Rubber composition for rollers and preparation method thereof

Abstract

The preparation method comprises the following steps: plastifying smoked sheet rubber RSS3 # in an internal mixer for 5 minutes, discharging rubber, discharging sheets, cooling, adding the plastified smoked sheet rubber RSS3 #, butadiene rubber BR9000, trans-butadiene-isoprene rubber TBIR2249 and a master batch powder bag into the internal mixer according to basic parts, and mixing for 2 minutes; adding a silane coupling agent Si69 and a white carbon black dispersing agent ST into the internal mixer, lifting a top peg, adding high-dispersion white carbon black 1165 MP, the silane coupling agent Si69 and the white carbon black dispersing agent ST into the internal mixer, pressing the top peg, and mixing for 5 minutes; lifting the top peg, adding carbon black N550 into the internal mixer, and mixing for 1 minute; discharging rubber, discharging sheets and standing to prepare master batch; and adding the master batch and the final mixing powder bag into the internal mixer, and mixing for 2 minutes to prepare the final mixing rubber. The rubber with high fatigue resistance is successfully developed by optimizing a raw rubber system. The vulcanized rubber has very excellent fatigue resistance, moderate rigidity and good wear resistance under dynamic load, solves the problem of insufficient dynamic fatigue performance of traditional vulcanized rubber, and provides a new scheme for improving the performance of rubber products.

Description

Technical Field

[0001] The present invention relates to the technical field of rubber materials, and particularly relates to a rubber composition for rollers and a preparation method thereof. Background Art

[0002] The roller guide shoe uses a rubber roller, which can effectively absorb the impact and vibration during operation, reduce noise, and improve the riding comfort. The rollers in the roller guide shoes are usually made of wear-resistant rubber and can still maintain good performance under the condition of long-term contact and friction with the guide rail. The performance of the rubber material needs to meet certain stiffness, wear resistance, and fatigue life. For the roller guide shoe, appropriate stiffness can ensure that it stably adheres to the guide rail during the operation of the elevator, reduce the vibration and noise caused by deformation, and at the same time ensure good contact between the guide shoe and the guide rail, improving the smoothness and safety of the elevator operation. Since the guide shoe will continuously contact and roll with the guide rail during the operation of the elevator and bear periodic load effects, the fatigue life is an important index to measure the durability and reliability of the roller guide shoe. The roller guide shoe with good wear resistance can provide stable support and guidance during the operation of the elevator, reduce the vibration and noise caused by roller wear, and improve the smoothness and comfort of the elevator operation.

[0003] Therefore, it is an urgent problem to be solved to develop a rubber composition with excellent dynamic fatigue life, moderate stiffness, good wear resistance, and other high performances for elevator rollers. Summary of the Invention

[0004] In view of the above problems, the present invention provides a rubber composition for rollers, which has the properties of low compression set, high fatigue life, and moderate stiffness, meeting the use requirements of elevator rollers.

[0005] To achieve the above object, the following technical solutions are adopted: A rubber composition for rollers, comprising the following components in parts by weight: 70 - 100 parts of smoked sheet rubber RSS3#, 0 - 20 parts of cis-butadiene rubber BR9000, 0 - 20 parts of trans-butyl pentene rubber TBIR2249, 10 parts of carbon black N550, 45 parts of highly dispersed precipitated silica 1165MP, 5 parts of silane coupling agent Si69, 5 parts of zinc oxide, 2 parts of stearic acid, 2 parts of microcrystalline wax A654, 2 parts of precipitated silica dispersant ST, 3 parts of antioxidant 4020, 2 parts of antioxidant RD, 1.2 parts of vulcanizing agent S-80, 2.1 parts of accelerator CBS-80, 1.2 parts of accelerator TMTD-80, 0.6 part of crosslinking agent DCP, and 0.5 part of accelerator DPG.

[0006] Preferably, the weight parts of each component are as follows: 70 parts of smoked sheet rubber RSS3#, 10 parts of cis-butadiene rubber BR9000, 20 parts of trans-butyl pentene rubber TBIR2249, 10 parts of carbon black N550, 45 parts of highly-dispersed silica 1165MP, 5 parts of silane coupling agent Si69, 5 parts of zinc oxide, 2 parts of stearic acid, 2 parts of microcrystalline wax A654, 2 parts of silica dispersant ST, 3 parts of antioxidant 4020, 2 parts of antioxidant RD, 1.2 parts of vulcanizing agent S-80, 2.1 parts of accelerator CBS-80, 1.2 parts of accelerator TMTD-80, 0.6 parts of crosslinking agent DCP, and 0.5 parts of accelerator DPG.

