High-wear-resistance polyurethane material and preparation method thereof

Abstract

The invention provides a high-wear-resistance polyurethane material and a preparation method thereof.The polyurethane material is prepared from, by mass, 100 parts of isocyanate, 60-80 parts of polyester polyol, 8-12 parts of a chain extender, 6-10 parts of a cross-linking agent, 5-9 parts of a 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. A trihydroxy aromatic compound with three degrees of functionality and a rigid structure is introduced into a polyurethane system and is cooperatively matched with a polyether polyamide block polymer with a polar chain segment and a flexible chain segment, so that a molecular system with a rigid enhanced network and a flexible connection structure is constructed; while the structural stability and the wear resistance of the hard segment are improved, the problem of insufficient flexibility caused by high cross-linking density or chain segment stiffening in the traditional high-wear-resistance polyurethane is effectively relieved, so that the polyurethane material has both wear resistance and flexibility.

Description

Technical Field

[0001] This 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] Due to its excellent mechanical properties, wear resistance, elasticity and processing adaptability, polyurethane materials have been widely used in wear-resistant components such as shoe soles, seals, conveyor belts, and industrial rollers. In particular, thermosetting polyurethanes formed by the reaction of diisocyanates, polyols and chain extenders can achieve customized performance regulation by adjusting the ratio of soft segments to hard segments. However, in order to simultaneously achieve high wear resistance and good flexibility, higher requirements are put forward for the microstructure of polyurethane materials.

[0003] To improve the wear resistance of polyurethane, in the prior art, methods such as increasing the proportion of hard segments, increasing the crosslinking density or introducing inorganic fillers are mainly used to strengthen the surface rigidity of the material. These methods have improved the anti-cutting and anti-friction capabilities to a certain extent, but they have also brought the problem of overall rigidification of the material, resulting in a decrease in its flexibility and ductility, and limiting its adaptability in high-deformation scenarios. On the other hand, to improve flexibility, plasticization modification or increasing the proportion of soft segments are often used, but these methods often come at the cost of wear resistance and it is 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 light fillers and nano-fillers and combining polyols, isocyanates and small molecule chain extenders to construct the main chain structure, good tensile strength and wear resistance are achieved. This scheme is based on the in-situ modification polymerization strategy of prepolymers, and the film-forming and curing reaction paths are designed in components A / B respectively, which is suitable for the wear-resistant protection requirements in coating applications. However, the dominant feature of hard segments is still obvious in this type of formulation system, and there is still room for further optimization in its structural design in scenarios with high flexibility and deformation adaptability requirements.

[0005] Therefore, there is still room for improvement in the comprehensive performance of existing polyurethane materials. 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, this 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 can achieve both high wear resistance and good flexibility in terms of structure. By synergistically designing the chain extender, crosslinking agent, bridging agent and filler system, 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 raw materials in the following parts by mass: 100 parts of isocyanate, 60 - 80 parts of polyester polyol, 8 - 12 parts of chain extender, 6 - 10 parts of crosslinking agent, 5 - 9 parts of bridging agent, and 0.5 - 1.5 parts of filler; wherein, the crosslinking 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 cooperating with a polyether-polyamide block polymer having polar segments and flexible segments, a molecular system with both a rigid enhanced network and a flexible connection structure is constructed. While improving the stability of the hard segment structure and the wear resistance, the problem of insufficient flexibility caused by high crosslinking density or chain segment stiffening in traditional highly wear-resistant polyurethanes is effectively alleviated, enabling the polyurethane material to balance wear resistance and flexibility.

[0009] Specifically, the isocyanate, as a reaction component of the polyurethane main chain, provides -NCO functional groups to react with polyol components to form a basic polyurethane backbone structure, and regulates the crosslinking degree and mechanical strength of the material; the polyester polyol, as a source of flexible segments, provides segment slip ability and deformation space in the polyurethane system after introduction, which helps to improve the overall flexibility and ductility of the material; the chain extender participates in the construction of the main chain as a chain growth monomer, enhancing the integrity and continuity of the polyurethane hard segment structure and providing the basic strength support required 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 formation of stable microcrystalline phase separation in the polyurethane hard segment, 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. It can form an interfacial connection region between the soft segment and the hard segment, providing a stress transfer effect, guiding the segment distribution and stress dispersion during the process of receiving external mechanical stress, and enhancing the flexible response ability of the system.

