A core-shell structure coated pigment wear-resistant masterbatch, a preparation method and application thereof

Abstract

This application discloses a core-shell structured coated pigment wear-resistant masterbatch, its preparation method, and its application. The masterbatch comprises the following raw materials in parts by weight: 50-75 parts carrier resin, 25-50 parts core-shell structured pigment, and 0.5-2 parts dispersant. The core-shell structured pigment consists of an inorganic pigment core and a functional shell layer coated on the surface of the inorganic pigment core. The functional shell layer is made of modified nano-silicone resin or a polymer-modified two-dimensional layered solid lubricating material. The carrier resin is thermoplastic polyurethane. This application coats the surface of the inorganic pigment core with a functional shell layer, fundamentally preventing pigment agglomeration and achieving nanoscale uniform dispersion and strong interfacial bonding in the thermoplastic polyurethane matrix. This imparts bright and stable color to the product while avoiding stress concentration defects caused by pigment agglomeration, thereby improving the mechanical properties of the masterbatch.

Description

Technical Field

[0001] This application relates to the field of polymer material coloring and modification technology, and in particular to a core-shell structured coated pigment wear-resistant masterbatch, its preparation method and application. Background Technology

[0002] Thermoplastic polyurethane is widely used in industrial casters, conveyor belts, seals, automotive parts, and electronic product protective cases due to its excellent elasticity, abrasion resistance, oil resistance, and mechanical strength. In practical applications, color masterbatches are often added to give the products a rich variety of colors.

[0003] However, traditional masterbatches are usually made by simply mixing pigments and carrier resins mechanically. For thermoplastic polyurethane systems, especially high-hardness thermoplastic polyurethane, the compatibility with inorganic pigment particles is poor, which makes it difficult for pigments to be evenly dispersed in the matrix and they are prone to agglomeration. These pigment agglomerates will form stress defect points in composite materials, which will lead to a series of key technical problems: (1) During the friction process, the agglomerated pigment particles, as weak points, will preferentially peel off from the matrix, resulting in abrasive wear and significantly accelerating material loss; (2) The weak bonding between pigment and resin interface affects stress transmission, which leads to a decrease in the tensile strength, tear strength and other mechanical properties of thermoplastic polyurethane products; (3) The uneven surface of the material and the detached pigment abrasive will increase the friction coefficient between thermoplastic polyurethane and the mating parts (such as steel) and increase the fluctuation, making it difficult to meet the application scenarios with precise requirements for dynamic friction performance (such as precision conveyor rollers, low-noise gears); (4) Uneven pigment dispersion is prone to causing color difference, graying or decreased gloss and other appearance defects in the products.

[0004] To improve the tribological properties of thermoplastic polyurethane, existing technologies typically employ the addition of lubricants (such as silicones and waxes) or solid wear-resistant agents (such as molybdenum disulfide and graphite). However, this approach has significant limitations: firstly, the added lubricating / wear-resistant components are independent of the coloring system, which can easily cause interference, potentially leading to uneven coloring or unstable performance; secondly, the introduction of these additives may impair the transparency or other mechanical properties of thermoplastic polyurethane, and fails to fundamentally address the core issues of pigment agglomeration and weak interfacial bonding.

[0005] Therefore, there is an urgent need to develop a color masterbatch that can simultaneously achieve excellent coloring without damaging or even improving the wear resistance and low friction properties of thermoplastic polyurethane matrix. Summary of the Invention

[0006] To address the aforementioned technical problems, this application provides a core-shell structured coated pigment wear-resistant masterbatch, its preparation method, and its application.

[0007] In a first aspect, this application provides a core-shell structured coated pigment wear-resistant masterbatch, employing the following technical solution: A core-shell structured coated pigment wear-resistant masterbatch comprises the following raw materials in parts by weight: 50-75 parts carrier resin, 25-50 parts core-shell structured pigment, and 0.5-2 parts dispersant; the core-shell structured pigment consists of an inorganic pigment core and a functional shell layer coated on the surface of the inorganic pigment core; the functional shell layer is made of modified nano-silicone resin or a polymer-modified two-dimensional layered solid lubricating material; the carrier resin is thermoplastic polyurethane.

