Rubber material with characteristic of high wear resistance and capable of being used for pneumatic element

Abstract

The invention belongs to the technical field of synthetic rubber, and particularly relates to a rubber material which has the characteristic of high wear resistance and can be used for pneumatic elements. The rubber material comprises the following raw material components: graft modified molybdenum disulfide and graft modified polytetrafluoroethylene micro powder, and the graft modified molybdenum disulfide and the graft modified polytetrafluoroethylene micro powder are prepared by the following plasma-grafting method: S1, plasma pretreatment; s2, chemical grafting treatment; and S3, post-processing. The rubber material at least has the beneficial effects that products such as air cylinder sealing rings and air pump diaphragms prepared from the rubber material have sufficient mechanical properties and outstanding wear resistance, and the specific level of the latter is that the air tightness (frequency) of the latter is at least 15,000,000 times during motion fatigue wear, and the air tightness is far higher than the existing qualified standard of the nitrile rubber industry.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of synthetic rubber, and particularly relates to a rubber material with high wear resistance and used for pneumatic components. BACKGROUND

[0002] Common pneumatic rubber components include sealing rings of air cylinders, diaphragm sheets of air pumps, and sealing gaskets of pneumatic valves.

[0003] Taking the sealing ring of the air cylinder as an example, the sealing ring will be frequently rubbed against the inner wall of the cylinder or the cylinder shaft during normal use. Therefore, the rubber material used for the sealing ring of the air cylinder must have outstanding wear resistance. Generally, the qualified standard of the wear resistance is that the number of times of motion fatigue wear without air leakage is greater than or equal to 10 million times.

[0004] The test method of the qualified standard is an accelerated life test method simulating the actual working condition. In the test method, the sealing ring can be correctly installed in the corresponding sealing ring groove of the actual air cylinder product, and the simulation test (for example, 50 times / min) can be performed in a manner obviously higher than the actual frequency, the parameters such as pressure and temperature are all simulated in the actual working condition, then the air tightness of the sealing ring is detected at each time node of 10 million times, and finally the specific number of times of motion fatigue wear of the test sample is obtained.

[0005] The test method can refer to the following standards: ASTM D2229 Standard Test Method for Dynamic Friction and Wear Between Rubber and Rigid Materials; ISO 4649 Determination of the Amount of Wear of Rubber Under Abrasion; and ISO 7238 Determination of the Compression Set of Rubber Products.

[0006] The rubber material used for the sealing ring of the air cylinder is generally nitrile rubber, which has relatively outstanding and comprehensive wear resistance, oil resistance, heat resistance, and chemical stability.

[0007] For example, the patent application with the application publication number CN108641151A and the application publication date October 12, 2018 discloses a high-wear-resistance low-temperature-resistant and hydraulic oil-resistant hydrogenated nitrile rubber compound, the raw material composition of which includes the following components by weight: 100 parts of hydrogenated nitrile rubber, 6-10 parts of inorganic active agent, 3-5 parts of organic active agent, 1-3 parts of antioxidant, 1-3 parts of paraffin, 40-60 parts of super wear-resistant reinforcing material, 20-40 parts of wear-resistant agent, 10-20 parts of wear-resistant agent aid A, 5-10 parts of wear-resistant agent aid B, 3-6 parts of wear-resistant agent aid C, 5-20 parts of low-temperature-resistant plasticizer, 4-8 parts of vulcanizing agent, and 3-6 parts of vulcanizing aid.

[0008] The hydrogenated nitrile rubber compound in the patent application has the advantages of excellent sealing effect and long service life.

[0009] However, when the hydrogenated nitrile rubber material is actually used in the position of the cylinder sealing ring and the like, at least the following problem of insufficient wear resistance exists: the wear resistance corresponding to the door closer rotation wear test of ≥100 million times is still relatively low, and is basically flat with the above-mentioned qualified standard of 1000 million times, without obvious improvement. SUMMARY

[0010] The present application provides a rubber material with high wear resistance characteristics for pneumatic components, which solves the technical problem of how to significantly improve the wear resistance of pneumatic rubber components.