[0007] The present invention also provides a method for preparing a rubber composition for a roller, which comprises the following steps:

[0008] S1. Plasticate the smoked sheet rubber RSS3# in a mixer according to the weight ratio of each component in the rubber composition, control the rubber temperature at 110-120°C, plasticate for 5 minutes, and take out the sheet for standby after discharging the rubber.

[0009] S2. Add the plasticated smoked sheet rubber RSS3# from S1 into the mixer according to the ratio, and at the same time add cis-butadiene rubber BR9000, trans-butyl pentene rubber TBIR2249, and the masterbatch powder bag into the mixer according to the weight ratio of each component in the rubber composition. The masterbatch powder bag includes zinc oxide, stearic acid, microcrystalline wax A654, antioxidant RD, and antioxidant 4020. Press the upper plug, and the mixing time is 1-2 minutes. When the mixing temperature reaches 100-110°C, lift the upper plug; then add highly-dispersed silica 1165MP, silane coupling agent Si69, and silica dispersant ST into the mixer according to the ratio, press the upper plug, mix for 4.5-5 minutes, lift the upper plug to exhaust 3 times, and when the mixing temperature reaches 135-140°C, lift the upper plug again; add carbon black N550 into the mixer according to the ratio, press the upper plug, and the mixing time is 1 minute. When the mixing temperature reaches 145°C, discharge the rubber and take out the sheet for standing to prepare the masterbatch rubber.

[0010] S3. Add the masterbatch rubber prepared in S2 into the mixer, and at the same time add the final compounding powder bag into the mixer according to the weight ratio of each component in the rubber composition. The final compounding powder bag includes accelerator CBS-80, accelerator DPG, crosslinking agent DCP, vulcanizing agent S-80, and accelerator TMTD-80. Mix for 2 minutes. When the temperature of the mixed rubber reaches 90-95°C, discharge the rubber and take out the sheet for standing to prepare the final compounding rubber.

[0011] The beneficial effects of the present invention are:

[0012] Preferably, for the raw rubber system in the rubber formulation, three rubbers are used in combination (RSS3# smoked sheet rubber + BR9000 cis-butadiene rubber + TBIR2249 trans-butyl pentene rubber). TBIR is a high trans-1,4-structured polymer material copolymerized from isoprene and butadiene. It can significantly improve the compatibility of general rubbers such as natural rubber, cis-butadiene rubber, and styrene-butadiene rubber, and optimize the dispersion effect of reinforcing agents in the mixed rubber, thereby enhancing the fatigue resistance and abrasion resistance of the vulcanized rubber. In the filler system of the rubber formulation, silica and silane coupling agent are used to improve the dynamic heat generation of the product. In the vulcanization system of the rubber formulation, a mixed vulcanization system of sulfur and peroxide is used to reduce the compression set of the vulcanized rubber. On the premise of ensuring appropriate stiffness and low compression set, the present invention significantly improves the dynamic fatigue life of the roller guide shoe, filling the shortcoming of the rubber material performance in high dynamic load scenarios. Brief Description of the Drawings

[0013] Figure 1 It is a schematic diagram of the production process flow of the present invention. Detailed Embodiments

[0014] The rubber composition for the roller of the technical solution of the present invention comprises the following components in parts by weight: 70-100 parts of RSS3# smoked sheet rubber, 0-20 parts of BR9000 cis-butadiene rubber, 0-20 parts of TBIR2249 trans-butyl pentene rubber, 10 parts of carbon black N550, 45 parts of highly dispersed silica 1165MP, 5 parts of silane coupling agent Si69, 5 parts of zinc oxide, 2 parts of stearic acid, 2 parts of microcrystalline wax A654, 2 parts of silica dispersant ST, 3 parts of antioxidant 4020, 2 parts of antioxidant RD, 1.2 parts of vulcanizing agent S-80, 2.1 parts of accelerator CBS-80, 1.2 parts of accelerator TMTD-80, 0.6 part of crosslinking agent DCP, and 0.5 part of accelerator DPG.