[0010] It should be noted that the crosslinking agent constructs a stable hard segment connection structure to form the strength framework of the polyurethane material; the bridging agent adjusts the interfacial transition between the soft segment and the hard segment, buffers the local rigidity concentration caused by the crosslinking density, and stabilizes the microphase distribution. The two cooperate to construct a composite network structure in which a rigid enhanced structure and flexible transition segments coexist, enabling the polyurethane material provided by the present invention to effectively improve flexibility while maintaining high wear resistance. The filler is dispersed in the matrix in a low addition amount, improving the surface wear resistance of the material, and acting together with the crosslinking structure and the bridging structure to enhance the interfacial stability and overall structural consistency of the polyurethane.

[0011] Through the collaborative design and construction of the above components, the polyurethane material provided by this application forms a multi-scale structural network supported by a rigid reinforcement structure, flexible connecting chain segments, and dispersed reinforcing fillers. While improving the wear resistance, it significantly enhances the overall flexibility, making it suitable for application scenarios that require both surface abrasion resistance and deformation adaptability.

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

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

[0014] Specifically, both mellitoyl ethanolamine and mesityl alcohol have a symmetric aromatic structure, with regular molecular configurations and uniform functional group distributions. They can more effectively serve as the induced crystallization centers of the microphase structure, promoting the formation of ordered microcrystalline regions of polyurethane hard segments. During the crosslinking reaction, a multi-point crosslinked network with clear directions and symmetric structures can be formed, which helps to improve the microdomain structure density and dimensional retention ability. Among them, due to the introduction of amide-type side chains in the molecular structure of mellitoyl ethanolamine, a certain polar structural unit can still be retained after the formation of crosslinking points, and it has strong interfacial compliance ability; while mesityl alcohol has a higher structural rigidity and stronger induced stacking ability, which is more conducive to the regular arrangement of microdomain crosslinking points. This compound crosslinking design constructs a stable and flexible crosslinked network structure by combining the consistent aromatic nucleus regularity and complementary functional characteristics, enabling the polyurethane system to enhance the stability and wear resistance of the hard segments while retaining the necessary chain segment movement space, further improving the flexibility of the material.

[0015] It should be noted that the amide-type structure introduced by mellitoyl ethanolamine can also form hydrogen bonds or polar synergistic effects with the polyamide segment in the polyether-polyamide block polymer, constructing a microscopic synergistic anchoring network between the crosslinking point region and the bridging structure, enhancing the stability of the bridging chain segments at the interface, preventing the structure from de-embedding or breaking under load, and improving the stress response consistency and energy dissipation ability of the material.

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

[0017] In some of the above embodiments, by using polyethylene glycol with a hydroxyl - terminated structure as the limiting flexible chain segment and carrying out a polycondensation reaction with ω - aminododecanoic acid having both amino and carboxyl functional groups, a block structure containing both a flexible polyether chain segment and a polar polyamide chain segment is constructed in the resulting cross - linker molecule. The hydroxyl - terminated polyethylene glycol can be a double - end or single - end hydroxyl - terminated structure, which provides reaction sites or chain - length control functions in the polycondensation reaction, helps to limit the polymer molecular weight, regulate the structural ratio and the distribution of flexible segments.

[0018] After introducing the obtained polyether - polyamide block polymer as a cross - linker into the polyurethane system, its polyamide segment can enhance the interfacial affinity with the polar region or cross - link points in the structure, form physical entanglements or hydrogen - bond networks, and improve the stability of the hard - segment connection region; the polyether segment can also play a role in regulating inter - chain connection, compatibility transition and stress dispersion in the structure, thereby endowing the system with better chain - segment slippage ability and structural flexibility.

[0019] Meanwhile, when the molar ratio of hydroxyl - terminated polyethylene glycol to ω - aminododecanoic acid is controlled at 1:2 - 2.5, it can control the resulting cross - linker to maintain an appropriate molecular weight and block ratio in the structure, ensuring both sufficient polar - block anchoring ability and preventing problems such as processing difficulties and reduced compatibility caused by overly long molecular chain segments. Finally, a dual function of flexible regulation and interface stabilization is achieved in the cross - linker structure, thereby achieving a better stress - transfer effect and further enhancing the flexibility of the polyurethane material without sacrificing wear resistance.