[0011] The technical solution adopted by the present application to solve the above problems is: a rubber material with high wear resistance characteristics for pneumatic components, the raw material composition includes the following components: grafted modified molybdenum disulfide and grafted modified polytetrafluoroethylene micro powder, the grafted modified molybdenum disulfide and the grafted modified polytetrafluoroethylene micro powder are prepared together by the following plasma-grafting method,

[0012] S1, plasma pretreatment: using a radio frequency plasma generator or a microwave plasma generator, the molybdenum disulfide and the polytetrafluoroethylene micro powder are treated together in an oxygen atmosphere to obtain an intermediate powder;

[0013] S2, chemical grafting treatment: the intermediate powder is prepared into a mixed solution, peroxide initiator and methacrylic acid grafting monomer are added to the mixed solution, and then heating grafting operation is carried out to obtain a grafted material;

[0014] S3, post-treatment: the grafted material is sequentially subjected to filtration, washing and drying operations to obtain a mixed grafted material composed of the grafted modified molybdenum disulfide and the grafted modified polytetrafluoroethylene micro powder.

[0015] In the prior art, molybdenum disulfide and polytetrafluoroethylene micro powder have been used in the formula of nitrile rubber, and the common characteristics and functions of the two mainly include: as a solid lubricant, it can reduce the friction coefficient of nitrile rubber and improve the wear resistance of nitrile rubber.

[0016] Even though both are solid lubricants, molybdenum disulfide and polytetrafluoroethylene micro powder have clear differences, i.e., molybdenum disulfide has more outstanding wear resistance and drag reduction performance, while polytetrafluoroethylene micro powder also has the advantage of improving chemical corrosion resistance. Therefore, molybdenum disulfide and polytetrafluoroethylene micro powder are generally used together.

[0017] In addition, and most importantly, the applicant found that if molybdenum disulfide and polytetrafluoroethylene micro powder are both directly added, at least the following problems will exist:

[0018] For molybdenum disulfide, it may have the harmful problem of uneven dispersion in the raw material system of butyl rubber, leading to inconsistent performance of local areas of rubber and affecting the overall wear resistance and drag reduction performance.

[0019] For polytetrafluoroethylene powder, it also has the risk of uneven dispersion as described above, and it also has the problem of harmful gas release during processing due to high environmental temperature, including perfluoroisobutylene (PFIB), hydrogen fluoride (HF), and carbon monoxide (CO). This is the reason why molybdenum disulfide and polytetrafluoroethylene powder need to be grafted in this application.

[0020] Correspondingly, the main advantage of the grafted molybdenum disulfide compared to ordinary, directly purchased molybdenum disulfide is good dispersion. The main advantage of the grafted polytetrafluoroethylene powder compared to ordinary, directly purchased polytetrafluoroethylene powder is good dispersion. At the same time, it is not easy to release harmful gases.

[0021] The reason is that:

[0022] First, the grafting group improves the surface defects of molybdenum disulfide and polytetrafluoroethylene powder, improves the uniformity of particle size, compatibility, and self-lubricating performance;

[0023] Second, the plasma pretreatment method removes and repairs the above-mentioned surface defects in advance, generates more free radicals, and makes the subsequent grafting treatment have faster speed and higher success rate.

[0024] Further preferred technical solutions are that in S1, the weight ratio of the molybdenum disulfide and the polytetrafluoroethylene powder is 1: (1.2-1.5), the particle size of the molybdenum disulfide is 4.0-10.5 μm, and the polytetrafluoroethylene powder is 3.0-4.0 μm.

[0025] Further preferred technical solutions are that in S1, the gas flow of the radio frequency plasma generator or microwave plasma generator is 50-100 sccm, the power is 200-500 W, and the pretreatment time is 15-25 min.

[0026] Further preferred technical solutions are that in S2, the solvent of the mixed solution is any one of water, ethanol, toluene, methyl ethyl ketone, and ethyl acetate, and the temperature of the heating grafting operation is 75-110°C.

[0027] The further preferred technical solution is characterized in that the raw material composition comprises the following components by weight: 100 parts of nitrile rubber, 3.5-4.5 parts of vulcanizing agent, 5-6 parts of zinc oxide, 0.5-1.5 parts of stearic acid, 60-70 parts of carbon black, 10-15 parts of white carbon black, 2.5-3.5 parts of antioxidant, 7-10 parts of viscosity modifier, and 5-11 parts of the mixed grafting material.

[0028] The further preferred technical solution is characterized in that the raw material composition comprises the following components by weight: 100 parts of nitrile rubber, 3.5-4.5 parts of vulcanizing agent, 5-6 parts of zinc oxide, 0.5-1.5 parts of stearic acid, 60-70 parts of carbon black, 10-15 parts of white carbon black, 2.5-3.5 parts of antioxidant, 7-10 parts of viscosity modifier, and 5-11 parts of the mixed grafting material.

[0029] The further preferred technical solution is characterized in that the nitrile content of the nitrile rubber is 30-35 wt%.

[0030] The further preferred technical solution is characterized in that the vulcanizing agent is any one or mixture of several of sulfur, dicumyl peroxide, benzoyl peroxide, phenolic resin, and benzophenone dioxime.