[0015] S1. Plasticate the RSS3# smoked sheet rubber in a mixer according to the weight ratio of each component in the rubber composition, control the rubber temperature at 110-120 °C, plasticate for 5 min, and discharge the rubber and then take out the sheet for standby;

[0016] S2. Add the plasticized smoked sheet rubber RSS3# in S1 into the internal mixer according to the proportion by parts, and at the same time add cis-butadiene rubber BR9000, trans-butyl pentene rubber TBIR2249, and the masterbatch powder bag into the internal mixer according to the weight proportion by parts of each component in the rubber composition. The masterbatch powder bag includes zinc oxide, stearic acid, microcrystalline wax A654, antioxidant RD, and antioxidant 4020. Press the upper ram, and the mixing time is 1 - 2 min. When the mixing temperature reaches 100 - 110 °C, lift the upper ram; then add highly dispersed silica 1165MP, silane coupling agent Si69, and silica dispersant ST into the internal mixer according to the proportion by parts, press the upper ram, mix for 4.5 - 5 min, lift the upper ram to exhaust 3 times, and when the mixing temperature reaches 135 - 140 °C, lift the upper ram again; add carbon black N550 into the internal mixer according to the proportion by parts, press the upper ram, and when the mixing time is 1 min and the mixing temperature reaches 145 °C, discharge the rubber and take out the sheet for parking to make the masterbatch rubber;

[0017] S3. Add the masterbatch rubber obtained in S2 into the internal mixer, and at the same time add the final mixing powder bag into the internal mixer according to the weight proportion by parts of each component in the rubber composition. The final mixing powder bag includes accelerator CBS-80, accelerator DPG, crosslinking agent DCP, vulcanizing agent S-80, and accelerator TMTD-80. Mix for 2 min. When the temperature of the mixed rubber reaches 90 - 95 °C, discharge the rubber and take out the sheet for parking to make the final mixing rubber. The technical solution of the present invention will be further described below with reference to the embodiments.

[0018] Prepare the rubber composition for the roller according to the preparation method proposed by the present invention, and the parts of each component are as shown in Table 1 below,

[0019] In Examples 1 - 5, different raw rubber systems are used in combination.

[0020] Table 1 Comparison of Examples

[0021] Example 1 Example 2 Example 3 Example 4 Example 5 RSS3# smoked sheet rubber 100 80 80 70 70 BR9000 cis-butadiene rubber 0 20 10 20 10 TBIR2249 trans-butyl pentadiene rubber 0 0 10 10 20 zinc oxide 5 5 5 5 5 stearic acid 2 2 2 2 2 microcrystalline wax A654 2 2 2 2 2 ST white carbon black dispersant 2 2 2 2 2 N550 carbon black 10 10 10 10 10 1165MP white carbon black 45 45 45 45 45 Si69 silane coupling agent 5 5 5 5 5 antioxidant 4020 3 3 3 3 3 antioxidant RD 2 2 2 2 2 TMTD-80 accelerator 1.2 1.2 1.2 1.2 1.2 DCP crosslinking agent 0.6 0.6 0.6 0.6 0.6 S-80 vulcanizing agent 1.2 1.2 1.2 1.2 1.2 DPG accelerator 0.5 0.5 0.5 0.5 0.5 CBS-80 accelerator 2.1 2.1 2.1 2.1 2.1

[0022] In the rubber compositions of Examples 1 - 5, the raw rubber uses a combination of smoked sheet rubber RSS3#, cis-butadiene rubber BR9000, and trans-butyl pentene rubber TBIR2249; for the filler system, a combination of carbon black N550 and silica is used; for the vulcanization system, a mixed vulcanization of sulfur and peroxide is used, and the performance indexes and evaluations of the obtained rubber compositions are shown in Table 2,

[0023] Table 2 Comparison of Performance Indexes

[0024]

[0025] As can be seen from the comprehensive comparison table 2, Example 5 (RSS3#: 70 parts + BR9000: 10 parts + TBIR2249: 20 parts) is the optimal solution with the best comprehensive performance. The proportion of TBIR in Example 5 is 20%. The compression set resistance and fatigue resistance (flex fatigue and roller fatigue) of the rubber are significantly improved, mainly due to the inhibition of molecular slip and the hindrance of crack propagation by its trans molecular chain structure. The filler is mainly silica, which reduces the heat generation of the filler. The vulcanization system uses a mixture of sulfur and peroxide for vulcanization to balance the crosslink density and network stability and reduce local stress concentration. Through reasonable formulation design, rubber products with low compression set, high fatigue life, and moderate stiffness can be obtained, meeting the standard usage requirements.