[0020] In some embodiments, the hydroxyl - terminated polyethylene glycol is double - end hydroxyl - terminated 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 polycondensation reaction with ω - aminododecanoic acid, but also retains one - end hydroxyl as a reaction site to react with isocyanate in the subsequent polyurethane synthesis and be incorporated into the main chain to form a covalent cross - link structure; this structural design enables the cross - linker to have the synergistic function of flexible and polar segments while also having the ability to be embedded in the main chain, significantly enhancing its stability and anchoring force in the interfacial region. Through this covalent incorporation mechanism, the cross - linker not only undertakes the stress transition and flexible regulation between chain segments in the polyurethane system, but also can form a continuous structural connection with the main chain, avoiding phenomena such as chain - segment slippage, uneven dispersion or interfacial de - embedding that may occur in the case of physical doping, thereby further enhancing the coordination of the force response of the system.

[0022] Compared with the crosslinking agent without main-chain reaction activity, the structural crosslinking agent constructed using dihydroxy polyethylene glycol has stronger anchoring effect and structural integration degree. Especially under stress, it can stably maintain the functional role of the crosslinked structure in the system, so as to further improve the flexibility of the polyurethane material while maintaining the wear resistance.

[0023] Meanwhile, the molecular weight of the dihydroxy polyethylene glycol is controlled within the range of 500 - 700. The dihydroxy polyethylene glycol within this molecular weight range has good melt fluidity and reaction activity, and can efficiently construct a polyether-polyamide structure and form a crosslinking agent with an appropriate chain length, enabling it to better play the triple functions of structural connection, flexibility adjustment, and polar anchoring in the polyurethane system, so that the polyurethane material can better balance wear resistance and flexibility.

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

[0025] In the above-mentioned some embodiments, by surface-modifying the inorganic filler with a silane coupling agent containing an imidazole group, an imidazole functional group with a polar structure can be introduced on the filler surface, making it have better dispersibility and interfacial binding force in the polyurethane system. The imidazole group molecule contains a heterocyclic structure, has high polarity, high electron density, and multi-point coordination ability, and can form hydrogen bonds, π–π stacking, or electrostatic interactions with structures such as amide, urea, and aromatic rings in the polyurethane system to construct a stable interfacial binding network.

[0026] Compared with common amino, carboxyl, or alkoxy functional groups, the imidazole-based structure has stronger polar interaction ability and intermolecular compatibility, and can achieve closer polar entanglement and structural synergy in the micro-region of the polyurethane hard segment, improving the anchoring stability of the filler in the interfacial region; 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 can be understood that the imidazole-based modified filler and the crosslinking agent (trimellitic acid ethanolamide) or crosslinking agent (polyamide segment) containing a polar structure can form multi-point polar synergy to construct a stable cooperative anchoring network in the filler-polymer interfacial region, which helps to relieve stress concentration and local interfacial discontinuity problems. Compared with unmodified fillers or modified fillers grafted with conventional groups, imidazole-based fillers are more conducive to improving the interfacial energy dissipation ability and structural continuity, and further improving the flexibility while enhancing the wear resistance of the material.

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

[0029] In some of the above embodiments, by using flaky fillers and spherical fillers with different morphological structures and reinforcement mechanisms in combination, a multi-scale synergistic reinforcement structure can be constructed inside the polyurethane material. Among them, the flaky fillers have a large specific surface area and two-dimensional structural characteristics. After dispersion, they can be arranged in the matrix along the plane direction to form a slip guiding layer and a crack deflection channel, effectively extending the crack propagation path and enhancing the surface shear resistance and overall wear resistance stability. The spherical filler particles are uniform and have good rigidity, which can play a role in structural support, gap filling, and dispersion stability in the system, avoiding the agglomeration effect caused by stacking between flaky fillers, and at the same time alleviating the damage to the flexibility of the material due to sudden changes in micro-rigidity.

[0030] At the same time, the mass ratio of the two is controlled within the range of 2-3:1, so that the flaky fillers play a dominant role in the system, thus giving full play to their ability to construct a slip layer and an anti-crack structure. At the same time, an appropriate amount of spherical fillers is added to construct a structural transition and dispersion assistance function through point support, improving the structural uniformity and flexibility foundation while maintaining the reinforcement effect, so as to effectively maintain the flexibility of the polyurethane material while improving the wear resistance of the material.