[0031] The further preferred technical solution is characterized in that the antioxidant is a mixture of antioxidant RD and antioxidant BLE, and the viscosity modifier is a mixture of phthalate, paraffin oil, white oil, and polyethylene glycol.

[0032] The further preferred technical solution is characterized in that the production method comprises the following steps in sequence:

[0033] T1, the nitrile rubber, carbon black, white carbon black, and mixed grafting material are put into a banbury mixer, uniformly plasticated, then the antioxidant and viscosity modifier are added, uniformly mixed, discharged, and cooled to obtain a masterbatch;

[0034] T2, the masterbatch is put into an open mill, the vulcanizing agent, zinc oxide, and stearic acid are added, uniformly mixed, discharged, and cooled to obtain a final batch;

[0035] T3, the final batch is put into a mold of a vulcanizing machine, vulcanized, cooled to room temperature after vulcanization, and demolded to obtain the rubber material with high wear resistance characteristics for pneumatic components.

[0036] The beneficial effects of the present application include at least the following three points.

[0037] First, the rubber material produces products such as cylinder sealing rings and air pump diaphragm sheets, which have sufficient mechanical properties and outstanding wear resistance. The specific level of the latter is that the motion fatigue wear does not leak gas (times) at least 15 million times, which is much higher than the existing qualified standard of nitrile rubber industry.

[0038] Secondly, the mixed grafting material has the dual advantages of good dispersion uniformity and the difficulty of generating harmful gases from polytetrafluoroethylene fine powder, thereby further improving the wear resistance and drag reduction performance.

[0039] Thirdly, the plasma-grafting method and the production method of the rubber material itself have the advantages of relatively low process condition requirements and overall safe and efficient operation mode. DETAILED DESCRIPTION

[0040] The following description is only a preferred embodiment of the present application, and does not limit the scope of the present application.

[0041] Example 1

[0042] A rubber material with high wear resistance for pneumatic components, the raw material composition includes the following components by weight: 100 parts of nitrile rubber, 4.0 parts of vulcanizing agent, 6 parts of zinc oxide, 0.5 parts of stearic acid, 62 parts of carbon black, 14 parts of white carbon black, 3.5 parts of antioxidant, 9 parts of viscosity regulator, and 10 parts of the mixed grafting material, all the "parts" correspond to 0.5 kg.

[0043] The nitrile rubber is a raw material produced by Nantie Chemical Industry Co., Ltd., with a model of N3345, and an acrylonitrile content of 33wt%.

[0044] The vulcanizing agent is a mixture of sulfur and phenolic resin, the carbon black is Cabot carbon black, the antioxidant is a mixture of antioxidant RD and antioxidant BLE, and the viscosity regulator is a mixture of phthalate ester, paraffin oil, white oil, and polyethylene glycol.

[0045] The mixed grafting material is a mixture of graft-modified molybdenum disulfide and graft-modified polytetrafluoroethylene fine powder, which is prepared by a plasma-grafting method. The plasma-grafting method successively includes the following steps,

[0046] S1, plasma pretreatment: using a radio frequency plasma generator or a microwave plasma generator, the molybdenum disulfide and the polytetrafluoroethylene fine powder are treated together in an oxygen atmosphere to obtain an intermediate powder;

[0047] S2, chemical grafting treatment: the intermediate powder is prepared into a mixed solution, peroxide initiator and methyl methacrylate grafting monomer are added to the mixed solution, and then heating grafting operation is performed to obtain a grafting material;

[0048] S3, post-treatment: the grafting material is successively subjected to filtration, washing and drying operations to obtain a mixed grafting material composed of the graft-modified molybdenum disulfide and the graft-modified polytetrafluoroethylene fine powder.

[0049] In S1, the weight ratio of the molybdenum disulfide and the polytetrafluoroethylene micro powder is 1:1.4, the particle size of the molybdenum disulfide is 4.2-8.7 μm, and the particle size of the polytetrafluoroethylene micro powder is 3.1-3.7 μm.

[0050] In S1, the gas flow of the radio frequency plasma generator or the microwave plasma generator is 85 sccm, the power is 210 W, and the pretreatment time is 22 min.

[0051] In S2, the solvent of the mixed solution is toluene, and the temperature of the heating grafting operation is 80-85℃.

