Ultra-high molecular weight polyethylene composition, preparation method thereof, ultra-high molecular weight polyethylene product and application of ultra-high molecular weight polyethylene product

Abstract

The invention belongs to the field of high polymer materials, and particularly relates to an ultra-high molecular weight polyethylene composition, a preparation method thereof, an ultra-high molecular weight polyethylene product and application of the ultra-high molecular weight polyethylene product. The ultra-high molecular weight polyethylene composition disclosed by the invention is prepared from the following components in parts by weight: 100 parts of polyethylene, 1 to 6 parts of bulking agent, 0.5 to 3 parts of lubricating agent, 0.5 to 3 parts of flow modifier, 0.5 to 5 parts of wear-resistant filler and 0.05 to 0.5 part of coupling agent, wherein the polyethylene comprises 70-90 parts by weight of ultra-high molecular weight polyethylene and 10-30 parts by weight of polyolefin resin. The ultra-high molecular weight polyethylene composition has good melt extrusion fluidity in the processing process, and the prepared ultra-high molecular weight polyethylene product has excellent mechanical properties and wear resistance.

Description

Technical Field

[0001] The present invention belongs to the field of polymer materials, and in particular, relates to an ultra-high molecular weight polyethylene composition and a preparation method thereof, an ultra-high molecular weight polyethylene product and applications thereof. Background Art

[0002] Ultra-high molecular weight polyethylene (UHMWPE) is a thermoplastic engineering plastic with excellent comprehensive properties. In ISO11542, UHMWPE is defined as a linear polyethylene with a viscosity-average molecular weight greater than 1.5 million. The ultra-high molecular weight gives UHMWPE unparalleled high wear resistance, impact resistance, self-lubrication, low temperature resistance, chemical corrosion resistance and other properties that other plastics cannot match. As the manufacturing industry has higher and higher requirements for material properties, UHMWPE resin has a broad market prospect in the fields of textiles, papermaking, chemicals, coal, petroleum, transportation, medical care, ships, military defense, and aerospace with its excellent properties.

[0003] The high molecular weight of ultra-high molecular weight polyethylene gives it excellent performance on the one hand, and on the other hand, it also gives UHMWPE unique melt properties: the melt viscosity of UHMWPE is extremely high (>10 8 Pa·s); the melt mass flow rate (MFR) during processing is almost 0; the critical shear rate is extremely low, and when the shear rate reaches 10 -2 ·s -1 When the screw rotates, the UHMWPE may suffer from melt fracture; the low friction coefficient causes the UHMWPE melt to slip in the barrel as the screw rotates. Therefore, improving the fluidity of UHMWPE is of great significance to improving the production efficiency of UHMWPE and broadening its application.

[0004] When UHMWPE is subjected to flow modification, a large amount of low molecular weight resin and flow modifier components are added. These components are dispersed in the UHMWPE matrix and at the interface, destroying the entanglement network of UHMWPE molecular chains or forming defects with the matrix phase separation, which improves the fluidity of UHMWPE while reducing the wear resistance and mechanical properties of the product. Therefore, it is necessary to further perform wear resistance modification on the basis of flow modification to improve the performance of the product.

[0005] There are many existing patents and literature reports on methods and formulas for improving the flow and wear resistance of UHMWPE. CN104558737A discloses a method for preparing a wear-resistant ultra-high molecular weight polyethylene composition for marine use. The processing flow modifier selected is random copolymer polypropylene, and maleic anhydride grafted ethylene rubber copolymer is used as a compatibilizer. After modification, the blend is extruded by a twin screw. In this patent, polypropylene and ultra-high molecular weight polyethylene are not compatible, and there is still a certain impact on the mechanical properties and wear resistance of the product.

[0006] CN103642111A discloses an ultra-high molecular weight polyethylene antistatic and flame-retardant pipe for coal mines and a preparation method thereof. It uses linear low-density polyethylene LLDPE and chlorinated polyethylene CPE as flow modifiers, uses ACS / ABS / SMA as a compatibilizer, uses polymer wax, ethylene bisoleamide EBO, butyl stearate, octyl stearate, etc. as lubricants, and the modified blend is extruded into a pipe. The performance test of the pipe product can meet national standards.

[0007] CN104004253A discloses a high molecular weight polymer nucleating agent modified ultra-high molecular weight polyethylene blend material, which has the following components in parts by weight: 60-100 parts of UHMWPE, 5-12 parts of HDPE, 6-16 parts of LLDPE, 0.1-3 parts of high molecular weight polymer nucleating agent and 1.5-3 parts of flow modifier. The nucleating agent used for modification is dibenzylidene sorbitol and / or amide type β-crystalline nucleating agent. The obtained blend can be granulated by extrusion.