[0031] In some embodiments, the average sheet diameter of the flaky filler is 1-10 μm, and the average thickness is 10-100 nm; the average particle diameter of the spherical filler is 5-20 μm. As an example, in an embodiment of the present application, flaky montmorillonite with an average sheet diameter of 5 μm and an average thickness of 60 nm is used as the flaky filler, and silica particles with an average particle diameter of 10 μm are used as the spherical filler.

[0032] In some embodiments, the chain extender includes a dihydroxy aromatic compound, and the dihydroxy aromatic compound includes hydroquinone bis(2-hydroxyethyl) ether.

[0033] In some of the above embodiments, the hydroquinone bis(2-hydroxyethyl) ether molecule contains a symmetric aromatic ring structure and terminal hydroxyl functional groups, and can participate in the construction of hard segments as a chain growth monomer in the polyurethane polymerization reaction. Its central aromatic ring provides good regularity and rigid support, and the two terminal ethylene glycol segments have certain flexibility and adjustable spacing, which helps to construct a hard segment structure with consistent direction and appropriate chain segment length, improving the microphase regularity and chain segment connection continuity of the polyurethane system.

[0034] In this embodiment, this chain extender is used. On the one hand, it can jointly construct a hard segment skeleton with a consistent structural style with aromatic isocyanates and aromatic crosslinking agents, improving the dimensional stability and shear resistance of the material. On the other hand, its two terminal flexible ethylene glycol segments introduce locally deformable buffer segments in the hard segment connection area, which can establish a soft connection transition between the rigid structure and the flexible structure, relieve the stress concentration caused by sudden changes in rigidity, and improve the stress transfer efficiency between structural regions.

[0035] In addition, the flexible chain segment also helps to enhance the compatibility with flexible structures such as crosslinking agents, forming a smooth transition between the crosslinked network and the bridging network, and improving the interfacial coordination of the entire system. Compared with chain extenders with overly soft or rigid structures, the chain segment constructed by hydroquinone di(2-hydroxyethyl) ether can better maintain its flexibility while improving the wear resistance of polyurethane materials.

[0036] In some embodiments, the isocyanate includes at least one of toluene diisocyanate and diphenylmethane diisocyanate. Based on the above embodiments, as aromatic isocyanates, toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI) have good reactivity and structural rigidity, and can jointly construct a backbone structure with strong hard segment regularity and high thermal stability with aromatic chain extenders and crosslinking agents, which is the basic composition for achieving the wear resistance of polyurethane.

[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, as a preferred source of flexible chain segments in polyester polyols, polycaprolactone diol has high chain segment flexibility and good polar compatibility. Controlling the molecular weight within the range of 800-2000 can not only ensure that the chain segment is soft enough, but also maintain the reaction efficiency and mechanical balance of the system, which helps to maintain the flexibility of polyurethane materials.

[0038] In some embodiments, the raw materials further include 0.1-0.5 parts of an organotin catalyst. Based on the above embodiments, introducing an organotin catalyst, such as stannous octoate and dibutyltin dilaurate, can significantly increase the reaction rate between isocyanate and hydroxyl components, ensuring that multi-functional components such as crosslinking agents, chain extenders, and crosslinking agents in the system can fully react, and avoiding network discontinuity or local performance degradation caused by incomplete reactions.

[0039] In a second aspect, the present application provides a method for preparing a high-wear-resistant polyurethane material, including the following steps: Providing the raw materials of the polyurethane material according to any one of the embodiments of the first aspect; Mixing the raw materials and then curing to obtain a polyurethane material.

[0040] According to the present application, the method is based on a raw material system with clear functional structures. The polymerization process does not require complex reaction control conditions, and a polyurethane material structure network with high crosslinking stability and interfacial synergy can be formed through conventional mixing and curing steps. Each raw material component has good reaction matching and polar compatibility in the molecular structure, and can be incorporated into the system synergistically during the reaction process to construct a rigid hard segment network, a flexible chain segment buffer zone, and a multi-point interface anchoring structure.

[0041] This method has the advantages of simple operation, strong adaptability, high system uniformity, etc. The prepared polyurethane material exhibits excellent wear resistance and flexibility, and is suitable for a variety of application scenarios with dual requirements for material wear resistance and deformation adaptability.