[0008] By adopting the above technical solution, this application constructs a "core-shell" structure, firmly coating the surface of the inorganic pigment core with a functional shell layer (modified nano-silicone resin or polymer-modified two-dimensional layered solid lubricant material). This fundamentally prevents pigment agglomeration, achieving nanoscale uniform dispersion and strong interfacial bonding within the thermoplastic polyurethane matrix. This imparts a bright and stable color to the product while avoiding stress concentration defects caused by pigment agglomeration, ensuring effective load transfer in the composite material and thus improving the mechanical properties of the masterbatch. Simultaneously, the modified nano-silicone resin shell layer or the polymer-modified two-dimensional layered solid lubricant material shell layer can possess both reinforcing and lubricating properties, reducing the dynamic friction coefficient of the composite material against steel and other mating parts, and significantly improving its wear resistance, effectively reducing frictional losses. Furthermore, using thermoplastic polyurethane as the carrier resin ensures compatibility and dispersibility with the product matrix, avoiding interfacial problems caused by incompatibility between the carrier and the matrix.

[0009] Optionally, the preparation steps of coating the surface of the inorganic pigment core with the modified nano-silicone resin include: mixing the inorganic pigment core and solvent, ultrasonically dispersing, adding a first silane coupling agent, heating and stirring, adding tetraethyl orthosilicate and a second silane coupling agent, then adding a catalyst, stirring evenly, centrifuging, washing, and drying to obtain a core-shell structured pigment; the second silane coupling agent is a fluorinated alkyl or long-chain alkyl silane coupling agent.

[0010] By employing the above-mentioned technical solution, a modified organic-inorganic hybrid nano-silica resin shell can be constructed in situ on the surface of an inorganic pigment core through a co-hydrolysis-condensation reaction of a second silane coupling agent containing fluorinated alkyl or long-chain alkyl groups and tetraethyl orthosilicate. This shell is firmly bonded to the pigment core through chemical bonds, and its exposed fluorinated alkyl or long-chain alkyl groups can significantly reduce surface energy. This achieves uniform nanoscale dispersion of the pigment, avoids agglomeration to maintain the mechanical properties of the matrix, and simultaneously imparts excellent surface lubrication properties to the masterbatch.

[0011] Furthermore, the first silane coupling agent is γ-aminopropyltriethoxysilane, the second silane coupling agent is heptadecafluorodecyltrimethoxysilane, the solvent is an aqueous ethanol solution, and the catalyst is ammonia.

[0012] By adopting the above technical solution, γ-aminopropyltriethoxysilane is selected as the first silane coupling agent. Its amino groups can efficiently form chemical bonds with the surface of the inorganic pigment core, achieving stable and uniform surface amination activation, providing a strong and highly reactive anchoring point for the subsequent in-situ growth of the shell layer. Heptadecafluorodecyltrimethoxysilane is selected as the second silane coupling agent. Its long fluorocarbon chain structure, during co-hydrolysis-condensation with tetraethyl orthosilicate, can uniformly and densely introduce a large number of low surface energy fluoroalkyl groups into the hybrid silica network in the form of chemical bonds. The resulting shell structure is dense and firmly bonded, with a surface rich in fluorocarbon groups. Thus, while achieving ultra-dispersion of pigments and protecting the mechanical properties of the matrix, it endows the masterbatch with extremely low surface energy, excellent hydrophobicity, and long-lasting lubrication and friction-reducing properties, ultimately enabling thermoplastic polyurethane products to obtain extremely stable and outstanding low coefficient of friction and high wear resistance. Ethanol aqueous solution provides a suitable polar environment, which can not only effectively disperse inorganic pigment cores, but also serve as a benign medium for the hydrolysis of silane coupling agents and tetraethyl orthosilicate, promoting the stable reaction in a homogeneous phase. Ammonia provides a mild alkaline environment, precisely controlling the hydrolysis and condensation rates of tetraethyl orthosilicate and the two silane coupling agents, promoting their in-situ and uniform growth into a dense organic-inorganic hybrid shell on the pigment surface.