[0008] CN105001487A discloses a method for preparing a multi-purpose injection-molding grade ultra-high molecular weight polyethylene functional composition, wherein an ultra-high molecular weight polyethylene resin is first compounded with a specific proportion of a vinyl silane coupling agent, a thermal initiator, and a cross-linking catalyst, and then compounded with a low molecular weight polyolefin flow modifier to prepare an injection-molding grade ultra-high molecular weight polyethylene composition base material. The injection-molding grade ultra-high molecular weight polyethylene base material prepared by the method can also be further compounded with an antistatic agent, a nanomaterial, etc. to prepare a functional composition, but the base material needs to be mixed with a mixed liquid solvent in advance, and the production process is relatively complicated.

[0009] CN106317547A discloses an ultra-high molecular weight polyethylene composition for extrusion molding and a preparation method thereof, which comprises the following components by weight: 40-85 parts of ultra-high molecular weight polyethylene, 15-60 parts of high molecular weight polyethylene, 5-10 parts of long-chain branched polyethylene, 0.4-4 parts of processing aid, 1-3 parts of flow modifier, and 1-10 parts of wear-resistant additive. The modified composition can be processed by ordinary molding, extrusion and injection molding methods. However, the wear resistance of the product still decreases to a certain extent.

[0010] CN106117756A discloses a method for preparing injection-grade UHMWPE, which requires adding a certain amount of solvent oil to the dispersion medium, polymerizing to obtain a UHMWPE resin containing solvent oil; mixing a flow modifier, a functional additive treated with a coupling agent, an antioxidant, and an ultra-high molecular weight polyethylene resin containing solvent oil at high speed, and then extruding through a screw extruder to obtain an injection-grade ultra-high molecular weight polyethylene. This patent requires modification starting from the polymerization stage, and is not suitable for ordinary general-purpose materials, which is difficult for ordinary processing companies to achieve.

[0011] The existing melt-extruded UHMWPE flow-modified formulas are difficult to balance the two factors of processing performance and performance in use. Some flow-modified formulas require customized extrusion injection molding machines, which are difficult to promote quickly. Some formula products have a shortened product life due to performance loss.

[0012] Therefore, an ultra-high molecular weight polyethylene composition suitable for conventional extrusion injection molding processing technology is designed, which can improve the processing fluidity of UHMWPE while maintaining excellent wear-resistant mechanical properties, and has good economic benefits and industrial value. Summary of the invention

[0013] The purpose of the present invention is to overcome the technical problem of poor fluidity of UHMWPE in the prior art, and to provide an ultra-high molecular weight polyethylene composition and a preparation method thereof, an ultra-high molecular weight polyethylene composition and an application thereof. The ultra-high molecular weight polyethylene composition has good melt extrudable fluidity during processing, and the prepared ultra-high molecular weight polyethylene product has excellent mechanical properties and wear resistance.

[0014] In order to achieve the above object, the first aspect of the present invention provides an ultra-high molecular weight polyethylene composition, wherein the ultra-high molecular weight polyethylene composition comprises: 100 parts by weight of a polymer, 1-6 parts by weight of a compatibilizer, 0.5-3 parts by weight of a lubricant, 0.5-3 parts by weight of a flow modifier, 0.5-5 parts by weight of a wear-resistant filler, and 0.05-0.5 parts by weight of a coupling agent;

[0015] The polymer comprises 70-90 parts by weight of ultra-high molecular weight polyethylene and 10-30 parts by weight of polyolefin resin.

[0016] The second aspect of the present invention provides a method for preparing an ultra-high molecular weight polyethylene product, wherein the preparation method comprises mixing the above-mentioned ultra-high molecular weight polyethylene composition to obtain a mixed material, and extruding the mixed material to obtain the ultra-high molecular weight polyethylene product.

[0017] The third aspect of the present invention provides an ultra-high molecular weight polyethylene product prepared by the above method.

[0018] A fourth aspect of the present invention provides an application of the ultra-high molecular weight polyethylene product described above in at least one of extruded pipes, extruded profiles and extruded sheets.

[0019] Through the above technical scheme, the ultra-high molecular weight polyethylene composition and preparation method thereof, ultra-high molecular weight polyethylene product and application thereof provided by the present invention achieve the following beneficial effects:

[0020] The ultra-high molecular weight polyethylene composition has good melt-extrusion fluidity during processing, and the prepared ultra-high molecular weight polyethylene product has excellent mechanical properties and wear resistance. DETAILED DESCRIPTION

[0021] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0022] The first aspect of the present invention provides an ultra-high molecular weight polyethylene composition, wherein the ultra-high molecular weight polyethylene composition comprises: 100 parts by weight of a polymer, 1-6 parts by weight of a compatibilizer, 0.5-3 parts by weight of a lubricant, 0.5-3 parts by weight of a flow modifier, 0.5-5 parts by weight of a wear-resistant filler and 0.05-0.5 parts by weight of a coupling agent; wherein the polymer comprises 70-90 parts by weight of ultra-high molecular weight polyethylene and 10-30 parts by weight of a polyolefin resin.

[0023] In the present invention, the general ultra-high molecular weight polyethylene material has the problem of insufficient fluidity and difficult processing due to insufficient molecular chain disentanglement ability or uneven disentanglement. The ultra-high molecular weight polyethylene composition provided by the present invention has good melt extrusion fluidity, and the obtained ultra-high molecular weight polyethylene product maintains the excellent mechanical properties and wear resistance of ultra-high molecular weight polyethylene.