[0052] In addition, the production method of the rubber material sequentially comprises the following steps:

[0053] T1, the butyl nitrile rubber, carbon black, white carbon black, and mixed grafting material are put into a mixing mill, plasticized and uniformly mixed, then the antioxidant and viscosity regulator are added, mixed and uniformly mixed, and then discharged, cooled to obtain a masterbatch;

[0054] T2, the masterbatch is put into an open mill, the vulcanizing agent, zinc oxide, and stearic acid are added, mixed and uniformly mixed, and then discharged and cooled to obtain a final rubber;

[0055] T3, the final rubber is placed in a mold of a vulcanizing machine, vulcanized, cooled to room temperature after vulcanization, and demolded to obtain the rubber material with high wear resistance characteristics for pneumatic components.

[0056] In T1, the temperature of the plasticizing operation is 60℃, and the plasticizing time is 40 min; the temperature of the mixing operation is 90℃, and the mixing time is 20 min.

[0057] In T2, the temperature of the mixing operation is 35℃, and the mixing time is 15 min.

[0058] In T3, the vulcanization temperature is 85℃, and the vulcanization time is 35 min.

[0059] Finally, the mechanical properties and wear resistance of the rubber material in the embodiment are tested, and the test results are shown in Table 1.

[0060] Example 2

[0061] A rubber material with high wear resistance characteristics for pneumatic components, the raw material composition includes the following components by weight: butyl nitrile rubber 100 parts, vulcanizing agent 4.0 parts, zinc oxide 5 parts, stearic acid 1.5 parts, carbon black 68 parts, white carbon black 12 parts, antioxidant 3.5 parts, viscosity regulator 10 parts, and the mixed grafting material 11 parts, all the above "parts" correspond to 0.5 kg.

[0062] The nitrile rubber is raw material of N3345 produced by Nantai Chemical Industry Co., Ltd., and the acrylonitrile content is 33wt%.

[0063] The vulcanizing agent is a mixture of sulfur and benzoyl peroxide, the carbon black is Cabot carbon black, the antioxidant is a mixture of antioxidant RD and antioxidant BLE, and the viscosity regulator is a mixture of phthalate ester, paraffin oil, white oil and polyethylene glycol.

[0064] The mixed grafting material is a mixture of graft-modified molybdenum disulfide and graft-modified polytetrafluoroethylene micro powder, which is prepared by a plasma-grafting method. The plasma-grafting method comprises the following steps in sequence,

[0065] S1, plasma pretreatment: using a radio frequency plasma generator or a microwave plasma generator, the molybdenum disulfide and the polytetrafluoroethylene micro powder are treated by plasma in an oxygen atmosphere to obtain an intermediate powder;

[0066] S2, chemical grafting treatment: the intermediate powder is prepared into a mixed solution, peroxide initiator and methyl methacrylate grafting monomer are added to the mixed solution, and then heating grafting operation is performed to obtain a grafting material;

[0067] S3, post-treatment: the grafting material is sequentially subjected to filtration, washing and drying operations to obtain a mixed grafting material composed of the graft-modified molybdenum disulfide and the graft-modified polytetrafluoroethylene micro powder.

[0068] In S1, the weight ratio of the molybdenum disulfide and the polytetrafluoroethylene micro powder is 1:1.2, the particle size of the molybdenum disulfide is 4.2-8.7 μm, and the polytetrafluoroethylene micro powder is 3.2-3.5 μm.

[0069] In S1, the gas flow of the radio frequency plasma generator or the microwave plasma generator is 85 sccm, the power is 210 W, and the pretreatment time is 25 min.

[0070] In S2, the solvent of the mixed solution is toluene, and the temperature of the heating grafting operation is 90℃.

[0071] In addition, the production method of the rubber material comprises the following steps in sequence:

[0072] T1, the nitrile rubber, carbon black, white carbon black and mixed grafting material are put into a banbury mixer, plasticized and uniformly mixed, then the antioxidant and the viscosity regulator are added, mixed uniformly, discharged and cooled to obtain a masterbatch;

[0073] T2, put the masterbatch into an open mill, add vulcanizing agent, zinc oxide and stearic acid, mix uniformly, sheet out and cool to obtain a final rubber;

[0074] T3, put the final rubber into a mold of a vulcanizing machine, vulcanize, cool to room temperature after vulcanization, and demold to obtain the rubber material with high wear resistance for pneumatic components.

[0075] In T1, the plastication temperature is 65℃, and the plastication time is 40min; the mixing temperature is 95℃, and the mixing time is 20min.

[0076] In T2, the mixing temperature is 40℃, and the mixing time is 15min.

[0077] In T3, the vulcanization temperature is 110℃, and the vulcanization time is 35min.

[0078] Finally, the mechanical properties and wear resistance of the rubber material in the embodiment are tested, and the test results are shown in Table 1.