[0013] Optionally, the polymer-modified two-dimensional layered solid lubricant is graphene or molybdenum disulfide nanosheets modified with polydopamine.

[0014] By employing the above technical solution, polydopamine is used to modify graphene or molybdenum disulfide nanosheets, endowing the two-dimensional material with two key properties: first, the strong adhesion of the polydopamine layer allows it to form an extremely strong bond with the inorganic pigment core surface through various secondary bond interactions; second, the modified nanosheet surface is rich in active groups and is charged, enabling dense and complete encapsulation through electrostatic self-assembly. The resulting core-shell structure not only prevents pigment agglomeration and ensures uniform and vibrant colors, but also makes each pigment particle an independent "micro-solid lubrication unit." The excellent interlayer slip properties of graphene or molybdenum disulfide are fully utilized, providing durable and stable lubrication at the friction interface, significantly reducing the dynamic friction coefficient of thermoplastic polyurethane composites and improving their wear resistance.

[0015] Furthermore, the preparation steps of coating the inorganic pigment core surface with the polymer-modified two-dimensional layered solid lubricant material include: mixing the inorganic pigment core and solvent, ultrasonically dispersing, adjusting the pH, adding the polymer-modified two-dimensional layered solid lubricant material, stirring evenly, filtering, washing, and drying to obtain a core-shell structured pigment.

[0016] By employing the above-mentioned technical solution, the surface charge of inorganic pigment cores is precisely controlled by adjusting the pH value, enabling them to undergo efficient electrostatic self-assembly with polydopamine-modified two-dimensional material nanosheets (such as graphene or molybdenum disulfide) carrying opposite charges. This process combines the rapid directional adsorption of electrostatics with the adhesion characteristics of polymers, ensuring that the two-dimensional material can uniformly, densely, and firmly coat the surface of each pigment core, forming a complete core-shell structure. This method not only fundamentally solves the problems of pigment dispersion and interfacial bonding, but also directly "assembles" the excellent solid lubrication properties of two-dimensional materials onto the coloring unit, thereby constructing a microscopic, uniformly distributed lubrication network in the composite material, ultimately significantly improving the wear resistance and low friction performance of thermoplastic polyurethane products.

[0017] Optionally, the inorganic pigment core is at least one of rutile titanium dioxide, iron oxide red, and phthalocyanine blue.

[0018] By adopting the above technical solution, pigments with stable chemical properties, strong tinting strength, and excellent weather resistance (rutile titanium dioxide, iron oxide red, or phthalocyanine blue) are selected as inorganic pigment cores. Their surface properties are easily functionalized by silane coupling agent treatment or electrostatic regulation, thereby forming an extremely strong bond with the subsequently constructed functional shell (modified nano-silicone resin or polymer-modified two-dimensional materials). This helps to improve the core defects of pigments in polyurethane matrix, such as easy agglomeration and weak interface.

[0019] Optionally, the average particle size of the inorganic pigment core is 0.1-1.0 μm, the thickness of the functional shell is 20-100 nm, and the melt index of the thermoplastic polyurethane is 10-50 g / 10 min.

[0020] By adopting the above technical solutions, this application selects pigment cores with a particle size of 0.1-1.0 μm, which ensures that the pigment has sufficient tinting strength and hiding power, and is conducive to its dispersion in solvent and provides a suitable specific surface area for subsequent coating reactions. The selection of a functional shell layer with a thickness of 20-100 nm can completely and densely coat the pigment core to completely isolate it from direct contact with the matrix, achieve strong interfacial bonding and functionalization, and avoid the potential negative impact of an excessively thick shell layer on the pigment's original color and the mechanical properties of the composite material. The thermoplastic polyurethane carrier with a melt index of 10-50 g / 10 min can ensure that the carrier resin has both good melt flowability and the necessary molecular weight and strength, so that the masterbatch can melt smoothly and disperse evenly during twin-screw extrusion granulation and subsequent product processing (injection molding, extrusion), and will not affect the performance of the final product due to the degradation of the carrier resin.

