double-terminated hydroxyl-terminated polyethylene glycol, and the weight average molecular weight of the hydroxyl-terminated polyethylene glycol is 500-700.

4. The polyurethane material according to claim 1, characterized in that The filler includes an imidazole-modified filler, wherein the imidazole-modified filler is obtained by modifying an inorganic filler with an imidazole-silane coupling agent.

5. The polyurethane material according to claim 4, characterized in that The inorganic filler includes a flake filler and a spherical filler, and the mass ratio of the flake filler to the spherical filler is 2-3:

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6. The polyurethane material according to claim 1, characterized in that The chain extender includes a dihydroxy aromatic compound, and the dihydroxy aromatic compound includes hydroquinone dihydroxyethyl ether.

7. The polyurethane material according to any one of claims 1 to 6, characterized in that: The polyurethane material satisfies at least one of the following conditions: 1) The isocyanate includes at least one of toluene diisocyanate and diphenylmethane diisocyanate; 2) The polyester polyol includes polycaprolactone diol, and the weight average molecular weight of the polycaprolactone diol is 800-2000; 3) The raw materials further include 0.1 to 0.5 parts of an organotin catalyst.

8. A method for preparing a highly wear-resistant polyurethane material, characterized in that: The following steps are involved: Providing a raw material for the polyurethane material according to any one of claims 1 to 7; The raw materials are mixed and then cured to obtain a polyurethane material.

9. A wear-resistant product, characterized in that: The invention comprises the polyurethane material according to any one of claims 1 to 7 or the polyurethane material prepared by the method according to claim 8.

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