[0079] Example 3

[0080] A rubber material with high wear resistance for pneumatic components, the raw material composition of which comprises the following components by weight: 100 parts of nitrile rubber, 4.5 parts of vulcanizing agent, 5 parts of zinc oxide, 1.5 parts of stearic acid, 70 parts of carbon black, 12 parts of white carbon black, 3.5 parts of antioxidant, 10 parts of viscosity regulator, and 9 parts of mixed grafting material, all of which correspond to 0.5kg.

[0081] The nitrile rubber is produced by Nantai Chemical Industry Co., Ltd., and the model is N 3245C, and the acrylonitrile content is 32wt%.

[0082] The vulcanizing agent is a mixture of sulfur and benzoyl peroxide, the carbon black is Cabot carbon black, the antioxidant is a mixture of antioxidant RD and antioxidant BLE, and the viscosity regulator is a mixture of phthalate ester, paraffin oil, white oil, and polyethylene glycol.

[0083] The mixed grafting material is a mixture of graft-modified molybdenum disulfide and graft-modified polytetrafluoroethylene micro powder, which is prepared by a plasma-grafting method. The plasma-grafting method comprises the following steps in sequence,

[0084] S1, plasma pretreatment: using a radio frequency plasma generator or a microwave plasma generator, the molybdenum disulfide and the polytetrafluoroethylene micro powder are treated together in an oxygen atmosphere to obtain an intermediate powder;

[0085] S2, chemical grafting treatment: the intermediate powder is prepared into a mixed solution, a peroxide initiator and a methyl methacrylate grafting monomer are added into the mixed solution, and then a heating grafting operation is performed to obtain a grafted material;

[0086] S3, post-treatment: the grafted material is sequentially subjected to filtering, washing and drying operations to obtain a mixed grafted material composed of the grafted modified molybdenum disulfide and the grafted modified polytetrafluoroethylene micro powder.

[0087] In S1, the weight ratio of the molybdenum disulfide and the polytetrafluoroethylene micro powder is 1:1.5, the particle size of the molybdenum disulfide is 7.0-9.4 μm, and the particle size of the polytetrafluoroethylene micro powder is 3.2-3.5 μm.

[0088] In S1, the gas flow of the radio frequency plasma generator or the microwave plasma generator is 100 sccm, the power is 210 W, and the pretreatment time is 25 min.

[0089] In S2, the solvent of the mixed solution is toluene, and the temperature of the heating grafting operation is 90℃.

[0090] In addition, the production method of the rubber material sequentially comprises the following steps:

[0091] T1, the butyl nitrile rubber, carbon black, white carbon black, and mixed grafted material are put into a banbury mixer, plasticated uniformly, then the anti-aging agent and the viscosity regulator are added, mixed uniformly, and then discharged, cooled to obtain a master batch;

[0092] T2, the master batch is put into an open mill, the vulcanizing agent, zinc oxide and stearic acid are added, mixed uniformly, discharged, and cooled to obtain a final batch;

[0093] T3, the final batch is put into a mold of a vulcanizing machine, vulcanized, cooled to room temperature after vulcanization, and demolded to obtain the rubber material with high wear resistance characteristics which can be used for pneumatic components.

[0094] In T1, the temperature of the plasticating operation is 65℃, and the plasticating time is 30 min; the temperature of the mixing operation is 95℃, and the mixing time is 20 min.

[0095] In T2, the temperature of the mixing operation is 50℃, and the mixing time is 15 min.

[0096] In T3, the vulcanization temperature is 110℃, and the vulcanization time is 35 min.

[0097] Finally, the mechanical properties and wear resistance of the rubber material in the embodiment are tested, and the test results are shown in Table 1.

[0098] Example 4

[0099] A rubber material with high wear resistance characteristics, which can be used in pneumatic components, whose raw material composition comprises, by weight, the following components: 100 parts of nitrile rubber, 4.5 parts of vulcanizing agent, 6 parts of zinc oxide, 1.0 parts of stearic acid, 70 parts of carbon black, 12 parts of white carbon black, 3.5 parts of antioxidant, 10 parts of viscosity regulator, and 8 parts of the mixed grafting material, all of the above "parts" corresponding to 0.5 kg.

[0100] The nitrile rubber is a raw material produced by Nantai Chemical Industry Co., Ltd., with a model of N 3245C, and an acrylonitrile content of 32 wt%.

[0101] The vulcanizing agent is a mixture of sulfur and benzoyl peroxide, the carbon black is Cabot carbon black, the antioxidant is a mixture of antioxidant RD and antioxidant BLE, and the viscosity regulator is a mixture of phthalate ester, paraffin oil, white oil, and polyethylene glycol.