[0024] Furthermore, the ultra-high molecular weight polyethylene composition comprises: 100 parts by weight of a polymer, 3-5 parts by weight of a compatibilizer, 1-2 parts by weight of a lubricant, 1-2 parts by weight of a flow modifier, 2-4 parts by weight of a wear-resistant filler and 0.2-0.3 parts by weight of a coupling agent; wherein the polymer comprises 75-80 parts by weight of ultra-high molecular weight polyethylene and 20-25 parts by weight of a polyolefin resin.

[0025] According to the present invention, the viscosity average molecular weight of the ultra-high molecular weight polyethylene is 1.5-4.5 million.

[0026] In the present invention, when the viscosity-average molecular weight of the ultra-high molecular weight polyethylene is greater than 4.5 million, the molecular chain disentanglement ability is insufficient or the disentanglement is uneven, resulting in a decrease in the fluidity of the ultra-high molecular weight polyethylene composition; when the viscosity-average molecular weight of the ultra-high molecular weight polyethylene is less than 1.5 million, the wear resistance and mechanical properties of the ultra-high molecular weight polyethylene itself are greatly reduced; during the preparation of the product, the uneven mixing of the components of the composition will cause serious abrasive wear, resulting in poor wear resistance of the ultra-high molecular weight polyethylene product.

[0027] Furthermore, the viscosity average molecular weight of the ultra-high molecular weight polyethylene is 2-3.5 million.

[0028] According to the present invention, the ultra-high molecular weight polyethylene has a simple supported beam notched impact strength of 80-200 kJ / m 2 .

[0029] Furthermore, the ultra-high molecular weight polyethylene has a simple supported beam notched impact strength of 120-180 kJ / m 2 .

[0030] According to the present invention, at 190° C. and a load of 21.6 kg, the melt mass flow rate of the ultra-high molecular weight polyethylene composition is 0.1-5 g / 10 min.

[0031] In the present invention, the composition satisfying the above range of melt mass flow rate under the above conditions has good fluidity and can be processed to prepare an ultra-high molecular weight polyethylene product.

[0032] Furthermore, at 190° C. and a load of 21.6 kg, the melt mass flow rate of the ultra-high molecular weight polyethylene composition is 1-3 g / 10 min.

[0033] According to the present invention, at 180°C, the melt viscosity of the ultra-high molecular weight polyethylene composition is less than 10 7 Pa·s.

[0034] In the present invention, the ultra-high molecular weight polyethylene composition having a melt viscosity within the above range can flow and can be molded.

[0035] Furthermore, at 180° C., the melt viscosity of the ultra-high molecular weight polyethylene composition is 9×10 5 -10 7 Pa·s.

[0036] In the present invention, the ultra-high molecular weight polyethylene is an industrial product obtained by polymerization using at least one of a Ziegler-Natta catalyst, a metallocene catalyst or a non-transition metallocene catalyst.

[0037] According to the present invention, the weight average molecular weight of the polyolefin resin is 40,000-200,000.

[0038] In the present invention, the polyolefin resin has excellent fluidity. When used in an ultra-high molecular weight polyethylene composition, the polyolefin resin has good compatibility with the ultra-high molecular weight polyethylene and can be uniformly dispersed in the ultra-high molecular weight polyethylene.

[0039] According to the present invention, the polyolefin resin includes polyethylene and / or polypropylene.

[0040] According to the present invention, the density of the polyethylene is 0.94-0.96 g / cm 3 .

[0041] Furthermore, the density of the polyethylene is 0.945-0.955 g / cm 3 .

[0042] According to the present invention, the weight average molecular weight of the polyethylene is 50,000-300,000.

[0043] Furthermore, the weight average molecular weight of the polyethylene is 100,000-200,000.

[0044] According to the present invention, the melt viscosity of the polyethylene at 180°C is 7.6×10 3 -7×10 4 Pa·s.

[0045] In the present invention, when the melt viscosity of polyethylene meets the above range, it has good processability. 3 Pa·s, the viscosity of the ultra-high molecular weight polyethylene is mismatched during the preparation of the product, and it is difficult to mix evenly; when the selected resin melt viscosity is greater than 7×10 4 When the viscosity is less than 0.05 Pa·s, the fluidity is poor and the composition is difficult to process.

[0046] Furthermore, the melt viscosity of the polyethylene at 180°C is 10 4 -5×10 4 Pa·s.

[0047] According to the present invention, the melt mass flow rate of the polyethylene at 190° C. and a load of 2.16 kg is 0.1-10 g / 10 min.

[0048] Furthermore, the polyethylene has a melt mass flow rate of 1-5 g / 10 min at 190° C. and a load of 2.16 kg.

[0049] According to the present invention, the density of the polypropylene is 0.895-0.91 g / cm 3 .

[0050] Furthermore, the density of the polypropylene is 0.90-0.91 g / cm 3 .