[0042] In some embodiments, the method specifically includes: adding components such as polyester polyol, bridging agent, chain extender, crosslinking agent, filler, etc. into a mixing container according to a predetermined ratio, and premixing at 60-90°C for 30-60 min under stirring conditions to fully disperse and mix all kinds of raw materials evenly; preferably, the bridging agent and crosslinking agent can be premixed with the polyester polyol first to form a good distribution state in the system; Under the condition of nitrogen protection, the isocyanate component is heated to the molten state at 60-70°C and then slowly added into the mixing system, and the stirring reaction is continued for 20-30 min to form a uniform prepolymer mixture; After pouring the reaction mixture into a mold, it is placed in an environment of 80-120°C for curing for 3-5 h to complete reaction molding. After cooling and demolding, the polyurethane material is obtained.

[0043] In a third aspect, the present application provides a wear-resistant product, which includes the polyurethane material according to any one of the embodiments of the first aspect, or the polyurethane material prepared by the method described in the second aspect.

[0044] According to the present application, the polyurethane material enhances through a crosslinked structure, adjusts through a bridging structure, and synergizes with a filler structure to construct a composite network structure with coexistence of rigidity and flexibility, stable interface, and uniform stress dispersion at the molecular scale, having excellent wear resistance and flexibility, and being suitable for preparing a variety of wear-resistant products that withstand repeated friction, shear, extrusion, or deformation.

[0045] The wear-resistant polyurethane material described in the present application can be processed and formed into structural components such as seals, conveyor belt coverings, soles, shock pads, roller rubber coatings, coating films, or elastic wear-resistant linings, etc. During use, it can not only maintain good wear resistance stability and reduce the material wear rate, but also maintain flexible response and structural integrity in a deformed environment. Compared with the problems of peeling and cracking of conventional highly crosslinked polyurethane materials due to increased brittleness, the polyurethane material of the present application significantly improves the actual application life and processing adaptability of wear-resistant products through the collaborative design of flexible chain segments and structures.

[0046] Compared with the prior art, the beneficial effects of the present application are at least as follows: By co - designing cross - linkers, bridging agents, chain extenders and filler structures, a composite network system with a rigid reinforcement structure, flexible connecting chain segments and multi - scale interface synergy is constructed in polyurethane materials. Without relying on complex processes, the synergistic improvement of the wear resistance and flexibility of polyurethane materials is achieved, which is more suitable for application scenarios that require both surface wear and deformation adaptability. Detailed implementation manners

[0047] In order to make the objectives, technical solutions and advantages of this application clearer, the following further details this application in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0048] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of this application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0049] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this application, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0050] In this application, unless otherwise specified, "parts" all refer to "parts by mass".

[0051] The following explains the solution of this application in conjunction with the following specific embodiments. Unless otherwise specified, the raw materials used in the following embodiments are all from ordinary commercially available products, and the devices or equipment used are all purchased from conventional market sales channels.

[0052] Flaky montmorillonite: The average sheet diameter is 5 μm and the average thickness is 60 nm; Silica particles: The average particle diameter is 10 μm.

[0053] Preparation Example 1 - 1 Preparation of polyether - polyamide block polymer: Put the hydroxyl-terminated polyethylene glycol with a weight-average molecular weight of 600 and ω-aminolauric acid directly into a reaction kettle, control the molar ratio of the two to be 1:2.2, add 1% dibutyltin dilaurate and 0.5% dibutylhydroxytoluene based on the mass percentage of the reactants; react at 150 °C for 5 h under stirring conditions to obtain the polyether-polyamide block polymer A.

[0054] Preparation Example 1-2 Preparation of polyether-polyamide block polymer: Put the hydroxyl-terminated polyethylene glycol with a weight-average molecular weight of 600 and ω-aminolauric acid directly into a reaction kettle, control the molar ratio of the two to be 1:2.2, add 1% dibutyltin dilaurate and 0.5% dibutylhydroxytoluene based on the mass percentage of the reactants; react at 150 °C for 5 h under stirring conditions to obtain the polyether-polyamide block polymer B.

[0055] Preparation Example 2-1 Preparation of filler: Disperse 10 parts of inorganic filler (flake montmorillonite and silica particles with a mass ratio of 2.5:1) in 200 parts of a mixed solution of ethanol and water with a volume ratio of 70 / 30, ultrasonically disperse for 20 min, then add 1 part of N-(trimethoxysilylpropyl)imidazole, heat and reflux at 70 °C for 3 h, after the reaction, centrifuge and wash 3 times with water, and vacuum dry at 50 °C to obtain the imidazole-based modified filler as filler A.