[0102] The mixed grafting material is a mixture of graft-modified molybdenum disulfide and graft-modified polytetrafluoroethylene micro powder, which is prepared by a plasma-grafting method. The plasma-grafting method comprises the following steps in sequence,

[0103] S1, plasma pretreatment: using a radio frequency plasma generator or a microwave plasma generator, the molybdenum disulfide and the polytetrafluoroethylene micro powder are treated together in an oxygen atmosphere to obtain an intermediate powder;

[0104] S2, chemical grafting treatment: the intermediate powder is prepared into a mixed solution, peroxide initiator and methyl methacrylate grafting monomer are added to the mixed solution, and then heating grafting operation is performed to obtain a grafting material;

[0105] S3, post-treatment: the grafting material is sequentially subjected to filtration, washing and drying operations to obtain a mixed grafting material composed of the graft-modified molybdenum disulfide and the graft-modified polytetrafluoroethylene micro powder.

[0106] In S1, the weight ratio of the molybdenum disulfide and the polytetrafluoroethylene micro powder is 1:1.5, the particle size of the molybdenum disulfide is 7.0-9.4 μm, and the polytetrafluoroethylene micro powder is 3.2-3.5 μm.

[0107] In S1, the gas flow of the radio frequency plasma generator or the microwave plasma generator is 100 sccm, the power is 210 W, and the pretreatment time is 15 min.

[0108] In S2, the solvent of the mixed solution is toluene, and the temperature of the heating grafting operation is 100°C.

[0109] In addition, the production method of the rubber material comprises the following steps in sequence:

[0110] T1, the nitrile rubber, carbon black, white carbon black, and mixed grafting material are put into a mixer, plasticized and uniformly mixed, then the antioxidant and viscosity modifier are added, mixed uniformly, discharged, cooled, and a masterbatch is obtained;

[0111] T2, the masterbatch is put into an open mill, the vulcanizing agent, zinc oxide, and stearic acid are added, mixed uniformly, discharged, and cooled to obtain a final rubber.

[0112] T3, the final rubber is placed in a mold of a vulcanizing machine, vulcanized, cooled to room temperature after vulcanization, and demolded to obtain the rubber material with high wear resistance for pneumatic components.

[0113] In T1, the plasticizing temperature is 65°C, and the plasticizing time is 30 min; the mixing temperature is 95°C, and the mixing time is 20 min.

[0114] In T2, the mixing temperature is 50°C, and the mixing time is 10 min.

[0115] In T3, the vulcanization temperature is 110°C, and the vulcanization time is 20 min.

[0116] Finally, the mechanical properties and wear resistance of the rubber material in this example are tested, and the test results are shown in Table 1.

[0117] Comparative Example 1

[0118] The rubber material in this comparative example and its production method are compared with Example 1, and only differ in the following 1 aspect.

[0119] The molybdenum disulfide and polytetrafluoroethylene micro powder in Example 1 are used to replace the mixed grafting material with equal weight, i.e. 2.08 kg of molybdenum disulfide and 2.92 kg of polytetrafluoroethylene micro powder.

[0120] Of course, the actual amount of molybdenum disulfide and polytetrafluoroethylene micro powder added at this time is more than that in Example 1.

[0121] Finally, the mechanical properties and wear resistance of the rubber material in this comparative example are also tested, and the test results are shown in Table 1.

[0122] Comparative Example 2

[0123] The rubber material in this comparative example and its production method are compared with Comparative Example 1, and only differ in the following 1 aspect.

[0124] The above-mentioned 2.92 kg of polytetrafluoroethylene micro powder is subjected to plasma-grafting operation alone to obtain a grafted modified polytetrafluoroethylene micro powder, which is used together with 2.08 kg of molybdenum disulfide.

[0125] Finally, the rubber material in the present comparative example was also subjected to mechanical property and wear resistance tests, and the test results are shown in Table 1.

[0126] Comparative Example 3

[0127] The rubber material in the present comparative example, and its production method, only has the following 1 difference compared with Comparative Example 1.

[0128] The 2.08 kg of molybdenum disulfide was subjected to a plasma-grafting operation alone to obtain a graft-modified molybdenum disulfide, which was used together with 2.92 kg of polytetrafluoroethylene micro powder.

[0129] Finally, the rubber material in the present comparative example was also subjected to mechanical property and wear resistance tests, and the test results are shown in Table 1.

[0130] Comparative Example 4

[0131] The rubber material in the present comparative example, and its production method, only has the following 1 difference compared with Example 1.

[0132] The mixed grafting material was not used at all, i.e. in T1, the nitrile rubber was added together with carbon black and white carbon black.