[0051] According to the present invention, the weight average molecular weight of the polypropylene is 400,000-800,000.

[0052] Furthermore, the weight average molecular weight of the polypropylene is 500,000-700,000.

[0053] According to the present invention, the melt viscosity of the polypropylene at 180°C is 5.8×10 4 -8×10 5 Pa·s.

[0054] In the present invention, when the melt viscosity of polypropylene meets the above range, the processing performance is excellent. 4 Pa·s, it is difficult to mix evenly with ultra-high molecular weight polyethylene during the preparation of products, and the compatibility is poor; when the selected resin melt viscosity is greater than 8×10 5 When the viscosity is less than 0.05 Pa·s, the fluidity is poor and the composition is difficult to process.

[0055] Furthermore, the melt viscosity of the polypropylene at 180°C is 2×10 5 -6×10 5 Pa·s.

[0056] According to the present invention, the melt mass flow rate of the polypropylene at 230° C. and a load of 2.16 kg is 0.1-10 g / 10 min.

[0057] Furthermore, the melt mass flow rate of the polypropylene at 230° C. and a load of 2.16 kg is 0.2-5 g / 10 min.

[0058] According to the present invention, the polyolefin resin is polyethylene and polypropylene, and the weight ratio of the polyethylene to the polypropylene is 1:0.1-5.

[0059] In the present invention, when the polyethylene and the polypropylene simultaneously meet the above ranges, the ultra-high molecular weight polyethylene and the polyolefin resin can be mixed more fully and have good fluidity, which is beneficial to improving the molding processability of the composition.

[0060] Furthermore, the polyolefin resin is polyethylene and polypropylene, and the weight ratio of the polyethylene to the polypropylene is 1:0.3-3.

[0061] According to the present invention, the compatibilizer is selected from at least one of EPDM rubber, polyolefin elastomer (POE) and olefin block copolymer elastomer.

[0062] Furthermore, the compatibilizer is an olefin block copolymer elastomer (OBC).

[0063] According to the present invention, the lubricant is selected from at least one of stearic acid, stearate, oleamide, polyethylene wax, methyl silsesquioxane and organic-inorganic hybrid flow modifier.

[0064] Furthermore, the stearate is calcium stearate and / or zinc stearate.

[0065] Furthermore, the organic-inorganic hybrid flow modifier is a polymer-nanoclay complex and / or a polymer-cage-like semi-siloxane nanomaterial (POSS).

[0066] Furthermore, the lubricant is a compound of stearate and an organic-inorganic hybrid flow improver, and the weight ratio of the stearate to the organic-inorganic hybrid flow improver is 1:0.1-1.

[0067] Furthermore, the lubricant is a compound of stearate and an organic-inorganic hybrid flow improver, and the weight ratio of the stearate to the organic-inorganic hybrid flow improver is 1:0.3-0.8.

[0068] For example, the structural formula of polymer-cage-like semi-siloxane nanomaterials is (RSiO 1.5 ) n , further, the chemical structure is shown in Figure (I):

[0069]

[0070] The R group can be methyl, isobutyl, octyl, vinyl, octene, dodecyl, amino, phenyl, hydroxyl, acrylic, trimethylsilyl, glycidyl dimethylsilyl, acryloxypropyl, methacryloxy, or epoxycyclohexylethyl.

[0071] Furthermore, the R group is a methyl group or a vinyl group.

[0072] According to the present invention, the flow modifier is selected from at least one of fluoroolefin polymers, silicone powder and nano silicon dioxide.

[0073] Furthermore, the flow improver is selected from a copolymer obtained by polymerizing at least two monomers of vinylidene fluoride, tetrafluoroethylene and hexafluoropropylene.

[0074] Furthermore, the flow improver is selected from a homopolymer obtained by polymerizing any one monomer of vinylidene fluoride, tetrafluoroethylene and hexafluoropropylene.

[0075] Furthermore, the flow improver is selected from polyvinylidene fluoride-hexafluoropropylene copolymer and / or tetrafluoroethylene homopolymer.

[0076] According to the present invention, the particle size of the nano-silicon dioxide is 1-50 nm.

[0077] The inventors found in the course of their research that the nano-silicon dioxide with a specific particle size selected as the flow modifier can improve the fluidity of the composition while maintaining excellent physical properties of the final product.

[0078] Furthermore, the particle size of the nano-silicon dioxide is 5-30nm.

[0079] According to the present invention, the wear-resistant filler comprises a wear-resistant additive and a compound lubricant.

[0080] Furthermore, the wear-resistant additive is selected from at least one of silicon dioxide, aluminum oxide, zinc oxide, silicon nitride, silicon carbide and calcium carbonate.

[0081] According to the present invention, the particle size of the wear-resistant additive is 100-200 μm.

[0082] According to the present invention, the compound lubricant is selected from molybdenum disulfide and / or graphene.

[0083] According to the present invention, in the wear-resistant filler, the weight ratio of the wear-resistant additive to the compound lubricant is 5-10:1.

