A modified rubber powder, a method for preparing the same and applications thereof

Abstract

The application belongs to the technical field of rubber preparation, and particularly relates to a modified rubber powder, a preparation method and application thereof. The raw material of the modified rubber powder comprises the following components: waste rubber powder, additives, reinforcing agents and surfactants. The preparation method of the modified rubber powder comprises the following steps: first, waste rubber powder is soaked with additives, ultrasonic treatment, static stratification, removal of supernatant, water washing, removal of water, and then pre-treatment waste rubber powder is obtained; then, the pre-treatment waste rubber powder, reinforcing agents and surfactants are mixed, and after uniform mixing, drying and grinding through an 80-100 mesh sieve, the modified rubber powder is obtained. The prepared modified rubber powder has high tensile strength, high elongation at break and high wear resistance, and has a good application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber preparation, and particularly relates to modified rubber powder, a preparation method and application thereof. Background Art

[0002] The resource recovery and harmless treatment of waste tire rubber can not only effectively alleviate the current pressure of environmental pollution caused by waste rubber, but also play an important role in solving the shortage of rubber resources. Waste rubber powder is an important type of waste rubber recycling product. The development of deep processing technology for rubber powder is an important technical approach to achieve high-value utilization of waste rubber. Rubber powder is treated by physical, chemical or biological methods so that the modified rubber powder can form a good bond with the matrix material. During the two-phase melt blending process, the rubber powder can be better dispersed in the matrix material, resulting in significantly improved performance of the composite material. Through modification, the use value of rubber powder can be increased and its application field can be broadened, which has important theoretical and practical significance for the large-scale industrial application of rubber powder.

[0003] Chinese invention patent application CN117209947A discloses a composite modified EPDM rubber material for water pipe sealing and its preparation method. The composite modified EPDM rubber material comprises modified EPDM rubber powder and a polymer filler; the polymer filler comprises modified polyvinyl chloride powder and ethyl acrylate rubber powder. In the present invention, EPDM rubber is grafted with di[2-(acryloyloxy)ethyl]phosphate to obtain the modified EPDM rubber powder, polyvinyl chloride is grafted with methacrylate to obtain the modified polyvinyl chloride, and the ethyl acrylate rubber is surface-activated with a surfactant. Finally, the composite modified EPDM rubber material is blended and modified. The technical solution provided by the invention improves the compatibility between the three materials, overcomes the shortcomings of conventional water pipe sealing rubber materials, and enhances water resistance, corrosion resistance, and chloramine resistance.

[0004] Chinese invention patent application CN116496558A discloses a modified rubber powder and a preparation method thereof. The modified nano-Al2O3 / carbon fiber is prepared by acid washing carbon fibers, in-situ coating with Al2O3, treating with a silane coupling agent, and modifying with cystamine. 100 parts of rubber powder and 10 to 15 parts of the modified nano-Al2O3 / carbon fiber are then weighed and added to an internal mixer. 5 to 10 parts of methyl methacrylate, 5 to 10 parts of calcium carbonate, and 0.2 to 0.6 parts of sodium persulfate are then added. The mixture is swollen and mixed uniformly, and then reacted. After the reaction is completed, the product is ground and sieved to obtain the modified rubber powder. The modified rubber powder has good tensile strength, elongation at break, and wear resistance.

[0005] The existing technology has explored the preparation of rubber powder to some extent and has made some progress. However, there is still a lot of room for development of fine rubber powder, and its performance needs to be further improved and enhanced. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the present invention provides a modified rubber powder with high tensile strength, high elongation at break and excellent wear resistance.

[0007] In order to achieve the purpose of the present invention, the technical solutions adopted are as follows:

[0008] A modified rubber powder, the raw materials of which include the following components: waste rubber powder, additives, reinforcing agents and surfactants.

[0009] Preferably, the raw materials of the rubber powder include the following components in parts by weight: 90-110 parts of waste rubber powder, 1-5 parts of additives, 10-20 parts of reinforcing agents, 0.5-1 parts of silane coupling agents and 5-10 parts of surfactants.

[0010] Preferably, the auxiliary agent comprises, by mass percentage, 5%-10% polyoxyethylene nonylphenol ether, 5%-10% sodium oleate, 1-5% oxalic acid, and the balance is water.

[0011] Preferably, the reinforcing agent is one or more of modified kaolin, modified bentonite, and nano-silicon dioxide; and the surfactant is selected from sodium lauryl sulfate.

[0012] Preferably, the reinforcing agent is nano-modified kaolin;

[0013] Preferably, the preparation method of the nano-modified kaolin comprises dispersing kaolin in a 30-50% volume concentration ethanol aqueous solution, adding a silane coupling agent, mixing, stirring at 50-70° C. for 30-50 minutes, filtering, drying, grinding, and sieving to obtain the nano-modified kaolin.