[0133] Finally, the rubber material in the present comparative example was also subjected to mechanical property and wear resistance tests, and the test results are shown in Table 1.

[0134] Comparative Example 5

[0135] The rubber material in the present comparative example, and its production method, only has the following 1 difference compared with Example 1.

[0136] In the plasma-grafting method, the plasma pretreatment was not performed, and the molybdenum disulfide and the polytetrafluoroethylene micro powder were directly subjected to grafting treatment. Of course, the final mixed grafting material can be considered as a “single grafting material” in nature.

[0137] Finally, the rubber material in the present comparative example was also subjected to mechanical property and wear resistance tests, and the test results are shown in Table 1.

[0138] Comparative Example 6

[0139] The rubber material in the present comparative example, and its production method, only has the following 1 difference compared with Example 1.

[0140] In the plasma-grafting method, the chemical grafting treatment was not performed, and the intermediate powder was directly subjected to washing and drying operations. Of course, the final mixed grafting material can be considered as a “single plasma material” in nature.

[0141] Finally, the rubber material in the present comparative example was also subjected to mechanical property and wear resistance tests, and the test results are shown in Table 1.

[0142] Comparative Example 7

[0143] The rubber material in the present comparative example, and the production method thereof, only differs from Example 1 in the following 1 aspect.

[0144] The anti-aging agent and viscosity modifier were not used at all, i.e. in T1, after uniform plastication, the mixing operation was directly performed.

[0145] Finally, the rubber material in the present comparative example was also subjected to mechanical property and wear resistance tests, and the test results are shown in Table 1.

[0146] Performance tests

[0147] The above-mentioned 4 examples and 7 comparative examples each took 7 rubber samples, i.e. a total of 77 rubber samples.

[0148] Among the 7 rubber samples of each example / comparative example, 5 rubber samples were used for mechanical property tests, and the average value was recorded in Table 1, and 2 rubber samples were used for wear resistance tests, and the average value was also recorded in Table 1.

[0149] Table 1 Average test results of mechanical properties and wear resistance Hardness (shore A) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) 60±5 ＞250 ＞15 ＞3 Tensile strength (MPa) Tensile strength (MPa) 63 330 17.8 4.2 1500 Tensile strength (MPa) 62 285 16.4 4.5 1500 Tensile strength (MPa) 59 302 17.2 4.5 1700 Tensile strength (MPa) 64 297 17.7 4.0 1600 Tensile strength (MPa) 60 265 16.5 4.0 1000 Tensile strength (MPa) 61 251 11.5 4.7 900 Tensile strength (MPa) 61 327 14.0 5.0 1100 Tensile strength (MPa) 65 309 16.8 4.2 600 Tensile strength (MPa) 62 304 17.0 4.1 1200 Tensile strength (MPa) 57 305 17.1 2.8 1100 Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tensile strength (MPa) Tens 65 215 14.2 2.7 1600

[0150] Data analysis

[0151] First, the rubber materials in the 4 examples all have sufficient mechanical properties and outstanding wear resistance, and the specific level of the latter is that the number of times of motion fatigue wear without air leakage is at least 15 million times, and the comprehensive performance is obviously improved compared with the 7 comparative examples.

[0152] Second, the rubber materials in Comparative Examples 1-6 all have substantial process parameter changes in the mixed grafting material part compared with the examples, resulting in that the wear resistance of the rubber materials in the 6 comparative examples is far inferior to that of the examples, which proves from the negative side that the mixed grafting material in the examples can provide outstanding wear resistance.

[0153] Third, the rubber material in Comparative Example 4 does not include molybdenum disulfide and polytetrafluoroethylene micro powder at all in the formula composition, so its wear resistance is relatively the worst, which proves that even if the molybdenum disulfide and polytetrafluoroethylene micro powder are not modified, they also have a significant wear resistance improvement effect.

[0154] Fourthly, from the comparative examples 1, 2, 3, 5, 6, it can be seen that the integrity of the above-mentioned plasma-grafting method is also necessary for the improvement of the wear resistance of the rubber material.

[0155] Fifthly, the auxiliary system in the rubber formula has little effect on the above-mentioned wear resistance, but it will affect the above-mentioned mechanical properties, so it is also necessary for the production of the pneumatic rubber element.

[0156] Sixthly, the unqualified problem of a single index in the mechanical properties of the rubber material in the comparative examples 1-6 can be considered as an occasional phenomenon.

[0157] The above has made a detailed description of the embodiments of the present application, but the present application is not limited to the above-mentioned embodiments, and various modifications can be made within the knowledge range of ordinary skilled persons in the art without departing from the purpose of the present application. These are not creative modifications, and are protected by the patent law within the scope of the claims of the present application.