[0021] Optionally, the thermoplastic polyurethane is maleic anhydride-grafted thermoplastic polyurethane.

[0022] By employing the above technical solution, the maleic anhydride functional groups grafted onto thermoplastic polyurethane can chemically react with active groups such as amino groups (e.g., those from silane coupling agent KH-550) and hydroxyl groups on the surface of the core-shell structure pigment functional shell, thereby constructing covalently bonded "molecular bridges" between the carrier and the pigment during melt blending. This enhances the multi-level interfacial bonding force of the "resin-shell-pigment core," further improving the mechanical properties of the composite material; simultaneously, it enhances the structural stability of the masterbatch during processing and use, preventing performance degradation and making the wear resistance and low friction performance of the product more durable and reliable.

[0023] Optionally, it also includes 1 part by weight of silicon carbide nanosheets and 0.5 parts by weight of boron nitride nanosheets.

[0024] By adopting the above technical solution and using nano-silicon carbide and boron nitride nanosheets as functional reinforcing agents, a multi-scale composite wear-resistant system of "hard load-bearing and soft lubrication" can be constructed to synergistically improve the system's friction performance. Among them, nano-silicon carbide, as an ultra-hard nanoparticle, can effectively bear frictional loads and reduce direct wear of the matrix material; while boron nitride nanosheets, as an excellent two-dimensional solid lubricant, can further reduce the shear resistance between friction interfaces.

[0025] Optionally, the dispersant is at least one of polyethylene wax, oxidized polyethylene wax, and polyester wax.

[0026] By adopting the above technical solution and selecting polyethylene wax, oxidized polyethylene wax, or stearate as dispersants, good compatibility with thermoplastic polyurethane carrier resins can be achieved, and melt viscosity can be effectively reduced and interfacial lubrication improved. During melt blending, the dispersant can quickly coat the surface of the core-shell structure pigment, further weakening the pigment agglomeration tendency and promoting its uniform dispersion and stable distribution in the polyurethane melt. This ensures that the masterbatch has excellent processing fluidity and color uniformity, and maximizes the advantages of the core-shell structure in improving the mechanical and tribological properties of the product.

[0027] Secondly, this application provides a method for preparing a core-shell structured coated pigment wear-resistant masterbatch, employing the following technical solution: A method for preparing a core-shell structured coated pigment wear-resistant masterbatch includes the following steps: mixing a carrier resin, a core-shell structured pigment and a dispersant, stirring evenly, melting and extruding, cooling, pelletizing, and obtaining the masterbatch.

[0028] Optionally, the stirring speed is 800-1200 rpm, the melting temperature is 160-200℃, and the cooling temperature is 20-40℃.

[0029] Thirdly, this application provides the application of a core-shell structured coated pigment abrasion-resistant masterbatch in the preparation of plastic products.