[0014] Preferably, the silane coupling agent is γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.2-0.5, and the mass ratio of kaolin to the silane coupling agent is 1:0.05-0.1.

[0015] A second object of the present invention is to provide a method for preparing the modified rubber powder, comprising the following steps:

[0016] (1) soaking the waste rubber powder with an additive, ultrasonicating, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0017] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed and kneaded evenly, dried and ground through an 80-100 mesh sieve to obtain the product.

[0018] Preferably, the soaking time in step (1) is 5-10 minutes, and the ultrasonication time is 10-30 minutes.

[0019] Preferably, the mixing temperature in step (2) is 130-145° C. and the mixing time is 20-45 min.

[0020] The third object of the present invention is to provide the use of the modified rubber powder or the modified rubber powder obtained by the above preparation method in the preparation of tires, concrete or cables.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The present invention uses a compound silane coupling agent to modify kaolin, and the homemade modified kaolin is used for the preparation of rubber powder, which ultimately significantly enhances the reinforcing effect of the rubber powder. By introducing specific compound functional groups, the surface morphology is made looser, and the wear resistance and tensile strength of the rubber obtained are significantly improved.

[0023] (2) The present invention also focuses on the study of additives and finds that pre-treatment of waste rubber powder by adding the solution system of the present invention before modifying the rubber powder can improve the purity and performance of the waste rubber powder and effectively improve the tensile strength and anti-tensile strength of the later rubber.

[0024] (3) The present invention improves the performance of rubber powder through the improvement of the formula and preparation process, and also realizes the recycling and reuse of waste rubber powder. It achieves the reduction, reuse and resource utilization of rubber powder, and promotes the construction of "resource-saving and environmentally friendly" fine rubber powder preparation. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to specific embodiments. The following raw materials are all commercially available conventional raw materials. The supplier of the above waste rubber powder is Gaoxian Huagui Mining Co., Ltd., and the supplier of kaolin is Lingshou Jushi Mineral Products Processing Plant.

[0026] Example 1

[0027] A modified rubber powder comprises the following raw materials, calculated by weight: 100 parts of waste rubber powder, 3 parts of additives, 15 parts of reinforcing agents and 7 parts of surfactants.

[0028] The additives are calculated by mass percentage as follows: 8% polyoxyethylene nonylphenol ether, 8% sodium oleate, 2% oxalic acid, and the balance is water.

[0029] The surfactant is selected from sodium lauryl sulfate.

[0030] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin is as follows: dispersing kaolin in an ethanol aqueous solution with a volume concentration of 45%, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane with a mass ratio of 1:0.4) 0.05 times the mass of kaolin, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve.

[0031] The preparation method of modified rubber powder is as follows:

[0032] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0033] (2) The pretreated waste rubber powder, reinforcing agent and surfactant were mixed at 130°C for 45 minutes. After mixing evenly, the mixture was dried and ground through an 80-mesh sieve.

[0034] Example 2

[0035] A modified rubber powder comprises the following raw materials, calculated by weight: 90 parts of waste rubber powder, 1 part of an auxiliary agent, 10 parts of a reinforcing agent and 5 parts of a surfactant.

[0036] The additives are calculated by mass percentage as follows: 5% polyoxyethylene nonylphenol ether, 10% sodium oleate, 1% oxalic acid, and the balance is water.

[0037] The surfactant is selected from sodium lauryl sulfate.

[0038] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin is as follows: dispersing kaolin in a 30% ethanol aqueous solution, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.2) 0.05 times the mass of kaolin, stirring at 50°C for 30 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve to obtain the obtained product.

[0039] The preparation method of modified rubber powder comprises the following steps:

[0040] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0041] (2) The pretreated waste rubber powder, reinforcing agent and surfactant were mixed at 145°C for 20 minutes. After mixing evenly, the mixture was dried and ground through a 100-mesh sieve.

[0042] Example 3

[0043] A modified rubber powder comprises the following components, calculated by weight: 110 parts of waste rubber powder, 5 parts of additives, 20 parts of reinforcing agents and 10 parts of surfactants.

[0044] The additives are calculated by mass percentage as follows: 10% polyoxyethylene nonylphenol ether, 5% sodium oleate, 5% oxalic acid, and the balance is water.

[0045] The surfactant is selected from sodium lauryl sulfate.

[0046] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin includes dispersing kaolin in an ethanol aqueous solution with a volume concentration of 50%, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane with a mass ratio of 1:0.5) 0.1 times the mass of kaolin, stirring at 70°C for 50 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve to obtain the reinforcing agent.