Claims

1. Rubber material with high wear resistance characteristics, usable in pneumatic elements, characterized in that The raw material composition comprises the following components, grafted modified molybdenum disulfide and grafted modified polytetrafluoroethylene micro powder, wherein the grafted modified molybdenum disulfide and the grafted modified polytetrafluoroethylene micro powder are prepared together by the following plasma-grafting method, S1, plasma pretreatment: using a radio frequency plasma generator or a microwave plasma generator, the molybdenum disulfide and the polytetrafluoroethylene micro powder are treated together in an oxygen atmosphere to obtain intermediate powder; S2, chemical grafting treatment: the intermediate powder is prepared into a mixed solution, a peroxide initiator and a methyl methacrylate grafting monomer are added into the mixed solution, and then a heating grafting operation is performed to obtain a grafted material; S3, post-treatment: the grafted material is sequentially subjected to filtration, washing and drying operations to obtain a mixed grafted material composed of the grafted modified molybdenum disulfide and the grafted modified polytetrafluoroethylene micro powder.

2. A rubber material having high wear resistance characteristics, useful in pneumatic elements according to claim 1, characterized in that: In S1, the weight ratio of the molybdenum disulfide and the polytetrafluoroethylene micro powder is 1: (1.2-1.5), the particle size of the molybdenum disulfide is 4.0-10.5 μm, and the polytetrafluoroethylene micro powder is 3.0-4.0 μm.

3. A rubber material having high wear resistance characteristics, useful in pneumatic elements according to claim 2, characterized in that: In S1, the gas flow of the radio frequency plasma generator or the microwave plasma generator is 50-100 sccm, the power is 200-500 W, and the pretreatment time is 15-25 min.

4. A rubber material having high wear resistance characteristics for use in pneumatic elements according to claim 1, characterized in that: In S2, the solvent of the mixed solution is any one of water, ethanol, toluene, methyl ethyl ketone and ethyl acetate, and the temperature of the heating grafting operation is 75-110°C.

5. A rubber material having high wear resistance characteristics for use in pneumatic elements according to claim 1, characterized in that The raw material composition comprises the following components: nitrile rubber, a vulcanizing agent system, carbon black, white carbon black, an auxiliary agent system, and the mixed grafted material, wherein the vulcanizing agent system comprises a vulcanizing agent, a vulcanizing aid zinc oxide, and a vulcanizing aid stearic acid, and the auxiliary agent system comprises an antioxidant and a viscosity regulator.

6. A rubber material having high wear resistance characteristics, useful in pneumatic elements according to claim 5, characterized in that The raw material composition comprises the following components by weight: nitrile rubber 100 parts, vulcanizing agent 3.5-4.5 parts, zinc oxide 5-6 parts, stearic acid 0.5-1.5 parts, carbon black 60-70 parts, white carbon black 10-15 parts, antioxidant 2.5-3.5 parts, viscosity regulator 7-10 parts, and the mixed grafted material 5-11 parts.

7. A rubber material having high wear resistance characteristics for use in pneumatic elements according to claim 6, characterized in that: The acrylonitrile content of the nitrile rubber is 30-35 wt%.

8. A rubber material having high wear resistance characteristics for use in pneumatic elements according to claim 6, characterized in that: The vulcanizing agent is any one or mixture of several of sulfur, dicumyl peroxide, benzoyl peroxide, phenolic resin, and benzophenone dioxime.

9. A rubber material having high wear resistance characteristics for use in pneumatic elements according to claim 6, characterized in that: The antioxidant is a mixture of antioxidant RD and antioxidant BLE, and the viscosity regulator is a mixture of phthalate, paraffin oil, white oil, and polyethylene glycol.

10. A rubber material having high wear resistance characteristics for use in pneumatic elements according to claim 6, characterized in that The production method comprises the following steps in sequence: T1, the nitrile rubber, carbon black, white carbon black, and mixed grafted material are put into a banbury mixer, uniformly plasticated, then the antioxidant and the viscosity regulator are added, uniformly mixed, discharged, and cooled to obtain a masterbatch; T2, the masterbatch is put into an open mill, the vulcanizing agent, zinc oxide, and stearic acid are added, uniformly mixed, discharged, and cooled to obtain a final batch; T3, the final rubber compound is put into the mold of the vulcanizing machine, vulcanization is carried out, after vulcanization is completed, cooling is carried out to room temperature, and demolding is carried out to obtain the rubber material with high wear resistance characteristics, which can be used for pneumatic components.