[0056] Preparation Example 2-2 Preparation of filler: Similar to Preparation Example 2-1, the difference is only that: the inorganic filler is flake montmorillonite, and the imidazole-based modified filler is obtained as filler B.

[0057] Preparation Example 2-3 Preparation of filler: Similar to Preparation Example 2-1, the difference is only that: the inorganic filler is silica particles, and the imidazole-based modified filler is obtained as filler C.

[0058] Preparation Example 2-4 Preparation of filler: Similar to Preparation Example 2-1, the difference is only that: γ-aminopropyltriethoxysilane is used instead of N-(trimethoxysilylpropyl)imidazole, and the amino-modified filler is obtained as filler D.

[0059] Example 1

[0060] Preparation of high wear-resistant polyurethane material: 70 parts of polycaprolactone diol with a weight-average molecular weight of 1200 were mixed evenly with 10 parts of hydroquinone di(2-hydroxyethyl) ether and stirred and dissolved at 50 °C; then 8 parts of a crosslinking agent (trimellitic acid ethanolamide and trimesic alcohol in a mass ratio of 1:2) and 7 parts of polyether-polyamide block polymer A were added and stirring was continued for dispersion; the temperature was then raised to 70 °C, 1 part of filler A was added and ultrasonic dispersion was carried out evenly; then 100 parts of diphenylmethane diisocyanate were heated and melted at 65 °C and slowly added to the above mixture, and the reaction was carried out at 70 °C for 30 min to obtain a polyurethane prepolymer; then 0.3 part of dibutyltin dilaurate was added to the polyurethane prepolymer and transferred to a mold, and curing reaction was carried out by heating at 100 °C for 4 h. After curing was completed, it was cooled and demolded to obtain a polyurethane material.

[0061] Example 2

[0062] Preparation of a highly wear-resistant polyurethane material: It was substantially the same as Example 1, except that: only 8 parts of trimellitic acid ethanolamide were used as the crosslinking agent.

[0063] Example 3

[0064] Preparation of a highly wear-resistant polyurethane material: It was substantially the same as Example 1, except that: only 8 parts of trimesic alcohol were used as the crosslinking agent.

[0065] Example 4

[0066] Preparation of a highly wear-resistant polyurethane material: It was substantially the same as Example 1, except that: polyether-polyamide block polymer B was used instead of polyether-polyamide block polymer A.

[0067] Example 5

[0068] Preparation of a highly wear-resistant polyurethane material: It was substantially the same as Example 1, except that: filler B was used instead of filler A.

[0069] Example 6

[0070] Preparation of a highly wear-resistant polyurethane material: It was substantially the same as Example 1, except that: filler C was used instead of filler A.

[0071] Example 7

[0072] Preparation of a highly wear-resistant polyurethane material: It was substantially the same as Example 1, except that: filler D was used instead of filler A.

[0073] Example 8

[0074] Preparation of a highly wear-resistant polyurethane material: It is substantially the same as Example 1, except that bis(2-hydroxyethyl) terephthalate is used instead of hydroquinone bis(2-hydroxyethyl) ether as the chain extender.

[0075] Comparative Example 1 Preparation of a highly wear-resistant polyurethane material: It is substantially the same as Example 1, except that polyethylene glycol 2000 is used instead of the polyether-polyamide block polymer A.

[0076] Comparative Example 2 Preparation of a highly wear-resistant polyurethane material: It is substantially the same as Example 1, except that only trimethylolpropane is used as the crosslinking agent.

[0077] Test section The relative volume wear amount ΔV mm of the polyurethane materials obtained in each example and comparative example with respect to the No. 1 standard reference rubber was tested with reference to GB / T 9867-2008 "Determination of abrasion resistance of vulcanized rubber or thermoplastic rubber (rotating roller abrader method)". 3 ; The elongation at break δ (%) of the polyurethane materials obtained in each example and comparative example was tested with reference to GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber". The results are shown in Table 1.