[0047] The preparation method of modified rubber powder comprises the following steps:

[0048] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0049] (2) The pretreated waste rubber powder, reinforcing agent and surfactant were mixed at 130°C for 45 minutes. After mixing evenly, the mixture was dried and ground through an 80-mesh sieve.

[0050] Comparative Example 1

[0051] This comparative example differs from Example 1 in that the auxiliary agents are different.

[0052] A modified rubber powder comprises the following raw materials, calculated by weight: 100 parts of waste rubber powder, 3 parts of additives, 15 parts of reinforcing agents and 7 parts of surfactants.

[0053] The additives are calculated by mass percentage as follows: 16% polyoxyethylene nonylphenol ether, 2% oxalic acid, and the balance is water.

[0054] The surfactant is selected from sodium lauryl sulfate.

[0055] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin is as follows: dispersing kaolin in an ethanol aqueous solution with a volume concentration of 45%, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane with a mass ratio of 1:0.4) 0.05 times the mass of kaolin, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve.

[0056] The preparation method of modified rubber powder is as follows:

[0057] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0058] (2) The pretreated waste rubber powder, reinforcing agent and surfactant were mixed at 130°C for 45 minutes. After mixing evenly, the mixture was dried and ground through an 80-mesh sieve.

[0059] Comparative Example 2

[0060] This comparative example differs from Example 1 in that the auxiliary agents are different.

[0061] A modified rubber powder comprises the following raw materials, calculated by weight: 100 parts of waste rubber powder, 3 parts of additives, 15 parts of reinforcing agents and 7 parts of surfactants.

[0062] The additives are calculated by mass percentage as follows: 16% sodium oleate, 2% oxalic acid, and the balance is water.

[0063] The surfactant is selected from sodium lauryl sulfate.

[0064] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin is as follows: dispersing kaolin in an ethanol aqueous solution with a volume concentration of 45%, adding a silane coupling agent (γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane with a mass ratio of 1:0.4) 0.05 times the mass of kaolin, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve.

[0065] The preparation method of modified rubber powder is as follows:

[0066] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0067] (2) The pretreated waste rubber powder, reinforcing agent and surfactant were mixed at 130°C for 45 minutes. After mixing evenly, the mixture was dried and ground through an 80-mesh sieve.

[0068] Comparative Example 3

[0069] The difference between this comparative example and Example 1 is that the reinforcing agent is different, which is commercially available white carbon black.

[0070] A modified rubber powder comprises the following raw materials, calculated by weight: 100 parts of waste rubber powder, 3 parts of additives, 15 parts of reinforcing agents and 7 parts of surfactants.

[0071] The additives are calculated by mass percentage as follows: 8% polyoxyethylene nonylphenol ether, 8% sodium oleate, 2% oxalic acid, and the balance is water.

[0072] The surfactant is selected from sodium lauryl sulfate.

[0073] The reinforcing agent is white carbon black.

[0074] The preparation method of modified rubber powder is as follows:

[0075] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0076] (2) The pretreated waste rubber powder, reinforcing agent and surfactant were mixed at 130°C for 45 minutes. After mixing evenly, the mixture was dried and ground through an 80-mesh sieve.

[0077] The preparation method of modified rubber powder comprises the following steps:

[0078] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0079] (2) The pretreated waste rubber powder, reinforcing agent and surfactant are mixed and kneaded evenly, dried and ground through an 80-mesh sieve to obtain the product.

[0080] Comparative Example 4

[0081] The difference between this comparative example and Example 1 is that the reinforcing agent is prepared in a different method.

[0082] A modified rubber powder comprises the following raw materials, calculated by weight: 100 parts of waste rubber powder, 3 parts of additives, 15 parts of reinforcing agents and 7 parts of surfactants.

[0083] The additives are calculated by mass percentage as follows: 8% polyoxyethylene nonylphenol ether, 8% sodium oleate, 2% oxalic acid, and the balance is water.

[0084] The surfactant is selected from sodium lauryl sulfate.

[0085] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin includes dispersing kaolin in 45% ethanol aqueous solution, adding 0.05 times of silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve.

[0086] The preparation method of modified rubber powder is as follows:

[0087] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0088] (2) The pretreated waste rubber powder, reinforcing agent and surfactant were mixed at 130°C for 45 minutes. After mixing evenly, the mixture was dried and ground through an 80-mesh sieve.

[0089] Comparative Example 5

[0090] The difference between this comparative example and Example 1 is that the reinforcing agent is prepared in a different method.