[0084] In the present invention, when the wear-resistant additive and the compound lubricant meet the above weight ratio range, the ultra-high molecular weight polyethylene composition can have good fluidity, and the obtained ultra-high molecular weight polyethylene can have good wear resistance.

[0085] Furthermore, in the wear-resistant filler, the weight ratio of the wear-resistant additive to the compound lubricant is 8-10:1.

[0086] According to the present invention, the coupling agent is selected from at least one of a titanate coupling agent, a silane coupling agent, an aluminate coupling agent and an aluminum titanate coupling agent.

[0087] The second aspect of the present invention provides a method for preparing an ultra-high molecular weight polyethylene product, wherein the preparation method comprises mixing the components in any one of the ultra-high molecular weight polyethylene compositions described above to obtain a mixed material, and extruding the mixed material to obtain the ultra-high molecular weight polyethylene product.

[0088] According to the present invention, the mixing is carried out according to the following steps:

[0089] (a) first mixing ultra-high molecular weight polyethylene, polyolefin resin, lubricant, flow modifier, and compatibilizer to obtain an ultra-high molecular weight polyethylene high-flow mixture;

[0090] (b) performing a second mixing of the wear-resistant filler, the coupling agent and the ultra-high molecular weight polyethylene high-flowable mixture to obtain a mixed material.

[0091] In the present invention, the first mixing and the second mixing are performed in a mixer.

[0092] According to the present invention, in step (a), the first mixing conditions include: a rotation speed of 500-2000 r / min; and a time of 2-5 min.

[0093] According to the present invention, in step (b), the second mixing conditions include: a rotation speed of 200-1000 r / min; and a time of 2-10 min.

[0094] According to the present invention, the extrusion molding conditions include: a temperature of 160-260° C. and a rotation speed of 20-100 rpm.

[0095] Furthermore, the extrusion molding conditions include: a temperature of 180-240° C. and a rotation speed of 40-60 rpm.

[0096] According to the present invention, at 190° C. and a load of 21.6 kg, the melt mass flow rate of the ultra-high molecular weight polyethylene composition is 0.1-5 g / 10 min.

[0097] In the present invention, the composition satisfying the above range of melt mass flow rate under the above conditions has good fluidity and can be processed to prepare an ultra-high molecular weight polyethylene product.

[0098] Furthermore, the melt mass flow rate of the ultra-high molecular weight polyethylene composition is 1-3 g / 10 min.

[0099] According to the present invention, at 180°C, the melt viscosity of the ultra-high molecular weight polyethylene composition is less than 10 7 Pa·s.

[0100] In the present invention, the ultra-high molecular weight polyethylene composition having a melt viscosity within the above range can flow and can be molded.

[0101] Furthermore, at 180° C., the melt viscosity of the ultra-high molecular weight polyethylene composition is 9×10 5 -10 7 Pa·s.

[0102] The third aspect of the present invention provides an ultra-high molecular weight polyethylene product prepared by the above method.

[0103] According to the present invention, the wear index of the modified ultra-high molecular weight polyethylene product is ≤120%.

[0104] Furthermore, the wear index of the modified ultra-high molecular weight polyethylene product is ≤110%.

[0105] A fourth aspect of the present invention provides an application of the ultra-high molecular weight polyethylene product described above in at least one of extruded pipes, extruded profiles and extruded sheets.

[0106] The present invention will be described in detail below through examples.

[0107] (1) Melt flow rate (MFR): The test was conducted according to the method described in GB / T 3682.1-2018: the test conditions for polyethylene were 190°C and 2.16 kg load, the test conditions for polypropylene were 230°C and 2.16 kg load, and the test conditions for modified ultra-high molecular weight polyethylene products were 190°C and 21.6 kg load.

[0108] (2) Tensile stress at break and tensile strain at break: tested according to the method described in GB / T 1040.2-2022.

[0109] (3) Simply supported beam notched impact strength: tested according to the method described in GB / T 1043-2008.

[0110] (4) Wear index: This is carried out in accordance with the requirements of Appendix B of ISO 15527:2010. The reference sample is Ticona GUR4012.

[0111] (5) The melt viscosity was tested using a rotational rheometer. The specific test steps were as follows: the sample was made into a disc with a thickness of 1 mm and a diameter of 8 mm, and a dynamic frequency scan was performed at 180°C with a constant strain of 0.5% and a frequency scan range of 100-0.01 rad / s. The complex viscosity curve of the sample was obtained, and the complex viscosity of the sample at 0.01 rad / s was selected as its melt viscosity.