[0078] Table 1

[0079] According to Table 1, the polyurethane materials obtained in each example have lower relative volume wear amounts and higher elongation at break compared to each comparative example, indicating that the highly wear-resistant polyurethane material provided in this application not only has good wear resistance but also good flexibility. Specifically, in Comparative Example 1, polyethylene glycol was used instead of the polyether-polyamide block polymer. Since it only has flexible polyether chain segments, it cannot effectively form an interfacial connection region between the soft and hard segments of the polyurethane material, so it cannot well disperse the stress received by the material, resulting in poor wear resistance and flexibility; in Comparative Example 2, trimethylolpropane was used as the crosslinking agent, which cannot form a regular hard segment structure in the polyurethane system, resulting in poor stability and compactness of the crosslinking network, and it does not contain polar chain segments, so it cannot effectively cooperate with the bridging agent to disperse the stress received by the material, resulting in poor wear resistance and flexibility.

[0080] According to Examples 1 to 3, it can be seen that using different types of trihydroxyaromatic compounds as crosslinking agents has a certain influence on the wear resistance and flexibility of the polyurethane material. When using a certain proportion of benzoyl ethanolamine and mesitylene triol as the crosslinking agent, the obtained polyurethane material has better wear resistance and flexibility.

[0081] According to Examples 1 and 4, it can be seen that the polyether-polyamide block polymers prepared using different hydroxyl-terminated polyethylene glycols have a certain influence on the wear resistance and flexibility of polyurethane materials. When the polyether-polyamide block polymer prepared using hydroxyl-terminated polyethylene glycol with two ends is used as a cross-linking agent, the obtained polyurethane material has better wear resistance and flexibility.

[0082] According to Examples 1, 5 to 7, it can be seen that using different types of fillers has a certain influence on the wear resistance and flexibility of polyurethane materials. When using a certain proportion of imidazole-group modified flaky fillers and imidazole-group modified spherical fillers, the obtained polyurethane material has better wear resistance and flexibility.

[0083] According to Examples 1 and 8, it can be seen that using different types of chain extenders has a certain influence on the wear resistance and flexibility of polyurethane materials. When using hydroquinone bis(2-hydroxyethyl) ether as a chain extender, the obtained polyurethane material has better wear resistance and flexibility.

[0084] The above are only the preferred embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the principle of the present application shall be included within the protection scope of the present application.

Claims

1. A highly wear-resistant polyurethane material, characterized in that, Comprising the following raw materials in parts by mass: 100 parts of isocyanate, 60 - 80 parts of polyester polyol, 8 - 12 parts of chain extender, 6 - 10 parts of crosslinking agent, 5 - 9 parts of bridging agent, 0.5 - 1.5 parts of filler; Wherein, the crosslinking agent comprises a trihydroxy aromatic compound, and the bridging agent comprises a polyether polyamide block polymer.

2. The polyurethane material according to claim 1, wherein The trihydroxy aromatic compound comprises trimellitic acid ethanolamine and mesitylene triol, and the mass ratio of trimellitic acid ethanolamine to mesitylene triol is 1:1.5 - 2.

5.

3. The polyurethane material according to claim 1, wherein The polyether polyamide block polymer is obtained by co - polycondensation of terminal - hydroxyl polyethylene glycol and ω - aminolauric acid, wherein the molar ratio of terminal - hydroxyl polyethylene glycol to ω - aminolauric acid is 1:2 - 2.

5.

4. The polyurethane material according to claim 3, wherein The terminal - hydroxyl polyethylene glycol is a double - terminal - hydroxyl - capped polyethylene glycol, and the weight - average molecular weight of the terminal - hydroxyl polyethylene glycol is 500 - 700.

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

6. The polyurethane material according to claim 5, wherein, The inorganic filler comprises a flaky filler and a spherical filler, and the mass ratio of the flaky filler to the spherical filler is 2 - 3:

1.

7. The polyurethane material according to claim 1, characterized in that, The chain extender comprises a dihydroxy aromatic compound, and the dihydroxy aromatic compound comprises hydroquinone di - hydroxyethyl ether.

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

9. A method for preparing a highly wear-resistant polyurethane material, characterized in that, Comprising the following steps: Providing the raw materials of the polyurethane material according to any one of claims 1 - 8; Mixing the raw materials and curing to obtain a polyurethane material.

10. A wear-resistant article, characterized in that, Comprising the polyurethane material according to any one of claims 1 - 8 or the polyurethane material prepared by the method according to claim 9.

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