[0030] In summary, this application includes at least one of the following beneficial technical effects: 1. This application constructs a "core-shell" structure, firmly coating a functional shell layer (modified nano-silicone resin or polymer-modified two-dimensional layered solid lubricant material) onto the surface of an inorganic pigment core. This fundamentally prevents pigment agglomeration, achieving nanoscale uniform dispersion and strong interfacial bonding within the thermoplastic polyurethane matrix. This imparts vibrant and stable color to the product while avoiding stress concentration defects caused by pigment agglomeration, ensuring effective load transfer within the composite material and thus improving the mechanical properties of the masterbatch. Simultaneously, the modified nano-silicone resin shell layer or the polymer-modified two-dimensional layered solid lubricant material shell layer can combine reinforcement and lubrication properties, reducing the dynamic friction coefficient of the composite material against steel and other mating parts, significantly improving its wear resistance, and effectively reducing frictional losses. 2. This application utilizes a second silane coupling agent containing fluorinated alkyl or long-chain alkyl groups to undergo a co-hydrolysis-condensation reaction with tetraethyl orthosilicate, enabling the in-situ construction of an organic-inorganic hybrid modified nano-silica resin shell on the surface of an inorganic pigment core. This shell is firmly bonded to the pigment core through chemical bonds, and its exposed fluorinated alkyl or long-chain alkyl groups significantly reduce surface energy. This achieves uniform nanoscale dispersion of the pigment, prevents agglomeration to maintain the mechanical properties of the matrix, and simultaneously imparts excellent surface lubrication properties to the masterbatch. 3. Modifying graphene or molybdenum disulfide nanosheets with polydopamine endows the two-dimensional material with two key properties: first, the "universal adhesion" of the polydopamine layer, which can form an extremely strong bond with the inorganic pigment core surface through various secondary bond interactions; second, the modified nanosheet surface is rich in active groups and charged, enabling dense and complete encapsulation through electrostatic self-assembly. The resulting core-shell structure not only prevents pigment agglomeration and ensures uniform and vibrant colors, but also makes each pigment particle an independent "micro-solid lubrication unit." The excellent interlayer slip properties of graphene or molybdenum disulfide are fully utilized, providing durable and stable lubrication at the friction interface, significantly reducing the dynamic friction coefficient of thermoplastic polyurethane composites and improving their wear resistance. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0032] This application discloses a core-shell structured coated pigment wear-resistant masterbatch, comprising the following raw materials in parts by weight: 50-75 parts of carrier resin, 25-50 parts of core-shell structured pigment, and 0.5-2 parts of dispersant; the core-shell structured pigment consists of an inorganic pigment core and a functional shell layer coated on the surface of the inorganic pigment core; the functional shell layer is made of modified nano-silicone resin or a polymer-modified two-dimensional layered solid lubricating material; the carrier resin is thermoplastic polyurethane.

[0033] This application discloses a method for preparing a core-shell structured coated pigment wear-resistant masterbatch, comprising the following steps: mixing a carrier resin, a core-shell structured pigment and a dispersant, stirring at 800-1200 rpm for 5-10 min, melting and extruding at 160-200℃, cooling to 20-40℃, pelletizing, and obtaining the masterbatch.

[0034] All raw materials used in the embodiments of this application are commercially available, wherein: Thermoplastic polyurethane, melt index 35g / 10min, Shenzhen Jiejiayou Plastics Co., Ltd. Maleic anhydride-grafted thermoplastic elastomer, maleic anhydride grafting rate 1.2%, Shenzhen Huixin Plastics & Chemical Co., Ltd. Rutile titanium dioxide, average particle size 0.3μm, Langfang Lanke Chemical Co., Ltd. Iron oxide red, particle size 0.4-0.7μm, Hunan Sanhuan Pigment Co., Ltd.; Molybdenum disulfide nanosheets, with an average particle size of 80 nm, produced by Ningbo Jinlei Nanomaterials Technology Co., Ltd. Graphene oxide, Chengdu JiaCai Technology Co., Ltd. Nano-silicon carbide, average particle size 40nm, Beijing Deco Island Gold Technology Co., Ltd. Boron nitride nanosheets, average particle size 200nm, Beijing Deco Island Gold Technology Co., Ltd. Tetraethyl orthosilicate, Guizhou Weidun Crystal Phosphorus Electronic Materials Co., Ltd.; Ammonia water, pH 9, Shanghai Aladdin Biochemical Technology Co., Ltd. Heptadecafluorodecyltrimethoxysilane, Hangzhou Jessica Chemical Co., Ltd.; γ-aminopropyltriethoxysilane, Hangzhou Jessica Chemical Co., Ltd.

[0035] Preparation Example 1 Preparation of core-shell structured pigments coated on the surface of inorganic pigment cores with modified nano-silicone resin: 100g of rutile titanium dioxide was mixed with a mixture of 500mL ethanol and 50mL deionized water, and ultrasonically dispersed at 500W for 20min. 5g of γ-aminopropyltriethoxysilane was added, and the mixture was heated and stirred at 60℃ for 2h. The temperature of the system was adjusted to 50℃, and 20g of tetraethyl orthosilicate and 5g of heptadecafluorodecyltrimethoxysilane were added. Then, 2mL of 25% ammonia water was added dropwise, and the mixture was stirred at 300rpm for 12h. The mixture was centrifuged at 8000rpm for 10min, washed three times with ethanol, and vacuum dried at 80℃ for 12h to obtain core-shell structured pigments coated on the surface of inorganic pigment cores with modified nano-silicone resin.