[0112] The raw materials used in the following examples and comparative examples are as follows:

[0113] Ultra-high molecular weight polyethylene UHMWPE-1: brand X-3004F, purchased from Sinopec Yanshan Petrochemical Company, viscosity average molecular weight 3 million, simple supported beam notched impact strength 150kJ / m 2 ;

[0114] Ultra-high molecular weight polyethylene UHMWPE-2: brand GK01, purchased from Sinopec Yanshan Petrochemical Company, viscosity average molecular weight 1.3 million, simple supported beam notched impact strength 200kJ / m 2 ;

[0115] Polyethylene PE-1: 5000S, purchased from Sinopec Yanshan Petrochemical Company, at 190°C, 2.16kg load, melt mass flow rate is 1g / 10min, density is 0.95g / cm 3 , the melt viscosity is 3.6×10 4 Pa·s;

[0116] Polyethylene PE-2: 1620J, purchased from Sinopec Yanshan Petrochemical Company, at 190°C, 2.16kg load, melt mass flow rate is 20g / 10min, density is 0.956g / cm 3 , the melt viscosity is 7.6×10 3 Pa·s;

[0117] Polypropylene PP-1: B6101, purchased from Sinopec Yanshan Petrochemical Company, at 230°C, 2.16kg load, melt mass flow rate is 0.4g / 10min, density is 0.905g / cm 3 , the melt viscosity is 4.2×10 5 Pa·s;

[0118] Polypropylene PP-2: K9829H, purchased from Sinopec Yanshan Petrochemical Company, at 230°C, 2.16kg load, melt mass flow rate is 30g / 10min, density is 0.9g / cm 3 , the melt viscosity is 5.8×10 4 Pa·s;

[0119] Polyolefin elastomer POE-1: 6102, purchased from Exxon Mobil, at 190°C, 2.16 kg load, melt mass flow rate is 1.4 g / 10 min, density is 0.862 g / cm 3 ;

[0120] Olefin block copolymer elastomer OBC-1:9500, purchased from DOW Chemical, at 190°C, 2.16 kg load, melt mass flow rate of 5 g / 10 min, density of 0.877 g / cm 3 ;

[0121] Flow modifier: nanosilica A, particle size 20 nm;

[0122] Flow modifier: nanosilica B, particle size 40 nm;

[0123] Flow modifier: nano-silica C, particle size 100 nm;

[0124] Other raw materials used in the examples and comparative examples are all commercially available.

[0125] Example 1 (A1)

[0126] (a) first mixing ultra-high molecular weight polyethylene, polyolefin resin, lubricant, flow modifier, and compatibilizer to obtain an ultra-high molecular weight polyethylene high flow mixture, wherein the first mixing conditions include: a rotation speed of 800 r / min; and a time of 3 min;

[0127] (b) performing a second mixing of the wear-resistant filler, the coupling agent and the ultra-high molecular weight polyethylene high flow mixture to obtain a mixed material, wherein the conditions of the second mixing include: a rotation speed of 500 r / min; and a time of 8 min;

[0128] (c) The temperatures of the heating sections of the extruder are 180° C., 230° C., 250° C., 220° C., and 220° C., respectively; the die temperature is 210° C.; and the screw speed is 40 rpm. The mixed material is extruded to obtain product A1.

[0129] The types and amounts of each material are shown in Table 1. The performance of the tested product is shown in Table 2.

[0130] Embodiment 2-7 (A2-A7)

[0131] A2-A7 were prepared according to the method of Example 1, except that the types and amounts of each material were different from those in Example 1, as shown in Table 1.

[0132] Table 1

[0133]

[0134]

[0135] Embodiment 8 (A8)

[0136] An ultra-high molecular weight polyethylene product was prepared in the same manner as in Example 1, except that the ultra-high molecular weight polyethylene was UHMWPE-2.

[0137] Embodiment 9 (A9)

[0138] The composition was prepared using the same proportion as in Example 1 to prepare an ultra-high molecular weight polyethylene product, except that the polyolefin resins were 10 parts by weight of PE-2 and 10 parts by weight of PP-2.

[0139] Example 10 (A10)

[0140] The composition is prepared in the same proportion as in Example 1 to prepare an ultra-high molecular weight polyethylene product, except that the polyvinylidene fluoride-hexafluoropropylene copolymer is replaced by nano-silicon dioxide B.

[0141] Example 11 (A11)

[0142] The composition is used in the same proportion as in Example 10 to prepare an ultra-high molecular weight polyethylene product, except that nano-silicon dioxide B is replaced by nano-silicon dioxide C.

[0143] Example 12 (A12)

[0144] The composition is of the same type and proportion as in Example 1 to prepare an ultra-high molecular weight polyethylene product, except that the preparation method is: all the raw materials are added to a high-speed mixer at the same time for mixing at a speed of 800 rpm for 10 min, the prepared mixture is added to an extruder, the temperatures of each heating section are set to 220°C, 260°C, 260°C, 260°C, and 250°C, the die temperature is set to 230°C, and the speed is 70 rpm.

[0145] Comparative Example 1 (D1)

[0146] The composition is of the same type as in Example 1 to prepare an ultra-high molecular weight polyethylene product, except that, in 100 parts by weight of the polymer, 60 parts by weight of ultra-high molecular weight polyethylene is used; and 40 parts by weight of polyolefin resin is used, including 20 parts by weight of polyethylene and 20 parts by weight of polypropylene.

[0147] Comparative Example 2 (D2)

[0148] The composition was prepared using the same type and ratio as in Example 1, except that no flow modifier was added.