[0026] Although the embodiments of the present invention have been shown and described above, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A rubber composition for a roller, characterized in that, Components and parts by weight included: 70 - 100 parts of smoked sheet rubber RSS3#, 0 - 20 parts of cis-butadiene rubber BR9000, 0 - 20 parts of trans-butyl pentene rubber TBIR2249, 10 parts of carbon black N550, 45 parts of highly dispersed silica 1165MP, 5 parts of silane coupling agent Si69, 5 parts of zinc oxide, 2 parts of stearic acid, 2 parts of microcrystalline wax A654, 2 parts of silica dispersant ST, 3 parts of antioxidant 4020, 2 parts of antioxidant RD, 1.2 parts of vulcanizing agent S-80, 2.1 parts of accelerator CBS-80, 1.2 parts of accelerator TMTD-80, 0.6 parts of crosslinking agent DCP, 0.5 parts of accelerator DPG.

2. The rubber composition for a roller according to claim 1, characterized in that, Parts by weight of the above-mentioned components: 70 parts of smoked sheet rubber RSS3#, 10 parts of cis-butadiene rubber BR9000, 20 parts of trans-butyl pentene rubber TBIR2249, 10 parts of carbon black N550, 45 parts of highly dispersed silica 1165MP, 5 parts of silane coupling agent Si69, 5 parts of zinc oxide, 2 parts of stearic acid, 2 parts of microcrystalline wax A654, 2 parts of silica dispersant ST, 3 parts of antioxidant 4020, 2 parts of antioxidant RD, 1.2 parts of vulcanizing agent S-80, 2.1 parts of accelerator CBS-80, 1.2 parts of accelerator TMTD-80, 0.6 parts of crosslinking agent DCP, 0.5 parts of accelerator DPG.

3. A method for preparing a rubber composition for a roller as described in claim 1, characterized in that, The steps are as follows: S1. Plasticate the smoked sheet rubber RSS3# in a mixer according to the weight ratio of each component in the rubber composition, control the rubber temperature at 110 - 120 °C, plasticate for 5 min, and take out the sheet for standby after discharging the rubber. S2. Add the plasticated smoked sheet rubber RSS3# from S1 into the mixer according to the proportion by weight, and add cis-butadiene rubber BR9000, trans-butyl pentene rubber TBIR2249 and the masterbatch powder bag into the mixer according to the weight ratio of each component in the rubber composition. The masterbatch powder bag includes zinc oxide, stearic acid, microcrystalline wax A654, antioxidant RD and antioxidant 4020. Press the upper ram, and the mixing time is 1.5 - 2 min. When the mixing temperature reaches 100 - 110 °C, lift the upper ram; then add highly dispersed silica 1165MP, silane coupling agent Si69 and silica dispersant ST into the mixer according to the proportion by weight, press the upper ram, mix for 4.5 - 5 min, lift the upper ram to exhaust 3 times, and when the mixing temperature reaches 135 - 140 °C, lift the upper ram again; add carbon black N550 into the mixer according to the proportion by weight, press the upper ram, and when the mixing time is 1 min and the mixing temperature reaches 145 °C, discharge the rubber and take out the sheet for standing, thus making the masterbatch rubber. S3. Add the masterbatch rubber obtained in S2 into the mixer, and at the same time add the final compounding powder bag into the mixer according to the weight ratio of each component in the rubber composition. The final compounding powder bag includes accelerator CBS-80, accelerator DPG, crosslinking agent DCP, vulcanizing agent S-80 and accelerator TMTD-80, mix for 2 min, and when the temperature of the mixed rubber reaches 90 - 95 °C, discharge the rubber and take out the sheet for standing, thus making the final compounded rubber.

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