[0036] Preparation Example 2 Preparation of polydopamine-modified reduced graphene oxide: 0.1 g of graphene oxide was mixed with 200 mL of 10 mM tris(hydroxymethyl)aminomethane hydrochloride buffer at pH 8.5, and ultrasonically dispersed at 500 W for 10 min. 50 mg of dopamine hydrochloride was added, and the mixture was stirred at 60 °C for 24 h. After centrifugation at 10,000 rpm for 10 min, the mixture was washed three times with deionized water and brought to a final volume of 100 mL to obtain 1 mg / mL polydopamine-modified reduced graphene oxide.

[0037] Preparation Example 3 Preparation of core-shell structured pigments with polydopamine-modified reduced graphene oxide coating on the surface of inorganic pigment cores: 100g of iron oxide red and 400mL of deionized water were mixed and ultrasonically dispersed at 500W for 30min. The pH was adjusted to 3.0 with hydrochloric acid. 200mL of polydopamine-modified reduced graphene oxide with a concentration of 1mg / mL obtained in Preparation Example 2 was added. The mixture was magnetically stirred at 300r / min for 6h, filtered, washed with ethanol, and vacuum dried at 60℃ for 12h to obtain core-shell structured pigments with polydopamine-modified reduced graphene oxide coating on the surface of inorganic pigment cores.

[0038] Preparation Example 4 Preparation of core-shell structured pigments with polydopamine-modified molybdenum disulfide nanosheets coating the surface of inorganic pigment cores: 100g of iron oxide red and 400mL of deionized water were mixed and ultrasonically dispersed at 500W for 30min. The pH was adjusted to 3.0 with hydrochloric acid, and 200mg of molybdenum disulfide nanosheets were added. The mixture was magnetically stirred at 300r / min for 6h, filtered, washed with ethanol, and vacuum dried at 60℃ for 12h to obtain core-shell structured pigments with polydopamine-modified reduced graphene oxide coating the surface of inorganic pigment cores.

[0039] Example 1 Mix 65g of thermoplastic polyurethane, 33g of core-shell structured pigment coated on the surface of inorganic pigment core with modified nano-silicone resin obtained in Preparation Example 1, and 2g of polyethylene wax. Stir at 1000rpm for 5min, melt extrude at 180℃, cool to 25℃, and pelletize to obtain color masterbatch.

[0040] Example 2 50g of thermoplastic polyurethane, 50g of core-shell structure pigment coated with modified nano-silicone resin obtained in Preparation Example 1, and 2g of oxidized polyethylene wax were mixed, stirred at 800rpm for 10min, melt-extruded at 160℃, cooled to 20℃, and pelletized to obtain color masterbatch.

[0041] Example 3 75g of thermoplastic polyurethane, 25g of core-shell structured pigment coated on the surface of inorganic pigment core with modified nano-silicone resin obtained in Preparation Example 1, and 0.5g of polyester wax were mixed, stirred at 1200rpm for 5min, melt-extruded at 200℃, cooled to 30℃, and pelletized to obtain color masterbatch.

[0042] Example 4 The difference between this embodiment and Example 1 is that in this embodiment, the core-shell structured pigment with modified nano-silicone resin coating on the surface of inorganic pigment core in Example 1 is replaced by the core-shell structured pigment with polydopamine-modified reduced graphene oxide coating on the surface of inorganic pigment core obtained in Preparation Example 3.

[0043] Example 5 The difference between this embodiment and Example 1 is that in this embodiment, the core-shell structured pigment with modified nano-silicone resin coating on the surface of inorganic pigment core in Example 1 is replaced by the core-shell structured pigment with polydopamine-modified molybdenum disulfide nanosheets coating the surface of inorganic pigment core obtained in Preparation Example 4.