[0149] Comparative Example 3 (D3)

[0150] The composition is of the same type as in Example 1 to prepare an ultra-high molecular weight polyethylene product, except that the ultra-high molecular weight polyethylene composition contains: 5 parts by weight of lubricant, 5 parts by weight of flow modifier, 10 parts by weight of wear-resistant filler, and 5 parts by weight of coupling agent.

[0151] Comparative Example 4 (D4)

[0152] An ultra-high molecular weight polyethylene product was prepared according to the method of Example 1, except that the weight ratio of silicon carbide to molybdenum disulfide was 12:1, and the total amount of wear-resistant filler was 10 parts by weight.

[0153] The performance of the ultra-high molecular weight polyethylene composition and the ultra-high molecular weight polyethylene product were tested. The performance parameters of the ultra-high molecular weight polyethylene composition are shown in Table 2, and the performance parameters of the ultra-high molecular weight polyethylene product are shown in Table 3.

[0154] Table 2

[0155]

[0156]

[0157] Table 3

[0158]

[0159] It can be seen from Table 2 that, relative to Example 1, the amount of ultra-high molecular weight polyethylene and the amount of polyolefin resin were adjusted in Comparative Example 1, and the mechanical properties and wear resistance of the product prepared in Example 1 were better; relative to Example 1, no flow modifier was added in Comparative Example 2, and the melt mass flow rate of the ultra-high molecular weight polyethylene composition was 0, indicating that it had no fluidity and could not be processed into products; relative to Example 1, the amount of lubricant, flow modifier, wear-resistant filler and coupling agent was adjusted in Comparative Example 3, and the fluidity of the final composition was improved, but the mechanical properties and wear resistance of the product were greatly reduced; relative to Example 1, the proportion and amount of wear-resistant filler were adjusted in Comparative Example 4, and it can be seen from Table 3 that the mechanical properties and wear resistance of the product in Example 1 are better.

[0160] The components of the ultra-high molecular weight polyethylene composition of the present invention act synergistically, so that the composition has good melt-extrudable fluidity, and the ultra-high molecular weight polyethylene product prepared from the composition has excellent mechanical properties and wear resistance.

[0161] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. An ultra-high molecular weight polyethylene composition, characterized in that The ultra-high molecular weight polyethylene composition comprises: 100 parts by weight of a polymer, 1-6 parts by weight of a compatibilizer, 0.5-3 parts by weight of a lubricant, 0.5-3 parts by weight of a flow modifier, 0.5-5 parts by weight of a wear-resistant filler and 0.05-0.5 parts by weight of a coupling agent; The polymer comprises 70-90 parts by weight of ultra-high molecular weight polyethylene and 10-30 parts by weight of polyolefin resin.

2. The ultra-high molecular weight polyethylene composition according to claim 1, wherein The ultra-high molecular weight polyethylene composition comprises: 100 parts by weight of a polymer, 3-5 parts by weight of a compatibilizer, 1-2 parts by weight of a lubricant, 1-2 parts by weight of a flow modifier, 2-4 parts by weight of a wear-resistant filler and 0.2-0.3 parts by weight of a coupling agent; The polymer comprises 75-80 parts by weight of ultra-high molecular weight polyethylene and 20-25 parts by weight of polyolefin resin.

3. The ultra-high molecular weight polyethylene composition according to claim 1 or 2, wherein The viscosity average molecular weight of the ultra-high molecular weight polyethylene is 1.5-4.5 million, preferably 2-3.5 million; Preferably, the ultra-high molecular weight polyethylene has a simple supported beam notched impact strength of 80-200 kJ / m 2 , preferably 120-180 kJ / m 2 ; Preferably, at 190° C. and 21.6 kg load, the melt mass flow rate of the ultra-high molecular weight polyethylene composition is 0.1-5 g / 10 min, preferably 1-3 g / 10 min; Preferably, at 180°C, the melt viscosity of the ultra-high molecular weight polyethylene composition is less than 10 7 Pa·s, preferably 9×10 5 -10 7 Pa·s.

4. The ultra-high molecular weight polyethylene composition according to any one of claims 1 to 3; wherein The polyolefin resin includes polyethylene and / or polypropylene; Preferably, the density of the polyethylene is 0.94-0.96 g / cm 3 , preferably 0.945-0.955 g / cm 3 ; Preferably, the weight average molecular weight of the polyethylene is 50,000-300,000, preferably 100,000-200,000; Preferably, the melt viscosity of the polyethylene at 180°C is 7.6×10 3 -7×10 4 Pa·s, preferably 10 4 -5×10 4 Pa·s; Preferably, the polyethylene has a melt mass flow rate of 0.1-10 g / 10 min, preferably 1-5 g / 10 min, at 190° C. and a load of 2.16 kg; Preferably, the density of the polypropylene is 0.895-0.91 g / cm 3 , preferably 0.90-0.91 g / cm 3 ; Preferably, the weight average molecular weight of the polypropylene is 400,000-800,000, preferably 500,000-700,000; Preferably, the melt viscosity of the polypropylene at 180°C is 5.8×10 4 -8×10 5 Pa·s, preferably 2×10 5 -6×10 5 Pa·s; Preferably, the melt mass flow rate of the polypropylene at 230° C. and 2.16 kg load is 0.1-10 g / 10 min, preferably 0.2-5 g / 10 min; Preferably, the polyolefin resin is polyethylene and polypropylene, and the weight ratio of the polyethylene to the polypropylene is 1:0.1-5, preferably 1:0.3-3.