[0091] A modified rubber powder comprises the following raw materials, calculated by weight: 100 parts of waste rubber powder, 3 parts of additives, 15 parts of reinforcing agents and 7 parts of surfactants.

[0092] The additives are calculated by mass percentage as follows: 8% polyoxyethylene nonylphenol ether, 8% sodium oleate, 2% oxalic acid, and the balance is water.

[0093] The surfactant is selected from sodium lauryl sulfate.

[0094] The reinforcing agent is nano-modified kaolin. The preparation method of the modified kaolin includes dispersing kaolin in 45% ethanol aqueous solution, adding 0.05 times of silane coupling agent γ-mercaptopropyltrimethoxysilane) and mixing, stirring at 65°C for 35 minutes, filtering, drying, grinding, and passing through a 400-mesh sieve.

[0095] The preparation method of modified rubber powder is as follows:

[0096] (1) soaking the waste rubber powder with an additive for 5 minutes, ultrasonicating for 30 minutes, standing and stratifying, removing the supernatant, washing with water, and removing the water to obtain the pretreated waste rubber powder;

[0097] (2) The pretreated waste rubber powder, reinforcing agent and surfactant were mixed at 130°C for 45 minutes. After mixing evenly, the mixture was dried and ground through an 80-mesh sieve.

[0098] The modified rubber powder prepared in each embodiment and comparative example was rolled into sheets and pressed into films according to the test formula for tensile strength and elongation at break in GB / T19208-2020 "Vulcanized Rubber Powder". The tensile strength and elongation at break were tested in accordance with the national standard GB / T 528-2009, and the Akron abrasion performance of the pressed films was tested in accordance with GB / T 1689-2014. The results are shown in Table 1.

[0099] Table 1 Mechanical properties test results

[0100]

[0101] After the above-mentioned sheeting and film forming were carried out using the rubber powder of Example 1 of the present invention, the remaining test results of the product are as follows in Table 2:

[0102] Table 2

[0103] No. Inspection items Technical requirements / standard values Test results This conclusion 1 Heating loss, % ≤1.0 0.3 qualified 2 Ash content, % ≤1.0 8 qualified 3 Acetone extract, % ≤8 5 qualified 4 Rubber hydrocarbon content, % >45 65 qualified 5 Carbon black content, % >26 29 qualified 6 Iron content, % <0.05 0.008 qualified 7 <![CDATA[Volume density, (kg / m 3 )]]> 260-380 321 qualified 8 Residue on sieve, % ≤10 0.01 qualified

[0104] The above detailed description is a specific description of one feasible embodiment of the present invention. This embodiment is not intended to limit the patent scope of the present invention. Any equivalent implementation or modification that does not depart from the present invention should be included in the scope of the technical solution of the present invention.

Claims

1. A modified rubber powder, characterized in that: The raw materials of the rubber powder include the following components by weight: 90-110 parts of waste rubber powder, 1-5 parts of additives, 10-20 parts of reinforcing agents and 5-10 parts of surfactants; The auxiliary agent comprises, by mass percentage, 5%-10% polyoxyethylene nonylphenol ether, 5%-10% sodium oleate, 1-5% oxalic acid, and the balance is water; The reinforcing agent is nano-modified kaolin, and the preparation method of the nano-modified kaolin comprises dispersing kaolin in an ethanol aqueous solution with a volume concentration of 30-50%, adding a silane coupling agent, mixing, stirring at 50-70° C. for 30-50 minutes, filtering, drying, grinding, and sieving to obtain the reinforcing agent. The silane coupling agent is γ-(2,3-epoxypropoxy)propyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane in a mass ratio of 1:0.2-0.

5.

2. The modified rubber powder according to claim 1, characterized in that The mass ratio of the kaolin to the silane coupling agent is 1:0.05-0.

1.

3. A method for preparing the modified rubber powder according to any one of claims 1 to 2, characterized in that: The steps include: (1) Soaking the waste rubber powder with an additive, ultrasonicating, standing and stratifying, removing the supernatant, and then washing with water to remove the water to obtain the pretreated waste rubber powder; (2) Mix the pretreated waste rubber powder, reinforcing agent and surfactant, mix them evenly, dry them, and grind them through an 80-100 mesh sieve to obtain the product.

4. The preparation method according to claim 3, characterized in that The soaking time in step (1) is 5-10 minutes, and the ultrasonication time is 10-30 minutes.

5. The preparation method according to claim 3, characterized in that The mixing temperature in step (2) is 130-145° C., and the mixing time is 20-45 min.

6. Use of the modified rubber powder according to any one of claims 1 to 2 or the modified rubber powder obtained by the preparation method according to any one of claims 3 to 5 in the preparation of tires, concrete or cables.

Images