[0044] The color masterbatches obtained in Examples 1-5 were tested for coloring effect, tensile strength, elongation at break, coefficient of friction, volumetric abrasion, and Taber abrasion. Coloring effect: The coloring effect of the color masterbatches was observed visually. Tensile strength and elongation at break of the color masterbatches were tested according to ASTM D412, "Standard Test Method for Tensile Testing of Vulcanized Rubber and Thermoplastic Elastomers"; coefficient of friction and volumetric abrasion were tested according to ASTM G99, "Tribology and Wear Tests"; Taber abrasion was tested according to ASTM D4060, "Standard Test Method for Determining the Abrasion Resistance of Organic Coatings Using a Taber Abrasion Tester".

[0045] The test results of Examples 1-5 obtained according to the above test methods are shown in Table 1: Table 1 Performance testing of masterbatches in Examples 1-5

[0046] As shown in Examples 1-5 and Table 1, the color masterbatches of Examples 1-5 exhibit uniform and vibrant coloring effects, tensile strength exceeding 43.7 MPa, elongation at break exceeding 462%, coefficient of friction below 0.11, and volumetric abrasion rate below 3.8 mm. 3 The Taber wear rate is below 21 mg / 1000 r, indicating that the color masterbatch of this application has a significant coloring effect and excellent mechanical and wear resistance properties.

[0047] Comparative Example 1 The difference between this comparative example and Example 1 is that the core-shell structure pigment coated on the surface of the inorganic pigment core with modified nano-silicone resin in Example 1 is replaced by rutile titanium dioxide.

[0048] Comparative Example 2 The difference between this comparative example and Example 1 is that this comparative example uses thermoplastic polyurethane.

[0049] The masterbatches obtained in Example 1 and Comparative Examples 1-2 were tested for coloring effect, tensile strength, elongation at break, coefficient of friction, volumetric wear, and Taber wear. The test results are shown in Table 2. Table 2 Performance testing of color masterbatches in Examples 1 and 1-2

[0050] As shown in Example 1, Comparative Examples 1-2, and Table 2, the masterbatch of Example 1 exhibits uniform and vibrant coloring, a tensile strength of 44.5 MPa, an elongation at break of 475%, a coefficient of friction of 0.09, and a volumetric abrasion rate of 3.2 mm. 3 The Taber abrasion rate was 18 mg / 1000 r, which was significantly better than that of Comparative Example 1. The tensile strength and elongation at break of Example 1 were not significantly different from those of Comparative Example 2, indicating that the color masterbatch of this application can achieve nanoscale uniform dispersion and strong interfacial bonding of pigments in thermoplastic polyurethane matrix, thereby improving the mechanical properties of the color masterbatch and significantly enhancing its wear resistance while giving the product a bright and stable color.

[0051] Example 6 The difference between this embodiment and Embodiment 1 is that in this embodiment, the thermoplastic polyurethane in Embodiment 1 is replaced by maleic anhydride-grafted thermoplastic polyurethane.

[0052] Example 7 Mix 1g of nano-silicon carbide and 0.5g of boron nitride nanosheets, add 500mL of ethanol and 50mL of deionized water mixture, sonicate at 500W for 30min, add 1g of γ-aminopropyltriethoxysilane, reflux at 60℃ for 4h, centrifuge at 1000rpm for 10min, remove the supernatant, wash with ethanol to obtain composite filler; mix 65g of maleic anhydride-grafted thermoplastic polyurethane, composite filler and 1g of polyethylene wax, stir at 1000rpm for 5min, add 33g of core-shell structure pigment coated on the surface of inorganic pigment core obtained in Preparation Example 1 and 1g of polyethylene wax, stir at 1000rpm for 10min, melt extrude at 180℃, cool to 25℃, granulate to obtain masterbatch.