5. The ultra-high molecular weight polyethylene composition according to any one of claims 1 to 4, wherein The compatibilizer is selected from at least one of EPDM rubber, polyolefin elastomer and olefin block copolymer elastomer; Preferably, the compatibilizer is an olefin block copolymer elastomer.

6. The ultra-high molecular weight polyethylene composition according to any one of claims 1 to 5, wherein The lubricant is selected from at least one of stearic acid, stearate, oleamide, polyethylene wax, methyl silsesquioxane and organic-inorganic hybrid flow modifier; Preferably, the stearate is calcium stearate and / or zinc stearate; Preferably, the organic-inorganic hybrid flow modifier is a polymer-nanoclay complex and / or a polymer-cage-like semisiloxane nanomaterial; Preferably, the lubricant is a compound of stearate and an organic-inorganic hybrid flow improver, wherein the weight ratio of the stearate to the organic-inorganic hybrid flow improver is 1:0.1-1, preferably 1:0.3-0.

8.

7. The ultra-high molecular weight polyethylene composition according to any one of claims 1 to 6, wherein The flow modifier is selected from at least one of fluoroolefin polymers, silicone powder and nano silicon dioxide; Preferably, the flow modifier is selected from a copolymer obtained by polymerizing at least two monomers of vinylidene fluoride, tetrafluoroethylene and hexafluoropropylene; Preferably, the flow modifier is selected from a homopolymer obtained by polymerizing any one of vinylidene fluoride, tetrafluoroethylene and hexafluoropropylene; Preferably, the flow modifier is selected from polyvinylidene fluoride-hexafluoropropylene copolymer and / or tetrafluoroethylene homopolymer; Preferably, the particle size of the nano-silicon dioxide is 1-50 nm, preferably 5-30 nm.

8. The ultra-high molecular weight polyethylene composition according to any one of claims 1 to 7, wherein The wear-resistant filler comprises a wear-resistant additive and a compound lubricant; Preferably, the wear-resistant additive is selected from at least one of silicon dioxide, aluminum oxide, zinc oxide, silicon nitride, silicon carbide and calcium carbonate; Preferably, the particle size of the wear-resistant additive is 100-200 μm; Preferably, the compound lubricant is selected from molybdenum disulfide and / or graphene; Preferably, in the wear-resistant filler, the weight ratio of the wear-resistant additive to the compound lubricant is 5-10:1, preferably 8-10:

1.

9. The ultra-high molecular weight polyethylene composition according to any one of claims 1 to 8, wherein The coupling agent is selected from at least one of a titanate coupling agent, a silane coupling agent, an aluminate coupling agent and an aluminum titanate coupling agent.

10. A method for preparing an ultra-high molecular weight polyethylene product, characterized in that: The preparation method comprises mixing the components in the ultra-high molecular weight polyethylene composition according to any one of claims 1 to 9 to obtain a mixed material, and extruding the mixed material to obtain the ultra-high molecular weight polyethylene product.

11. The preparation method according to claim 10, wherein: The mixing is carried out according to the following steps: (a) first mixing ultra-high molecular weight polyethylene, polyolefin resin, lubricant, flow modifier, and compatibilizer to obtain an ultra-high molecular weight polyethylene high-flow mixture; (b) performing a second mixing of the wear-resistant filler, the coupling agent and the ultra-high molecular weight polyethylene high-flowable mixture to obtain a mixed material.

12. The preparation method according to claim 11, wherein In step (a), the first mixing conditions include: a rotation speed of 500-2000 r / min and a time of 2-5 min; Preferably, in step (b), the second mixing conditions include: a rotation speed of 200-1000 r / min and a time of 2-10 min.

13. The preparation method according to any one of claims 10 to 12, wherein the extrusion molding conditions include: The temperature is 160-260°C and the speed is 20-100rpm; Preferably, the extrusion molding conditions include: temperature of 180-240°C, rotation speed of 40-60rpm; Preferably, at 190° C. and 21.6 kg load, the melt mass flow rate of the ultra-high molecular weight polyethylene composition is 0.1-5 g / 10 min, preferably 1-3 g / 10 min; Preferably, at 180°C, the melt viscosity of the ultra-high molecular weight polyethylene composition is less than 10 7 Pa·s, preferably 9×10 5 -10 7 Pa·s.

14. An ultra-high molecular weight polyethylene product prepared by the preparation method according to any one of claims 10 to 13; Preferably, the wear index of the ultra-high molecular weight polyethylene product is ≤120%, preferably ≤110%.

15. Use of the ultra-high molecular weight polyethylene product according to claim 14 in at least one of extruded pipes, extruded profiles and extruded sheets.

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