[0053] The masterbatches obtained in Examples 1 and 6-7 were tested for coloring effect, tensile strength, elongation at break, coefficient of friction, volumetric wear, and Taber wear. The test results are shown in Table 3. Table 3 Performance testing of masterbatches in Examples 1 and 6-7

[0054] As shown in Examples 1 and 6 and Table 3, the masterbatch of Example 6 has a tensile strength of 45.5 MPa, an elongation at break of 480%, a coefficient of friction of 0.08, and a volumetric wear rate of 2.9 mm. 3 The Taber wear was 16 mg / 1000 r, significantly better than that of Example 1. This indicates that the maleic anhydride functional groups grafted onto thermoplastic polyurethane can improve and enhance the multi-level interfacial bonding force of the "resin-shell-pigment core", thereby improving the mechanical properties and wear resistance of the polycolor masterbatch.

[0055] As shown in Examples 6-7 and Table 3, the masterbatch of Example 7 has a tensile strength of 48.2 MPa, a coefficient of friction of 0.06, and a volumetric wear rate of 2.1 mm. 3 The Taber wear was 12 mg / 1000 r, significantly better than in Example 6. This indicates that nano-silicon carbide and boron nitride nanosheets can effectively enhance the frictional properties of the system and reduce direct wear on the matrix material.

[0056] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A core-shell structure coated pigment wear resistant masterbatch, characterized in that, The raw materials include the following parts by weight: 50-75 parts of carrier resin, 25-50 parts of core-shell structured pigment, and 0.5-2 parts of dispersant; the core-shell structured pigment consists of an inorganic pigment core and a functional shell layer coated on the surface of the inorganic pigment core; the material of the functional shell layer is modified nano-silicone resin or a polymer-modified two-dimensional layered solid lubricating material; the carrier resin is thermoplastic polyurethane.

2. The abrasion resistant, core-shell structured, coated pigment masterbatch according to claim 1, wherein, The preparation steps of the modified nano-silicone resin coating inorganic pigment core surface include: mixing inorganic pigment core and solvent, ultrasonically dispersing, adding a first silane coupling agent, heating and stirring, adding tetraethyl orthosilicate and a second silane coupling agent, then adding a catalyst, stirring evenly, centrifuging, washing, and drying to obtain a core-shell structure pigment; the second silane coupling agent is a fluorinated alkyl or long-chain alkyl silane coupling agent.

3. The abrasion resistant, core-shell structured, coated pigment masterbatch according to claim 2, wherein, The first silane coupling agent is γ-aminopropyltriethoxysilane, the second silane coupling agent is heptadecafluorodecyltrimethoxysilane, the solvent is an aqueous ethanol solution, and the catalyst is ammonia.

4. The abrasion resistant, core-shell structured, coated pigment masterbatch according to claim 1, wherein, The polymer-modified two-dimensional layered solid lubricant is graphene or molybdenum disulfide nanosheets modified with polydopamine.

5. The abrasion resistant, core-shell structured, coated pigment masterbatch according to claim 4, wherein, The preparation steps of coating the inorganic pigment core surface with the polymer-modified two-dimensional layered solid lubricant material include: mixing the inorganic pigment core and solvent, ultrasonically dispersing, adjusting the pH, adding the polymer-modified two-dimensional layered solid lubricant material, stirring evenly, filtering, washing, and drying to obtain a core-shell structured pigment.

6. The abrasion resistant, core-shell structured, coated pigment masterbatch according to claim 1, wherein, The thermoplastic polyurethane is maleic anhydride-grafted thermoplastic polyurethane.

7. The core-shell structured coated pigment wear-resistant masterbatch according to claim 1, characterized in that, It also includes 1 part by weight of nano-silicon carbide and 0.5 parts by weight of boron nitride nanosheets.

8. The core-shell structured coated pigment wear-resistant masterbatch according to claim 1, characterized in that, The inorganic pigment core is at least one of rutile titanium dioxide, iron oxide red, and phthalocyanine blue; the dispersant is at least one of polyethylene wax, oxidized polyethylene wax, and polyester wax.

9. A method for preparing a core-shell structured coated pigment wear-resistant masterbatch as described in claim 1, characterized in that, Includes the following steps: The carrier resin, core-shell structured pigment, and dispersant are mixed, stirred evenly, melt-extruded, cooled, and pelletized to obtain color masterbatch.

10. The application of a core-shell structured coated pigment abrasion-resistant masterbatch according to any one of claims 1-8 in the preparation of plastic products.

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